&EPA
United States
Environmental Protection
Agency
EPA/540/MR-94/501
January 1994
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
Demonstration Bulletin
Colloid Polishing Filter Method
Filter Flow Technology, Inc.
Technology Description: The Filter Flow Technology, Inc. (FFT)
Colloid Polishing Filter Method (CPFM) was tested as a trans-
portable, trailer mounted, system that uses sorption and chemical
complexing phenomena to remove heavy metals and nontritium
radionuclides from water. Contaminated waters can be processed
by the CPFM system either as batch (using several thousand
gallons/cycle) or continuous (5 to 100-gallon per minute (gpm))
modes.
Contaminated water to be treated by the system is either pre-
treated to adjust chemical oxidation state and acidity (pH) in
mixing tanks or processed directly. After chemical pretreatment,
total suspended solids (TSS) are removed in a small, parallel
plate separator or mini-clarifier, and bag filters to prolong colloid
filter pack life. Effluent from the bag filter is routed to the colloid
filter units. Sludge from the mini-clarifier is pumped through a
small filter press and the filtered water is returned to the mini-
clarifier.
The sorption unit consisted of four horizontal polypropylene filter
plates that house three colloid filter packs. Each filter pack
Mini Clarifier
Mixing
Section
Contaminated
Groundwater
IJ^Srcrfrp
—I—N / i ift T
-cn
contains a proprietary, inorganic, insoluble, oxide-based, filter
bed material in particle and bead form. Operationally, the filter
packs are pneumatically pressure sealed between each set of
plates. The influent contaminated water is evenly dispersed
throughout the filter packs where contaminants are removed by
sorption, chemical mechanisms, chemical complexing, adsorp-
tion, and physical filtration.
Water traversing through the filter packs is collected and directed
to a final pH adjustment tank. If necessary, effluent from the
colloid filter unit is treated with acid in this tank to reduce the
effluent pH to 8.0 to 8.3 before discharge. Once treatment is
complete, air blow-down is used to dewater the filter bed, then
the hydraulic pressure on the support plates is released, the
plates are separated, and the filter packs are removed. Alterna-
tively, the filter media can be regenerated and reused. Spent filter
media is then mixed with solids from the mini-clarifier and bag
filters and stabilized to meet EPA land disposal restrictions.
Waste Applicability: FFT reports that the CPFM system has
effectively removed trace concentrations of colloidal, complexed,
Bag
Filters
Colloid
Filter Units
Filter Press
Solids To Disposal
pH Adjustment or
' Chemical Pretreatment
Hydrochloric
Acid
Solids
To
Disposal
Effluent
pH Adjustment
Tank
To
Discharge
Legend
^ Pump
Mixer
Flow Direction
Sample
Port
Note: Colloid Filter Units can be Oper-
ated in Series or Parallel Modes.
(Only Series Shown Here)
Figure 1. CPFM Treatment System
Printed on Recycled Paper
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chelated, and ionic heavy metals and nontritium radionuclides
from water that has been pretreated to reduce TSS. The CPFM
system removes a broad spectrum of heavy metal and radionu-
clide pollutants (excluding tritium) in surface or groundwater, waste-
water, or in secondary wastewater generated from soil washing.
Demonstration Approach: The U.S. Department of Energy (DOE)
and the EPA formed a cooperative effort to test and demonstrate
the CPFM system at Rocky Flats Plant (RFP), Golden, Colorado.
The demonstration evaluated the effectiveness of the technology
to remove low levels of radionuclides from contaminated ground-
water at RFP.
The FFT CPFM technology demonstration at RFP, began on
September 13, 1993, and lasted for 3 wk. During the demonstra-
tion, approximately 10,000 gal of contaminated groundwater con-
taining about 100 picoCuries per liter (pCi/L) was processed. The
groundwater used for the tests had been held in a 500,000 gal
storage tank for at least 2 mon and contained heavy algae
growth.
Operationally, the demonstration consisted of three tests. The
first test consisted of three runs of 4 hr each, treating about 5
gpm. For the second test, also run for 4 hr at 5 gpm, the influent
water was treated with sodium sulfide in the pretreatment tanks to
change the oxidation state of the radioactive metals in the water.
The third test was a 15-hr run, treating water at 5 gpm. The third
test was designed to estimate the amount of contamination each
filter pack is capable of treating.
During the demonstration, samples of untreated influent, pre-
treated water after passing through the mini-clarifier and bag
filters, and treated water that had passed through the filter packs,
were collected, and analyzed for a variety of parameters to evalu-
ate the technology's effectiveness. Adjustment of the influent pH
was not required at RFP because the influent water was within
the optimum pH range (7.5 to 9) for the technology. Because the
pH of the water increased during treatment, the pH of the effluent
water was monitored in the final pH adjustment tank and was
treated to reduce the pH to influent levels, as required by RFP.
Preliminary Results: Analytical results are expected to demon-
strate a significant reduction in heavy metals and radionuclides in
the CPFM effluent water. Bench-scale studies using RFP feed
water spiked with uranium, radium, plutonium, and americium
showed the following results:
Radiochemistry
Total Uranium
Gross Alpha
Gross Beta
Radium-226
Uranium-234
Uranium-238
Plutonium-239
Americium-241
Influent
(pCi/L)
98+12
166+.15
124±8
13±7
56±10
35±6
7±1
22±4
Effluent
(pCi/L)
0.15+0.12
23±6
57±7
7.4±7
<0.03
<0.03
<0.02
<0.01
% Removal
>99
86
54
46
>99
>99
>99
>99
The SITE evaluation will focus on the ability of the CPFM system
to remove uranium and gross alpha contamination from ground-
water, due to the low activity of plutonium and americium in the
influent. Key findings from the demonstration, including com-
plete analytical results and economic analysis, will be published
in a Capsule Report and an Innovative Technology Evaluation
Report. These reports may be used to evaluate the CPFM
technology as an alternative for cleaning up similar groundwater
contamination across the country. Results will also be presented
in a videotape.
For Further Information:
EPA Project Manager:
Annette Gatchett
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
(513)569-7697 Fax (513) 569-7620
Technology Developer Contact:
Tod Johnson
Filter Flow Technology, Inc.
3027 Marina Bay Drive, Suite 110
League City, TX 77573
(713)334-6080 Fax (713) 334-5993
*U.S.Gk»«mm«m Printing OHk»: 1984- 5604)87/80198
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
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POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/540/MR-94/501
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