EPA/540/R-94/514
                                            July 1995
         TEXACO GASIFICATION PROCESS

   INNOVATIVE TECHNOLOGY EVALUATION REPORT
NATIONAL RISK MANGEMENT RESEARCH LABORATORY
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S. ENVIRONMENTAL PROTECTION AGENCY
             CINCINNATI, OHIO 45268
                                       Printed on Recycled Paper

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                                            NOTICE
     The information in this document has been prepared for the U.S. Environmental Protection Agency (EPA)
Super-fund Innovative Technology Evaluation (SITE) Program under Contract No. 68-C9-0033. This document
has been subjected to EPA's peer and administrative reviews and has  been approved for publication as an  EPA
document.  Mention  of trade  names or commercial products does  not constitute an  endorsement or
recommendation for  use.

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                                                FOREWORD
      The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and water
resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading
to a compatible balance between human activities and the ability of natural systems to support and nurture life.  To meet
these mandates, EPA's research program is providing data and technical support for solving environmental problems today
and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants
affect our health, and prevent or reduce environmental risks in the  future.

      The National Risk Management Research Laboratory is the  Agency's center for investigation of technological and
management approaches for reducing risks from threats  to human health and the  environment.   The focus of the Laboratory's
research program is on methods for the prevention and  control of pollution to air, land, water and subsurface resources;
protection  of water quality in public water systems ;  remediation of contaminated  sites and groundwater; and  prevention and
control of  indoor air pollution.  The goal of this research effort is to catalyze development and implementation of innovative,
cost-effective environmental technologies; develop scientific and engineering information needed by EPA to support
regulatory and policy decisions; and provide technical support and information transfer to ensure effective implementation
of environmental regulations and strategies.

      This publication has been produced as  part of the  Laboratory's strategic  long-term research plan.  It is published and
made available by EPA's Office of Research and Development to assist the user  community and to link researchers with their
clients.
                                                   E. Timothy Oppelt, Director
                                                   National Risk Management Research Laboratory

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                                           CONTENTS
                                                                                              Page

 Notice	        ii
 Fore ward  	        iii
 Figures  	        vil
 Tables  	        vil
 List of Abbreviations, Acronyms, and  Symbols  	       viil
 Conversion  Factors  	        x
Acknowledgements  	         xl

 Executive Summary  	        1

 1   Introduction   	        7
    1.1    Background  	        7
    1.2    Brief Description of Program  and Reports  	        8
    1.3    Purpose of the Innovative Technology Evaluation Report (ITER)  	        10
    1.4    Technology  Description   	       10
    1.5    Key Contacts  	       27
2   Technology Applications Analysis    	       29
    2.1    Objectives  -  Performances versus ARARs    	       29
         2.1.1    Comprehensive  Environmental  Response,  Compensation,
                  and Liability Act  	        30
         2.1.2    Resource  Conservation and  Recovery Act  	        36
         2.1.3    Clean Air Act 	       37
         2.1.4    Safe  Drinking Water Act   	       37
         2.15    Clean Water  Act   	       38
         2.1.6    Toxic Substances Control Act  	       38
         2.1.7    Occupational  Safety and  Health  Administration  Requirements	        39
    2.2    Operability  of the  Technology 	       40
    2.3    Applicable Waste 	       42
    2.4    Key Features  	       43
    2.5    Availability and Transportability of Equipment   	'	       44
    2.6    Materials  Handling Requirements   	       45
    2.7    Site Support Requirements  	       45
    2.8    Limitations  of the  Technology 	       46
3   Economic  Analysis   	        47
    3.1    Conclusion of Economic  Analysis   	       47
    3.2    Basis of Economic Analysis   	       49
    3.3    Issues  and Assumptions   	       50
    34    Results  	       51
         3.4.1    Site Preparation Costs   	       51
         3.4.2    Permitting  and  Regulatory  Requirements   	       52

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                                  CONTENTS  (Continued)


                                                                                           Page


         3.4.3   Capital Equipment  	       52
         3.4.4   Startup  	       53
         3.4.5   Labor  	       54
         3.4.6   Consumables  and Supplies  	       54
         3.4.7   Utilities  	       54
         3.4.8   Effluent Treatment and  Disposal   	       54
         3.4.9   Residual Waste  Shipping and Handling  	        55
         3.4.10  Analytical Services  	       55
         3.4.11   Maintenance and Modifications  	        55
         3.4.12  Demobilization   	       55
4   Treatment  Effectiveness	       56
    4.1    Introduction	  	       56
    4.2    DRE   	       58
    4.3    Slag and Solid  Residuals Leachability   	       59
         4.3.1   Test Slurry Leaching  Characteristics  	        59
         4.3.2   SITE  Demonstration  Results   	       62
    4.4    Synthesis Gas Product	         63
         4.4.1   Synthesis  Gas Composition  	        63
         4.4.2   Products of Incomplete Reaction (PIRs)   	       63
         4.4.3   Particulate Emissions   	       65
         4.4.4   Acid Gas  Removal   	       65
    4.5    Metals Partitioning  	       66
    4.6    Process Wastewater  	         67
5   Other Technology  Requirements  	       69
    5.1  Environmental Regulation Requirements  	         69
    5.2    Personnellssues  	         69
    5.3   Community  Acceptance  	         70
6   Technology Status   	        7"!
    6.1    Petroleum  Production Tank Bottoms  Demonstration  	       71
    6.2    El  Dorado,  Kansas Refinery Project  	  	       71

Appendices

I Vendor Claims  	      72
II  Case  Studies 	       78
                                                VI

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                                          FIGURES
Number

  1-1
  1-2
  1-3
  1-4
  1-5
 Block Flow Diagram of MRL TOP during SITE Demonstration ....
 Solids Grinding and Slurry Preparation  Unit Process Flow Diagram
 High Pressure Solids Gasification Unit  Process Flow Diagram  ..  .
 Acid Gas Removal Unit  Process  Flow  Diagram   	
 Sulfur Removal Unit Process Flow Diagram  	
Page

   12
   13
   16
   21
   23
                                           TABLES
Number

