United States
Environmental Protection
Agency
Water Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-87/103 Jan. 1988
&ERA Project Summary
Reclamation of Aluminum
Finishing Sludges
F. Michael Saunders
The reclamation of aluminum-
anodizing sludges produced as a result
of finishing extruded architectural
aluminum using etching and anodizing
processes was studied by Georgia Tech
Research Corporation. Two sequential
phases focused on (1) enhanced dewa-
tering of aluminum-anodizing sludges
with recessed-chamber filter presses
and (2) acidic extraction of dewatered
aluminum-anodizing sludges to pro-
duce commercial-strength solutions of
aluminum sulfate, i.e., liquid alum.
A high-pressure (14 to 15 bar) and
a diaphragm filter press were effective
in dewatering aluminum anodizing
sludges to cake solids contents of 27%
to 29% and 25% to 31%, respectively.
These values were well above the 21 %
value required to justify pursuit of
direct acidic extraction of aluminum.
Commercial-strength solutions of
aluminum sulfate with concentrations
of 8% as AI2Oa were produced using
conventional-neutralization, segre-
gated-neutralization, etch-recovery
sludge cakes. The trace metal contents
of the alum products were, in general,
typical of commercial products.
This Project Summary was devel-
oped by EPA's Water Engineering
Research Laboratory, Cincinnati. OH.
to announce key findings of the
research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering
information at back).
Introduction
Aluminum anodizing plants may pro-
duce up to 500 metric tons/month of
finished architectural aluminum extru-
sions. In the finishing process, approx-
imately 3% to 5% of the mass of the
extrusions is discharged as soluble
aluminum metal to plant wastewaters.
These aluminum-bearing wastewaters
are typically neutralized, resulting in the
production of a highly gelatinous,
aluminum-hydroxide suspension. When
these suspensions are thickened and
dewatered, the remaining wet residue
can equal or exceed the mass of finished
aluminum extrusions produced at a
plant. This solid waste residue must then
be disposed of in a landfill or by other
acceptable methods. Solid waste reduc-
tion, therefore, has an extremely high
priority in this industry and can be
addressed through alterations in
aluminum-finishing and waste-
treatment procedures or by reclamation
of the aluminum value in the dewatered
solid waste residue.
A major deterrent to the reclamation
of the aluminum value in aluminum-
anodizing sludges is the high levels of
moisture associated with dewatered
sludge cakes. Moisture generally consti-
tutes more than 80% of the total mass
of dewatered sludges, thereby increasing
sludge hauling and ultimate disposal
costs and contributing to the dilution of
the aluminum value. The high moisture
content is attributable to the gelatinous,
hydrophilic nature of the aluminum
hydroxide precipitate formed during
conventional neutralization of alumi-
num-anodizing wastewaters. To investi-
gate the extent to which sludge moisture
content could be reduced, recessed-
chamber filter presses were selected for
mechanical dewatering studies because
of the high pressure differentials (e.g.,
6 to 15 bar) typically achieved with these
systems and their ability to produce
dewatered sludge cakes with the lowest
moisture content achievable by conven-
tional mechanical dewatering systems.
-------
The production of liquid alum from
aluminum-anodizing sludges can be
represented by the addition of sulfuric
acid (H2SO«) to an aluminum-anodizing
sludge containing dry fixed solids,
represented by AI(OH)3, and moisture. In
an equation format, the acidic extraction
of aluminum is represented by:
2AI(OH)3 + xH2O + 3H2S04 — -
(1)
To produce a commercial-strength solu-
tion of liquid alum containing 26.8%
AI2(S04)3 (i.e., 8% as AI203), the
aluminum-hydroxide content of a sludge
would have to be equal to 1 6% on a fixed
solids basis. This value is indicative of
a total dry {1Q3°Q solids content of
approximately 21% for a dewatered
sludge cake. This is an exceptionally high
value that, when compared to current
practice, is not routinely achieved.
Therefore, effective dewatering of sludge
solids was a critical step in establishing
the potential for reclamation of
aluminum-anodizing sludges. Without
the ability to produce a dewatered sludge
cake with a solids content of > 21%,
further consideration of direct reclama-
tion of the aluminum value of aluminum-
anodizing sludge was futile.
