United States
                  Environmental Protection
                  Agency         	
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
                  Research and Development
EPA/600/S2-88/051 Nov. 1988
&EPA         Project  Summary

                   Evaluation  of the  B.E.S.TJM
                   Solvent  Extraction  Sludge
                   Treatment  Technology
                   Twenty-Four Hour  Test
                   Gerard W. Sudell
                     A  twenty-four hour sampling
                  and analytical effort was conducted
                  on Resources  Conservation Co.'s
                  Solvent Extraction Sludge Treatment
                  Technology  prototype full-scale
                  commercial facility while operating at
                  the General Refining Superfund  site
                  in Garden City, Georgia. The site  was
                  contaminated  with oily  residues
                  resulting from waste oil rerefining
                  and reclamation operations.  The
                  B.E.S.T.™* sludge treatment tech-
                  nology was tested to determine its
                  suitability for application as a trans-
                  portable on-site treatment  technol-
                  ogy for spill and waste site cleanups,
                  with   special  potential  for oily
                  hazardous waste materials. The
                  process separates oily sludges  into
                  their  component oil, solids,  and
                  water  fractions, and conditions them
                  for disposal or for further treatment
                     The test  data  confirm  the
                  system's capability to  separate  the
                  sludges  as predicted,  often in
                  efficiencies of over 98%. Comparison
                  of laboratory  simulation data to field
                  data indicates that laboratory-scale
                  simulations can be useful  in pre-
                  dicting system performance.
                     This  Project  Summary was
                  developed  by EPA's  Risk Reduction
                  Engineering  Laboratory, Cincinnati,
                  OH, to announce key findings of the
                   "Mention of trade names or commercial products
                   does not constitute endorsement or recom-
                   mendation for use
data   evaluation,  which  are
documented in the report.

Introduction
    B.E.S.T.™ solvent extraction sludge
treatment technology data  were
generated during a twenty-four  hour
performance  test conducted  at the
General Refining  site in Garden  City,
Georgia. The test  was conducted by the
Resources Conservation  Co.  (RCC) with
the assistance  of  EPA's  Region  X
Environmental Services Division  in
cooperation with EPA's Region  IV
Emergency  Response  and  Control
Branch.
    The General  Refining site,  located
near Savannah, Georgia, was operated  as
a waste oil reclamation  and  rerefining
facility from the early 1950s until 1975.
Sulfuric acid used to treat the waste  oil
produced  an acidic  oily  sludge, while
process filtration produced an oily filter
cake  by-product.  The sludge  was
disposed of in four unlined lagoons, and
the filter cake was buried and stockpiled
on-site. An additional unlined  lagoon
that had  been used as an oil-water
separator was backfilled  with filter  cake
and sludge, and waste oil was stored in
bulk tanks on-site.
    To remedy the situation, site cleanup
actions were initiated in  the  summer  of
1986 to stabilize  the site, secure the
facility, and explore disposal alternatives.
In  evaluating  disposal  alternatives,
consideration was given  to on-site and
off-site incineration, landfilling, and on-
site solvent extraction. The  B E.S.T.™

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solvent extraction process was chosen as
the most suitable  and  cost-effective
option.
    In  mid-1986  RCC  mobilized and
installed  its  prototype  full-scale
commercial solvent extraction sludge
treatment system at the General Refining
site. After shakedown and modification of
the prototype 100 ton/day system,
approximately 3,700 tons of oily sludges
from the petroleum  rerefining operations
were  treated.  The  B.E.S.T.™ system
operation concluded in March 1987.
    The  initial sampling  and analytical
activity  conducted during the  removal
operation was directed  at verifying the
composition of the product streams. RCC
previously  had  evaluated  petroleum
industry sludges at the laboratory-scale
level.  These efforts  resulted  in data that
tracked the isolation of contaminants into
the oil,  water, and  solids fractions, and
also determined  EP toxicity  and  TCLP
results  for the  solids  residues. The
General Refining operation provided the
opportunity to  compare a prototype full-
scale  commercial facility's data with the
laboratory-scale  data for treatment  of
hazardous waste sludges.
    RCC, in cooperation  with EPA's
Region  X,  then  developed  and imple-
mented  a  twenty-four  hour sampling
and analysis  project  to  evaluate the
system's performance and  efficiency
both in  the separation of the feed  com-
ponents  and  in the  isolation  of  con-
taminants into specific product streams.
    The Technology Evaluation  report is
divided  into six  sections: introduction;
summary and conclusion outlining the
performance of the technology during the
sampling effort; brief description of the
General Refining site; description  of the
technology;  discussion of the system
operation and  data  collected during the
test period; and quality assurance/quality
control.
    The General Refining site was used
from the early 1950s to 1975 as a waste
oil reclamation and rerefining facility. The
site is  located off  Route 80, Chatham
County, in Garden City, Georgia, west of
Savannah.  The total  volume  of  waste
generated was estimated to be in excess
of 10,000 tons. Analysis of the waste  oil,
sludge,  and filter cake  performed  during
an  early material characterization  phase
of  the  RCC  project  revealed  the
presence  of  petroleum compounds,
heavy metals including lead  and copper,
PCBs, and low-pH sludges and water.
    Composition of  the sludges  and soils
at the site varied widely from point to
point laterally and  vertically within the
lagoons. Nominal composition in weight
percent was approximately 10% oil, 70%
water, and 20% solids, but during actual
operation oil ranged  from 0-40%, water
from  60-100%,  and  solids  from  2-
30%.  During  the  twenty-four hour test
period  the feed was fairly consistent at
27% oil, 66%  water,  and  7%  solids.
Primary contaminants in  the feed were
PCBs ranging  from 1 to  13  mg/kg, and
lead ranging from 2200 to 7400 ppm.
    The  sludge at  the  site  exhibited
some unusual physical properties. The
untreated  sludge  formed an  emulsion
that was hydrophobic and could  not  be
mixed  with  water.  The sludge was
determined to be  rheopectic,  since
mixing acted to increase its  viscosity,
changing it from a paste-like state to a
semi-solid.  Viscosity  readings  on
several samples ranged from 490,000 to
530,000 centipoise Brookfield.
    The site  remediation  involved
neutralizing the sludge from  the lagoons
and  then processing it through  the
B.E.S.T.™ solvent  extraction system
where it was separated into its  oil, water,
and solids product fractions. Some of the
product oil was transported  off-site with
the  remainder  stored on-site  for
treatment by other methods;  the product
water was first treated on-site  and then
transported  to  a  nearby  industrial
wastewater treatment system; and the
product solids were stored on-site.