  ES-I
  2-I
  3-I
  3-2
  4-I
  4-2

  4-3
  4-4
  4-5

  1-1
  I-2
  11-1
 Evaluation Criteria for the Texaco Gasification Process Technology   	
 Federal and State ARARs  for the Texaco Gasification  Process Technology
 Treatment Costs Associated with  the TCP
 Capital  Costs for the TCP Unit
 Composition of Demonstration Slurry Feed
 Destruction and Removal Efficiencies (DREs) for Principal Organic Hazardous
Constituent (POHC) - Chlorobenzene
 TCLP and WET-STLC Results - Lead and Barium
 Synthesis Gas  Composition
 Mass Flow Rates  and Total Concentrations of Lead and Barium in Slurry
Feed and Solid Residuals	•.	
 Syngas Composition Data-On-Line Analysis
 Mass Flow Rates of Lead and Barium in Slurry Feed and Solid Residuals  	
 Raw Syngas Composition and Heating  Value
    4
   31
   48
   53
   58

   60
   61
   64

   67
   74
   75
   80
                                               VII

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                LIST OF ABBREVIATIONS, ACRONYMS, AND SYMBOLS
ACL           alternate concentration limit
Ar             argon
ARAR         Applicable  or Relevant and Appropriate Requirements
ATTIC         Alternative  Treatment  Technology  Information Center
Ba             barium
Btu            British thermal unit
CAA           Clean Air Act
CAL/EPA      California Environmental Protection Agency
CCR           California Code of Regulations
CERCLA       Comprehensive Environmental Response,  Compensation, and  Liability Act
CERI           Center for Environmental Research Information
CFR           Code  of Federal  Regulations
CH4           methane
C O           carbon monoxide
CO2           carbon dioxide
COS         carbonyl sulfide
cu             cubic
CWA          Clean Water Act
DOT           Department of  Transportation
DRE           destruction and removal efficiency
dscf           dry standard  cubic feet
EPA           United  States Environmental  Protection Agency
ฐF             degrees Fahrenheit
FS             feasibility study
ft             feet
FWEI          Foster Wheeler  Enviresponse,  Incorporated
FWQC         Federal  Water Quality Criteria
gpm           gallons per minute
gr             grains
H2             hydrogen
HPSGU        High Pressure Solids  Gasification Unit
H2S           hydrogen sulfide
h              hour
ITER           Innovative  Technology  Evaluation  Report
kg             kilogram
kWh           kilowatt hour
L             liter
Ib             pounds
LPSGU        Low  Pressure Solids Gasification Unit
m3             cubic meter
MCL           maximum  contaminant level
mg            milligram
                                               VIII

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         LIST OF  ABBREVIATIONS, ACRONYMS, AND SYMBOLS (Continued)
min            minute
MRL           Montebello  Research Laboratory
N2             nitrogen
NAAQS        National Ambient Air Quality Standards
NO,            nitrogen oxide
NPDES        National Pollutant  Discharge Elimination System
NTIS           National Technical  Information System
ORD           Office of Research and Development
OSHA         Occupational Safety  and  Health Administration
OSWER        Office of Solid  Waste and Emergency Response
Pb             lead
PCB           polychlorinated   biphenyl
PCDD         polychlorinated   dibenzodioxin
PCDF          polychlorinated   dibenzofuran
PIR            product  of incomplete reaction
POHC         principal organic hazardous  constituent
PPE           personal  protective equipment
ppm           parts per million
ppmv          parts per million, by volume
ppq            parts per quadrillion
PSD           prevention of significant deterioration
psig            pounds per square inch gauge
RCRA         Resource Conservation and  Recovery Act
SARA          Superfund  Amendments and  Reauthorization  Act
SCAQMD       South Coast Air Quality Management District
SDWA         Safe Drinking Water Act
s              second
SITE           Superfund  Innovative Technology  Evaluation
SOX            sulfur oxide
svoc         semivolatile  organic  compound
TCLP          Toxicity  Characteristic Leaching Procedure
TOP           Texaco  Gasification  Process
THC           total hydrocarbons
tpd             tons per day
TSCA          Toxic Substances Control Act
TSD           treatment,  storage,  and  disposal
VISITT         Vendor Information System for Innovative Treatment Technologies
V O C          volatile organic compound
WET-STLC     Waste  Extraction Test-Soluble Threshold Limit Concentration
WWTU         wastewater treatment unit
yd             yard
                                             IX

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CONVERSION FACTORS

Length
Area:
Volume:

Mass:


Pressure:

Energy:

Temperature:
English (US)
1 foot (ft)
1 square foot (ft2)
1 gallon (gal)
1 cubic foot (ft3)
1 grain (gr)
1 pound (Ib)
1 ton (t)
1 pound per square inch (psi)
1 pound per square inch (psi)
1 British Thermal Unit (Btu)
1 kilowatthour(kWh)
("Fahrenheit (ฐF) - 32)
X
X
X
X
X
X
X
X
X
X
X
X
X
Factor
0.305
0.0929
3.78
0.0283
64.8
0.454
907
0.0703
6.895
1.05
3.60
0.556
                                    Metric
                                    meter (m)
                                    square meter (m2)
                                    liter (L)
                                    cubic meter (m3)
                                    milligram (mg)
                                    kilogram  (kg)
                                    kilogram  (kg)
                                    kilogram  per square
                                    centimeter (kg/cm2)
                                    kilopascal (kPa)
                                    kilojoule (kJ)
                                    megajoule  (MJ)
                                    'Celsius (ฐC)

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                                  ACKNOWLEDGEMENTS
     This report was prepared under the direction of Marta K. Richards,  EPA Superfund Innovative Technology
Evaluation (SITE) Project  Manager at the Risk Reduction  Engineering  Laboratory, Cincinnati,  Ohio.
Contributors and reviewers of this report included Donald A. Oberacker, Gregory J. Carroll, Jeffrey Worthington,
and Gordon E. Evans of U.S. EPA's Risk Reduction Engineering Laboratory and Jerrold S. Kassman, John
Winter, John Stevenson,  and Richard B. Zang of Texaco  Inc.

     This report was prepared for EPA's SITE Program by Foster Wheeler Enviresponse, Inc. (FWEI) in
Edison, New Jersey under EPA Contract No. 68-C9-0033. The FWEI SITE Project Manager for this project
was Seymour Rosenthal. FWEI contributors and reviewers for this report were James P. Stumbar,  Henry
Njuguna, and Marilyn Avery. Michelle Kuhn provided expert word processing  support.

     The authors would like to acknowledge the assistance provided by Robert  S. Burton III and the Montebello
Research Laboratory operations staff  in planning, preparing for, and supporting the SITE Demonstration and
the Radian Corporation staff for their  professional expertise in the collection and analysis of samples.
                                               XI

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                                  EXECUTIVE  SUMMARY

     This report summarizes the evaluation of the Texaco Gasification Process (TCP)  conducted under
the U.S. Environmental  Protection  Agency (EPA)  Superfund Innovative Technology Evaluation (SITE)
Program. The Texaco Gasification  Process was developed by  Texaco Inc.

