United States Office of Solid Waste and Office of Research
Environmental Protection Emergency Response and Development
Agency Washington, DC 20460 Cincinnati, OH 45268
Superfund
EPA 540 2-90 009
September 1990
&EPA Abstract Proceedings:
Second Forum on
Innovative Hazardous
Waste Treatment
Technologies: Domestic
and International
Philadelphia, Pennsylvania
May 15-17, 1990
-------
EPA/540/2-90/009
September 1990
ABSTRACT PROCEEDINGS
SECOND FORUM ON INNOVATIVE HAZARDOUS
WASTE TREATMENT TECHNOLOGIES:
DOMESTIC AND INTERNATIONAL
Philadelphia, PA
May 15-17, 1990
OFFICE OF SOLID WASTE AND EMERGENCY RESPONSE
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, DC 20460
AND
RISK REDUCTION ENGINEERING LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI. OH 45268
U c!. EnvironmeirEaT £*•'•"~
r ' 3:1 5, Library (L
• '- n) B. Dearborn Sti--,\ /
GMoago, IL 60604
-------
NOTICE
The abstracts contained in this Proceedings do not necessarily reflect the
views of the Agency, and no official endorsement should be inferred.
Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
-------
ACKNOWLEDGMENTS
The Second Forum on Innovative Hazardous Waste Treatment Technolo-
gies: Domestic and International was sponsored by the U.S. Environmental
Protection Agency's (EPA's) Technology Innovation Office - Walter
Kovalick, Director.
The Forum programs and activities were planned by a committee consist-
ing of the following members:
Clarence Clemons, U.S. EPA, Center for Environmental Research Informa-
tion (CERI), Cincinnati, OH
Scott Fredericks, U.S. EPA, Office of Emergency and Remedial Response
(OERR). Washington, DC
Deborah Griswold, U.S. EPA, Region VI, Dallas, TX
Ronald Hill, U.S. EPA, Risk Reduction Engineering Laboratory (RREL),
Cincinnati, OH
Stephen James, U.S. EPA. RREL. Cincinnati, OH
Margaret Kelly, U.S. EPA, Technology Innovation Office (TIO),
Washington, DC
Walter Kovalick, U.S. EPA, TIO, Washington. DC
Fran Kremer, U.S. EPA, CERI, Cincinnati, OH
Lisa Moore, JACA Corporation, Fort Washington, PA
Robert Olexsey. U.S. EPA, RREL, Cincinnati. OH
Richard Steimle, U.S. EPA. TIO, Washington. DC
Thomas Pheiffer, U.S. EPA, TIO. Washington. DC
Tom Voltaggio, U.S. EPA, Region III. Philadelphia, PA
The conference was coordinated by JACA Corporation, Fort Washington, PA
19034 under subcontract to Dynamac Corporation, Rockville, MD 20852.
-------
ABSTRACT
On May 15-17, 1990. the U.S. Environmental Protection Agency's Technol-
ogy Innovation Office hosted an international conference in Philadelphia, PA,
to exchange solutions to hazardous waste treatment problems. This confer-
ence, the Second Forum on Innovative Hazardous Waste Treatment Tech-
nologies: Domestic and International, was attended by approximately 680
representatives from the U.S. and several foreign countries. During the
conference, scientists and engineers representing government agencies,
industry, and academia attended 35 presentations describing successful
case studies of physical/chemical, biological, thermal, and stabilization
treatment methods. In addition, case studies of applied technologies were
presented by EPA's Superfund contractors. Domestic and international sci-
entists and vendors presented over 50 posters explaining their treatment
methods and results. This document contains abstracts of many of the
presentations and posters from the conference.
-------
Table of Contents
PHYSICAL CHEMICAL TREATMENT METHODS 1
REMEDIATION AND TREATMENT OF SUPERFUND AND RCRA
HAZARDOUS WASTES BY FREEZE CRYSTALLIZATION 2
ACR/EPRI PROCESS FOR CLEAN-UP OF CONTAMINATED SOIL 3
INSITU HOT AIR/STEAM EXTRACTION OF VOLATILE ORGANIC
COMPOUNDS 4
EXTRACTION OF PCB FROM SOIL WITH EXTRAKSOL® 5
TYVEK® MICROFILTRATION OF HAZARDOUS WASTEWATERS 6
CLEAN-UP OF CONTAMINATED SOIL BY OZONE TREATMENT 6
BIOTROL® SOIL WASHING SYSTEM 7
DEVELOPMENT AND DEMONSTRATION OF A PILOT-SCALE
DEBRIS WASHING SYSTEM 8
INTEGRATED SOIL-VAPOR/GROUNDWATER EXTRACTION
CLEANING PROCESS 9
A REVIEW OF ULTROX® UV/OXIDATION TECHNOLOGY AS APPLIED
TO INDUSTRIAL GROUNDWATER, WASTEWATER, AND
SUPERFUND SITES 10
THE LURGI-DECONTERRA PROCESS - WET MECHANICAL SITE
REMEDIATION 11
THERMAL TREATMENT 12
DEVELOPMENTS AND OPERATING EXPERIENCE IN THERMAL
SOIL CLEANING 13
REVOLVING FLUIDIZED BED TECHNOLOGY FOR THE
TREATMENT OF HAZARDOUS MATERIALS 14
THERMAL GAS-PHASE REDUCTION OF ORGANIC HAZARDOUS
WASTES IN AQUEOUS MATRICES 15
X'TRAX® - TRANSPORTABLE THERMAL SEPARATOR
FOR ORGANIC CONTAMINATED SOLIDS 16
ANAEROBIC PYROLYSIS FOR TREATMENT OF ORGANIC
CONTAMINANTS IN SOLID WASTES AND SLUDGES - THE AOSTRA
TACIUK PROCESS SYSTEM 16
-------
BIOLOGICAL TREATMENT 18
ALGASORB® : A NEW TECHNOLOGY FOR REMOVAL AND
RECOVERY OF METAL IONS FROM GROUNDWATERS 19
BIOSORPTION - A POTENTIAL MECHANISM FOR THE REMOVAL
OF RADIONUCLIDES FROM NUCLEAR EFFLUENT STREAMS 20
BIOLOGICAL TREATMENT OF WASTEWATERS 21
BIOTECHNICAL SOIL PURIFICATION OF SOIL POLLUTED BY
OIL/CHEMICALS 21
IN SITU PHYSICAL AND BIOLOGICAL TREATMENT OF
VOLATILE ORGANIC CONTAMINATION: A CASE STUDY
THROUGH CLOSURE 22
SOLIDIFICATION/STABILIZATION TREATMENT 24
THE GEODUR SOLIDIFICATION PROCESS 25
CHEMFIX - HEAVY METAL SOIL FIXATION 26
AN EVALUATION OF THREE LEADING INNOVATIVE TECHNOLOGIES
FOR POTENTIAL CLEAN-UP OF BASIN F MATERIALS AT ROCKY
MOUNTAIN ARSENAL 26
SOIL VAPOR EXTRACTION AND TREATMENT OF VOCS AT
A SUPERFUND SITE IN MICHIGAN 27
SLUDGE AND SOIL TREATABILITY STUDIES AT A LARGE
SUPERFUND SITE 28
CRITICAL FLUID SOLVENT EXTRACTION 29
SOLVENT EXTRACTION - A CASE STUDY - BENCH-SCALE
TREATABILITY TESTING OF SOLVENT EXTRACTION FOR TREATMENT
OF WASTES AT THE ARROWHEAD REFINERY SITE, MINNESOTA 30
CONCEPTUAL COST EVALUATION OF VOLATILE ORGANIC
COMPOUND TREATMENT BY ADVANCED OXIDATION 31
RECOVERY OF METALS FROM WATER USING ION EXCHANGE 32
EVALUATION OF STABILIZATION/SOLIDIFICATION FOR CHROMIUM
REDUCTION AND IMMOBILIZATION FOR THE MOUAT, MONTANA SITE . . 33
FIELD DEMONSTRATION OF A CIRCULATING BED COMBUSTOR
(CBC) OPERATED BY OGDEN ENVIRONMENTAL SERVICES OF
SAN DIEGO. CALIFORNIA 34
LOW TEMPERATURE THERMAL TREATMENT (LT3) OF SOILS
CONTAMINATED WITH AVIATION FUEL AND CHLORINATED SOLVENTS . 35
-------
POSTER PRESENTATIONS 37
TOXIC METAL REMOVAL FROM AQUEOUS WASTE STREAMS
USING COMBINED CHEMICAL TREATMENT AND ULTRAFILTRATION 38
LEEP TECHNOLOGY SOIL REMEDIATION BY SOLVENT EXTRACTION ... 38
IN SITU ELECTROACOUSTIC SOIL DECONTAMINATION (ESD) PROCESS 39
EXXFLOW AND EXXPRESS MICROFILTRATION TECHNOLOGY 40
DIKLOR-S (CHLORINE DIOXIDE) TECHNOLOGY FOR WASTEWATER
APPLICATIONS 41
BIOREMEDIATION OF HAZARDOUS WASTES IN A SLURRY PHASE
THE EIMCO BIOLIFT® REACTOR 42
ALTERNATING CURRENT ELECTROCOAGULATION 42
PHYSICAL/CHEMICAL TECHNOLOGIES FOR SOIL DECONTAMINATION . . 43
QUAD CHEMTACT® MIST SCRUBBING TECHNOLOGY 44
VAPOR EXTRACTION SYSTEM 45
B.E.S.T. SOLVENT EXTRACTION PROCESS - TREATMENT OF
TOXIC SLUDGE, SEDIMENT. AND SOIL 46
INSITU SOLIDIFICATION/STABILIZATION - S.M.W.® TECHNIQUE 47
CHEMICAL SOLIDIFICATION AND STABILIZATION 48
STEAM INJECTION AND VACUUM EXTRACTION 49
VACUUM EXTRACTION TECHNOLOGY - SITE PROGRAM
DEMONSTRATION AT GROVELAND WELLS SUPERFUND SITE,
MASSACHUSETTS 49
TECHNOLOGY SUPPORT CENTER 50
BIOLOGICAL SOIL REMEDIATION SYSTEMS FOR ORGANIC POLLUTANTS 51
APPLICATION OF WASTECH, INC.'S CHEMICAL FIXATION/
STABILIZATION TECHNOLOGY 51
IN SITU PHYSICAL AND BIOLOGICAL TREATMENT OF COAL TAR
CONTAMINATED SOIL 52
A PERVAPORATION SYSTEM FOR VOLATILE ORGANIC
COMPOUND REMOVAL 53
PACT® SYSTEM TREATMENT OF GROUNDWATER. LEACHATES,
AND PROCESS WASTEWATERS WET AIR OXIDATION SYSTEM
FOR SLUDGE DESTRUCTION/STABILIZATION 54
-------
PHYSICAL/CHEMICAL TREATMENT METHODS
i i
-------
REMEDIATION AND TREATMENT OF SUPERFUND AND RCRA HAZARDOUS
WASTES BY FREEZE CRYSTALLIZATION
James A. Heist, Ken M. Hunt, Patrick J. Wrobel, Robert W. Connelly, and
Morton R. Herald
Freeze Technologies Corporation
P.O. Box 40968
Raleigh. NC 27629
Freeze crystallization is a separation process used to remove pure compo-
nents from solutions by crystallizing the materials to be removed. The
technology has proven advantages that make it economically attractive as
well as uniquely able to decontaminate many types of aqueous hazardous
wastes. This presentation illustrates how the process can be used in site
remediation activities, by-product recovery activities, and in the handling of
mixed (radioactive and hazardous) wastes.
Freeze Technologies Corporation (FTC) has built a 10 gallon per minute
(GPM) DirConw plant to demonstrate the freeze crystallization technology.
The plant is contained in two modules that can be transported by truck and
require less than one week to set up. The company's current demonstra-
tion project is scheduled for the Stringfellow site in Riverside, CA. Stringfel-
low is ranked high on the U.S. EPA's National Priority List (NPL) of Super-
fund sites targeted for remediation. The application is for a leachate from
interception wells.
Applications for freeze crystallization processing of hazardous wastes are
not limited to contaminated waters and wastewaters. The process has his-
torically been developed and used for organic separations applications.
Combinations of freezing with solvent extraction and soil washing also show
great promise for minimizing the volume of contaminant removed from a
waste/contaminated media.
Freeze crystallization has several advantages over competing technologies
for remediation and waste recovery applications. First, it is an efficient vol-
ume reduction process, producing a concentrate that has no additional
chemicals added to it. Volume reduction translates into reduced costs for
wastes requiring destruction by incineration or disposal in a landfill. When a
large fraction of the solvent (usually water) is removed from a waste, the
remaining impurities often begin to crystallize as well. These components
are often sufficiently pure to have by-product recovery value. Freeze crys-
tallization has low processing costs generally ranging from $.03 to $.15 per
gallon for 40 and 5 GPM plants, respectively.
