9
       •&ERA
                                   United States
                                   EnvkwHTientel Protection
                             Office of Emenjency and
                            Office of
                            Research and Development
                            Cincinnati, OH 45268
Superfund
EPA/540/2-90/013
SeptembeM990
                                   Engineering Bulletin
        Purpose

            Section 121(b) of the Comprehensive Environmental
        Response, Compensation, and Liability Act (CERCLA) mandates
        the Environmental Protection Agency (EPA) to select remedies
        that "utilize permanent solutions and alternative treatment
        technologies or resource recovery technologies to the maximum
        extent practicable" and to prefer remedial actions in which
        treatment "permanently and significantly reduces the volume,
        toxicity, or mobility of hazardous substances, pollutants and
        contaminants as a principal element." The Engineering Bulletins
        are a series of documents that summarize the latest information
        available on  selected  treatment and  site  remediation
        technologies and related issues.  They provide summaries of
        and  references for the latest information to  help remedial
        project managers,  on-scene coordinators, contractors,  and
        other site cleanup managers understand the type of data and
        site characteristics needed to evaluate a technology for potential
        applicability to their Superfund or other hazardous waste site.
        Those documents that describe individual treatment
        technologies focus  on remedial investigation scoping needs.
        Addenda will be issued periodically to update the original
        bulletins.
        Abstract

            Solvent extraction does not destroy wastes, but is a means
        of separating hazardous contaminants from soils, sludges, and
        sediments, thereby reducing the volume of the hazardous
        waste that must be treated. Generally it is used as one in a series
        of unit operations, and can reduce the overall costfor managing
        a particular site.  It is applicable to  organic wastes and is
        generally  not used for treating inorganics and  metals [15,
        p.64].* The technology uses an organic chemical as a solvent
        [14, p. 30], and differs from soil washing, which generally uses
        water or water with wash improving additives. During 1989,
        the technology was one of the selected remedies at six Superfund
        sites. Commercial-scale units are in operation. There is no clear
        solvent extraction technology leader by virtue of the solvent
        employed, type of equipment used, or mode of operation. The
        final determination of the lowest cost alternative will be more
        site specific than process equipment dominated. Vendors should
        be contacted to determine the availability of a unit for a
        particular site.  This bulletin provides information  on the
        technology applicability,  the types of residuals produced, the

        * [reference number, page number]
                                latest performance data, site requirements, the status of the
                                technology, and sources for further information.
                                Technology Applicability

                                    Solvent extraction  has  been shown  to  be effective in
                                treating sediments, sludges, and soils containing primarily
                                organic contaminants such as polychlorinated biphenyls(PCB),
                                volatile organic compounds (VOC), halogenated solvents, and
                                petroleum wastes. The technology is generally not used for
                                extracting inorganics (i.e., acids, bases, salts, heavy metals).
                                Inorganics usually do not have a detrimental effect  on the
                                extraction of the organic components, and sometimes metals
                                that pass through the process experience a beneficial effect by
                                changing the chemical compound to a less toxic or leachable
                                form. The process has been shown to be applicable  for the
                                separation of the organic contaminants in paint wastes, synthetic
                                rubber process wastes, coal  tar wastes, drilling muds, wood
                                treating wastes, separation sludges, pesticide/insecticide wastes,
                                and petroleum refinery oily wastes [3].

                                    Table 1 lists the codes for the specific Resource Conservation
                                and Recovery Act (RCRA) wastes that have been treated by this
                                technology [3][1, p.11 ].  The effectiveness of solvent extraction
                                on general contaminant groups for various matrices is shown
                                in Table 2 [13, p.1 ] [ 15, p.10]. Examples of constituents within
                                contaminant groups are provided in Reference 15, "Technology
                                Screening Guide for Treatment of CERCLA  Soils and Sludges."
                                This table is based on the current available  information or
                                professional judgment where no information was available.
                                The proven effectiveness of the technology for a particular site
                                or waste does not ensure that it will be effective at all sites or that
                                the treatment efficiencies achieved will be acceptable at other
                                sites.   For the  ratings  used for this table,  demonstrated
                                effectiveness means that, at some scale treatability was tested
                                to show the technology was  effective for  that  particular
                                contaminant and matrix. The ratings of potential effectiveness,
                                or no expected effectiveness are both based upon  expert
                                judgment.  Where potential effectiveness is  indicated, the
                                technology is believed  capable of successfully treating the
                                contaminant group in a particular matrix. When the technology
                                is not applicable or will probably not work for a particular
                                combination of contaminant group and matrix, a no-expected-
                                effectiveness rating is given.
                                                                                                  Printed on Recycled Paper