Previous studies have been conducted
in the laboratory to establish the feas-
ibility of producing liquid alum from
aluminum-anodizing sludges. The pur-
pose of this study was to conduct
extractions with three types of
aluminum-anodizing wastes, to establish
the kinetics of the acidic extraction, and
to evaluate the quality of the products
produced.
Procedures
Two recessed-chamber, fixed-volume
filter presses (i.e., 470 mm and 250 mm)
were employed in the study to establish
the extent to which aluminum-anodizing
sludges could be dewatered. Low- and
high-pressure filtration studies were
conducted with the presses, and the
larger press was operated with variable-
volume diaphragm plates. Constant
operational pressure ranges of 6 to 7 bar
(87 to 102 psi) and 14 to 15 bar (203
to 218 psi) were employed throughout
the studies and are typical, respectively,
of low- and high-pressure systems
marketed for waste treatment practice.
Pressure filtration studies were con-
ducted at the site of an aluminum-
anodizing facility producing architectural
aluminum extrusions. Aluminum finish-
ing processes included alkaline cleaning,
caustic etching, acidic desmut, conven-
tional and two-step sulfuric acid anod-
izing, and hot-water sealing. Wastewater
treatment included neutralization with
spent acid and virgin caustic; polymer
flocculation; gravity sedimentation;
rotary vacuum filtration of thickened
sludge; and recycle of clarified water into
finishing rinses. Samples of the under-
flow suspension from the clarifier were
collected from the influent line to the
rotary vacuum filter and were examined
intensively on the filter presses. These
sludge suspensions were identified as
conventional neutralization (CN) suspen-
sions. A CN suspension from a similar
aluminum-anodizing plant was also
examined.
One other type of suspension was
examined during the pressure filtration
studies. Suspensions formed by batch
neutralization of spent caustic etch from
the aluminum-finishing line with spent
anodizing acid were identified as segre-
gated neutralization (SN) suspensions.
These suspensions were not produced in
the plant treatment systems, but were
produced experimentally in0.2-m3(~50-
gal) volumes for use in the filtration and
acidic extraction portions of the study.
These suspensions were formed by
pumping anodizing acid into an inten-
sively mixed, lined reactor containing
spent caustic etch until a pH of 9 to 10
was achieved. These suspensions were
then blended with CN suspensions or
used directly in pressure filtration
studies.
Acidic extraction of aluminum-
anodizing sludges was conducted in a
laboratory-scale reactor equipped with a
mixer and temperature control system
used to maintain post-acid-addition
temperatures at 50°C to 90°C. Following
addition of acid, samples were collected
at 30- to 60-min intervals to monitor the
progress of the reaction. A detailed
material balance was conducted on total
reaction mass and on the mass of
aluminum in each reactor.
Three types of suspensions were
examined. The CN and SN suspensions
as included in filter-press dewatering
studies were examined. In addition, an
etch recovery (ER) sludge provided by an
aluminum-anodizing plant was exam-
ined. This residue was produced from a
patented system designed to remove
aluminum from caustic etching
suspensions allowing for the continuous
recovery and reuse of the caustic etch
suspension. The aluminum is crystallized
as an aluminum hydrate (e.g., AlzO3 -x
H2O) at temperatures of 55°C to 65°C,
removed from the caustic etch, and water
washed using, for example, a vacuum
filtration system. The dewatered residue
was provided as one sample in 0.2-m3
volume and had a solids content of 91.6%
and an aluminum content of 43.6 g/100
g fixed solids.
Filter Press Dewatering
Typical characteristics of the suspen-
sions obtained from or experimentally
produced at two aluminum-anodizing
plants and examined during the filter
press studies are included in Table 1. The
two clarifier underflow suspensions, the
primary focus of the dewatering studies,
were slightly alkaline and relatively
dilute. The specific resistance values for
all suspensions were similar, although
that for the SN suspension was the
lowest, indicating slightly improved
dewatering characteristics. Although not
directly indicative of final cake solids
content for a mechanical dewatering
system, the dewatered cake solids
concentration (Ck) determined as a part
of the specific resistance test is effective
in indicating the relative potential to
which a suspension can be dewatered.