     The TCP is  a  commercial gasification  process which converts organic  materials  into syngas, a
mixture of hydrogen  and carbon monoxide.  The feed reacts with a limited amount of oxygen (partial
oxidation) in a refractory-lined  reactor at temperatures between 2,200' and  2,650ฐF1  and at pressures
above  250 pounds per square  inch gauge  (psig). According to Texaco, these severe conditions destroy
hydrocarbons  and organics  in the  feed and avoid  the  formation of undesirable  organic by-products
associated  with  other fossil fuel conversion processes.   At  such  high  operating temperatures, the
residual ash  melts-forming an inert glass-like slag.

     Texaco reports that the syngas can be processed into high-purity hydrogen, ammonia, methanol,
and other chemicals, as well as clean fuel for electric power.

     The SITE Program evaluated the TCP's ability  to treat hazardous waste  materials containing both
organic compounds and inorganic heavy metal.  The primary technical  objectives of the Demonstration
were to determine the TCP's ability to:

     • Produce a usable  syngas product;
     • Achieve  99.99 percent Destruction  and Removal Efficiencies (DREs)  for organic compounds;
        and
     • Produce  a  non-hazardous primary  solid  residual-coarse   slag-and secondary  solid
        residuals-fine  slag and  clarifier  bottoms.
   'A list of conversion factors precedes the text.

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     Additionally, the Demonstration test results and  observations were  evaluated to:

     o  Develop overall capital and operating cost data; and
     •   Assess the reliability and efficiency of the TCP operations.

     The  TCP  was evaluated  under the  EPA SITE Program  in January 1994  at Texaco's Montebello
Research  Laboratory (MRL) in  South El Monte, California, located in the greater Los Angeles area. The
Demonstration used  a soil feed mixture  consisting  of approximately 20 weight-percent waste soil from
the Purity Oil Sales  Superfund  Site, Fresno,  California and 80 weight-percent  clean soil. The mixture
was gasified as  a slurry in water.  The slurry also included coal as a support fuel and was spiked with
lead and barium compounds (inorganic heavy metals) and chlorobenzene (volatile organic compound)
as the Principal  Organic Hazardous Constituent (POHC).  information on the TCP and results of the SITE
Demonstration at the Texaco MRL are provided herein.

     The  findings of the TCP SITE Demonstration  are as follows:

     • The TCP produced a syngas that can be used as feed for chemical synthesis  facilities or as a
       clean fuel for the production of electrical power when combusted in a gas turbine. The average
       composition of the  dry  synthesis gas product consisted of 37 percent hydrogen, 39 percent
       carbon  monoxide, and  21  percent  carbon dioxide.   No organic  contaminants, other than
       methane (55 ppml,  exceeded 0.1  ppm.   The  average heating  value of the gas,  a  readily
       combustible fuel, was  239  British thermal  units  (Btu) per dry standard  cubic foot  (dscf).
     • The ORE for the designated POHC (chlorobenzene) was greater than the 99.99 percent goal.
     • The average Toxicity Characteristic Leaching Procedure (TCLP) measurement for the coarse slag
       was lower than  the regulatory levels  for lead  (5 milligrams per liter)  (mg/L) and barium (100
       mg/L).    The  average California  Waste Extraction Test  (WET)-Soluble  Threshold  Limit
       Concentration (STLC)  measurement for the coarse' slag was lower than  regulatory value for
       barium  (100 mg/L)  and higher than the regulatory value  for lead  (5 mg/L).
     • Volatile heavy metals,  such as lead,  tend  to  partition and concentrate  in the secondary TCP
       solid products-fine  slag and clarifier solids. The average TCLP and WET-STLC measurements
       for these secondary TCP solid products were higher than  the regulatory limits for lead but lower
       than the regulatory limits  for barium.
     • Texaco estimates an overall treatment cost of $308 per ton of soil for a proposed transportable
       unit designed to process 100 tons per day (tpd)  of soil with characteristics similar to that from

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       the  Purity  Oil Sales  Superfund Site, based on a  value  of  $1.00/million Btu  for the syngas
       product. Texaco  estimates  an  overall treatment cost  of $225 per ton of soil for  a proposed
       stationary unit designed to process 200 tpd of soil, at  a central site, with  characteristics similar
       to that from the Purity Oil Sales Superfund  Site, based on a value of  $2.00/million  Btu for the
       syngas product.
     •   Based on  the  successful  operation of the TCP during the  SITE Demonstration  and  post-
       demonstration processing of the remaining slurry  inventory,  it is expected that  in  continuous
       operations,  proposed  commercial  units can  operate  at on-stream efficiencies  of 70  to  80
       percent allowing for scheduled maintenance and intermittent,  unscheduled shutdowns.

     The TCP technology evaluation  applied  the  EPA's  standard  nine criteria from the  Superfund
feasibility study (FS) process. Summary  conclusions  appear in Table ES-I.

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Table ES-1 . Evaluation Criteria for the Texaco Gasification Process Technology
Criteria
Overall
protection of
human health
and the
environment
Provides both
short- end long-
term protection
bit eliminating
exposuie to both
organic end in-
organic contam-
inants in soil.











Prevents further
groundwater
contamination
and off-site
migration by de-
stroying organic
contaminants
end demonstrat-
ing E potential to
immobilize heavy
metals into e
non-leaching
glassy, coarse
slag.


Compliance
with Federal
ARARs*
Requires compli-
ance with Re-
source Conserva-
tion and
Recovery Act
(RCRA) treat-
ment, storage,
and land disposal
regulations (of a
hazardous
waste).








Excavation end
construction and
operation of on-
site treatment
unit may require
compliance with
location-specific
ARARs.







Long-term
effectiveness
and
permanence
Effectively de-
stroys organic
contaminants and
demonstrates e
potential 1.0 im-
mobilize inorganic
heavy metals into
B non-leaching
glassy coarse
slag.









Site contaminants
are destroyed or
removed with
residuals.










Reduction of
toxicity.
mobility, or
volume through
treatment
Effectively de-
stroys toxic or-
ganic contami-
nants and demon-
strates B potential
to immobilize
inorganic heavy
metals into the
primary solid
product, a non-
leaching glassy
coarse slag.







Reduction of soil
10 glassy slag
reduces overall
volume of
material.












Short-term
effectiveness
Emissions and
noise controls are
required to elimi-
nate potential
short-term risks
to workers and
community from
noise exposuie
and exposuie IQ
contaminanTS and
particulate •
emissions
released to air
during
excavation.
handling, and
treatment prior \,Q
slurrying.



