-------
ACR/EPRI PROCESS FOR CLEAN-UP OF CONTAMINATED SOIL
T. Ignasiak
Department of Chemistry
University of Alberta
Edmonton, Alberta. Canada
C. Kulik
Electric Power Research Institute
Palo Alto. CA
B. Ignasiak
Alberta Research Council
P.O. Bag 1310
Devon. Alberta. Canada TOC 1EO
The Alberta Research Council (Canada) in conjunction with the Electric
Power Research Institute (USA) has developed a process for clean-up of
soil contaminated with various oily and organic waste materials. The proc-
ess that is applied for this purpose uses coal fines as a cleaning agent, and
capitalizes on the drastic variations in the oleophilic properties between
coal and mineral matter.
In principle, the process is based on specific oil agglomeration technique
(Aglofloat) developed at the Council, with organic contaminants acting as
the bridging liquid between coal particles. In the process, the contaminated
soil is mixed with a coal-water slurry: the products, in form of contaminant
wetted coal and cleaned soil, are separated by flotation. Both attrition,
which takes place during mixing, and sorption capacity of the coal, have a
major effect on process performance.
Bench-scale experiments have been conducted with samples contaminated
with coal derived tar, heavy oil. and oil spills. The effectiveness of the
cleaning procedure appeared to be dependent on the composition of the
contaminated samples and also on the particle size distribution of solids.
Both products, namely the processed soil as well as the oil-enriched coal,
have been extensively tested in terms of their leachability and organic con-
tents (soil) and handleability. leachability, and combustion characteristics
(oil-enriched coal).
The process appears to be very well suited for treating oil waste materials
originating from variety of coal/petroleum industries and it is now being
tested in a 6 ton per day continuous facility in order to generate engineer-
ing data for further development. Conceptual engineering and economic
-------
analyses indicate that the commercialization of the process is feasible.
The cost of treating one ton of contaminated soil varies from US $25-35
depending on the composition of the contaminated sample and plant
capacity.
INSITU HOT AIR/STEAM EXTRACTION OF VOLATILE ORGANIC
COMPOUNDS
Phillip N. La Mori
Toxic Treatments (USA) Inc.
151 Union Street, Suite 150
San Francisco, CA 94111
This paper presents results of using a new technology for the insitu re-
moval of volatile organic compounds (VOCs) from soil. The technology in-
jects hot air/steam into soil through two 5-ft-diameter counter rotating
blades that are attached to drill stems. The soil is cleaned as the drill
stems are advanced into and retracted from the ground. The evolved
gases are trapped in a surface covering called a shroud, and contaminants
are captured above ground via condensation and carbon absorption. The
recovered contaminants can be reprocessed or destroyed.
The results of the initial use of the commercial prototype show 85 to 99
percent removals of chlorinated VOCs from clay soils. The technology was
able to achieve its goal of less than 100 ppm over 80 percent of the time
in three blind tests. The mass of material recovered in the condensate was
conservative - approximately equal to the mass determined removed from
the soil by chemical analysis and physical measurements (89 %). The
technology also removed significant quantities (50%) of semi-volatile hy-
drocarbons (as quantified by EPA 8270). This was unexpected. Subsequent
analysis has identified potential mechanisms for removal of semi-volatile
components. Further testing is planned to evaluate these mechanisms.
The process has not been found to cause undesirable environmental emis-
sions as a result of its operation. Noise and air emissions during operation
are below the limits set by regional environmental regulations in southern
California. Soil hydrocarbon emissions during treatment are not increased
from background before treatment. Soil adjacent to the treatment has not
been found to have increased VOCs after the process is operated. Environ-
mental emissions caused by operational problems can generally be cured
without shutdown.
-------
EXTRACTION OF PCB FROM SOIL WITH EXTRAKSOL^
Diana Mourato and Jean Paquin
Environcorp Inc.
7777 Boul Louis-H
Lafontaine, Anjou
Montreal, Canada H1K 4E4
Polychlorinated biphenyls have been successfully extracted from clay-
bearing soil, sand, and Fuller's earth, by the Extraksol^ process. The
Extraksol® process is a mobile decontamination technology which treats
soil and sludges by solvent extraction. Treatment with Extraksol® involves
material washing, drying, and solvent regeneration. Contaminant removal is
achieved through desorption/dissolution mechanisms. The treated material
is dried and acceptable to be reinstalled in its original location.
The process provides a fast, efficient, and versatile alternative for treat-
ment of PCB-contaminated soil and sludge. The contaminants extracted
from the soil matrix are transferred to the extraction fluids. These are
thereafter concentrated in the residues of distillation after solvent regenera-
tion. Removal and concentration of the contaminants ensures an important
waste volume reduction.
Extraksol® is a flexible process designed to extract a variety of organic
contaminants from unconsolidated solids. Polyaromatic hydrocarbons, oils,
and pentachlorophenols have also been extracted from sludges, activated
carbon, porous stones, and gravel, with high removal efficiencies.
I I
TYVEK® MICROFILTRATION OF HAZARDOUS WASTEWATERS
Ernest Mayer
E.I. du Pont de Nemours & Co.
Engineering Department
P.O. Box 6090
Newark, DE 19714-6090
H.S. Lim
E.I. du Pont de Nemours & Co.
Tyvek® Technical Industrial Product Division
Richmond, VA 23261
Du Pont has developed and recently commercialized a new filter media
based on Tyvek® flash spinning technology. This new media has an asym-
metric pore structure, a greater number of submicron pores, and a smaller
-------
average pore size (1-3). As a consequence, it has superior filtration prop-
erties, longer life, and in many instances can compete with microporous
membranes. PTFE laminates, and various melt-blown media. When coupled
with an automatic pressure filter (APF), it provides an automatic was-
tewater filtration process that is a dry-cake alternative to conventional
crossflow microfilters and ultrafilters. This Tyvek® /APF process has proved
extremely useful in filtering heavy metal and other hazardous wastewaters
to meet strict EPA NPDES discharge limits. Specific examples and actual
case histories were highlighted to illustrate its benefits. In addition, this
Tyvek® /APF technology has recently been selected for EPA's SITE-3
program: this was also discussed.
I I
CLEAN-UP OF CONTAMINATED SOIL BY OZONE TREATMENT
M. PreuBer, H. Ruholl, H. Schindler, Ch. Wortmann, E. WeBling
Chemisches Laboratorium Dr. E. WeBling
OststraBe 2
4417 Altenberge, Federal Republic of Germany
A new technique which may be used to decontaminate soil containing dif-
ferent kinds of organic pollutants has been developed by our laboratory.
The method is based on the treatment of the contaminated soil with ozone
in the gas phase.
Ozone, the most powerful technically applied oxidizing agent, reacts with a
lot of inorganic and organic compounds. We were able to show that it de-
stroys both highly volatile aliphatic and aromatic hydrocarbons as well as
polycylic aromatic hydrocarbons in soil derived from former industrial
plants, coking plants, or gasoline stations. In the cleaning-up process, a
gas stream enriched with ozone passes through the soil, thereby reducing
the pollution up to 98 percent of the original concentration. The efficiency
of the method depends on several parameters, e.g., nature of the con-
tamination, condition of the soil and its permeability to gas, as well as the
presence of accompanying substances.
This new clean-up procedure may be used insitu or on-site. Experiments
have been carried out so far in laboratory and pilot-plant-scale. The first
large scale insitu treatment will start soon.
In laboratory experiments the ratio of pollutant concentration and employed
ozone quantity varied between 1:4 and 1:8. Organic compounds are trans-
ferred into substances which are highly biodegradable. There is no indica-
tion for the formation of toxic oxidation products.
-------
Ozone treatment destroys soil microorganisms to a large extent, but we
were able to show that the restoration of the soil micro flora can easily be
achieved, for example, by addition of the effluent of a sewage plant.
BIOTROL® SOIL WASHING SYSTEM
Steven B. Valine, Thomas J. Chresand, and Dennis D. Chilcote
BioTrol. Inc.
11 Peavey Road
Chaska. MN 55318
Soil washing is a process for treating excavated soils which are predomi-
nantly sand and gravel. In the process, contaminated soil is mixed with
water and subjected to several stages of intensive scrubbing followed by
classification. Several mechanisms can play a role in the treatment proc-
ess, including separation of highly contaminated fine particles from the
coarser sand and gravel, removal of surficial contamination from the coarse
soil fraction through abrasive action, and dissolution of soluble contami-
nants in the aqueous phase. The washed, coarser soil components are
then separated from the contaminated fine particles and process water,
significantly reducing the volume of material requiring additional treatment.
A pilot-scale soil washing system with a treatment capacity of 500 to 1,000
pounds per hour was operated at a Superfund site in Minnesota contami-
nated with wood preserving wastes, including pentachlorophenol,
polyaromatic hydrocarbons, copper, chromium, and arsenic. In general,
contaminant levels in the washed soil were 90 to 95 percent lower than in
the feed soil. Process water from the system was treated in a fixed film
bioreactor and recycled. A three-stage slurry phase bioreactor was used
to treat the contaminated fine solids. The results of this on-site pilot work
were discussed, including preliminary results obtained during an EPA Super-
fund Innovative Technology Evaluation (SITE) demonstration. The results of
bench-scale studies covering a wide variety of contaminants were pre-
sented, as well as the economics of full-scale treatment.
r ~ i
-------
DEVELOPMENT AND DEMONSTRATION OF A PILOT-SCALE DEBRIS
WASHING SYSTEM
Michael L. Taylor, Majid A. Dosani. and John A. Wentz
PEI Associates, Inc.
Cincinnati, OH 45246
Naomi P. Barkley, Donald E. Sanning, and Stephen C. James
U.S. Environmental Protection Agency
Cincinnati, OH 45268
Charles Eger
U.S. Environmental Protection Agency
Atlanta, GA
A large number of hazardous waste sites in the United States are littered
with metallic, masonry, and other solid debris which may be contaminated
with hazardous chemicals [e.g., polychlorinated biphenyls (PCBs), pesti-
cides, lead, or other metals] and in some cases clean-up standards have
been established (10|o,g PCBs/100 cm2 for surfaces to which personnel may
be frequently exposed). Although the majority of debris at Superfund sites
does not possess the potential for reuse, the debris could, following de-
contamination, either be returned to the site as "clean fill" in lieu of trans-
porting the debris offsite to a hazardous waste landfill or, in the case of
metallic debris, be sold to a metal smelter.
During previous phases of this project we have developed a technology for
performing on-site decontamination of debris. Both bench-scale and
pilot-scale versions of a Debris Washing System (DWS) have been de-
signed and constructed. The DWS utilizes an aqueous solution which is ap-
plied to the debris during a high pressure spray cycle followed by a turbu-
lent wash cycle. The aqueous cleaning solution is recovered and recondi-
tioned for use concurrently with the actual debris cleaning process; there-
fore the quantity of process water utilized to clean the debris is minimized.
The results obtained during a field demonstration of the DWS were pre-
sented. Data were presented which are indicative of the effectiveness of
the system for removing PCBs from the surfaces of metallic debris, as well
as the efficiency of the closed-loop solution reconditioning system, which
is built into the DWS. The performance of the DWS under adverse
(sub-freezing) temperature at a hazardous waste site located in
Hopkinsville. Kentucky, was also discussed.
-------
INTEGRATED SOIL-VAPOR/GROUNDWATER EXTRACTION CLEANING
PROCESS
Karlheinz Bohm and Gerrit Rost
Environmental Eng. Dept.
Ed. Zublin AG
Stuttgart, Federal Republic of Germany
An extraction process to remove VOCs from both groundwater and the
vadose zone has been developed by Ed. Zublin. This process involves on-
site regeneration of the carbon filter, eliminating periodic handling and re-
plenishment. The system is designed to recover most solvents which can
then be recycled or disposed. This feature is due to stringent air emission
controls in West Germany.
Case studies continually show similar operating characteristics under differ-
ent situations and varying contaminant concentrations. They demonstrate
that this technology has developed into a proven and reliable remedial
process.
The extraction process starts with a blower/vaccum pump creating a nega-
tive pressure causing the contaminated soil-vapor to flow toward the ex-
traction well. Contaminated groundwater is pumped and stripped of its con-
taminants. Both air streams are treated by passing over an activated car-
bon filter to remove the contaminants.
All VES treatment processes involve three phases: a high concentration
removal; a transitory phase; and an asymptotic phase. These phases can
last up to several months or years. The performance of extraction systems
is affected by several parameters.
Many Zublin installations combine the treatment of groundwater along with
soil-vapor. The dual phase system maximizes removal of contaminants and
minimizes the treatment period and pollution emissions. Cost efficiencies
are enhanced by on-site regeneration of the carbon and recovery of the
solvent.