The clarifier underflow from plant X had
the lowest Ck value and was approxi-
mately 50% to 60% of that for the
neutralization basin effluent and clarifier
underflow from plant A. Furthermore, the
solids content values for all CN suspen-
sions ranged from 7% to 13%, well below
the minimum desired value of 21%,
indicating indirectly the nature of the
problem with respect to aluminum
recovery as liquid alum. SN suspensions
produced experimentally had exception-
ally high suspended solids concentra-
tions and the lowest and highest values
for specific resistance and specific-
resistance cake solids (Ck), respectively.
This indicated the high potential for use
of SN suspensions in the production of
liquid alum.
High-pressure and low-pressure filtra-
tion studies were conducted at constant
feed pressures of 6 to 7 bar (87 to 102
psi) and 14 to 15 bar (203 to 218 psi)
using two pilot-scale filter presses.
Replicate runs were usually performed
for an individual suspension at each feed
pressure with each replicate run being
conducted for a variable time of filtration.
For example, a CN suspension from plant
A was examined in one series of runs
at two concentrations and three filtration
-------
time intervals for each operational
pressure, as indicated in Table 2. Filtrate
volume data were also collected as a
function of time, as presented in Figure
1 for runs 24 through 29. The runs were
highly reproducible with respect to
filtrate volume. This allowed for evalua-
tion of the effect of filtration time on
dewatered cake solids, evaluation of the
ultimate filtrate volume that could be
produced at infinite filtration time, and,
thereby, the ultimate dewatered-cake
solids concentration, (Ck)uLT. Using a
procedure developed in conjunction with
this study, the ultimate filtrate volume
was established using a procedure
illustrated in Figure 2. With the projected
ultimate filtrate volume (i.e., filtrate
volume at a projected filtration rate of
zero), both the ultimate cake solids
concentration, (CK)ULT, and the cake solids
concentration at the point of collection
of 90% of the ultimate filtrate volume,
(Ck)o.9, were calculated. This is illustrated
in Table 3 for all low-pressure and high-
pressure runs with CN suspensions from
plant A. The ultimate cake solids con-
centrations, (Ck)uLT, for both low- and
high-pressure filtration were at or above
the desired value of 21%, as were all
(Ck)og values, indicating that it was
feasible to explore the acidic extraction
of sludge aluminum. Data collected for
a similar CN sludge from plant X indi-
cated that high- and low-pressure filtra-
tion produced(Ck)uLT values of 24.5% and
17.6%, respectively, indicating that only
high-pressure filtration would be accep-
table. Therefore, in general, CN sludges
can be dewatered to solids concentra-
tions ranging from 18% to 29% using
filter-press systems. Furthermore, high-
pressure systems appear most suitable
for production of dewatered sludge cakes
that are suitable for direct production of
liquid alum.
SN suspensions, produced by direct
neutralization of spent caustic etch
suspensions (containing elevated con-
centrations of aluminum, e.g., 50 to 150
g/L) with spent desmut or anodizing
acids, have better dewatering properties
than CN suspensions, as shown in Table
1. Samples of these experimentally
Table 1.
Typical Characteristics of Aluminum-Anodizing Suspensions from Participating
Plants
Suspended
Solids
SS, g/L
Specific
Resistance
r. Tm/kg+
a
.
Capillary
Suction Time
Seconds
Plant A
Neutralization basin 8.2
effluent
Clarifier underflow 8.2
Segregated 9.6
neutralization*
Plant C
Clarifier underflow 7.6
2.4
41
143
21
4
1.4
12
13
47
60
150
530
66
*Suspension produced experimentally at plant A but not a typical part of plant waste flow.
+TM/kg = 1012 meters/kg
Table 2. Results for Filter Press Dewatering of CN Suspensions (Plant A, Runs 24-29)
Influent Suspension
Runs
24,25.26
27.28.29
Suspended
Solids
9/L
73
37
Specific
Resistance
r. Tm/kg* Ck. %
3.6 15.4
2.6 14.7
Filtration
Pressure
bar
14-15
14-15
Time of
Filtration
min
75,50,35
156.90.68
Cake
Solids
%
28.1,26.4.25.3
28.9.25.1.23.6
* Tm/kg =10 meters/kg
produced suspensions were blended
with CN suspensions, since both would
be produced at a plant employing SN, to
determine the impact on dewatering.