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Limitations
    Organically bound metals can co-extract with the target
organic pollutants and become a constituent of the concentrated
organic  waste stream.  This  is an unfavorable  occurrence
because the presence of metals can restrict both disposal and
recycle options.
                        Table 1
            RCRA Codes for Wastes Treated
                 by Solvent Extraction
     Wood Treating Wastes                     K001
     Water Treatment Sludges                   K044
     Dissolved Air Flotation (DAF) Float            K048
     Slop Oil Emulsion Solids                    K049
     Heat Exchanger Bundles Cleaning Sludge      K050
     American Petroleum Institute (API)
        Separator Sludge                       K051
     Tank Bottoms (leaded)                     K052
     Ammonia Still Sludge                      K060
     Pharmaceutical Sludge                     K084
     Decanter Tar Sludge                       K089
     Distillation Residues                       K101
                        Table 2
         Effectiveness of Solvent Extraction on
           General Contaminant Groups for
              Soil, Sludge, and Sediments

Treatability Croups



•§
?
0




^
|
p


j
Halogenated volatiles
Halogenated semivolatiles
Nonhalogenated volatiles
Nonhalogenated semivolatiles
PCBs
Pesticides
Dioxins/Furans
Organic cyanides
Organic corrosives
Volatile metals
Nonvolatile metals
Asbestos
Radioactive materials
Inorganic corrosives
Inorganic cyanides
Oxidizers
Effectiveness
Soil Sludge Sediments
V





V
V
V
a
a
a
a
a
a
a
T








a
a
a
a
a
a
a
V
V
V
T
•
V
V
V
V
a
a
a
a
a
a
a
• Demonstrated Effectiveness: Successful treatability test at
some scale completed
T Potential Effectiveness: Expert opinion thai technology will work
Q No Expected Effectiveness: Expert opinion that technology will not work
    The presence of detergents and emulsifiers can unfavorably
influence extraction performance and materials throughput.
Water-soluble detergents, found in some raw wastes (particularly
municipal), will  dissolve  and  retain organic pollutants in
competition with the extraction solvent. This can impede a
system's ability to achieve low concentration treatment levels.
Detergents and emulsifiers can promote the evolution of foam,
which  hinders separation and  settling characteristics  and
generally decreases materials throughput. Although methods
exist to combat these problems, they will add to the process
cost.

    When treated solids leave the extraction subsystem, traces
of extraction solvent will be present [8,  p. 125].  The typical
extraction solvents used in currently available systems either
volatilize quickly from the treated solids or biodegrade easily.
Ambient air monitoring can be employed to determine if the
volatilizing solvents present a problem.

    The types of organic  pollutants  that can be extracted
successfully depends, in part, on the nature of the extraction
solvent. Invariably, treatability tests should be conducted to
determine which solvent or  combination of solvents is  best
suited to the site-specific vagaries of a particular parameter/
matrix mix. In general, solvent extraction is least effective on
very high molecular weight organics and very hydrophilic
substances.

    Some commercially  available extraction  systems use
solvents that are  either flammable or mildly toxic or both [20,
p. 2]. However, there are long-standing  standard procedures
used by chemical companies, gasoline stations, etc.,  that can
be used to greatly reduce the potential for accidents.
                                                             Technology Description

                                                                  Figure 1  is a general schematic of the solvent extraction
                                                             process [3][15, p. 65][4, p. 3].

                                                                  Waste preparation (1) includes excavation and/or moving
                                                             the waste material to the process where it is normally screened
                                                             to remove debris and large objects.  Depending upon the
                                                             process vendor  and whether  the  process  is semibatch or
                                                             continuous, the waste may need to be made pumpable by the
                                                             addition of solvent or water.