-------
A REVIEW OF ULTROX® UV/OXIDATION TECHNOLOGY AS APPLIED TO
INDUSTRIAL GROUNDWATER, WASTEWATER, AND SUPERFUND SITES
David B. Fletcher
Ultrox International
2435 South Anne Street
Santa Ana, CA 92704
Ultrox Internationa! has demonstrated the efficacy of ultraviolet light-
enhanced oxidation at industrial, Department of Defense, and Superfund
sites. Waters containing halogenated solvents such as trichloroethylene,
perchloroethylene, and other halogenated compounds have been success-
fully treated with ULTROX® 's patented UV/ozone/hydrogen peroxide proc-
ess. Other contaminants such as aromatic solvents, hydrazines, phenols,
chlorophenols, dioxanes, PCBs, and pesticides in wastewaters and
groundwaters have also been treated to acceptable discharge standards.
BOD and COD levels have also been reduced to meet the requirements of
tougher effluent regulations. Summations of the above projects were pre-
sented, along with some of the technological basis of this process.
Commercial application of the technology is now growing rapidly. Design
and cost data from operations at full-scale commercial installations were
presented. The applications cover ultraviolet/oxidation systems treating
wastewater in the wood treating industry and chemical industry;
groundwater containing chlorinated solvents at automotive, aerospace, and
electronics manufacturers; and municipal drinking water treatment.
A summary of test results from a demonstration of the ULTROX® process
in the U.S. EPA Superfund Innovative Technology Evaluation (SITE) Program
was also presented. Constraints and limitations of the technology in light of
the above experience were discussed, as well as a comparison with other
technologies.
10
-------
THE LURGI-DECONTERRA PROCESS - WET MECHANICAL SITE
REMEDIATION
Eckart F. Hilmer
Lurgi GmbH, Dept. NAS
Lurgi-Allee 5
D-6000 Frankfurt
Federal Republic of Germany
For wet mechanical remediation, Lurgi has developed the Deconterra proc-
ess. This process is based on knowledge derived from processing of ores
and salts as well as silt from flowing and standing water, and on the engi-
neering experience Lurgi has accumulated in constructing many such
plants. The special feature of the Lurgi-Deconterra Process is the wet me-
chanical attrition. The energy required can be matched to the type of soil
and contamination. Energy of up to 16 kWhr/t can be transferred to the
material.
Only water without any addition of detergents or solvents is used as scrub-
bing liquid. The contaminated soil or debris after reclaiming is classified,
screened into different fractions, and crushed if necessary. Material dis-
charged from the attritioner drum undergoes further screening, gravimetric
sizing, sludge removal, froth flotation, and dewatering. The end products
are cleaned soil and debris and a contaminated concentrate which is com-
posed of the following materials separated in the process:
O light material from the gravimetric sizing (wood, tar, coal, coke)
O fine material from the hydrocyclone overflow
Q froth from the flotation
Furthermore, treatment of the contaminated concentrate may include incin-
eration in thermal treatment plants, solidification, pressure oxidation, or
biological treatment.
Lurgi-Deconterra plants are designed as semi-mobile systems, enabling a
quick move from one contaminated site to another. Material from all kinds
of contaminated sites such as coking plants, old ammunition plants, various
chemical industries, and railway repair shops have been treated in
Lurgi-Deconterra plants with very good results. Following the Dutch refer-
ence all cleaning results are either reference category A or between A and
B. Based on a Lurgi-Deconterra plant with a capacity of 25 t/hr throughput,
the treatment fee per ton is in the range of US$ 80-90. Excluded from this
amount are the costs for treatment of the highly contaminated residue.
11
-------
THERMAL TREATMENT
12
-------
DEVELOPMENTS AND OPERATING EXPERIENCE IN THERMAL SOIL
CLEANING
H.J. van Hasselt and A. Costerus
NBM Bodemsanering B.V.
P.O. Box 16032
2500 BA the Hague
Netherlands
NBM developed an indirect heated thermal system using a dryer and a ro-
tary tube-furnace. In indirect heating the soil does not come into direct
contact with the gases from the heating system. Within the closed tube,
the water vapor and the pollutants are released. Due to the small quantity
of these gases a small incinerator can be used and dust problems can be
handled easier. Finally, the flue gases from the burners remain clean and
the heat content can be recovered. After laboratory experiments and a
pilot plant phase, the first production plant was built in 1986. Up to Novem-
ber 1989, over 200,000 tons of soil, containing cyanides, aromatic hydro-
carbons, and oily type pollutants were cleaned. Typical cleaning results are
concentrations of less than 1 mg/kg total PAHs and less than 1 mg/kg total
cyanide.
At the Technical University of Delft, laboratory work was done to determine
the process conditions to bring the pollution levels below the accepted
("A" value, <0.1 mg organochlorine compound/kg) level and the process
conditions for incineration. Special attention was paid to the formation of
CDD and CDF. Based on the results of this laboratory work, NBM decided to
carry out practical experiments to prove that it is possible to clean soil
contaminated with halogenated hydrocarbons, and that safe incineration of
the offgases is possible.
The practical experiments were carried out in two phases. First, in 1989,
the incineration conditions were tested in the full-scale plant in Schiedam.
While running the plant with an input of sand contaminated with fuel oil a
known amount of a mixture of trichloroethene and tetrachloromethane was
injected into the incinerator, and stack emissions were measured. The de-
struction efficiency was higher than 99.999 percent.
Further experiments were carried out in April 1990. About 700 tons of soil
containing a.o. aldrin, dieldrin, and lindane were processed during a three-
day test run. In these tests, the rest of the concentrations of contaminants
were below the detection limit of 10 |o,g/kg dry solids.
13
-------
REVOLVING FLUIDIZED BED TECHNOLOGY FOR THE TREATMENT OF
HAZARDOUS MATERIALS
Geoff W. Boraston
Superburn Systems Ltd.
Suite 201-2034, West 12th Avenue
Vancouver. BC, Canada V6J 2G2
The Revolving Fluidized Bed is a patented fluidized bed design which has
very high combustion efficiency and can handle a wide range of materials
including soils, industrial sludge, municipal waste, sewage sludge, rubber
tires, and hazardous wastes. The material is burned very rapidly in a highly
turbulent bed of red hot sand which churns in an elliptical pattern. This "re-
volving" action enhances the mixing in the combustion area and also
moves large extraneous material to the edges of the furnace where it can
be easily withdrawn. This is a patented feature and has many benefits to
the combustion performance and the system's ability to handle a variety of
wastes.
There are over 50 installations world wide using the revolving fluidized bed
design. The systems range from small transportable units for soil cleaning
to larger 400 T/day municipal waste disposal plants.
Superburn is currently constructing a 360 T/day revolving fluidized bed in-
cineration plant in Sydney, Nova Scotia, Canada, for the Sydney Tar Pond
Clean-Up Project. Canada's largest hazardous waste site clean-up. The
total capital cost of the equipment is $16.5 million and will also produce up
to 10 MW of power which will be sold.
The tar pond sludge is a coke oven residue containing hazardous organics
which has accumulated to 700,000 tonnes in a small bay from the opera-
tion of a steel mill. The steel mill has now been converted to clean tech-
nology and the tarpond sludge will be disposed of in a Superburn plant.
Prior to contract award. Superburn conducted a series of trial burns on the
sludge in a 6 M Btu/hr demonstration plant in Vancouver, BC. The objective
of the trial burns was to confirm that stable operation could be achieved
and the Principal Organic Hazardous Components, mainly PAHs could be
destroyed with an efficiency of 99.99 percent. The revolving fluidized bed
operated stably without support fuel on the coke oven residue and
achieved DRE values on the POHCs of 99.99 percent to 99.9999 percent.
14
-------
THERMAL GAS-PHASE REDUCTION OF ORGANIC HAZARDOUS WASTES
IN AQUEOUS MATRICES
Douglas Hallett and Kelvin Campbell
Eco Logic
143 Dennis Street
Rockwood. Ontario, Canada NOB 2KO
Methods for the destruction of hazardous wastes containing chlorinated or-
ganic compounds such as PCBs have generally relied on some form of in-
cineration. Potential problems that are associated with incineration include
formation of small amounts of dioxins and furans, and the high cost of
burning wastes which are mainly water, such as harbour sediments and
landfill leachates.
Thermal gas-phase reduction of organic hazardous wastes in aqueous ma-
trices is an alternative to incineration that eliminates both of these prob-
lems. The reaction is conducted in a hydrogen-rich reducing atmosphere
with a complete absence of oxygen, resulting in virtually complete
dechlorination of organic molecules and production of lighter recoverable
hydrocarbons. After scrubbing the HCI from the gas stream, these hydro-
carbons may be used as fuel in the boiler that preheats the waste. No
chlorinated dioxins or furans are formed since the chlorine has been re-
moved.
ELI Eco Technologies is currently building a mobile system based on its
patented thermo-chemical process as a demonstration project for the Ca-
nadian Department of National Defense. The 2m diameter, 3m high reactor
is designed to process 4 kg/min of aqueous waste contaminated with 10
percent PCBs. The demonstration project will take place during the summer
of 1990.
15
-------
X*TRAX® - TRANSPORTABLE THERMAL SEPARATOR FOR ORGANIC
CONTAMINATED SOLIDS
Carl Swanstrom and Carl Palmer
Chemical Waste Management
Geneva Research Center
1950 South Batavia Avenue
Geneva, IL 60134
Chemical Waste Management (CWM) has developed a patented system,
X*TRAX® , that thermally separates organics from solids, such as soils,
pond sludges, and filter cakes, in an indirectly heated rotary dryer. Vapor-
ized organics and water are transported with a nitrogen carrier gas to a gas
treatment system where they are condensed and collected as a liquid. The
gas is then reheated and recycled to the dryer. To control oxygen, a small
portion of the carrier gas is vented to atmosphere through carbon adsor-
bers.
CWM has constructed a full-scale transportable X'TRAX® system that has
been contracted for a PCB soils clean-up at a mid-size Superfund site in
the Eastern U.S. The system is expected to mobilize in mid to late 1990 on
that site. In an innovative combination, the condensed organic liquid will be
chemically dechlorinated on site prior to off site disposal. A SITE demon-
stration test will be conducted at this site during the performance of the
clean-up. Since early 1988, CWM has operated both a 5 ton/day pilot
demonstration system, and a 2-4 Ib/hr laboratory system for treatability
studies. The pilot system has recently completed 10 tests using TSCA
regulated PCB soils and is currently in preparation for an extensive testing
program using RCRA regulated materials. In addition to a number of surro-
gate wastes, the laboratory system has processed over 19 RCRA and TSCA
regulated waste materials.
ANAEROBIC PYROLYSIS FOR TREATMENT OF ORGANIC
CONTAMINANTS IN SOLID WASTES AND SLUDGES - THE AOSTRA
TACIUK PROCESS SYSTEM
Robert Ritcey
Umatac Industrial Processes
210-2880 Glenmore Trail, S.E.
Calgary. Alberta, Canada T2C2E7
The AOSTRA Taciuk Process (ATP) is a thermal treatment technology which
has been developed and proven effective for separating organic contami-
nants such as oils and petrochemicals from solid wastes, soils, and
sludges. The process was developed jointly by the Alberta Oil Sands Tech-
16
-------
nology and Research Authority and UMATAC Industrial Processes for pro-
ducing bitumen from Alberta's oil sand deposits as distillate oil product, and
for producing oil from oil shales. The extensive test work in these fields,
and recent work directly with waste materials, are the background to the
recent commercial application of the ATP System in waste treatment.
The ATP technology is a continuous flow pyrolysis system which achieves
the separation of organic contaminants from host solids in the wastes, and
offers the advantages of minimum air emissions, ability to recycle the or-
ganics, rapid treatment of waste volumes, and low cost. The ATP System
has been extensively tested and its capability demonstrated for separating
water and organic contaminants from soils and sludges.
The plant is a recycling facility for those constituents in the waste which
are re-usable. It renders the solids free of the organic contaminant (s): the
liquid products (water and oil) for reuse, secondary treatment, or disposal;
and the air emissions meet regulatory criteria applicable to thermal
remediation treatment of wastes.
The first commercial ATP treatment plant has a design capacity of 10 tph
and was ready for service in September 1989. It will be employed in waste
treatment, initially on a PCB separation soil treatment Superfund project in
the U.S.A. The plant is portable and will be used on numerous job sites in
North America. Other remediation projects and applications for the ATP
technology and portable treatment plants of various sizes are being
developed.
17
-------
BIOLOGICAL TREATMENT
18
-------
ALGASORB® : A NEW TECHNOLOGY FOR REMOVAL AND RECOVERY OF
METAL IONS FROM GROUNDWATERS
Dennis W. Darnall, Sandy Svec. and Maria Alvarez
Bio-Recovery Systems. Inc.
P.O. Box 3982, UPB
Las Cruces, NM 88003
Bio-Recovery Systems has developed a new sorption process for remov-
ing toxic metal ions from water. This process is based upon the natural.
very strong affinity of biological materials, such as the cell walls of plants
and microorganisms, for heavy metal ions. Biological materials, primarily
algae, have been immobilized in a polymer to produce a "biological" ion
exchange resin. AlgaSORB® . The material has a remarkable affinity for
heavy metal ions and is capable of concentrating these ions by a factor of
many thousand-fold. Additionally, the bound metals can be stripped and
recovered from the algal material in a manner similar to conventional
resins.