Data in Table 4 indicate a dramatic
impact of SN solids on ultimate solids
concentration, as well as the high level
of cake solids concentration, i.e., 51%,
that can be achieved with SN suspen-
sions alone.
The use of variable-volume, or dia-
phragm, plates was examined on the
470-mm press using a low-pressure (6
to 7 bar) addition of a suspension to the
press followed by a high-pressure (15.5
bar) squeeze cycle, in which the contents
of each chamber were compressed until
no filtrate was released. Examples of the
filtrate volume collected with time during
the fill (or filter) and squeeze portions of
several replicate runs are presented in
Figure 3. Following filtration with the
diaphragm plates, the CN suspensions
from plant A had final cake solids
concentrations that ranged from 25% to
31% and averaged 29%. These values
were equivalent to or slightly higher than
the analogous (Ck)ui_T values obtained for
high pressure filtration (see Table 3). The
limited increase in cake solids concen-
tration would not appear to warrant the
use of diaphragm plates, although a
comparison of capital and operating costs
may dictate otherwise.
Acidic Extraction of Sludges
Extractions were conducted on numer-
ous aluminum anodizing sludges, follow-
ing dewatering by pressure filtration, and
on blends of dewatered sludges. Each
extraction was initiated by addition of a
fixed mass of sulfuric acid to a known
mass of dewatered sludge. A tempera-
ture control system was used to maintain
a prescribed control temperature. The
temperature, however, was not con-
trolled during the initial acid addition
phase but was controlled at tempera-
tures of 50°C to 90°C following dissi-
pation of heat associated with the initial
exothermic reaction.
The characteristics of the sludges
extracted are summarized in Table 5. The
aluminum content of the sludges,
expressed on a mass basis in terms of
the fixed (550°C) solids, varied from 31 %
to 43.6%, comparing favorably with the
AI(OH)3 form, with a theoretical alumi-
num content of 34.6%, used in Equation
1 to describe the chemistry of the acidic
extraction. Sulfuric acid was added to
dewatered cakes, in accordance with
Equation 1, at the rate of 1.89 g H2S04/g
-------
fixed solids or 5.44 g H2SO.i/g Al. Acid
doses were also expressed as a percen-
tage of the stoichiometric acid dose
based on sludge aluminum content (e.g.,
the addition of 5.44 g H2S04/g Al to a
sludge cake would represent a stoichi-
ometric dose of 100%).
Filtrate aluminum data in Figure 4
indicate the results of a typical acidic
extraction. In general, with an initial 1-
hr period, the aluminum contained in the
sludge cakes was extracted to near
completion and approached the concen-
tration of commercial-strength liquid
40
80 120
Time, min.
160
200
240
Figure 1. Cumulative filtrate volume for high-pressure (14 to 15 bar} dewatenng of CN sludges.
1.00
I I I ' ' ' ' I ' ' ' '
Run Number
• 24
• 25
» 26
X 27
O 28
•* 29
000
0.000
-*. —"V*.
. . . . X. : I . I ._ f ,
0050
0.100
Volume, mm3
0.150
0.200
Figure 2. Filtration rate for high pressure dewatenng of CN sludges and projection of ultimate
filtrate volume produced.
alum (i.e., 8% as AI203). Because of the
robust exothermic nature of the reaction
during the initial period, the controlled
reaction temperature had only a minimal
effect on the rate of the reaction, as
measured after a 0.5-hr extraction
period.
Data in Table 6 indicate that 89% to
109% of the aluminum placed in the
reactors was accounted for in the studies
conducted. In addition, the data indicate
that, for all but the ER cakes, 93% to
100% of the aluminum was extracted and
appeared in the soluble form as alum-
inum sulfate. Those instances in which
the percentage extracted was low (i.e.,
93%) were attributable to extractions in
which acid addition was less than the
stoichiometric amount.
For ER cakes, the level of aluminum
extracted ranged from 69% to 85%. In
some extractions of these cakes, dilution
water (required because of the high
solids content of these sludges) was
withheld until later portions of the
extraction. This produced an elevated
acid strength in the initial extraction
phase, and a higher level of aluminum
extraction (i.e., 81% to 85%), as com-
pared to those in which the additional
water was added prior to acid addition
and lower portions were extracted (i.e.,
68% to 69%).