                                                                  In the extractor (2), the waste and solvent mix, resulting in
                                                             the  organic contaminant  dissolving  into the solvent.  The
                                                             extraction behavior exhibited by this technology is typical of a
                                                             mass transfer controlled  process,  although  equilibrium
                                                             considerations often become limiting factors. It is important to
                                                             have a competent source conduct a laboratory-scale treatability
                                                             test to determine whether mass transfer or equilibrium will be
                                                             controlling. The controlling factor is critical to the design of the
                                                             unit and to the determination of whether the technology is
                                                             appropriate for the waste.

                                                                  The extracted organics are removed from the extractor
                                                             with the solvent and go to the separator (3), where the pressure
                                                          Engineering Bulletin: Solvent Extraction Treatment

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or temperature is changed, causing the organic contaminants
to separate from the solvent [9, p. 4-2].

    The  solvent is recycled (4)  to the extractor and the
concentrated contaminants (5) are removed from the separator
[11, P- 6].
Process Residuals

    There are three main product streams generated by this
technology: the concentrated contaminants, the treated soil or
sludge, and the separated water. The extract contains solvent-
free contaminants, concentrated into a smaller volume, for post
treatment.  The recovered contaminants may require analysis
to determine their suitability  for recycle, reuse, or further
treatment before disposal.

    The cleaned soil and solidsfrom treated sludge or sediments
may need to be dewatered, forming a dry solid and a separate
water stream. The volume of product water depends on the
inherent dewatering capability of the individual process, as well
as the process-specific requirements for feed slurrying. Since
the solvent is an organic material, some residue may remain in
the soil matrix. This can be mitigated by solvent selection, and
if necessary, an additional separation stage. Depending on the
extent of  metal or other inorganic contaminants, treatment of
the cleaned solids by some other technique (i.e., stabilization)
may be necessary.  Since the organic  component has been
separated, additional solids treatment should  be simplified.
The water  produced should be analyzed to  determine if
treatment is necessary before discharge.

    Solvent extraction  units are designed to  operate without
air emissions.  However, volatile air emissions could occur
during waste preparation.
Site Requirements

    Solvent extraction  units are transported by  trailers.
Therefore, adequate access roads are required to get the unit to
the site.  Typical commercial-scale units, 50-70 tons per day
(tpd), require a setup area of up to 3,600 square feet.

    Standard 440V three-phase electrical service is needed.
Water must be available at the site [3]. The quantity of water
needed is vendor and site specific.

    Contaminated soils or other waste materials are hazardous
and their handling requires that a site safety plan be developed
to provide for personnel protection and  special handling
measures.  Storage should be provided to hold the process
product streams until they have been tested to determine their
acceptability for disposal or release. Depending upon the site,
a method to store waste that has been prepared for treatment
may be necessary. Storage capacity will depend on waste
volume.

    Onsite analytical equipment for conducting oil and grease
analyses and a gas chromatograph capable of determining site-
specific organic compounds for performance assessment make
the operation more efficient and provide better information for
process control.
Performance Data

    The performance data currently available are mostly from
two vendors, CF Systems and Resource Conservation Company
(RCC).

    CF Systems' full-scale 50-tpd commercial unit (PCU 200),
which is treating refinery sludge at Port Arthur, Texas, meets or
                                        Figure 1.  Solvent Extraction Process
                                                                                      Treated Emissions

Organic 1
Contaminants '••^



— ^»~
                                                                                         Concentrated
                                                                                         Contaminants (5)

                                                                                         Solids
                                                                                         Water
                                                                                         Oversized Rejects
Engineering Bulletin: Solvent Extraction Treatment

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exceeds the EPA's Best Demonstrated Available Technology
(BOAT) standards for a number of organic contaminants (Table
3) [3].