This new technology has been demonstrated to be an extremely effective
method for removing toxic metals from groundwaters. Metal concentrations
can be produced to very low parts per billion (ppb) levels. An important
characteristic of the binding material is that high concentrations of very
common ions such as calcium, magnesium, sodium, potassium, chloride,
and sulfate do not interfere with the binding of heavy metals. Waters con-
taining a total dissolved solids (TDS) content of several thousand and a
hardness of several hundred parts per million (ppm) can be successfully
treated to remove and recover heavy metals. The process has been dem-
onstrated under the Emerging Technology program of the SITE program for
the effective removal of mercury from a contaminated groundwater.
19
-------
BIOSORPTION - A POTENTIAL MECHANISM FOR THE REMOVAL OF
RADIONUCLIDES FROM NUCLEAR EFFLUENT STREAMS
Peter Barratt
Biotreatment Limited
5 Chiltern Close
Cardiff CF4 SDL
United Kingdom
Of the various stages involved in processing and reprocessing in the nu-
clear fuel industry, many produce aqueous effluent streams which contain
both radioactive and non-active contaminants that can be considered haz-
ardous to the environment. Currently, a variety of techniques are used to
reduce the radionuclide loading of such effluents. These include filtration,
ion exchange, and adsorption to mineral lattices. Many of the treatment
processes currently in use demonstrate high efficiencies where substantial
concentrations of radionuclides are present. However, where effluent metal
concentrations lie in the lower range of 1 to 100 ppm, some of the classi-
cal treatments become less effective.
Biotreatment Limited is currently undertaking a laboratory research program
to assess the potential of various forms of microbial biomass as matrices
for the accumulation of metal cations that are of significance in nuclear re-
processing effluents. This study focuses on the biosorption of three of the
cations most significant in nuclear effluent streams (strontium, ruthenium.
and cobalt).
A selection of microorganisms, isolated from both natural and contaminated
environments, were screened for their ability to tolerate various concentra-
tions of the stable isotopes Sr, Ru, and Co. On the basis of this screening,
organisms were selected for further testing in small-scale liquid culture me-
dia and model effluent streams constructed in the laboratory. Complete
removal of Co and Sr from solution was demonstrated during 48h incuba-
tion at metal concentrations below 10 mg/l, using living cultures of
Trichoderma vlride and Penicillium expansum. although the composition of
the liquid medium significantly affected biosorption. Biosorption was much
less effective at metal concentrations between 30 and 200 mg/l. Some
systems containing microbial necromass (dead cells) also showed cation
removal from solution. Microbial biomass incorporated into a filter bed for
the treatment of model effluent streams showed limited success in remov-
ing metal ions, although recirculation of the stream may offer a more effec-
tive system in the future.
20
-------
BIOLOGICAL TREATMENT OF WASTEWATERS
Thomas J. Chresand and Dennis D. Chilcote
Biotrol, Inc.
11 Peavey Road
Chaska, MN 55318
The Biological Aqueous Treatment System (BATS) was demonstrated for
treatment of groundwater contaminated with pentachlorophenol (PCP). The
system employs indigenous microorganisms; however, it is also amended
with a specific PCP-degrading bacterium. Three flow rates were tested,
corresponding to residence times of 9, 3, and 1.8 hours. PCP removal
ranged from 97.6 to 99.8 percent, with average effluent PCP concentra-
tions as low as 0.13 ppm. It was shown that biological degradation was the
predominant removal mechanism while air stripping and bioaccumulation
were negligible. Acute biomonitoring with minnows and water fleas showed
complete removal of toxicity by the treatment system.
The BATS has also been shown to be highly effective for treatment of a
variety of wastewaters, including process water and lagoon water, and for
a wide range of contaminants. Results were presented on treatment of
gasoline, phenolic, and solvent-contaminated wastewaters.
BIOTECHNICAL SOIL PURIFICATION OF SOIL POLLUTED BY
OIL/CHEMICALS
Susanne Hansen
A-S Bioteknisk Jordrens
Maglehojvej 10
DK-4400 Kalundborg
Denmark
A/S Bioteknisk Jordrens has, during the three years of its existence,
treated 110,000 tons of polluted soil, in 550 cases ranging from 600 kg to
11,000 tons. The pollutants have in most cases been light fuel oil, but soils
polluted with the following have also been purified: gasoline, diesel, heavy
fuel oil, acetone, MIBK. fish oil, turpentine, ethylene gtycol, toluene,
xylene, hydraulic oil, lubricating oil, ether, isopropanol, talates, and
chlorobenzene.
The pollutants are microbiologically decomposed. The method is used in
two different ways. In soil polluted with "non-volatile" pollutants such as
light fuel oil, diesel/gasoline (which usually accompany each other),
21
-------
hydraulic oil, etc., these soil pollutants often consist of great volumes of
relatively mildly polluted material. The soil is arranged in elongated stacks
to separate one case from the other and facilitate treatment. Nutrients and
bacteria are added and the soil is aerated. The microbiological decomposi-
tion of the pollutants is monitored by means of gas chromatography. The
final content of oil before release for reuse is normally at a level where the
content of oil cannot be detected, which means <10 ppm oil with the
method of analysis applied.
In soil polluted with volatile and/or poisonous substances such as toluene,
xylene, MIBK, acetone, chlorobenzene, etc., this soil may involve a risk as
regards working environment. Purification takes place in a closed system
where the pollutants are driven out of the soil by means of air via a bottom
made of a specially developed perforated concrete clinker. The polluted
soil is taken to a compost filter where bacteria decompose the pollutant.
The method is also used in situ.
The basic price of soil purification of light components such as light fuel oil
is DKK 160.00 per ton (USD 20). Heavy pollutants such as hydraulic oil re-
quire a relatively longer purification period and are therefore relatively more
expensive. Soil purification of light fuel oil usually takes six months
(= USD 20/t), and where heavy fuel oil is involved the period required for
purification is one year (= USD 40/t).
IN SITU PHYSICAL AND BIOLOGICAL TREATMENT OF VOLATILE ORGANIC
CONTAMINATION: A CASE STUDY THROUGH CLOSURE
Richard Brown
LaCompagnie, GT Canada
8435 rue Notre-Dame
Montreal, Quebec, Canada H1L 3L3
Organic contamination of soils and groundwater can present a long-term
health and safety problem due to contamination of water supplies, and the
migration and accumulation of vapors in structures. Treating organic con-
tamination is a complex problem due to its complex phase distribution -
free phase, adsorbed, dissolved, and vapor phase. No single remedial
process is equally effective in dealing with all phases of contamination.
Successful remediation requires the application of multiple techologies such
as immiscible phase recovery, vapor extraction, and bioremediation. The
case history presented in this paper demonstrates the successful applica-
tion of this approach to the remediation of a site impacted by volatile
22
-------
petroleum hydrocarbons. The site treated was a retail gasoline station in
suburban Montreal that had impacted an adjacent commercial establish-
ment. Over a two and one-half year period the site was brought from
severe contamination to closure. The technology utilized was a combined
soil vent product recovery and bioreclamation system.
23
-------
SOLIDIFICATION/STABILIZATION TREATMENT
24
-------
THE GEODUR SOLIDIFICATION PROCESS
Svend Mortensen
Geodur A/S
Rigbakken 14, Ganloese
DK-3660 Stenloese
Denmark
During the last two years the Geodur solidification process has been devel-
oped and adapted to solidify/stabilize different hazardous chemicals in or-
ganic/inorganic soils and other solid waste materials. A pending patent has
been taken on the Geodur concentrate/additive which is the main sub-
stance of the Geodur process. The additive is produced on a natural mo-
lecular basis and totally free of poisonous matter, harmless for workers and
the environment.
The process consists of a mixing of the Geodur solution (Geodur concen-
trate in a ratio with water of 1:100) with the actual soil/solid waste. Portland
cement, and water. As a result of this concrete is produced. The Geodur
process activates chemically the natural bonding capabilities of the con-
taminated soil/solid waste by changing the surface tensions. This process
of agglomeration produces an ultimate stabilizing effect on the solid waste
product with high density and strength. The pH-factor of the soil/solid
waste does not have any influence on the final strength of the concrete
because it is controlled chemically by the Geodur solution.
The following kinds of soils and solid wastes have been solidified: Garden
topsoil, clay and clayey humus, sand and sandy humus, silt, desert sand
(salty), coast sand (salty), laterite, volcanic lava, mud (sediments with
blue clay), municipal sludge (heavy metals), hazardous chemicals and oil
contaminated soils, fly ashes, and stabilized and raw sulphite powder.
Apart from the leachability tests of contaminants, the chemical and
ecotoxicological properties of the leachate are studied together with the
mechanical strength and durability of the solidified materials. Petrographic
analyses have also been carried out. It should be mentioned that a special
ecotoxicological fouling test is carried out on different solidified materials
exposed insitu in receiving waters. On the basis of the promising results
with the process, Geodur now has the possibility for a full-scale mobile
plant with a capacity up to approximately 120 tons per hour.
25
-------
CHEMFIX - HEAVY METAL SOIL FIXATION
Philip N. Baldwin, Jr.
Chemfix Technologies, Inc.
Suite 620, Metairie Center
2424 Edenborn
Metairie, LA 70001
In 1988, Chemfix Technologies, Inc. was chosen to participate in EPA's
SITE Program at the Portable Equipment Salvage Company Superfund Site
in Clakamas, Oregon. Among the goals of this demonstration were to show
the viability of the CHEMSET^/CHEMFIX® process on heavy metal con-
taminated soil.
The treatment chemistry designed for the Program was waste specific and
included the use of CHEMSET^ reagents. Specially designed high solids
CHEMFIX® processing equipment was also employed.
Four individual areas were treated at the site, some with as much as
140,000 ppm of lead and 74,000 ppm of copper. The raw TCLP numbers
were as high as 880 ppm for lead and 120 ppm for copper. A reduction of
as much as 99+ percent in the TCLP mobility of these metals was demon-
strated while producing a useable soil-like finished product (NATURFIL® ).
AN EVALUATION OF THREE LEADING INNOVATIVE TECHNOLOGIES FOR
POTENTIAL CLEAN-UP OF BASIN F MATERIALS AT ROCKY MOUNTAIN
ARSENAL
Armand A. Balasco
Arthur D. Little, Inc.
Acorn Park
Cambridge, MA 02140
Our evaluation of innovative treatment technologies for the clean-up of
Basin F at Rocky Mountain Arsenal (RMA) was conducted for the U.S. Army
Toxic and Hazardous Materials Agency (USATHAMA) from July 1986 to July
1988. The arsenal is located just northeast of Denver, and covers approxi-
mately 17,000 acres. On-site operations, which ran from 1942 to 1982.
included chemical/incendiary manufacture and chemical munitions demilitari-
zation (both military operations), as well as insecticide/pesticide manufac-
ture by Shell Oil, which leased the facility from the Army in the early 1970s.
Both military and industrial operations generated a variety of wastewaters
that were disposed of in on-site lagoons, the best technology available at
that time.
26
-------
Three technologies were selected for laboratory or bench-scale evaluation
testing; fluidized/circulating bed combustion, glassification, and soil wash-
ing. Fluidized/circulating bed combustion appeared promising and
cost-competitive, but a major obstacle could not be overcome. Neither of
the two existing vendor test facilities equipped with the appropriate FBC
test equipment had the proper permits for operating with Basin F material.
Soil Washing proved effective. After the soil from Basin F was washed
through this process, we did a TCLP (Toxic Characteristic Leaching Proce-
dure - an EPA-recommended test) to find out if the effluents should be
classified as hazardous or nonhazardous. We found that while some target
contaminants remained - that is, some pesticides and metals were de-
tected - the levels were not measurable. Glassification process worked
successfully on the Basin F material; organochlorine compounds were re-
duced by more than 99.9 percent, organophosphorus compounds were
reduced by more than 99.7 percent, and organosulfur compounds were
reduced by more than 99.6 percent. TCLP leachate from the glass product
could be classified as nonhazardous since no target contaminants were de-
tected.
As a result of this technology review and testing, we recommended that
glassification should be the process pilot-tested on site at RMA. The cost
for clean-up would be high - up to $200-300 million for treating Basin F
material alone - but future government liability should be low because of
the final vitrified, highly leach-resistant state of the residuals; in addition.
the two-and-a-half-year time frame specified by the U.S. Army for Basin F
Clean-up could be met.