The trace metal content of liquid alum
produced with CN-2, SN-1, and ER-1,
sludge cakes compared favorably with
commercial products. Data in Table 7
indicated that concentrations of cad-
mium, chromium, iron, silver, and zinc
in alum produced from aluminum-
anodizing cakes compared favorably with
those contained in commercial alum
products obtained from, and used at, two
large municipal water treatment plants.
The concentrations of lead were moder-
ately higher than those in the commercial
products.
Concentrations of nickel and tin in
alum produced from a conventional
sludge (CN-2) were significantly higher
than those in the commercial products.
This was attributed to the nickel and tin
used in the two-step anodizing process
atthe plant. Nickel and tin concentrations
in the alum produced from SN and ER
cakes were well below the concentra-
tions contained in the commercial prod-
ucts. Therefore, with the exception of
nickel and tin originating from a two-step
anodizing system, the levels of trace
metals contained in the alum produced
from aluminum-anodizing sludges were
similar to those contained in commercial
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Table 3. Predicted Cake Solids Concentrations for Filter-Press Dewatering of CN
Suspensions from Plant A
Range of
Suspended Solids
9/L
Predicated Cake Solids
Concentration
(CJULT, %
9, %
High pressure (14 to 15 bar)
21-73*
Low pressure (6 to 7 bar)
17-61 +
27-29
22-25
25-26
21-23
"Results for a total of 15 runs.
^Results for a total of 13 runs.
Table 4. Predicted Cake Solids Concentration for High-Pressure Filter-Press Dewatering of
Blends of SN and CN Suspension
SN Suspension in Blend of
SN-1 and CN-2 Suspensions
% (by volume)
0
5
15
30
100
Suspended
Solids
9/L
38
47
60
78
180
Predicted Cake Solids
Concentration
CC^ULT, %
29
33
37
39
51
(C>Joa, %
27
31
34
37
49
I
80
60
40
20
• 172 Filter
O Squeeze
• 175 Filter
[D Squeeze
V 176 Filter
A Squeeze
X 179 Filter
f(. Squeeze
0 40 80 120
Time. min.
Figure 3. Cumulative filtrate volume for filter and squeeze portions of diaphragm filter press
dewatering of CN sludges.
alum, indicating the potential utility of
the alum for use in coagulation of
drinking waters. However, since less
than 10% of commercial alum is actually
used in the treatment of drinking water,
it is apparent that the alum products
produced from aluminum-anodizing
sludges can be marketed for non-
potable-water uses in industry.
Conclusions
Research was conducted on filter-
press dewatering followed by reclama-
tion of three types of aluminum-
anodizing sludges as commercial-
strength liquid alum. Numerous conclu-
sions were drawn from the study.
Pressure filtration studies were con-
ducted with two pilot-scale, fixed-
volume, recessed-chamber filter presses
at low (6 to 7 bar) and high (14 to 15
bar) pressures. The solids content of
dewatered sludge cakes at the ultimate
completion of a filter press run were
projected from filtration rate data. CN
suspensions had ultimate cake solids
contents of 22% to 25% and 27% to 29%,
respectively, at low (6 to 7 bar) and high
(14 to 15 bar) pressures for suspensions
with suspended solids concentrations of
17to73g/L
SN suspensions could be effectively
dewat;red separately and resulted in
major improvements in the dewatering
of CN suspensions when blended with
them. At low and high pressures, ulti-
mate cake solids contents of 49% and
51%, respectively, were achieved with
SN suspensions. Blends of SN suspen-
sions at 5% to 30% volumetric ratios with
CN suspensions resulted in ultimate
solids contents of 33% to 39% with high-
pressure filtration and 31% to 37% with
low-pressure filtration.
A diaphragm press was used effec-
tively to dewater aluminum anodizing
suspensions. CN suspensions had final
cake solids contents of 25% to 31 %, while
5% to 30% volumetric blends of SN
suspensions with CN suspensions had
solids contents of 31 % to 43%.
Commercial-strength solutions of
liquid alum can be effectively and rapidly
produced with the addition of sulfuric
acid. Addition of stoichiometric quanti-
ties of acid, based on sludge aluminum
content resulted in virtually complete
extraction within 30 to 60 min.