Implementability
Treatability
testing required
for wastes
containing heavy
metals.














Large process
area required.
















Cost* •
Large-scale,
complex, high
temperature, high
pressure, trans-
portable thermal
destruction unit
at approximately
$308 per ton of
waste soil.










A larger.
stationary.
centrally-sited
plant with more
effective
integration with e
syngas product
user may reduce
the overall cost
to $225 per ton
of waste soil.






Community
acceptance
Large-scale, ex-
situ, high
temperature, high
pressure, thermal
destruction unit
may require
significant effort
to develop
community
acceptance.


























State
acceptance
If remediation is
conducted as
part of RCRA
corrective ac-
tions, state reg-
ulatory agencies
may require
operating per-
mits, such as: a
permit I.Q oper-
a\B the
treatment
system, an air
emissions
permit, and e
permit in store
contaminated
soil for greater
than 90 days.















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Table ES-1. (Continued)
Criteria
Overall
protection of
human health
and the
environment
Requires
measures to
protect workers
and community
during
excavation,
handling, and
treatment.


























Compliance
with Federal
ARARs*
Emission controls
are needed to
ensure
compliance with
air quality
standards, if
volatile
compounds and
particulate
emissions occur
during
excavation,
handling, and
treatment prior to
slurrying.
Wastewater dis-
charges to treat-
ment facilities or
surface water
bodies requires
compliance with
Clean Water Act
regulations.
CERCLA defines
drinking water
standards estab-
lished under the
Safe Drinking
Water Act that
apply to remedia-
tion of Superfund
sites.

Long-term
effectiveness
and
permanence
The potential
immobilization of
heavy metals into
non-leaching
glassy, coarse
slag requires
further testing for
anticipated long-
term stability.






Fine slag and
clarifier solids
may require
further treatment,
particularly when
volatile heavy
metals are
present.
Wastewaters
require further
treatment to
effect long-term
stability of
contaminants and
reuse of water.


Reduction of
toxicity,
mobility, or
volume through
treatment



































Short-term
effectiveness




































Implementability
Large-scale
transportable 100
tpd unit on
multiple trans-
portable skids
requires large
scale remediation
with on-site
commitment of
more than
50,000 tons of
soil and 2 years
of operation.


Initial transport-
able unit can be
constructed and
may be available
in 24 months.



Large size of unit
and ex-situ ther-
mal destruction
basis for unit may
provide delays in
approvals and
permits.






cost**
Simultaneous
treatment of
organic and in-
organic contami-
nants with credits
for resulting
syngas product
may overcome
initial cost
disadvantage.

























Community
acceptance



































State
acceptance

































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                                                                                   Table  ES-I.  (Continued)
Criteria
Overall
protection of
human health
and the
environment






















Compliance
with Federal
ARARs'
Requires compli-
ance with Toxic
Substances Con-
trol Act treatment
and disposal
regulations for
wastes
containing
polychlorinated
biphenyls.
CERCLA remedial
actions and
RCRA corrective
actions to be
performed in
accordance with
Occupational
Safety and Health
Administration
requirements.

Long-term
effectiveness
and
permanence




















Reduction of
toxicity,
mobility, or
volume through
treatment























Short-term
effectiveness
























Implementability
























cost**























Community
acceptance























state
acceptance




















O)
                        Applicable or relevant and appropriate requirements.
                        Actual cost of a remediation technology is highly site-specific and dependent  on matrix characteristics. See Economic Analysis- Section 3 of this
ITER.

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                                         SECTION  1
                                       INTRODUCTION

 1.1  BACKGROUND

     The Texaco Gasification Process (TCP) has been used to gasify conventional fuels, such as natural
gas, liquid petroleum  fractions, coal,  and petroleum coke for  more  than  45 years. More than 40
gasification plants are  either operational or under  development worldwide.

     According to Texaco,  wastes containing a broad  range  of  hydrocarbon  compounds have  been
gasified successfully. They  have demonstrated gasification of coal  liquefaction residues,  verifying the
nonhazardous content  of the  product  and treated effluent streams. In a program sponsored by the
California Department  of Health Services,  Texaco  reports the  successful gasification  of  California
hazardous waste material from an  oil  production field.  This program converted petroleum production
tank bottoms to synthesis gas and  nonhazardous effluent streams.  Texaco has also gasified mixtures
of municipal sewage sludge and coal. The data generated in these studies formed the basis  for permit
applications prepared by Texaco for commercial facilities in the United States. Texaco has  also gasified
surrogate contaminated soil  (clean  soil  mixed with unused motor oil), which was slurried with coal and
water.  According  to Texaco, the effluent streams  from gasifying this  feed were  nonhazardous.

     Waste  gasification  is an innovative  extension  of  Texaco's conventional  fuels  gasification
technology that reacts  carbonaceous materials with a limited  amount  of oxygen  (partial  oxidation) at
high temperatures. Hazardous waste gasification, using the TCP, offers an environmentally attractive
alternative to other thermal  and stabilization technologies. The TCP destroys any  hydrocarbons in the
feed and  effectively  recycles the waste  by transforming it into  clean  gas for use as fuel for power
generation or  an intermediate  product for  the  manufacture of transportation  fuels,  fertilizers, or
chemicals. The residual mineral  matter solidifies into small  pieces of glassy slag.  Texaco reports that
extensive  testing  has shown the aqueous effluent streams  to  be  free of priority pollutants and

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acceptable  for  discharge  after pretreatment  by conventional  wastewater technology.  None  of the
effluent  streams contained measurable concentrations of dioxins or  furans.

     Given its ability to deal with a variety of feedstocks, destroy organic compounds, produce a useful
synthesis gas,  and solidify  inorganic compounds  into potentially inert glassy slag, TCP offers  an
effective  treatment alternative  for  hazardous  wastes.

 1.2 BRIEF DESCRIPTION OF PROGRAM AND REPORTS

     The SITE  Program is a formal program established by  EPA's Office of Solid Waste and Emergency
Response (OSWER)  and Office of Research  and Development (ORD) in response  to the Superfund
Amendments and  Reauthorization  Act of 1986 (SARA). The SITE  Program's  primary purpose  is to
maximize the  use of alternative  remedies in cleaning  hazardous  waste sites by encouraging the
development and demonstration of new, innovative treatment and monitoring technologies. The  SITE
Program consists of four major elements discussed below.