I I
SOIL VAPOR EXTRACTION AND TREATMENT OF VOCS AT A SUPERFUND
SITE IN MICHIGAN
Joseph P. Danko, Michael J. McCann, and William D. Byers
CH2M Hill
P.O. Box 428
Corvallis, OR 97339
The Verona Well Field supplies potable water to the City of Battle Creek,
Michigan, three townships, and another small city. The combined service
area equates to approximately 50,000 people. In 1981. the well field and
surrounding area were found to be contaminated with chlorinated solvents
and other volatile organic compounds (VOCs). The contaminant plume ex-
tended throughout an area approximately one mile by one-half mile. Two
facilities operated by a local solvent wholesaler/distributor were identified
as the primary sources of the contamination. VOC concentrations as high
27
-------
as 1,000 parts per million (ppm) were found in the groundwater and soil at
the wholesaler's primary facility.
EPA selected enhanced volatilization of VOCs using soil vapor extraction
(SVE) to clean up the contaminated soils. A pilot SVE system was installed
in late 1987 and operated for about 69 hours. Approximately 3.000 pounds
of VOCs were removed from the vadose zone during the pilot study. Using
the results of the pilot phase, a full-scale SVE system was designed and
installed in early 1988. The full-scale SVE system began operation in
March 1988. It has since removed more than 40,000 pounds of VOCs.
From system startup until January 1990, extracted vapors containing VOCs
were passed through vapor-phase activated carbon for treatment prior to
discharge. In January 1990, the carbon system was replaced by a catalytic
oxidation system capable of providing onsite destruction of VOCs. The
catalytic oxidation system is expected to provide more continuous opera-
tion and a cost savings over the life of the project.
SLUDGE AND SOIL TREATABILITY STUDIES AT A LARGE SUPERFUND SITE
Susan Roberts Shultz, Wendy Oresik, Doug Graham, Larry Kiener,
Sarah Levin, John Trynowski, and David Shultz
Donohue & Associates, Inc.
4738 N. 40th Street
Sheboygan, Wl 53083
The Bofors-Nobel (Bofors) Superfund Site, in Muskegon. Michigan, is under
management by the Michigan Department of Natural Resources, Grand Rap-
ids District, in cooperation with the United States Environmental Protection
Agency, Region V. Ten sludge lagoons were used at the site for waste dis-
posal from a chemical manufacturing facility. The sludge volume is approxi-
mately 120,000 cubic yards (yd3). The volume of contaminated soils
around the lagoons is approximately 748,000 yd3.
Compounds of concern were selected during the baseline risk assessment:
® Aniline o Benzidine
O Azobenzene o 3.3' - Dichlorobenzidine (DCB)
© Benzene o Methylene Chloride
These compounds are known, suspected, or potential human carcinogens.
Clean-up standards for the sludges and soils were developed based on
10~4 and 10"e excess cancer risks according to EPA guidelines.
28
-------
Soil washing, low temperature thermal desorption (LTTD), and solidifica-
tion/stabilization were selected for bench-scale treatability testing. Samples
indicative of worst-case soil, worst-case sludge, average soil, average
sludge, and average sludge and soil mixture were evaluated in the studies.
Results of the treatability studies are summarized below:
O Soil Washing: This process was not effective in cleaning
worst-case or average soil, specifically for DCB and azobenzene.
i> LTTD: This process appears to be effective for cleaning worst-case
soil and average sludge. LTTD was not effective for worst-case
sludge and average sludge and soil.
0) Solidification/Stabilization: Compounds of concern present in the
prestabilized TCLP extract were generally still present in the
stabilized TCLP extract in significant concentrations. Therefore.
stabilization does not appear to be effective for this site.
CRITICAL FLUID SOLVENT EXTRACTION
Cynthia Kaleri
U.S. Environmental Protection Agency
Region VI
1445 Ross Avenue
Dallas, TX 75202
Louis Rogers
Texas Water Commission
Austin, TX
Calvin Spencer
Roy F. Weston
Houston. TX
Solutions to today's environmental problems require the use of new tech-
nology or the application of existing technology in an innovative way. How-
ever, innovative applications of technology cannot be utilized in full-scale
site remediations until they have been evaluated for environmental and
economic effectiveness. The Superfund Innovative Technology Evaluation
(SITE) program was established to evaluate innovative uses of technology
in environmental clean-up operations. This paper presents the results of a
pilot-scale testing for a critical fluid solvent extraction technology on creo-
sote-contaminated soil at the United Creosoting Superfund Site in Conroe,
Texas. This paper presents an independent pilot study to evaluate critical
fluid extraction as a technical alternative.
29
-------
The critical fluid extraction technology utilizes a solvent near its critical
point, or state, to remove contaminants from various media. Under such
conditions, the solvent's properties are enhanced to obtain high removal
efficiencies and minimal residue is left in the media undergoing treatment.
In the case of United Creosoting. contaminated soils consisted of com-
pounds used in the former wood treating operations at the site: polynuclear
aromatic hydrocarbons (PAHs). pentachlorophenol (PCP), and trace dioxins
and furans. Propane gas was liquified by compression and used as the sol-
vent in an onsite pilot-scale unit. The soil was mixed with water and fed
into the extraction unit where the liquified propane dissolved the hydrocar-
bons from the soil slurry. The cleaned solids and water in the soil were al-
lowed to settle, while the contaminant/propane solution was passed
through a pressure reducing stage. The propane was vaporized in this
stage, leaving concentrated hydrocarbons which can be incinerated.
Samples of untreated and treated soil were analyzed for priority pollutant
organic compounds and dioxins. However. PAHs. PCP, and the dioxins
were the contaminants of concern and are summarized in this paper. The
onsite pilot testing of two 55-gallon drums at the United Creosoting site
demonstrated removal efficiency for PCP was approximately 91 percent.
Dioxins and furan removal efficiencies ranged from 66-83 percent.
SOLVENT EXTRACTION - A CASE STUDY - BENCH-SCALE TREAT ABILITY
TESTING OF SOLVENT EXTRACTION FOR TREATMENT
OF WASTES AT THE ARROWHEAD REFINERY SITE, MINNESOTA
Joseph Sandrin and John Fleissner
CH2M Hill, Inc.
P.O. Box 2090
Milwaukee. Wl 53201
Solvent extraction is a separation technology that has demonstrated some
applicability as a hazardous waste treatment technology, The technology
has been applied to industrial wastewater, soil, and sludges contaminated
with hydrocarbons, petroleum products, or heavy organic compounds. Ba-
sically, solvent extraction is a process that separates the waste feed
stream into oil (organic), water, and solid phases. Rather than destroy the
contaminants, the process yields products that may be more amenable to
treatment, disposal, or in some cases, recycling.
The Arrowhead Refinery Superfund site in Hermantown, Minnesota, is a for-
mer waste oil recycling facility. Sludge bottoms and residual oils mixed with
a clay filter cake were disposed of in a two-acre lagoon. The lagoon con-
tains an acidic, metal laden, viscous oily sludge mixed with clay, fill mate-
rial and the underlying peat. Adjacent surface soils throughout the site have
30
-------
also been contaminated with oil. and various organic and inorganic con-
taminants. The primary contaminants throughout the site are lead and
polynuclear aromatic hydrocarbons.
A bench-scale solvent extraction treatability test was performed on wastes
from the site by Resources Conservation Company (RCC) using their Basic
Extractive Solvent Technology (B.E.S.T.0^). Samples of the oily sludge.
oily peat, and contaminated soil were tested individually. Samples of the
untreated and treated wastes were analyzed through the TCLP to evaluate
the performance of this solvent extraction process. The results of the
bench-scale testing and a discussion of the performance of solvent extrac-
tion as a treatment technology for these wastes was presented.
CONCEPTUAL COST EVALUATION OF VOLATILE ORGANIC COMPOUND
TREATMENT BY ADVANCED OXIDATION
Glenn J. Mayer
CH2M Hill
2510 Red Hill Ave., Ste. A
Santa Ana, CA 92705
William D. Bellamy
CH2M Hill
Denver, CO
Neil Ziemba
U.S. Environmental Protection Agency
Region IX
San Francisco, CA
When VOCs were detected in the groundwaters of the San Gabriel Valley.
the valley was listed as a Superfund site. In the course of the remedial in-
vestigation (Rl), potable water treatment technologies were evaluated to
determine effectiveness in reducing contamination levels below drinking
water standards. Advanced Oxidation Processes (AOPs) are increasingly
being considered as alternatives to more traditional air stripping and carbon
adsorption processes. The effectiveness of ozone/hydrogen peroxide treat-
ment (one of many variations on AOPs) of water is strongly dependent on
local water chemistry (pH, alkalinity, hardness, total dissolved solids). A
bench-scale treatability study was conducted to determine the effective-
ness in treating trichloroethylene (TCE). tetrachloroethylene (PCE), carbon
tetrachloride (CTC), and trans-1,2-dichloroethylene (t-1,2-DCE) in San
31
-------
Gabriel Valley contaminated groundwaters. Results of the treatability study
indicated the following:
O a hydrogen peroxide/ozone molar ratio of 0.5 yielded higher VOC
oxidation rates and the most efficient use of oxidants compared to
other ratios,
O higher ozone mass feed rate yielded higher oxidation rates.
O reaction rate constants were essentially independent of VOC
concentrations,
© reaction rate constants for TCE and PCE were consistent with other
studies,
O gas stripping was small or negligible for t-1,2-DCE, TCE, and PCE.
Using data obtained during the treatability study, a conceptual cost evalu-
ation was prepared comparing the costs of air stripping with offgas treat-
ment using vapor phase carbon adsorption, liquid phase carbon adsorption,
and ozone/peroxide. Results of the feasibility study evaluation indicated the
following relative costs for a facility capable of treating 15,000 gallons per
minute contaminated with 75 ppb PCE, 15 ppb TCE. 20 ppb 1-1,2-DCE,
and 1.1 ppb CTC:
Ozone/peroxide treatment $0.14/1,000 gallons
Air stripping with offgas
treatment $0.10/1,000 gallons
Carbon adsorption $0.22/1,000 gallons
Ozone/peroxide treatment provides an added benefit of being a destructive
technology which reduces the mobility and toxicity of contaminants in the
treated waste stream. While ozone/peroxide treatment appears economi-
cal, additional pilot testing is required prior to actual application of the
technology.
RECOVERY OF METALS FROM WATER USING ION EXCHANGE
Thomas A. Mickey
B&V Waste Science and Technology Corp.
P.O. Box 7960
Overland Park, KS 66207
Ion exchange technology is being used to treat ground and storm waters at
a wood treatment facility in California as part of a comprehensive site
remediation program. Wood treating chemicals (inorganic metals) recov-
ered from the site waters are reused in the wood treating operation. Offsite
waste disposal is minimized and resource recovery is maximized.
32
-------
Through past operation of the wood treatment facility, chromium has been
released to the groundwater beneath the facility. Chromium and copper
residues are present in storm water runoff which is captured on the site.
Site investigations have determined the extent of groundwater contamina-
tion, and groundwater extraction and treatment remedial actions have been
implemented.
In 1987, an ion exchange water treatment plant was put into operation at
the facility. The ion exchange process captures hexavalent chromium from
the groundwater which is being extracted from beneath the site. The proc-
ess also captures copper and chromium which is in the storm water runoff
on the site. The ion exchange resins are regenerated periodically to re-
cover the captured wood treating metals in a concentrated form. The re-
covered metals are reused in the acid copper chromate (ACC) wood treat-
ing solution. To provide a regenerant stream suitable for reuse in the wood
treating process, weak base and weak acid ion exchange resins were
selected.
The water treatment plant has processed over 50 million gallons of water in
over two years of operation and has consistently met the effluent quality
limits. Operating problems encountered and overcome during the operating
history were presented.
EVALUATION OF STABILIZATION/SOLIDIFICATION FOR CHROMIUM
REDUCTION AND IMMOBILIZATION FOR THE MOUAT, MONTANA SITE
John A. Wentz, Michael L. Taylor, and Steve Giti-Pour
PEI Associates, Inc.
Cincinnati. OH 45246
Edwin F. Barth
U.S. Environmental Protection Agency
Cincinnati. OH 45268
In the late 1950s and early 1960s. Mouat Industries in Columbia, Montana,
operated a processing plant that converted ore to high-grade sodium di-
chromate. During the process, a sodium sulfite waste containing substantial
levels of sodium chromate and sodium dichromate was produced at the
Mouat plant. The soil and groundwater at the site became contaminated
with hexavalent chromium in the leachate from the waste sodium sulfite
stockpiles. Analyses of soil and groundwater samples conducted by the
Environmental Protection Agency and others in the 1980s led EPA to con-
clude that concentrations of toxic metals at the site were comparable to
background levels of the area, with the exception of chromium. Chromium
concentrations in the soil ranged from below 5 ppm to 3,100 ppm.