                      Table 3
            API Separator Sludge Results*
             (Concentrations in mg/kg)
                                           Treated
                                         Products for
                        Feed      BDAT     Land
                    Concentrations  Target    Disposal

Benzene                   30.2        9.5    0.18
Toluene                   16.6        9.5    0.18
Ethylbenzene               30.4       67.0    0.23
Xylenes (Total)              13.2    Reserved    0.98
Anthracene                 28.3        6.2    0.12
Benzo(a)anthracene         BMDL**      1.4    0.18
Benzo(a)pyrene               1.9       0.84    0.33
Bis-(2-ethylhexy)phthalate      4.1       37.0    1.04
Chrysene                    6.3        2.2    0.69
Di-n-butyl phthalate         BMDL        4.2    0.11
Naphthalene               42.2    Reserved    0.66
Phenanthrene               28.6        7.7    1.01
Phenol                    BMDL        2.7   BMDL
Pyrene                      7.7        2.0    1.08

*  This information is from vendor-published literature;
   therefore, quality assurance has not been evaluated.
** Below Minimum Detection Limits (different values in Feed
   and Treated products).
Source: [3], CF Systems, 50 tpd
     Under the Superfund Innovative Technology Evaluation
(SITE) program, as shown in Table 4, CF Systems demonstrated
an overall PCB reduction of more than 90% for harbor sediments
with inlet concentrations up to 2,575 ppm [11, p. 6].

     A  mobile demonstration unit processed different feed
types including clay pit  material, ditch skimmer sludge, and
drainage basin soil. The wastes were contaminated with oil and
grease and aromatic priority pollutants.  The oil and grease
were separated  and their concentrations were reduced to
between 89% and 94%  of the original amount. For the most
part, the aromatic compounds were reduced to nondetectable
levels [6, p. 10].

     A treatability  study completed  at the  Conroe, Texas,
Superfund site with the mobile demonstration unit  showed
that polynuclear aromatic hydrocarbon (PAH) concentrations
in the soil were reduced 95% from 2,879 ppm to 122 ppm [12,
p. 3-12].

     The only available data for the on-line operational availability
were from CF Systems, which they estimated to be 85%
(corresponding to a treatment process downtime of 15%). This
can be verified and possibly improved with increased operating
experience.
       The ability of RCC's full- scale B.E.S.T.™ process to separate
   oily feedstock into product fractions was evaluated by the EPA
   at the General Refining Superfund site near Savannah, Georgia,
   in February 1987.   It is an abandoned waste oil re-refining
   facility that contained four acidic oily sludge ponds with high
   levels of heavy metals (Pb=200-10,000 ppm, Cu=83-l 90 ppm)
   and detectable PCBs (2.9-5 ppm). The average composition of
   the sludge from the four lagoons was 10% oil, 20% solids, and
   70% water by weight [16, p. 13]. The transportable 70 tons/
   day B.E.S.T.™ unit processed  approximately 3,700 tons  of
   sludge at the General Refining Site. The treated solids from this
   unit were back filled to the site, product oil was recycled as a fuel
   oil blend, and  the recovered  water was pH adjusted and
   transported to a local industrial wastewater treatment facility.

       Test results (Table 5) showed that the heavy metals were
   mostly concentrated in the solids product fraction.  TCLP test
   results showed heavy metals to  be in stable forms that resisted
   leaching,  illustrating a  potential  beneficial side  effect  when
   metals are treated by the process [1, p. 13].

       RCC  has bench-scale treatability data  on  a  variety  of
   wastes, including steel mill wastewater treatment sludge and
   oil refinery sludge (Table 6) [1, p. 12], that  will  illustrate the
   degree of separation  possible among the oil,  water, and solids
                           Table 4
            New Bedford Harbor Sediments Results
                   (Concentrations in ppm)



Test*
1
2
3


initial
PCB
Concentration
350
288
2,575


final
PCB
Concentration
8
47
200



Percent
Reduction
98
84
92
Number
of
Passes
Through
Extractor
9
1
6
     Source: [11 ], CF Systems, 1.5 gpm
                           Table 5
              EPA Data from the General Refining
                Superfund Site, Savannah, GA



Metals
As
Ba
Cr
Pb
Se

Initial
Concentration
(mg/kg)
<0.6
239
6.2
3,200
<4.0
Product
Solids
Metal
(ppm)
<5.0
410
21
23,000
<5.0

TCLP
Levels
(ppm)
<0.0
<0.03
<0.05
5.2
0.008
       Source: [1], RCC, 100 tpd
 4
Engineering Bulletin: Solvent Extraction Treatment

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components of the waste. The separation of PCBs in
contaminated harbor sediments is shown in Table 7 and in a
variety of matrices in Table 8. Results of treatment of pesticide-
contaminated soils are shown in Table 9.