     The Demonstration  Program  develops reliable  performance  and cost data  on  innovative
technologies so that potential users may assess the technology's  site-specific applicability. The
selected  technologies are either  currently  available  or  close  to  being  available  for  remediation of
Superfund sites. SITE Demonstrations are conducted on hazardous  waste sites under conditions that
closely  simulate  full-scale remediation  conditions, thus  assuring  the usefulness  and reliability of
information  collected. The data collected are  used  to assess the  performance  of  the technology, the
potential  need for pre- and post-treatment processing  of wastes, possible operating problems, and the
approximate costs. The  Demonstrations also  allow for evaluation  of long-term  risks, operating costs,
and maintenance.

     The Emerging  Technology  Program  focuses  on successfully  proven,  bench-scale  technologies
which are  in an early  stage of development involving  pilot  or laboratory testing.  It encourages
successful technologies  to advance to the Demonstration  Program.

     The Monitoring and  Measurement Technologies Program identifies  existing  technologies  which
improve field monitoring and site  characterizations. New technologies  that provide faster, more
effective  contamination and site assessment data are supported by this program. The Monitoring and

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Measurement Technology  Program also formulates the protocols and standard operating procedures for
demonstrating  methods  and equipment.

     The Technology Transfer Program disseminates technical  information  on innovative  technologies
in  the Demonstration, Emerging Technology, and  Monitoring and Measurements Technology  Programs
through  various activities.  These  activities  increase the awareness and promote the use of innovative
technologies for assessment and  remediation at  Superfund  sites.  The goal of  technology transfer
activities is to develop interactive communication among  individuals requiring up-to-date  technical
information.

     Technologies are selected  for the  SITE Demonstration  Program  through  annual  requests  for
proposals.  ORD staff review the  proposals to  determine which technologies  show the most promise
for use  at Superfund sites. Technologies must be  at the pilot- or full-scale  stage. Mobile  technologies
and  innovative  technologies that  incorporate  unique design features  and may offer advantages over
conventional existing  processes  for  the  remediation  of hazardous waste  matrices  are  of particular
interest.

     Once EPA has accepted a  proposal, a  cooperative agreement between EPA and the developer
establishes responsibilities for conducting the demonstrations and  evaluating the  technology. The
developer is responsible for demonstrating the technology at the selected site and  is expected to pay
any  costs  for  transport, operations,  and  removal of the  equipment.   EPA is responsible for project
planning, sampling and analysis,  quality assurance and quality control,  preparing reports, disseminating
information, and transporting and disposing of treated waste materials.

     The results  of  the  TCP demonstration are published in  two  (basic) documents: the SITE
Technology Capsule and  the Innovative Technology Evaluation Report (ITER). The SITE Technology
Capsule provides relevant summary information on  the  technology and key results  of  the  SITE
Demonstration. The  ITER  content is  defined in Section  1.3 and presented in  the succeeding sections.
It  provides detailed discussions  of the technology  and the results  of the  SITE Demonstration.  Both
publications are intended for use  by remedial managers evaluating the technology for a specific site and
waste.

     An additional document, the Technology  Evaluation Report (TER) contains all of the records and
data acquired during the predemonstration, demonstration,  and post-demonstration  phases of the test

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program.  It is available, on request, from the EPA SITE Project Manager listed in Section 1.5-Key
Contacts.

 1.3 PURPOSE OF THE INNOVATIVE TECHNOLOGY EVALUATION REPORT (ITER)

     The ITER provides definitive information on  the technology, SITE Demonstration and 'its results,
and conclusions and discussions about the applicability  and effectiveness of the technology  to
remediate hazardous waste sites based on the Demonstration results. The ITER is intended for use by
EPA remedial project managers, EPA on-scene coordinators, contractors, and other decisionmakers who
implement specific remedial actions. The ITER is designed to aid them in further evaluating the specific
technology as an applicable option in  a particular cleanup operation.

     This report represents a critical step in the development and commercialization of a treatment
technology.  To encourage the general use of demonstrated technologies, EPA provides information
regarding the applicability of each technology to specific sites and wastes. The ITER also includes
information  on cost and site-specific  characteristics.   It discusses advantages, disadvantages, and
limitations of the technology.

     Each SITE Demonstration evaluates the performance of a technology in treating a specific waste.
The characteristics of wastes at or from other sites may differ from the characteristics of the treated
waste.  Therefore, a successful field demonstration of a technology on a specific site waste or at a
specific site does not necessarily ensure that it will be applicable at other sites or to other waste
matrices.  Data from the field demonstration may require extrapolation for estimating the operating
ranges in which  the technology  will perform satisfactorily.

 1.4 TECHNOLOGY DESCRIPTION

 1.4.1  Process  Units

     Texaco maintains three pilot-scale  gasification  units with ancillary units and miscellaneous
equipment at the  Montebello  Research Laboratory  (MRL), where  the SITE  Demonstration  was
conducted. Each  gasification unit at MRL can handle  a nominal throughput of 25 tpd of coal. The High
Pressure Solids Gasification Units I and II (HPSGU I and II) and the Low Pressure Solid Gasification Unit
(LPSGU) are rated for operation at pressures up to 1,200  psig and 400 psig,  respectively. HPSGU I and

                                             10

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II use a direct quench, mode for cooling the gas, while the LPSGU adds the  option of cooling the gas
by indirect heat exchange with  water.  Only one of the three units operates  at a  given time.

     This SITE Demonstration  evaluated  the  operation of the  HPSGU II  in conjunction  with other
systems for the storage and grinding of solid fuels, generation and storage of slurries, acid gas removal,
sulfur removal, and  on-site wastewater treatment.  Figure 1-1 is a block flow diagram, which  identifies
the major subsystems.

1.4.2   Solids Grinding  and Slurry  Preparation Unit

     The feed was prepared in  the  Solids Grinding and Slurry Preparation Unit in a two-step  process:

     •   Dry solids were  crushed in a hammer mill.
     •   The crushed solids were ground  and mixed with the  waste and water in  a wet rod mill.

     Figure 1-2 is the process flow diagram for the Solids  Grinding and Slurry Preparation Unit.

1.4.2.1  Crushing-

     Coal arrived at the  plant  in  bottom-dumping  'trucks  that  loaded it directly into  a  truck dump
hopper, or piled it on-site for storage. (Skip loaders transferred stored coal to the truck dump hopper.)
From the truck dump hopper, the coal traveled on a feed belt  to a bucket elevator, which  delivered it
either to the coal silo or to the  smaller, bypass  hopper,  From either device, the  coal dropped onto a
conveyor belt, passed through a  magnetic  separator and a metal detector, and entered the hammer mill.
A conveyor belt scale controlled the coal  feed rate to the hammer mill. The  hammer mill  crushed the
coal to  a size  appropriate for feeding to the wet rod mill. The crushed coal  was  conveyed to the mill
feed hopper.