33
-------
This report describes a treatability study in which the immobilization of
chromium in soils from the Mouat site was assessed using acid washing,
chemical reduction, and solidification. The relative effectiveness of an initial
acid wash, and each of three reducing agents (sodium metabisulfite, fer-
rous sulfate, and standard slag), which converted Cr(VI) to Cr(lll) in
soil-cement matrices, were evaluated. Acid washing of the soil removed
93 percent of the Cr(VI) and 63 percent of the total chromium in the raw
soil. The acid-washed soil and acid-washed soil-cement matrices yielded
leachates (modified TCLP) which contained significantly less chromium than
the raw soil-cement matrix. For soils that are not going to be solidified,
acid washing of the soil and Cr(VI) reduction with ferrous sulfate proved to
be the best treatment. The use of standard slag as a reducing agent was
shown to be the best treatment for solidified, acid-washed soils. One ad-
vantage of using the standard slag for soils requiring solidification is that the
slag exhibits cement-like properties, thus decreasing the total quantity of
cement needed to stabilize the soil.
FIELD DEMONSTRATION OF A CIRCULATING BED COMBUSTOR (CBC)
OPERATED BY OGDEN ENVIRONMENTAL SERVICES OF SAN DIEGO,
CALIFORNIA
Nicholas Pangaro, Charles W. Young, and Douglas R. Roeck
Alliance Technologies Corporation/TRC Companies, Inc.
213 Burlington Road
Bedford. MA 01730
This field program involved the remediation of polychlorinated biphenyl
(PCB) contamination of the Swanson River Field, located on the Kenai Pen-
insula in southern Alaska. The Swanson River Field is located approximately
50 miles southwest of Anchorage in the Kenai National Wildlife Refuge.
Sampling and analysis of waste feed and effluent streams of the CBC during
the Demonstration Test program was performed. Representative samples
of waste feed (PCB-contaminated soil and gravel), spent bed material and
fabric filter ash (combined sample), and stack gas effluent were collected.
All sampled streams were analyzed for PCB concentration. Stack gas sam-
ples were collected to determine emission rates of PCB, chlorinated diben-
zodioxins and dibenzofurans (PCDDs/PCDFs). particulate matter, volatile
organics. and gaseous hydrogen chloride (HCI).
34
-------
Continuous emission monitoring of stack gas to determine concentrations
of oxygen, carbon dioxide, carbon monoxide, and oxides of nitrogen was
performed. Grab sampling of soil feed and spent ash materials, and sam-
pling for gaseous HCI on a rapid turnaround basis for potential modification
of the sorbent (limestone) feed rate was conducted during the field test
program.
The unit features a 30-inch internal diameter combustion zone measuring
approximately 33.6 feet in height. Bed solids, consisting of sand, lime-
stone, and feed material are purposely entrained and carried out the top of
the combustor. Solids are then collected by a cyclone and continuously
returned to the bottom of the incinerator. Gases exiting the combustor
pass through a three-zone heat exchanger consisting of water cooling
(Zone 1), preheating of ambient air for feeding into the combustor (Zone
2), and an air blast section using ambient air and discharging to atmos-
phere (Zone 3). Flue gas then flows to a fabric filter for particulate removal
prior to exhaust to the atmosphere.
This program was closely monitored by OTS and by Alaskan agency per-
sonnel. In June of 1989, Ogden announced that they had been issued a
nationwide federal permit for use of the CBC system for remediation of
PCB-contaminated soils.
I ""1
LOW TEMPERATURE THERMAL TREATMENT (LT3) OF SOILS CONTAMI-
NATED WITH AVIATION FUEL AND CHLORINATED SOLVENTS
Roger K. Nielson
Weston Services. Inc.
Weston Way
West Chester, PA 19380
Craig A. Myler
U.S. Army Toxic and Hazardous Materials Agency
Aberdeen Proving Ground. MD 21010
Successful pilot study of low temperature thermal treatment (LT3) (Patent
No. 4,738,206) of soils contaminated with volatile organic compounds led
to a full-scale demonstration to evaluate the use of this technology at DOD
installations. The LT3 process developed by Weston Services, Inc. under
contract with the U.S. Army Toxic and Hazardous Materials Agency
(USATHAMA) was used in a test of remediating soils contaminated with
aviation fuel (JP4) and trichloroethylene (TCE). Tinker Air Force Base.
Oklahoma, was selected as the demonstration site. An abandoned landfill
area had high concentrations of contamination in a clay soil, which was de-
termined to be ideal for this test. The LT3 process performed better than
35
-------
expected and achieved clean-up levels at lower temperatures, higher
processing rates, and shorter residence times than previously thought pos-
sible. This directly translates into cost savings for future remediation sites.
Test results indicative of the performance and potential application of this
technology were presented.
36
-------
POSTER PRESENTATIONS
37
-------
TOXIC METAL REMOVAL FROM AQUEOUS WASTE STREAMS USING
COMBINED CHEMICAL TREATMENT AND ULTRAFILTRATION
L.P. Buckley and S. Vijayan
Atomic Energy of Canada Limited
Chalk River Nuclear Laboratories
Chalk River, Ontario, Canada KOJ 1JO
J.F. Martin
Risk Reduction Engineering Laboratory
United States Environmental Protection Agency
26 W. Martin Luther King Drive
Cincinnati, OH 45268
The removal of selected soluble toxic metals from aqeuous solutions has
been achieved using a combination of chemical treatment and ultrafiltration.
Chemical treatment involves adjusting the alkalinity of the solution and add-
ing polyelectrolyte at the parts-per-million level. Bench- and pilot-scale
ultrafiltration experiments undertaken have realized removal efficiencies in
excess of 34-55 percent for typically-found average concentrations of the
toxic metals in groundwaters at Superfund sites. The program directed at
the bench-scale investigated process limitations, while the tests conducted
with the pilot-scale process equipment have provided data on longer-term
process efficiencies, effective processing rates, and membrane fouling po-
tential. Optimization of process variables, viz.. solution pH, polyelectrolyte,
polyelectrolyte concentration, and membrane material, has indicated what
the operating range should be to remove soluble metal cations from water.
The proposed technology has the potential to be applied successfully to
the selected removal of toxic metals in groundwaters at Superfund sites.
The final phase of the program involving a field demonstration at a uranium
tailings site was outlined.
LEEP TECHNOLOGY SOIL REMEDIATION BY SOLVENT EXTRACTION
Werner Steiner and Zvi Blank
ART International Inc.
273 Franklin Road
Randolph, NJ 07869
LEEP (Low Energy Extraction Process) is a new solvent extraction process
for the decontamination of earth materials containing organic pollutants.
The contaminants are leached with a water miscible solvent and subse-
quently concentrated in a water immiscible solvent for ultimate off site dis-
posal. The leaching solvent is recycled internally. LEEP is applicable to
38
-------
various types of earth materials ranging from dry topsoil to very wet sedi-
ments, as well as to refinery sludges.
Among the compounds which LEEP can remove from earth materials, are
some of the most prevalent pollutants, such as polychlorinated biphenyls
(PCBs), dioxin, polyaromatic hydrocarbons, pesticides, wood preserving
compounds, and petroleum products (e.g.. heating oil and gasoline) to
mention just a few. Results from bench-scale treatability studies conducted
with different matrices show very high removal efficiencies. A number of
compounds such as PCBs, polyaromatic hydrocarbons, and oil and grease
in refinery sludges have been removed to levels below the detection limits.
The LEEP technology, which operates at ambient conditions, is built from
simple, rugged pieces of equipment. Key process parameters can be ad-
justed to meet site specific requirements, which guarantees a complete
and efficient clean-up of virtually every organic compound. The technology
offers a cost effective way for on-site remediation of contaminated sites.
The development of the process concept and the early bench scale ex-
periments were conducted at New York University under an EPA grant. ART
International Inc. is currently building a trailer-mounted pilot plant. The work
is supported by EPA under the SITE Emerging Technologies Program. ART
International offers bench-scale treatability studies for the evaluation of the
LEEP technology to remediate particular sites.
IN SITU ELECTROACOUSTIC SOIL DECONTAMINATION (ESD) PROCESS
Satya P. Chauhan, H.S. Muralidhara, Bassam F. Jirjis, Robert E. Hinchee,
Foster B. Stulen, and G.B. Wickramanayake
Battelle Memorial Institute
505 King Avenue
Columbus, OH 43201
The technical feasibility of the electroacoustic soil decontamination (ESD)
process through laboratory experiments clearly demonstrated the re-
moval/concentration of heavy metals such as cadmium and zinc. Results of
the decontaminated soils were, however, inconclusive.
The ESD process is based on the application of a d.c. electric field and
acoustic field in the presence of a conventional hydraulic gradient to con-
taminated soils to enhance the transport of liquid and metal ions through
the soils. Electrodes (one or more anodes and cathode) and an acoustic
source are placed in contaminated soils to apply electric and acoustic
fields to the soil. This process works especially well with clay-type soils
having small pores or capillaries, where hydraulic permeability is very
slight. The process is suitable for in situ soil washing.
39
-------
The Phase I development program included a literature review, soil charac-
terization, design and construction of the laboratory ESD unit, and lab-scale
experiments with soils contaminated with decane, zinc, and cadmium.
Evaluation of the experimental results showed that application of the field
forces reduced zinc or cadmium metal concentration by more than 90 per-
cent. A maximum of 97.4 percent concentration reduction in cadmium and
92.3 percent reduction in zinc were obtained. The results of the organic
contamination (e.g., decane) were inconclusive as a result of the large
discrepancy in the decane laboratory analysis.
EXXFLOW AND EXXPRESS MICROFILTRATION TECHNOLOGY
Gary H. Bartman, K. Scott Jackson, and G. Raymond Groves
EPOC Water, Inc.
3065 Sunnyside, #101
Fresno. CA 93727
EPOC manufactures microfiltration membrane separation systems using tu-
bular woven textile modules. The process separates particles down to 0.01
micron and is used in a wide range of applications including soil detoxifica-
tion, hazardous waste reduction, water purification, and materials recovery.
Both the EXXFLOW and EXXPRESS systems use a rugged flexible material
which can be used with strong acids, strong bases, and can withstand op-
erating temperatures to 180°F. Operational difficulties associated with other
membrane separation processes have been virtually eliminated.
The EXXFLOW process removes heavy metals, pesticides, hardness, bac-
teria, and other impurities from water. EXXPRESS uses the same tubular
membrane in the press mode which automatically dewaters soils, sludges,
and aqueous wastes from toxic sites, industrial plants, food processes, and
municipal water works.
EXXFLOW and EXXPRESS have been commercially applied to several indus-
trial wastes including the removal of zinc and pesticides from pesticide
wastes, and lead, zinc, and cadmium from ceramics industry waste.
For the EPA SITE program, EPOC will demonstrate the ability of the
EXXFLOW/EXXPRESS system to successfully remove iron, copper, and
zinc from acid mine drainage water at an iron mine in Northern California.
The EXXFLOW unit will concentrate the precipitated heavy metals to a level
where they will be dewatered by the EXXPRESS unit. The results are ex-
pected to be a semi-dry cake of 40-50 percent solids and a discharge
water which will meet EPA discharge standards.
40
-------
DIKLOR-S (CHLORINE DIOXIDE) TECHNOLOGY FOR WASTEWATER
APPLICATIONS
Dave Skodack
Exxon Chemical Company
4510 E. Pacific Coast Highway
Mailbox 18
Long Beach, CA 90805
The technology used is based on the oxidation characteristics of chlorine
dioxide and the unique way in which the EXXON CHEMICAL COMPANY - RIO
LINDA CHEMICAL COMPANY process manufactures the oxidant and applies it
to waste streams. Chlorine dioxide is manufactured in a patented generator
that combines three separate chemical precursors. These precursors are
12.5 percent sodium hypochlorite, 15 percent hydrochloric acid, and 25
percent sodium chlorite.
The sodium hypochlorite and hydrochloric acid are combined in
stoichiometric ratios to form chlorine gas. The resulting chlorine gas is as-
pirated into a chamber where it is combined with sodium chlorite. When
these reactants come together in a reaction ratio of 1:2, one chlorine
molecule oxidizes two chlorite anions, converting them to two molecules of
chlorine dioxide. This reaction is instantaneous and can go to completion in
a very small, compact reaction chamber. This reaction produces 95 to 98
percent pure chlorine dioxide. The critical aspect of the chemistry of this
reaction is that molecular chlorine reacts with sodium chlorite faster than
the hydrolyzation reaction of the chlorine with water.
Historically, chlorine dioxide treatment systems have been applied to drink-
ing water disinfection, food processing sanitation, and as a biocide in indus-
trial process waters. Since chlorine dioxide reacts via direct oxidation
rather than substitution (as does chlorine), the process does not form un-
desirable trihalomethanes, an important feature when the chemical is ap-
plied to waste streams. This technology is applicable to aqueous wastes,
soils, or any leachable solid media contaminated with organic compounds.
It can also be applied to groundwater contaminated with pesticides or cya-
nide; sludges containing cyanide, sulfides, or other organics; and industrial
wastewaters similar to refinery wastewater. It has been applied to remove
phenols, mercaptans, thiosulfides, hydrogen sulfide, iron sulfide, and cya-
nide in a variety of industrial applications. Field application expertise and
rugged, portable, compact equipment has been jointly developed by the
two companies.