    RCRA Land  Disposal Restrictions  (LDRs)  that require
treatment of wastes to BOAT levels prior to land disposal may
sometimes be determined to be applicable or relevant and
appropriate requirements (ARARs)for CERCLA response actions.
The solvent extraction technology can produce a treated waste
that meets treatment levels set by BOAT, but may not reach
these treatment levels in all cases. The ability to meet required
treatment levels is dependent upon the specific  waste
constituents  and the waste matrix.  In cases where solvent
extraction does not meet these levels, it still may, in certain
situations, be selected for use at the site if a treatability variance
establishing alternative treatment levels is obtained. EPA has
                        Table 6
               Oil and Grease Removal
                     Bench Scale
Original Sludge
Concentration
Oil%
Water %
Solids %
Product Stream
Oil
Water %
Solvent (ppm)
Water
Oil & Crease (ppm)
Solvent (ppm)
Solid
Oil & Crease (ppm)
Solvent (ppm)
Steel Mill
Sludge
11
33
56


<2
<100

<100
11

0.2
34
Refinery
Sludge
8
77
15


<1
<150

<100
12

0.9
N/A
     Source: RCC, 6 kg Batch
                        Table 7
                   Harbor Sediments
             PCB Extraction — Bench Scale
Original Sediments
Product Stream
Oil
Water
Solid
% Removal
4,500 ppm
75,000 ppm
10 ppb
<1 ppm
>99%
       Source: RCC, 6 kg Batch
made the treatability variance process available in  order to
ensure that LDRs do  not  unnecessarily restrict the use of
alternative and innovative treatment technologies. Treatability
variances may be justified for handling complex soil and debris
matrices. The following guides describe when and how to seek
a treatability variance for soil and debris: Superfund LDR Guide
#6A, "Obtaining a Soil and Debris Treatability Variance for
Remedial Actions" (OSWER Directive 9347.3-06FS) [17], and
Superfund  LDR Guide #6B, "Obtaining a  Soil and Debris
Treatability Variance for Removal Actions" (OSWER Directive
9347.3-07FS) [18]. Another approach could be to use other
treatment techniques in series with solvent extraction to obtain
desired treatment levels.
Technology Status

    During 1989, solvent extraction technology was selected
as the remedial action to clean up 2,000-2,200 cubic yards of
soil contaminated  with  PCBs and organics at  the Pinette
Salvage Superfund site in Washburn, Maine [13, p. 2]. In 1989,
solvent extraction was  also selected as the source control
remedy in the following Records of  Decision: F. O'Connor
Superfund site in Augusta, Maine; the Norwood PCBs Superfund
site in Norwood, Massachusetts; the Ewan Property Superfund
site in Shamong, New Jersey;  United Creosoting in Conroe,
Texas; and Outboard Marine, State of Illinois [19].

    The most significant factors influencing costs are the waste
volume, the number of extraction stages, and the operating
parameters such as labor, maintenance, setup, decontamination,
demobilization, and lost time  resulting from  equipment
operating delays. Extraction efficiency can be influenced by
process parameters such as solvent used, solvent/waste ratio,
throughput rate, extractor residence time, and  number of
extraction stages.  Thus, variation of these parameters  in a
particular hardware design and/or configuration will influence
the treatment unit  cost component,  but should not be a
significant contributor to the overall site costs.

    Cost estimates for this technology range from $100 to
$500 per ton.
Solvent Extraction Systems

    Solvent extraction  systems  are  at  various stages of
development. The following is a brief discussion of six systems
that have been identified.