1.4.2.2  Waste Feed-

     The contaminated soil was dumped  from drums into the waste feed hopper and metered into the
wet  rod mill using a bin  feeder and bucket elevator system. The soil addition started after  the wet rod
mill had been started; it was completed  before the wet rod mill shutdown to ensure that all the soil was
                                                11

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                                                                MAKE-UP
                                                                 WATER
           COAL
INORGANIC
  SPIKE
             AND SLURRY
            PREPARATION
               TO
            DISPOSAL
                                                                  GAS
                          COAL/WASTE
                         HIGH
                            SOLIDS
                                   UNIT
ACID BASf
 SULFUR
REMOVAL
                                QRGAMC
                                 SPIKE
                            COARSE SLAG
                            CLARIFIER SOLIDS
                                                    WASTEWATER
                                                     TREATMENT
                                                  NEUTRALIZED
                                                                    WASTEWATER

                                                               EFFLUENT WATER
                                                                 CAUSTIC/
                                                                  ACID
                                                                     FUEL GAS



Figure l-l. Block Flow Diagram of MRL TCP During SITE Demonstration.

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Figure 1-2.  Solids Grinding and Slurry Preparation Unit Process Flow Diagram.

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transferred to the slurry storage tanks.  The  slurry  in the tanks was analyzed to determine the solids
concentration  in the slurry.

1.4.2.3  Slurrying-

      For the preparation of the Purity Oil soil slurry,  the mill feed hopper dropped the coal onto a weigh
belt that metered  its flow into the wet rod  mill where it was simultaneously ground and  slurried with
water. A belt  scale controlled the speed of the weigh belt to achieve the desired feed rate. The  mill
feed water line mixed water with the coal and the contaminated soil at the entrance to the wet rod mill.
The  mill discharged the slurry, which  passed  through a screen,  into the  slurry  surge tank.  Pumps
moved it to the gasification slurry storage  tanks.  During grinding, frequent grab samples  of the slurry
provided a means of determining the solids  concentration.  An operator then  adjusted the mill water
feed rate as required.  A small quantity of oversized material,  screened from the slurry, was collected
in a  bin  for proper disposal or recycled through the solids grinding system.

      For the extended SITE Demonstration, additional slurry was required and prepared using clean soil
since further supplies of Purity Oil soil were not readily available. For the preparation of the clean soil
slurry, coal and clean  soil  were weighed, using a front-end loader and  a truck scale. The truck dump
hopper was filled  with  alternating loads of coal and soil at the  predetermined ratio. Any lime required
to control slag viscosity was preweighed and added to the hopper with the soil.

      SAE 30 oil from  preweighed drums was added at the wet rod mill  inlet using a pneumatic pump.
The  oil was added to  match the heating value of the Purity Oil soil in the Purity Oil soil slurry and to
provide  a  similar level of hydrocarbon contamination  in the clean soil  slurry.  Had  any  operating
problems with the oil transfer pump occurred, the oil in the drums could have been added directly to
the slurry in  the slurry  storage tank.

1.4.2.4  Additives-

      Gypsum, a dry additive (ash viscosity  modifier), entered the process through a dry  additive hopper
in the same  manner as the contaminated  soil. A  surfactant liquid additive  (slurry viscosity modifier),
entered the feed in the wet rod mill via the mill feed water line.
                                                 14

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1.4.2.5 Particulate and Odor Emissions Control-

     The Solids Grinding and Slurry Preparation Unit included a baghouse and dust control system to
control particulate emissions. Enclosed coal conveyor belts and coal handling equipment upstream of
the weigh  belts operated under a slight  negative  pressure. The baghouse collected particulates and
recycled them to the process downstream of the hammer mill. The gas discharge from the baghouse
passed through a  carbon canister for organics removal. In addition, a nitrogen blanket on the coal silo
prevented the creation of an explosive atmosphere.   The wet rod mill and slurry storage tank were
enclosed and the  vent line from them was also routed to a carbon canister for organics removal.

1.4.3  High Pressure Solids Gasification Unit

     The HPSGU  II can handle a nominal throughput of 25 tpd of coal. The gasifier was designed to
operate at pressures up to 1,200 psig and internal temperatures  up to 2,SOOT. This  unit is a direct
quench gasifier where the hot syngas and molten slag are cooled by direct contact with water. Figure
1-3 shows the process flow diagram for the HPSGU II.

1.4.3.1 Slurry Feed System-.

     For the preparation of the SITE Demonstration slurry, the clean soil slurry was blended with a
portion of the Purity Oil soil slurry to produce the mixed test slurry for the SITE Demonstration runs.
The blending was  accomplished by filling a slurry storage tank to the appropriate level with one of the
slurries and then adding the required amount of the other slurry to achieve the desired level in the tank.
The quantity of each  slurry was measured by slurry storage tank level.

     The mixed test slurry was pumped to the two gasification slurry storage tanks and the single
slurry run tank located adjacent to the HPSGU II. The tank group held sufficient capacity for a 3 to 4-
day gasification test. Slurry from any of the MRL storage tanks could be fed to the gasifier run tank.

     The slurry storage and run tanks, equipped with paddle mixers and slurry circulation/transfer
pumps, kept the slurry in constant motion and maintained homogeneity. Agitation was enhanced by
sparging the tanks with nitrogen. All of the tanks were equipped with vibrating screens to separate
oversized material from the slurry.
                                              15

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                                                                                                                    f  RtW
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                                                                                                                      H;
                                                                                                                              	_ to SIWA6E
Figure 1-3.  High Pressure Solids Gasification Unit II Process Flow Diagram.

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     Conventional charge pumps fed the slurry from the slurry run tank to the gasifier. The slurry flow
rate was varied by adjusting the charge pump speed; it was monitored by several flow meters. The
slurry run  tank was mounted on a scale, allowing an additional check (by weight) on the slurry charge
rate.

     For the TGP SITE Demonstration, a metering pump injected the chlorobenzene organic liquid spike
into the slurry flow at the gasifier inlet. The barium nitrate and lead nitrate inorganic metal salts had
been weighed and directly added to the slurry in each of the slurry storage tanks.

     High purity oxygen supplied the oxidant feed to the gasifier. Stored on site as a liquid, the oxygen
was vaporized and  heated  under high pressure before being charged to the gasifier. The oxygen flow
to the gasifier was  measured and controlled.