41
-------
BIOREMEDIATION OF HAZARDOUS WASTES IN A SLURRY PHASE -
THE EIMCO BIOLIFT® REACTOR
Gunter H. Brox and Douglas E. Hanify
EIMCO Process Equipment Company
P.O. Box 300
Salt Lake City, UT 84110
Biorernediation in the slurry phase offers distinct advantages over insitu
treatment, land treatment, or composting: better control of environmental
conditions, i.e.. pH. temperature, aeration, nutrients, desorption of con-
taminants into aqueous phase, and thus, more rapid treatment of certain
wastes. A closed reactor allows volatile emission control and operation in
aerobic or anaerobic mode. Potentially, genetically engineered bacteria will
first be used in closed reactor systems.
The EIMCO Biolift^ Reactor is a modified slurry agitator that uses a central
airlift, bottom rakes, and an innovative diffuser design to achieve the basic
objectives of mixing and aerating a slurry to sustain aerobic biodegradation
processes. It can handle slurries of 25 - 50 wt% solids concentrations and
provide mixing and aeration at a much lower energy consumption than con-
ventional liquids/solids contact reactors. Bioliff™1 Reactors are supplied in
four standard sizes ranging from 18.000 gallon to 300.000 gallon. Pilot
equipment is available for treatability studies.
The Biolift5* Reactor is being used in several RCRA and Superfund applica-
tions. A wide mix of organic contaminants have been degraded in different
soil and sludge matrices.
ALTERNATING CURRENT ELECTROCOAGULATION
Clifton ^arrell
Electro-Pure Systems, Inc.
10 Hazelwood Drive, Suite 106
Amherst, NY 14150
Hazardous constituents in wastewater may be suspended, emulsified.
and/or completely or partially solubilized. In the traditional method of treat-
ing multi-phase wastes, chemicals are added to encourage flocculation and
precipitation, as well as to enhance mechanical dewatering. A new technol-
ogy using alternating current electrocoagulation (ACE) can effectively
achieve phase separation of aqueous mixtures containing emulsified oils.
suspended solids, and various dissolved pollutants. This unique approach is
being developed by Electro Pure Systems. Inc.. a joint venture of Recra
Environmental, Inc. and Co-Ag Technologies.
42
-------
An alternating current electrocoagulator imposes an electric field on stable
suspensions and emulsions and rearranges surface charges, which in turn
facilitates particle flocculation and separation. Liquid/liquid and solid/liquid
phase separations are achieved without the use of expensive poly-
electrolytes. The process is also free of the excess waste solids attributed
to chemical aids. This technology is used to break stable aqueous suspen-
sions containing submicron-sized particles up to 5 percent total solids. It
also breaks stable aqueous emulsions containing up to 5 percent oil.
The ACE technology can be applied to a variety of aqueous-based suspen-
sions and emulsions typically generated as contaminated groundwater. sur-
face run-off, landfill leachate, truck wash, incinerator scrubber solutions,
treated effluents, and extract solutions. The suspensions include solids
such as: inorganic and organic pigments, clays, metallic powders, metal
ores, and natural colloidal matter. The emulsions include an array of or-
ganic solid and liquid contaminants including petroleum base byproducts.
ACE has been used to remove fines from coal washwaters and colloidal
clays from mine ponds in capacities up to 750 gpm. It has also been used
to remove suspended solids and heavy metals from pond water and
creosote-based contaminants from groundwater.
PHYSICAL/CHEMICAL TECHNOLOGIES FOR SOIL DECONTAMINATION
Robert D. Fox, Edward S. Alperin, and Victor Kalcevic
IT Corporation, Technology Development Laboratory
304 Directors Drive
Knoxville, TN 37923
IT Corporation is participating in the SITE Emerging Technologies Program
(ETP) with two pilot demonstration projects featuring innovative technology
combinations for soil decontamination. The first project, scheduled to be
complete by the end of 1990, uses batch steam distillation followed by
acid extraction to remove two common superfund site contaminants -
volatile organic compounds (VOCs) and heavy metals. The separation of
these contaminants from the soil is done batchwise in conventional equip-
ment by slurrying the soil in water. Batch operation facilitates process ad-
justments to meet changing feed compositions. The treated soil can be
returned to the site.
The second project has a duration of two years and will test the use of ul-
traviolet (UV) radiation to decompose polychlorinated biphenyls (PCBs) and
polychlorinated dibenzo dioxins (PCDDs) on soil and make them less recal-
citrant to biodegradation. The PCB photolysis residues will be further
43
-------
treated by biodegradation. Both sunlight and artificial UV light will be tested
on test plots of contaminated soil. A photolysis-enhancing surfactant will be
used to accelerate decomposition. Biodegradation tests will utilize indige-
nous microorganisms that have been enriched and propagated on
PCB-type compounds. Results from this project will be available in 1992.
I I
QUAD CHEMTACT® MIST SCRUBBING TECHNOLOGY
Harold J. Rafson
Quad Environmental Technologies Corp.
3605 Woodland Dr., Ste.103
Northbrook, II 60062
The patented QUAD Chemtact® Mist Scrubbing Technology for removing
gaseous contaminants has been in use for 15 years, with over 150 QUAD
systems in a variety of industrial-sized applications. Major applications have
been in odor removal for wastewater, rendering, paint resin, automotive
plants, and landfill gases. Odor applications are extremely difficult because
of the need to remove contaminants to levels of parts per billion.
Recent tests applied the Chemtact® systems to treating VOC emissions. In
an independent laboratory test, CH2M Hill reported high efficiencies of re-
moval for a wide range of chemical compounds - usually in excess of 98
percent. Direct comparisons were made with packed column systems
which showed only about 50 percent mass removals, and health risk meas-
urements often showed increases in health risk.
The Chemtact® system operates on different design principles from con-
ventionally designed scrubbers (i.e.. packed columns). There are four es-
sential differences:
1. Scrubbing solution is atomized to extremely fine droplets (of
approximately 10 microns), thus creating a dense fog:
2. Greater contact time between gas and liquid droplets;
3. Reactant chemical solution is once through, not recirculated;
4. Control instrumentation is used for rapid determinations and control
of inlet reactant chemical feed concentrations.
All of these factors combine to make the QUAD mist scrubber function
more effectively than conventional scrubber designs. Its benefits include
higher efficiencies of removal, lower operating cost, lower maintenance,
and lower quantities of liquid effluent to be treated.
44
-------
VAPOR EXTRACTION SYSTEM
Daniel J. Sullivan
Recycling Sciences, Inc.
30 S. Wacker Drive
Suite 1420
Chicago, IL 60606
The Vapor Extraction System (VES) uses a low-temperature, fluidized bed
to remove organic and volatile inorganic compounds from soils, sediments.
and sludges. Contaminated materials are fed into a co-current, fluidized
bed, where they are well mixed with hot gas (about 320°F) from a
gas-fired heater. Direct contact between the waste material and the hot
gas forces water and contaminants from the waste into the gas stream,
which flows out of the dryer to a gas treatment system.
The gas treatment system removes dust and organic vapors from the gas
stream. A cyclone separator and baghouse remove most of the particu-
lates in the gas stream from the dryer. Vapors from the cyclone separator
are cooled in a venturi scrubber, counter-current washer, and chiller sec-
tion before they are treated in a vapor-phase carbon adsorption system.
The liquid residues from the system are clarified and passed through two
activated carbon beds arranged in series. Clarified sludge is centrifuged,
and the liquid residue is also passed through the carbon beds.
By-products from the VES treatment include: (1) 96 to 98 percent of solid
waste feed as clean, dry dust; (2) a small quantity of pasty sludge contain-
ing organics; (3) a small quantity of spent adsorbent carbon; (4) waste-
water that may need further treatment; and (5) small quantities of
baghouse and cyclone dust.
This technology can remove volatile and semivolatile organics, including
polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons
(PAHs), and pentachlorophenol (PCP), volatile organics, and some pesti-
cides from soil, sludge, and sediment. In general, the process treats waste
containing less than 5 percent total organic contaminants and 30 to 90 per-
cent solids. Nonvolatile inorganic contaminants (such as metals) in the
waste feed do not inhibit the process, but are not treated.
45
-------
B.E.S.T. SOLVENT EXTRACTION PROCESS - TREATMENT OF TOXIC
SLUDGE, SEDIMENT, AND SOIL
Lisa C. Bobbins
Resources Conservation Company
3006 Northup Way
Bellevue, WA 98004
B.E.S.T. treats toxic waste by extracting contaminants from soils, sedi-
ments, and sludges. Wastes containing PCBs. PNAs. pesticides, and petro-
leum hydrocarbons have been successfully treated with the B.E.S.T. sol-
vent extraction process.
The process solvent, triethylamine (TEA), is unique. B.E.S.T. utilizes TEA'S
unusual ability to solvate both water and hydrocarbons. This multiple-misci-
bility characteristic of TEA allows removal of a broad array of contaminants
in a variety of waste matrices. For high water content wastes, such as
sludges and sediment, separation of clean water is as simple as increasing
the temperature of the extract. At warmer temperatures TEA is insoluble in
water, prompting the water to quickly settle into a distinct, separable
phase.
B.E.S.T.'s solubilization of water and hydrocarbons removes contaminants
from complex sludge emulsions and interstitial occlusions in soils. In this
way, solids are cleaned and separated for disposal or backfilling. Water
which is present in the waste feed will be carried through the process and
then removed for discharge. The hydrocarbon contamination is extracted
and concentrated reducing the overall volume of waste requiring regulated
disposal and destruction.
Process steps include extraction of water and organic contaminants, solids
separation and drying, and solvent recycle. TEA is 99.99 percent recycled
within the process. Soils processing configurations perform the extraction
and solids conditioning steps in a single vessel minimizing overall materials
handling operations.
The B.E.S.T. process has been tested on bench-scale with over 50 differ-
ent samples including soils, sediments, and sludges containing a multitude
of analytes requiring removal. RCC has an analytical lab for testing and
analysis. A pilot unit is also available for site demonstrations. The pilot unit
is skid mounted for easy transport and set-up. Full-scale demonstration of
the B.E.S.T. process occurred in 1987 at a Superfund site in Savannah.
Georgia. RCC treated approximately 4.000 tons of oily sludge which was a
viscous, acidic waste oil sludge containing heavy metals and PCBs.
46
-------
INSITU SOLIDIFICATION/STABILIZATION - S.M.W.® TECHNIQUE
Osamu Taki
S.M.W. Seiko, Inc.
100 Marine Parkway, Suite 350
Redwood City, CA 94065
The S.M.W.® Technique SITE Demonstration will involve insitu solidifica-
tion/stabilization of contaminated soils at depth. Treatment will be accom-
plished using multi-axis overlapping hollow stem augers to inject and mix
reagents with the soil. Any effective reagents that can be mixed in slurry
form can be applied. The final product will be a monolith of treated soil.
A test section was installed in May 1989, in Hayward, California. The insitu
mixing was performed in soils consisting of desiccated San Francisco Bay
Mud underlain by silt, sandy silt, and silty sand. The results proved the ca-
pability and efficiency of a newly developed S.M.W. auger for mixing plas-
tic silty clay.
The S.M.W.® Technique has a long history of successful geotechnical ap-
plications totalling 5 million cubic yards of soil-mixing work and including
soil stabilization and construction of soil-cement mixed cutoff walls and dia-
phragm walls. The technique has only recently been considered for con-
taminated soil treatment. Compared to other insitu treatments, the
S.M.W.® Technique is conducted in a well controlled and observable man-
ner. Because it is an insitu technique, normal waste exhumation concerns
such as air quality, excavation bracing, dewatering. and worker exposure
are mitigated.
The mixing augers are mounted on a crawler base machine and fed by a
computer-controlled mixing plant and flow control unit. Contaminated soils
varying from clay to gravel and cobble may be successfully treated. Insitu
treatment may be performed in both vadose and saturated soils.
47
-------
CHEMICAL SOLIDIFICATION AND STABILIZATION
William J. Sheehan
Separation and Recovery Systems Inc.
16901 Armstrong Avenue
Irvine, CA 92714
The SRS Chemical Solidification and Stabilization (C.S.S.) process provides
lime-based chemical fixation of hazardous organic and inorganic sludges.
The SRS C.S.S. process has been used commercially for over 12 years at
major sites on three continents. Over 500,000 cubic yards of hydrocarbon
sludges and contaminated soils have been treated to environmental
standards.
The sludge to be treated is removed from the waste pit and placed in a
blending pit. Specially prepared lime reagents are added to the sludge in
the blending pit using an excavator. The lime reagent is then mixed with
the sludge and the first step of the neutralization process takes place. After
approximately 15 minutes, a second lime preparation different from the first
in both chemical form and types of chemicals is added and mixed over a
20-minute period. After this time, the reaction is about 80 percent com-
plete. The treated material is then removed from the blending pit and
placed on the product assembly line. The product is allowed to cure for
approximately two days. After the product has been sufficiently cured, it
is placed in a storage area prior to return to the original pit for final
compaction.