    CF Systems uses  liquefied hydrocarbon  gases such as
propane  and  butane as solvents for separating organic
contaminants from soils, sludges, and sediments. The extraction
units are liquid-filled systems that employ pumps to move the
material through the system.  As such, the feed material is
pretreated,  through the addition of  water, to ensure the
"pumpability" of tne material [10, p. 12].  The pH of the feed
may be adjusted,  through the addition of lime or a similar
material, to maintain the metallurgical integrity of the system.
Typically, the feed material is screened to remove particles of
greater than 1 /8" diameter. Depending upon the nature of the
Engineering Bulletin: Solvent Extraction Treatment

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                                                      Tabled
                            PCB Samples Tested In RCC's Laboratory (1/87 through 7/98)
Client
SLUDGES
GRI
GRI
GRI
Superfund Site Sh
Superfund Site CO "A"
Superfund Site CO "B"
Superfund Site CO "C"
SEDIMENTS
River Sediment "B"
Superfund B (#1 3)
Harbor Sediment "B"
Harbor Sediment "C"
Harbor Sediment "D"
Harbor Sediment NB-A
Harbor Sediment NB-B
SOILS
Industrial Soil A
Industrial Soil B
Industrial Soil D
Industrial Soil j
As Received
PCB
(mg/kg)

5.9
4.7
5.3
106
51
21
11

960
83
20,000
30,000
430
5,800
16,500

250
120
5,300
19
Raw Sample Phase Composition
Oil % Water % Solids %

27 66 7
10 58 32
13 57 30
35 44 21
49 28 23
23 24 53
15 16 69

26 17 83
44 40 16
3 22 75
5.6 62 32
0.38 47 53
1.9 69 29
4.3 51.6 44.1

0.06 9.4 91
0.06 1 3 87
1.0 19 80
.09 16 84
PCBs in Product fraction
Oil Water Solids % Removal
(mg/kg) (mgAg) (mg/kg)

9.3 <.005 <.01 99.9%
N/A <.01 0.015 99.9%
N/A <.01 0.14 99.2%
270 N/A 1.0 99.8%
80 N/A 0.44 99.8%
71 N/A 0.08 99.8%
52 N/A 0.06 99.6%

N/A N/A 40 96.5%
N/A N/A 1.0 99.8%
970,000 <.006 27 99.9%
550,000 N/A 94 99.9%
N/A N/A 32 96.0%
280,000 <.005 35 99.4%
360,000 <.005 75 99.8%

120,000 N/A 2.2 99.1%
280,000 N/A 6.4 94.7%
370,000 N/A 11 99.8%
10,000 N/A 0.7 96.3%
    Source: RCC, .6 kg Batch
oversize material, the large particles may be reduced in size and
then returned to the extraction unit for processing.

    CF Systems' extraction technology has been demonstrated
in the field at two Superfund sites and approximately 10
refineries and treatment, storage, and disposal (TSD) facilities
to date.

    CF Systems' solvent extraction technology is available in
several commercial sizes and the Mobile Demonstration Unit is
available for onsite treatability studies. To date, CF Systems has
supplied  three commercial-scale extraction units for the
treatment of a variety of wastes [12, p.  3-12].  A 60-tpd
treatment system was designed to extract organic liquids from
a broad range of hazardous waste feeds at ENSCO's El Dorado,
Arkansas, incinerator facility.   A commercial-scale extraction
unit is being installed at a facility in Baltimore, Maryland,  to
remove organic contaminants from a 20-gpm wastewater
stream. A PCU-200 extraction unit is installed and operating at
the Star Enterprise (Texaco) refinery in Port Arthur, Texas. This
unit is designed to treat listed refinery wastes to meet or exceed
the EPA's BOAT standards. Performance data and the technology
status are explained in the body of this bulletin.
    RCC's B.E.S.T.™ system uses aliphatic amines (typically
triethylamine)  as  the solvent to separate  and  recover
contaminants [1, p. 2]. It is applicable to soils, sludges, and
sediments, and in batch mode of operation does not need a
pumpable waste. Before the extraction process is begun, feed
materials are screened to remove particles of greater than 1"
diameter and pH adjusted to an alkaline condition. The process
operates at or near  ambient temperature and pressure.
Triethylamine can be recycled from the recovered liquid phases
via steam stripping because of its high vapor pressure and low
boiling point azeotrope formation.