1.4.3.2 Gasification-

     The  HPSGU II is a two-compartment vessel, consisting of an upper refractory-lined, reaction
chamber and a  lower quench chamber.  Oxygen and slurry feeds were charged through an injector
nozzle  into the  reaction chamber where they reacted under highly reducing conditions to produce raw
syngas and molten  ash.   The following  chemical  conversion formula describes the continuous,
entrained-flow, pressurized, non-catalytic,  partial-oxidation  TGP process, in which  the carbonaceous
materials react with  oxygen or air:

                             CnHm +  n/2  02	 >   nCO + m/2 H2

     The  gasifier temperature was measured and controlled to maintain an operating temperature
sufficient to convert the  soil and  coal ash into molten slag by  adjusting the oxygen-to-slurry feed rate
ratio. The  raw syngas consisted primarily of carbon monoxide  and  hydrogen, with lesser quantities of
carbon dioxide  and traces of methane. Chlorinated species in the feed became hydrogen chloride in
the raw syngas. Any  sulfur in the feed was  converted into hydrogen sulfide and carbonyl sulfide, and
any unreacted fuel was converted to char.  The average pressure was 500 psig. The pressure was
controlled by a  control valve downstream of the gas coolers.

     From the  reaction chamber, the raw syngas and molten ash  flowed into the quench chamber,
where  the water cooled  and  partially scrubbed the raw  syngas.  It  also converted the molten ash into
                                              17

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small pieces of glassy slag, which then passed down into the lockhopper. The quench water was then
cooled and directed to the clarifier to  remove solids.

1.4.3.3 Gas Scrubbing and  Cooling—

     The raw syngas  leaving the quench chamber contacted additional water in the raw gas scrubber,
which further reduced  the hydrogen chloride and particulate content in the syngas. The scrubber water
combined  with  the quench water and was cooled before  flowing to the  clarifier.  The scrubbed  raw
syngas was further cooled in a heat exchanger separating  the entrained liquid water condensate from
the gas in the  high pressure  knockout  pot.  The pressure  of the scrubbed raw syngas  was lowered and
any additional  entrained water separated from the  gas  in the low pressure knockout pot was routed to
the HPSGU II  sump.  After  the gas  exited this second knockout  pot, the  flow was measured and
samples were  taken. The gas was then fed to the Acid  Gas Removal Unit for  cleanup before flaring.

1.4.3.4 Solids  Recovery and Water Handling-

     Due  to the nature of the solids  residuals/gas quenching and scrubbing  methods,  two separate
solids/water handling  systems were  necessary.  The  lockhopper system handled the coarse  and fine
slag solids.  The  quench/scrubber system  both  cooled and scrubbed the  raw  syngas, and then
recovered  entrained particulate.

     Lockhopper Svstem-The lockhopper  system  used a cyclic  mode of operation to remove coarse
and fine slag solids from the gasification  unit.  During the collection cycle,  the lockhopper was open
to the gasifier at gasifier pressure.  The slag from the quench chamber fell through the top valve and
accumulated in the lockhopper.

     In the discharge  cycle,  the top lockhopper valve closed, and the lockhopper was depressured to
atmospheric pressure.  The  bottom lockhopper and lockhopper  flush tank discharge valves  opened,
allowing water from the flush tank to move  the contents of the lockhopper into the slag receiver below.
As the flush tank level fell, the bottom lockhopper valve closed,  keeping the lockhopper full of water.
The  lockhopper returned  to  gasifier pressure using a dedicated pressurizing  pump  system.  The top
lockhopper valve then  opened, resuming the  collection cycle.
                                               18

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     The slag and water from the lockhopper blowdown were delivered from the slag receiver to the
shaker screen by a rotary valve. The shaker screen separates the slag into coarse slag  and fine slag
fractions.  The coarse slag fell  off the  screen into a  bin hopper.  When  the bin hopper was full  an
operator  replaced it and weighed/sampled the coarse  slag.

     The fine slag  passed with the flush water down through the shaker screen into the slag fines
settler. The fine  slag was  drawn from the bottom of the settler and pumped to the vacuum belt filter.
The resulting fine slag cake fell into a separate bin hopper.  When this bin hopper was full an operator
replaced  it and weighed/sampled  the fine slag.

     The filtrate from the vacuum belt filter returned to the weir of the slag fines settler where it mixed
with the overflow of the slag fines settler. This liquid, pumped through a cooler back to the lockhopper
flush tank, recycled in the  next lockhopper cycle.

     Quench/Scrubber Svstem-The system continually  routed the water  in the quench  chamber and
scrubber vessel  to the clarifier  via coolers. The  clarifier produces an underflow stream of solids and
water,  called  clarifier bottoms,  and an  overflow  stream of clarified water, known  as the clarifier
overhead.

     Periodically the clarifier bottoms  were drawn  off and  filtered to produce  a filter cake (clarifier
solids-approximately  45  wt%  solids), and a filtrate  stream  (vacuum  filtrate).  Operators  sampled  the
clarifier bottoms both before  and after filtering.  The  bottoms were also weighed after filtering.

     The clarifier overhead flowed into the flash tank  where it mixed  with the blowdown stream from
the high  pressure knockout pot. In the  flash tank dissolved gases were removed from these waters at
low pressure. The water then  recycled back to the quench chamber and scrubber vessel or was routed
to temporary  storage or wastewater treatment as a blowdown stream. The flash gas was cooled and
routed  to  the flash gas knockout pot before going to the Sulfur  Removal Unit for removal of sulfides.
Any water that accumulated in  this knockout  pot was routed to the  HPSGU II sump. When required,
water was added to  the quench/scrubber system at the  flash tank. Makeup water was drawn from an
on-site well and  softened.
                                               19

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1.4.4  Acid Gas Removal Unit

     The  Acid Gas Removal Unit, shown in Figure I-4, removed hydrogen sulfide, carbon dioxide, and
small  amounts  of  hydrogen  chloride and chlorine  (acid  gases) from the scrubbed raw syngas. The
solvent used  in this absorption operation was  Selexols,  a polyethylene glycol dimethyl  ether solution
supplied by Sherex Chemical Company under license from Union Carbide.