CN sludge cakes with solids contents
of 17% to 18% were extracted to produce
liquid alum with concentrations of 7.4%
to 8.8% as AI2O3. A total of 93% to 97%
of the aluminum was extracted.
-------
C/V Dewatered Sludge Cake
Stoichiometric
Run Temp Acid Dosage
2-1 90°C 100%
2-2 50° C 100%
0 2 4 6 8
Time, hr
Figure 4. Filtrate aluminum concentration for sulfuric acid extraction of sludge cake CN-
2.
Table 5. Characteristics of Aluminum-Anodizing Sludge Cakes Used in Acidic Extraction
Studies
Cake Solids
Sludge Cake
Total. %
Fixed. %
Aluminum
Content
g/IOOg fixed solids
Conventional Neutralization
C/V-7
CN-2
Segregated Neutralization
S/V-7
Etch Recovery
ER-1
18.1
17.4
368
91 6
133
13.9
29.9
66.4
35.6
39.2
31.0
43.6
SN sludge cakes with solids contents
of 36.8% were extracted to produce liquid
alum with concentrations of 8.1% to
9.0% as AI203. An ER sludge with a solids
content of 91.6% produced a liquid alum
with a concentration of 8.3% to 9.2%
AI2Oa. Acid addition resulted in extrac-
tion of 69% to 85% of the aluminum.
Addition of SN or ER solids to CN solids
increased the aluminum content of the
blended sludge and could be effectively
extracted to easily produce commercial-
strength liquid alum.
The cadmium, chromium, and iron
concentrations of liquid alum produced
from CN sludges were less than those
of commercial alum products, while lead,
silver, and zinc concentrations were
slightly above those for commercial alum
products. The concentrations of nickel
and tin were sixfold to seventeenfold
higher than those in commercial alum.
The high nickel and tin concentrations
were attributed to dragout from the two-
step anodizing process and to the use
of nickel in seal tanks. Segregation of
these wastes from plant wastewaters
may be needed to eliminate them from
the sludges produced for extraction and
reclamation.
The full report was submitted in
fulfillment of CR110290-01-0 by Georgia
Institute of Technology under the spon-
sorship of the U.S. Environmental Pro-
tection Agency.
Blended Cakes
CN-2 & S/V-/
CN-2 & ER-1
25.2
30.2
21.4
22.5
34.6
41.3
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Table 6. Material Balance on Aluminum and Alum Product Quality for Acidic Extraction of
Sludge Cakes
Alum Product
Reactor Material AI extracted into
Balance-Aluminum soluble form Concentration
Sludge Cake %AI recovered % of total Al %asAI203
Conventional Neutralization
CN-1 104 93-97 7.4-8.0
CN-2 99 97 8.1-8.8
Segregated Neutralization
SN-1 100-105 99-100 8.1-9.0
Etch Recovery
ER-1
Blends
CN-2 & SN-1
CN-2 & ER-1
89-109
99
102
69-85
99
82
8.3-9.2
8.2
8.8
Table 7. Metal Content of Liquid-Alum Samples. Produced from CN-2, SN-1. and ER-1
Sludge Cakes, and Two Commercial Alum Products
Concentration, mg/L
Sludge-Cake Alum Commercial Alum
Metal
Cadmium, Cd
Chromium, Cr
Iron. Fe
Lead, Pb
Nickel. Ni
Silver, Ag
Tin, Sn
Zinc, An
CN-2
0.4
30.0
60.0
20
752
0.7
914
12
SN-1
0.3
4.4
18.3
19
8
0.2
28
6
ER-1
0.3
3.7
21.0
26
7
0.08
17
7
Plant 1
0.03
78
1845
6.6
44
0.25
155
8.5
Plant 2
0.3
0.9
2080
4.1
44
0.2
—
8.5
F. MichaelSaunders is with Georgia Institute of Technology, Atlanta, GA 30332.
Thomas J. Powers is the EPA Project Officer (see below).
The complete report, entitled "Reclamation of Aluminum Finishing Sludges,"
(Order No. PB 88-133 566/AS; Cost: $19.95, 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:
Water Engineering Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
-------
V
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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*SIMCT
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