    RCC has a transportable B.E.S.T.™ pilot-scale unit available
to treat soils and sludges. This pilot-scale equipment has been
used at a gulf coast  refinery treating  various refinery  waste
streams and has treated PCB-contaminated soils at an industrial
site in Ohio in November 1989. A full-scale unit with a nominal
capacity of 70 tpd  was used to clean up  3,700 tons of PCB-
contaminated petroleum  sludge  at  the General  Refining
Superfund Site in Savannah, Georgia, in 1987. Performance
data and the technology status are explained in the body of this
bulletin.
                                                         Engineering Bulletin: Solvent Extraction Treatment

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    ENSR is in the process of developing a mobile solvent
extraction unit capable of decontaminating soils and sludges at
a rate of 5 to 10 cubic yards/hour [5, p. 1 ]. The ENSR system
uses a proprietary reagent and solvent. The company claims
that its solvent extraction system is designed to operate without
significant pretreatment of the  soil/sludge and without the
addition or removal of water. Design of a pilot-scale unit is near
completion.   Thus far, only performance data from earlier
bench-scale tests  are available.

    The Extraksol™ process was developed in 1984 by Sanivan
Group, Montreal, Canada  [7, p. 35].  It is  applicable to soils,
sludges, and sediments. Performance data on contaminated
soils and refinery wastes are available for a 1 ton per hour (tph)
mobile unit. The process uses a proprietary solvent  that
reportedly achieved removal efficiencies up to 99% (depending
on the number of extraction cycles and the type  of soil) on
PCBs, oil, grease, PAHs, and pentachlorophenol [7, p. 45]. The
1 -tph unit is suitable for small projects with  a maximum of 300
tons of material to be treated. The Sanivan group is planning
to build a full-scale unit that can process 6-8 tph of waste [7, p.
41].

    Harmon  Environmental  Services  and Acurex
Corporation are  involved in a  cooperative joint venture to
develop a solvent soil washer/extraction system appropriate for
the onsite remediation of Superfund and RCRA sites. They have
completed EPA-sponsored bench-scale studies on different
types of soils contaminated with #2 fuel oil. The design of a pilot
plant unit is being considered.
    The Low Energy Extraction Process (LEEP) is a patented
solvent  extraction process that can  be used onsite for
decontaminating soils, sludges, and sediments.  LEEP uses
common hydrophilic and hydrophobic organic solvents to
extract and further concentrate organic pollutants such as PCBs
[2, p. 3].  Bench-scale studies are available. The design of the
pilot plant is completed, and the plant is scheduled for operation
at the beginning of 1990.
EPA Contact

    Technology-specific questions regarding solvent extraction
may be directed to:

    Michael Gruenfeld
    U.S. EPA,  Risk Reduction Engineering Laboratory
    GSA Raritan Depot
    Wood bridge Avenue
    Edison, New Jersey 08837
    FTS 340-6625
    (201)321-6625
                       Table 9
           RCC B.E.S.T.™ Treated Pesticide-
          Contaminated Soil — Bench Scale
Anolyte
p,p'-DDT
p,p'-DDE
p,p'-DDD
Endosulfan-l
Endosulfan-ll
Endrin
Dieldrin
Toxaphene
BHC-Beta
BHC-Camma
(Lindane)
Pentachlorophenol
Feedstock
(ppm)
500
84
190
250
140
140
37
2,600
<30

<30
150
Product
Solids
(ppm)
0.2
0.5
0.05
<0.02
<0.02
0.02
<0.02
0.9
<0.13

<0.07
1.9
Removal
Efficiency %
99.96
99.4
99.97
>99.99
>99.99
99.99
>99.95
99.97
-

-
98.7
                                                            3.