Procedure
    The  RCC.'s   prototype full-scale
commercial  facility  has  a  nominal
capacity of 100 ton/day wet throughput.
The system is modular, is  capable of
being transported to contaminated sites
for operation and cleanup, and  offers the
capability to include all required on-site
utilities except for electricity  and  potable
water.
    The  B.E.S.T.  M sludge treatment
system  processes difficult-to-treat
emulsified oily sludges by breaking the
emulsion and  physically separating the
sludge  into three  separate fractions.
These fractions-oil, water,  and sol-
ids-then  can be handled  separately.
As  the  fraction separations  take place,
certain  contaminants can be  removed
from  the  original  sludge  and  con-
centrated  into a  specific  phase;  for
example  PCBs  concentrate  in  the
product oil fraction,  and metals  in the
product solids  fraction. This separation
permits  a determination of the  most
appropriate methods for disposal  and the
suitability  for recycling or reuse  of the
separated fractions.
    The process uses one or more of a
family of aliphatic  amine  solvents to
break oil/water emulsions  and  rele
bonded water from  the sludge.
solvent used at the General Refining
triethylamine (TEA), becomes comple
miscible with  water when cooled b<
20°C, but upon  heating becor
immiscible. The process mixes rel
erated TEA solvent with the oily  slud
releasing  solids  from  the  oil/w<
emulsion.  The solids are  removed
centrifugation and  dried.  Solvent
separated from the oil and water fracti
using distillation techniques.
    The oil product fraction is chemic
unaltered  by   the process  and  has
same characteristics as the feed mate
The objective is to recover and reuse
fraction as a  fuel or process feedstc
The   water  product fraction,  whi
volume increases by approximately  2
due  to steam condensation within
system,   is able  to be treated  <
discharged. The solids residual is pow
dry and contains only traces of the oil.
    Sludge feed limitations are prime
large  particle  size and reactivity with
process solvent.  Process  performai
can be influenced by feed characteris
such  as the presence of detergents ;
emulsifiers,   or of low-pH mater
Detergents can result in degraded  s
aration efficiency resulting in increa;
concentrations of oil and grease in
product  water,  and increased wa
content  in the product  oil.   Emulsifi
can affect organics separation from
water fraction. Low  pH material must
neutralized to  prevent reactions with ;
loss of the solvent.
    During  operations  at the   si
preprocessing treatment consisted
screening the filter cake and  bacl
material through a  1/4-inch  hammern
which crushed the material to the s
desired for processing.  Sludge from
ponds, often  in  excess of 1,000,C
centipoises, was pumped into a vibrat
screen and placed  into  storage tanks
await processing. Since  the sludge v
highly acidic,  it was neutralized  w
sodium   hydroxide.  A feedrate
approximately  40 ton/day was maintair
during the test  period.  The  oil  prod
was  discharged into  an oil  polisher
further separate water from the  oil, I
solids were discharged from the sol
dryer through  an exit chute into  stora
containers, and  the water  was furtt
processed  in an  on-site  treatrm
system.
    Posttreatment  requirements  for 1
separated  fractions  vary  betwe
applications. Some  product oil, water,
solids  upgrading  may  be  need
depending on  the intended disposition