The treated product is a soil-like material with very good structural proper-
ties and very low permeability. The process can treat a variety of wastes
as well as contaminated debris. Volume increase is 10 to 25 percent in
most waste compositions. Production rates are 300 to 900 cubic yards per
production day. A QA/QC evaluation is performed on each day's production
to assure that the material has been properly treated. For wastes that may
pose air emission potential, an enclosed process system is available. Proc-
ess costs range from $80.00 per cubic yard for the open system to
$120.00 per cubic yard for the enclosed system.
48
-------
STEAM INJECTION AND VACUUM EXTRACTION
Douglas K. Dieter
Solvent Service, Inc.
1040 Commercial Street
Suite 101
San Jose, CA 95112
This is an insitu process for extracting volatile and semi-volatile contami-
nants from soil. Steam is injected down wells and into the soil, giving ther-
mal and liquid-displacement enhancement to the vacuum extraction proc-
ess. Contaminants in liquids and gases are pumped to the surface where
they are treated by other processes (e.g., activated carbon). Ground-
water may be pumped along with the other liquids to clean saturated soil
zones and aquifers as well.
The process can be effectively applied to soils with high or low contami-
nant concentrations, so long as the contaminants mobilize, and are recov-
ered, at a significantly higher rate under the steaming conditions than under
the conditions of vacuum extraction alone. These requirements are met for
most soils contaminated with industrial solvents, fuels, and other organic
compounds.
This technology is currently being implemented at a State Superfund site in
San Jose, CA, and has been accepted by the EPA SITE program.
VACUUM EXTRACTION TECHNOLOGY - SITE PROGRAM
DEMONSTRATION AT GROVELAND WELLS SUPERFUND SITE,
MASSACHUSETTS
James J. Malot
Terra Vac, Inc.
P.O. Box 2199
Princeton, NJ 08543
Vacuum extraction is an insitu or exsitu treatment process for cleanup of
soils and groundwater contaminated with volatile organic compounds
(VOCs), liquid-phase hydrocarbons, or semivolatile compounds. Demon-
stration of the vacuum extraction technology was conducted under the EPA
Superfund Innovative Technology Evaluation (SITE) Program at the
Groveland Wells Superfund Site in Groveland, Massachusetts.
The subsurface conditions included multilayered glacial deposits consisting
of sands, silty sands, and clays. Groundwater was 27 feet deep with a
perched water table at about 10 feet.
49
-------
Objectives of the pilot program included testing of soils before, during, and
after implementation of the vacuum extraction process. The effectiveness
of the process was monitored by measuring subsurface vacuum, rates of
flow, rates of VOC extraction, and adsorption on activated carbon.
Results demonstrated the effectiveness of the vacuum extraction process
to clean up contaminated soils. In the area of the fringe of the contaminant
plume, soil concentrations were reduced more than 95 percent to non-de-
tectable levels. Additional data from subsequent clean-up work at the site
is available in several EPA publications.
I I
TECHNOLOGY SUPPORT CENTER
The Robert S. Kerr Environmental Research Laboratory
U.S. Environmental Protection Agency
P.O. Box 1198
Ada, OK 74820
The Superfund Amendment and Reauthorization Act (SARA) directs the U.S.
Environmental Protection Agency (EPA) to conduct a program of research,
evaluation, and demonstration of alternative and innovative technologies for
remedial response actions that will achieve more permanent solutions. Indi-
viduals making decisions concerning remedial action options must select
and/or approve effective remediation activities and technologies for each
specific site that will be protective of human health and the environment.
The Robert S. Kerr Environmental Research Laboratory (RSKERL) is EPA's
center of expertise for groundwater research, focusing its efforts on trans-
port and fate of contaminants in the vadose and saturated zones of the
subsurface and on subsurface processes for the treatment of hazardous
waste. RSKERL has established a Technology Support Center (TSC) to sup-
port remedial action decisions of regional and state Superfund personnel by
providing up-to-date subsurface fate, transport, and treatability information
plus associated expert assistance required to effectively use this informa-
tion. The TSC provides an avenue for exchange of the highly specialized
subsurface remediation information between the research and user commu-
nities. Results from research and other investigative efforts plus the back-
ground and experience of RSKERL and other scientists and engineers are
the basis of the information that is exchanged.
50
-------
BIOLOGICAL SOIL REMEDIATION SYSTEMS FOR ORGANIC POLLUTANTS
Volker Schulz-Berendt
Umweltschutz Nord GMBH & Co.
Bergedorfer Strasse 49
Ganderkesee, D-2875
West Germany
The regeneration of contaminated soil by microbial degradation depends on
the ability of bacteria and fungi to utilize organic pollutants as sources of
energy and nutrients. The biological degradation process depends on suit-
able conditions for the soil-microflora.
After the preparation of the soil by special machines for homogenization
and mixing additives like organic material, mineral nutrients, and adapted
bacteria, different systems could be used to maintain optimum conditions
during the degradation process.
Depending on the kind of pollutants, time of degradation, and assigned
reuse of the decontaminated soil, different remediation systems are ap-
plied. These systems are open-air degradation beds with a water circula-
tion system and vegetation, heaps enclosed in tents or other mobile con-
structions, stationary plants with integrated soil-treatment machines, or to-
tally closed bioreactors with installations for heating, watering, and pressure
control of the atmosphere.
Results of each of the systems with different pollutants, especially hydro-
carbons, were presented. Clean-up times range from three months up to
two years depending on kind and concentration of the pollutant, degrada-
tion conditions, and pollutant-concentration of the cleaned soil.
APPLICATION OF WASTECH, INC.'S CHEMICAL FIXATION/STABILIZATION
TECHNOLOGY
E. Benjamin Peacock
Wastech, Inc.
P.O. Box 1213
Oak Ridge, TN 37830
For years we have used available technology to solidify different forms of
liquid waste. Organic waste has always created a problem for final disposal
of materials. The contribution of the vast volumes of organic waste come
from all forms of industry. While the nuclear industry generates a minimum
amount of organic waste in comparison with the non-nuclear industry, their
51
-------
waste characteristics have a two-fold problem. With the latest changes by
the regulating bodies, these waste streams cannot be disposed of at a nu-
clear waste landfill because of the chemical toxicity. However, these waste
streams cannot be disposed of at a hazardous waste landfill due to the ra-
dioactive materials content. The past practice of disposal of this waste in
the liquid state, has proven to be unsatisfactory. Not only has this waste
exhibited its ability to breach the integrity of the burial site, but it has
proven to be an effective transport mechanism for moving other radio-
isotopes from the confines of the disposal site.
The non-nuclear industry has an equally restrictive situation. The generation
of organic compounds grows into several millions of metric tons each year.
The available disposal sites, which presently receive these materials, has
decreased in numbers as well as received more restrictive governmental
disposal criteria. This coupled with the ever increasing processing/disposal
charges, has handicapped the small/medium-size business in competing
for available revenue. Additional technology has been developed, and can
be used by the industry to dispose of an array of organic materials effec-
tively. The final end product may qualify for a reclassification of the mate-
rial (s), due to the decrease in toxicity. The poster presented at this con-
ference illustrated the effectiveness of this process and provided suppor-
tive laboratory data of the actual decrease of the toxicity of the raw mate-
rial (s).
IN SITU PHYSICAL AND BIOLOGICAL TREATMENT OF COAL TAR
CONTAMINATED SOIL
Lyle A. Johnson, Jr.
Western Research Institute
P.O. Box 3395, University Station
Laramie, WY 82071
Alfred P. Leuschner
Remediation Technologies. Inc.
9 Pond Lane
Concord, MA 01742
Dense organic liquids such as coal tars, chlorinated hydrocarbons, and
heavy petroleum products have contaminated groundwater at numerous
domestic and international industrial sites. The Western Research Institute
has developed a new in situ process to contain and recover oily wastes.
The Contained Recovery of Oily Wastes (CROW©) process uses hot-water
displacement to reduce concentrations of oily wastes in subsurface soils
and underlying bedrock. In this process, the contaminated area is hydrauli-
cally isolated so that contamination is not spread into uncontaminated ar-
52
-------
eas. The downward penetration of dense organic liquids is reversed by
controlled heating of the subsurface to float oily wastes in water. The
buoyant wastes are displaced to production wells by sweeping the subsur-
face with hot water. Waste flotation and vapor emissions are controlled by
maintaining both temperature and concentration gradients near the ground
surface. Reducing waste concentrations to residual saturation immobilizes
the oily wastes. Following completion of the CROW© process, an in situ
biological treatment process can be initiated for further treatment of the
residual organic saturation.
Remediation Technologies Inc. is evaluating in situ bioremediation proc-
esses for remediating soils and groundwater contaminated with biodegrad-
able contaminants by enhancing the growth and activity of aerobic bacte-
ria. These microorganisms use the contaminants as a source of carbon and
energy while converting them to carbon dioxide and water. The process
involves installing a groundwater injection and extraction system that allows
for the controlled transport of an oxygen source (typically hydrogen perox-
ide) and water soluble nutrients (typically nitrogen and phosphorus) be-
tween injection and extraction points. Oxygen and nurtrients are required to
promote and sustain the microorganisms needed to effect the degradative
process. In addition, in vessel biological treatment of CROW© process
product water is also being evaluated.
A PERVAPORATION SYSTEM FOR VOLATILE ORGANIC
COMPOUND REMOVAL
Chris Lipski, Peter Connell, and Pierre Cote
Zenon Environmental Inc.
845 Harrington Court
Burlington, Ontario, Canada L7N 3P3
Abbas Zaidi
Wastewater Technology Centre
867 Lakeshore Rd.
Burlington, Ontario, Canada L7R A46
The removal of volatile organic compounds (VOCs) from water has be-
come an increasingly important environmental issue. About half of the 129
U.S. EPA priority pollutants are VOCs and are known to be toxic and/or
carcinogenic. Pervaporation uses organophilic membranes to selectively
remove VOCs from contaminated water, such as groundwater leachate.
The organic compounds pass through the membrane, are drawn off by
vacuum, and condensed. Unlike conventional treatment technologies (e.g.
air stripping and granular activated carbon), pervaporation can recover
53
-------
valuable organic compounds from water for reuse, and can be run continu-
ously without regeneration.
Preliminary tests indicated that the liquid film boundary layer, rather than
the membrane itself, becomes rate controlling for most conventional per-
vaporation modules. Arising from the need for a hydrodynamically efficient
pervaporation module, the Wastewater Technology Centre approached
Zenon Environmental Inc. to develop the required module. Operating costs
for the new module, at first projection, are competitive with air stripping
using off-gas treatment by activated carbon. The new pervaporation mod-
ule holds great potential for sufficiently dealing with VOC contaminated
water.
cm ~ _: zzzzi ~ i
PACT® SYSTEM TREATMENT OF GROUNDWATER, LEACHATES. AND
PROCESS WASTEWATERS WET AIR OXIDATION SYSTEM FOR SLUDGE
DESTRUCTION/STABILIZATION
J.K. Berrigan. Jr., W.M. Copa, and V.T. Buehler
Zimpro/Passavant Inc.
301 W. Military Road
Rothschild. Wl 54476
Two innovative treatment processes from Zimpro/Passavant. the PACT®
system and Wet Air Oxidation (WAO). were selected for the SITE program
in 1987 and tested at bench-scale in 1989 prior to full-scale demonstration
on-site. The PACT® system combines biodegradation and adsorption of
organic contaminants by adding powdered activated carbon to a biological
treatment process. Current installations successfully treat refinery, fuels.
chemical, dye production, and pharmaceutical wastewaters, leachates,
contaminated groundwater. and combined municipal-industrial wastewater
containing hazardous organic chemicals. PACT® , when coupled with WAO.
provides complete destruction of many toxic components and reduces re-
siduals to a stable, sterile, inert ash - the only solid residue for disposal.
As part of the SITE demonstration, contaminated groundwater from the
Syncon Resins Site in Kearny. New Jersey, was treated at the Zimpro/Pas-
savant Testing and Development facility (a permitted hazardous waste
treatment, storage, and disposal facility, No. WID044393114) in Rothschild.
Wisconsin. All 11 priority pollutants in the groundwater were reduced to be-
low detection limits. COD of the groundwater was reduced by 85 percent,
to less than 125 mg/l. BODs was reduced by more than 93 percent to less
than 10 mg/l. Unfortunately, the Syncon Resins Site was not available for
the full-scale demonstration. EPA is continuing to search for a suitable site.
54
-------
When EPA selects a site, the PACT® system and WAO will be demon-
strated together to treat contaminated waters with various levels of organic
chemicals. A skid-mounted PACT^> system will treat contaminated waters.
A skid-mounted WAO system will demonstrate destruction of adsorbed
pollutants and bio-solids, while regenerating the powdered activated
carbon for reuse. At higher operating temperatures, the WAO system will
demonstrate conversion of sludges to a stabilized ash.
*US GOVERNMENT PRINTING OFFICE 1 990-748-1 59'20438
55
------- |