                                                            4.
 Source: RCC, .6 kg Batch
                 REFERENCES
     Austin, Douglas A.  The B.E.S.T.™ Process — An
     Innovative and Demonstrated Process for Treating
     Hazardous Sludges and Contaminated Soils. Presented
     at 81st Annual Meeting of APCA, Preprint 88-6B.7,
     Dallas, Texas, 1988.
     Blank, Z., B. Rugg,  and W. Steiner. LEEP-Low Energy
     Extraction Process:  New Technology to Decontaminate
     PCB-Contaminated Sites, EPA SITE E02 Emerging
     Technologies Program. Applied Remediation
     Technology, Inc., Randolph, New Jersey, 1989.
     CF Systems Corporation, Marketing Brochures (no
     dates).
     Hall, Dorothy W., J.A. Sandrin, R.E. McBride. An
     Overview of Solvent Extraction Treatment
     Technologies. Presented at AICHE Meeting,
     Philadelphia, Pennsylvania, 1989.
     Massey, M.)., and S. Darian.  ENSR Process for the
     Extractive Decontamination of Soils and Sludges.
     Presented at the PCB Forum,  International Conference
     for the Remediation of PCB Contamination,  Houston,
     Texas, 1989.
Engineering Bulletin: Solvent Extraction Treatment

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                                               REFERENCES
6.   Moses, John M., R. Abrishamian. Use of Liquified Gas
     Solvent Extraction in Hazardous Waste Site Closures.
     Presentation Paper No. 55D, Presented at AICHE
     Summer National Meeting, Denver, Colorado, 1988.
7.   Paquin,)., and D. Mourato.  Soil Decontamination with
     Extraksol. Sanivan Croup, Montreal, Canada (no date),
     pp. 35-47.
8.   Reilly, T.R., S. Sundaresan, and J.H. Highland. Cleanup
     of PCB Contaminated Soils and Sludges By A Solvent
     Extraction Process: A Case Study. Studies in
     Environmental Science, 29: 125-139, 1986.
9.   Rowe,  G. Evaluation of Treatment Technologies  for
     Listed Petroleum Refinery Wastes, Chapter 4. API
     Waste Technologies Task Force, Washington, DC,
     1987.  pp. 1-12.
10.  Technology Evaluation Report — CF Systems Organics
     Extraction System, New Bedford, MA, Volume I.
     Report to be published, U.S.  Environmental Protection
     Agency.
11.  Technology Evaluation Report — CF Systems Organics
     Extraction System, New Bedford, MA, Volume II.
     Report to be published, U.S. Environmental Protection
     Agency.
12.  Applications Analysis Report — CF Systems Organics
     Extraction System, New Bedford, MA, Report to be
     published, U.S. Environmental Protection Agency.
13.  Innovative Technology: B.E.S.T.™ Solvent Extraction
     Process. OSWER Directive 9200.5-253FS, U.S.
     Environmental Protection Agency, 1989.
                14.  Raghavan, R., D.H. Dietz, and E. Coles. Cleaning
                     Excavated Soil Using Extraction Agents: A State-of-the-
                     art Review.  EPA 600/2-89/034, U.S. Environmental
                     Protection Agency, Releases Control Branch, Edison, NJ,
                     1988.
                15.  Technology Screening Guide for Treatment of CERCLA
                     Soils and Sludges.  EPA/540/2-88/004, U.S.
                     Environmental Protection Agency, 1988.
                16.  Evaluation of the B.E.S.T.™ Solvent  Extraction Sludge
                     Treatment Technology Twenty-Four Hour Test. EPA/
                     600/2-88/051, U.S. Environmental Protection Agency,
                     1988.
                17.  Superfund LDR Guide #6A: Obtaining a Soil and Debris
                     Treatability Variance for Remedial Actions. OSWER
                     Directive 9347.3-06FS, U.S. Environmental Protection
                     Agency, 1989.
                18.  Superfund LDR Guide #6B: Obtaining a Soil and Debris
                     Treatability Variance for Removal Actions.  OSWER
                     Directive 9347.3-07FS, U.S. Environmental Protection
                     Agency, 1989.
                19.  ROD Annual Report, FY 1989. EPA/540/8-90/006, U.S.
                     Environmental Protection Agency, 1990.
                20.  Weimer, L.D. The B.E.S.T.™ Solvent Extraction Process
                     Applications with Hazardous Sludges, Soils and
                     Sediments.  Presented at the Third International
                     Conference, New Frontiers for Hazardous Waste
                     Management, Pittsburgh, Pennsylvania, 1989.
                                        * U.S. GOVERNMENT PRINTING OFFICE 1990-0-726-081
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  Environmental Protection
  Agency
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Information
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