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these  materials.  For example, if  the
solids are to be landfilled, some further
treatment  such  as fixation  may  be
required. PCBs can  be isolated in the oil
fraction and either can be chemically or
thermally  destroyed by  subsequent
treatment or used as fuel if the  PCS
contamination is within regulatory limits.
    The  product  water is treated in  an
on-site water  treatment  plant  prior  to
discharge. The water treatment plant is a
modular facility   using  two-stage
clarification.  The  first stage consists of
acidifying  the water  and adding  a
flocculent and an  oil/water emulsion
breaker. Then  lime is added to raise the
pH and aid in precipitating lead (Pb), and
a contact clarifier is used  to settle out
sludge materials.
    The  B.E.S.T.™ sludge  treatment
process is  operated  with the use of  an
automatic control  system that monitors
process conditions  and  makes  process
adjustments  as  required.  A process
operator monitors  the control system and
makes additional  adjustments. Samples
of the feed and  product streams  are
collected periodically and  analyzed  to
ensure proper system operation.
    Since the  General Refining site was
an inactive  site,  RCC was  required  to
supply all necessary utilities other than
electricity  and  service  water.  RCC
provided a  mobile  oil-fired  boiler for
steam  generation, a cooling tower for
cooling water,  a cryogenic nitrogen (Na)
storage  system,  a water  product
treatment facility,  and instrumentation  air
for process equipment operation.

Results and Discussion
    The  B.E.S.T.™  solvent extraction
sludge treatment  100 ton/day prototype
commercial facility operation  at  the
General Refining  site demonstrated the
system's  capability to  separate oily
feedstock into its oil, water, and  solids
product  fractions and to  concentrate
certain  contaminants into  a specific
product fraction. Separation  efficiencies,
defined as the amount of desired product
less the amount of all undesired products
times 100, often  exceeded 98%. The
solids  product stream  was  shown  to
contain  less than 0.5%   moisture, with
very  little  oil  contamination;  the  oil
product contained  only 0.88% water; and
the water product  contained 0.0033%  oil
and less than .81 % total solids.
    After separation, the streams were
analyzed for contaminant concentrations
to ascertain  that  specific  key con-
taminants had concentrated preferentially
into  a particular  product  fraction. The
contaminants  of  interest were  PCBs,
lead, metals, volatiles, semivolatiles, and
chlorinated dioxins and furans. In general
the PCBs, volatiles, and semivolatiles
concentrated in the oil fraction, with little
contamination  found m  the  solids  and
water product fractions.  Metals mostly
concentrated  in the  solids fraction, but
lead concentrated into both the solid and
oil fractions, suggesting  that lead  m the
sludge feed was bound  inorganically as
well  as organically   Chlorinated dioxins
and furans were below detection limits  in
the  raw  sludge  feed.   On-site  water
treatment reduced most  levels of
contaminants in  the discharged treated
product  water, maintaining  about the
same  semivolatiles concentrations,
slightly reduced volatiles, and  signifi-
cantly reduced metals concentrations.

Conclusions and
Recommendations
    The General Refining operation was
the first full-scale test of the  B.E.S.T.™
sludge treatment  technology. The data
indicate  the  system's  capability to
separate  oily sludges as predicted,  in
efficiencies of over 98%,  and to produce
disposable product  streams. In  addition,
comparisons of laboratory simulation
data  to  field  data  indicate  that
laboratory-scale  simulations  can be
useful in  predicting system performance.
Although  the current data confirm the
system's  capability to perform as
designed,  further  testing over an
extended period  of time  should be
undertaken when the system is operating
at another site. Testing  over a longer
period of time can aid in the  affirmation
of the effectiveness of the process and  in
the development of  operating and cost
data.
    The  full  report was submitted  in
partial  fulfillment  of Contract  No. 68-
03-3255  by Enviresponse, Inc.,  under
sponsorship of the  U.S. Environmental
Protection Agency.

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  Gerard W. Sudell is with Enviresponse, Inc., Edison, NJ 08837
  Mary K. St/nson is the EPA Project Officer (see below).
  The complete report,  entitled "Evaluation of the B.E.S.T.™ Solvent  Extraction
       Sludge  Treatment Technology Twenty-Four Hour Test," (Order No. PB
       88-245 9071 AS;  Cost: $19.95, subject to change) will be available only
       from:
           National Technical Information Service
           5285 Port Royal Road
           Springfield, VA22161
           Telephone:   703-487-4650
  The EPA Project Officer can be contacted at:
           Risk Reduction Engineering Laboratory
           U.S. Environmental Protection Agency
           Edison, NJ 08837
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
     BULK RATE
POSTAGE & FEES PAID
         EPA
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Official Business
Penalty for Private Use $300

EPA/600/S2-88/051
               0001961   HWER

               L|8|ARY REGION  V
               U5  EPA

                                     ST
                                        IL   60604

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