     Scrubbed  raw syngas  from the  gasification unit flowed to the  raw  syngas  knockout  pot  for
removal of small amounts of entrained process water, which were routed to  the sump.  The scrubbed
raw syngas then entered the bottom of the Selexols absorber tower and rose up the tower against a
counter-current  flow of stripped solvent called  lean Selexole  or lean solvent. The Selexole absorber
tower operated  at conditions  that removed approximately  80-95 percent of the hydrogen sulfide as well
as the remaining hydrogen chloride  and chlorine in the raw syngas

     This treated raw syngas, called fuel gas, flowed from the top  of the Selexole  absorber into  an
absorber  knockout pot where  small amounts  .of.  entrained solvent  were removed and routed  to  the
sump. The dry  fuel gas was then sampled, metered, and  flared.

     A solvent stream,  called  rich  Selexolฎ or rich solvent because it is concentrated  with acid gas
consisting mainly of hydrogen sulfide  and  carbon dioxide, flowed  from  the bottom of the  Selexole
absorber to the solvent-solvent exchanger where  it was  heated by hot lean  solvent.  The rich solvent
was further heated in  a steam heat exchanger before entering the top of the Selexolฎ  stripper.  The
rich solvent flowed down the tower, contacting steam, which  stripped out the  acid  gases.

     The  acid gases and steam flowed from the  top of  the tower 'through a cooler to the reflux pot.
Water condensed out in this pot and was pumped back to  the  rich solvent line upstream of the solvent-
solvent exchanger. The  overhead acid  gas  stream from  the reflux pot,  consisting  mainly of hydrogen
sulfide and carbon dioxide and known  as sour gas, flowed to the Sulfur Removal  Unit.

     Lean solvent  exited the bottom of the stripper. There, a portion  was drawn off, heated in external
reboilers,  and fed to the separator, where lean solvent separated from the steam.  The steam was  fed
to the middle section of the stripper, while the  lean solvent from the  separator was combined with  the
balance of the lean solvent from the bottom  of the  stripper. The composite lean stream was cooled first
                                              20

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                                                                                run GAS ion?)
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Figure 1-4.  Acid Gas Removal  Unit Process Flow Diagram.

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in the solvent-solvent exchanger, then sent through a cooler and directed  into the  Selexol surge pot
where a level of lean solvent is maintained to ensure a constant flow to the absorber. A pump moved
the  composite lean solvent from the Selexol surge pot, through additional coolers to the top of the
absorber tower.

1.4.5 Sulfur  Removal Unit

     The  Sulfur Removal Unit, shown in  Figure  1-5, separated hydrogen  sulfide from the sour gas
stream from the Acid Gas Removal Unit  and the flash gas stream from  the gasification section.  It
converted  hydrogen sulfide to a sodium thiosulfate solution,  which was treated in the MRL Wastewater
Treatment Unit  (WWTU).

     The  combined  flow of sour gas from the Acid Gas  Removal Unit and the  flash gas from  the
HPSGU II entered the bottom of the caustic absorber.  In  the absorber,  the composite gas stream
contacted  a counter-current  aqueous solution of  sodium hydroxide (caustic), which  reacted with  the
gaseous  hydrogen sulfide to produce  sodium sulfide.   Carbon dioxide in  the sour  gas  stream also
reacted  with the caustic to  produce sodium  bicarbonate.   The caustic absorber achieved 85  to 95
percent removal  of the hydrogen sulfide in the sour gas. The residual gas,  known  as caustic absorber
off-gas, traveled  to an absorber knockout pot  before flaring  as  absorber off-gas. Any entrained caustic
was routed to the  unit sump.

     Pumps sent the spent caustic  from the bottom of the caustic  absorber through a meter to the
oxidizer tower.  A  portion  of the  spent caustic stream  recycled to  the top  of the  caustic  absorber
through a  meter in the spent caustic recycle line.  Mixed with fresh  caustic,  it cooled in an  exchanger,
and then (mixed with water) reentered the absorber.

     A heated storage tank,  aboveground in a bermed area, stored  fresh caustic as a 50 weight-percent
aqueous  solution of  sodium hydroxide.

     At the oxidizer tower, the spent caustic stream was mixed with compressed air  and steam,  and
fed  to the bottom  of the oxidizer tower. The  caustic, air, and  steam reacted with  the sodium sulfide
to  produce sodium thiosulfate.
                                              22

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NJ
CO
            FROM	
            ACID GAS
            pfMOVAL
            LW
                            FROM
                         GASIFICATION!
                            UNIT
                                        t
                                              SMUT CAUSTIC
                                                                        CAUSTIC ABSORBS?
                                                                         OfF-GAS
                                                                                FRESH CAUSTIC „
                                                                                SPENT CAUSTIC
                                                                                                AIR. STEAM
                                                                                                                                                          OXIOIZER
                                                                                                                                                          OFF CAS
        Figure  1-5. Sulfur  Removal  Unit  Process  Flow  Diagram.

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     The oxidizer tower operated in an overflow mode. The vapor and liquid phases flowed out of the
top of the tower and passed through a cooler before entering the oxidizer knockout pot. The overhead
gas from the oxidizer knockout pot, called oxidizer off-gas, flowed to the off-gas  knockout pot before
being flared. Any residual entrained solution was routed to the unit sump.

     The liquid phase separated in the oxidizer knockout pot was an aqueous mixture of sodium
thiosulfate and sodium hydroxide.  In a neutralization line, the pH was adjusted to approximately 7 by
the automated addition of sulfuric  acid. The neutralized stream then discharged to the WWTU.

     An aboveground tank located in an adjacent  bermed area stored sulfuric acid  as 93 weight-percent
aqueous solution. The pH of the wastewater stream was continuously monitored downstream of the
mixing point by an instrument which directly controlled the amount of acid being pumped into the line.

1.4.6   Other Ancillary Units and Miscellaneous  Equipment

1.4.6.1  Flare-

     MRL employs a flare system to combust the fuel gas from the Acid Gas Removal Unit and  the off-
gases from the Sulfur Removal Unit.  Hydrogen and carbon  monoxide  were the  primary  combustible
components in  the off-gases. The oxidizing environment at the flare provided a fuel-lean stoichiometry
and complete combustion of the raw syngas,  producing primarily carbon dioxide and water. Continuous
monitoring of the flare flame temperature verified proper operation. If the flame had been extinguished,
the flare would automatically have  attempted to reignite and sound an alarm.

1.4.6.2  Wastewater Treatment  Unit--

     MRL maintains an on-site Wastewater Treatment Unit (WWTU)  for processing plant wastewater
before  discharging it to a municipal sewer.

     The WWTU treats wastewater from the following sources

     •  Sulfur Removal Unit neutralization  line
     •  Stormwater drains  in process areas
     •  Laboratory sinks
                                              24

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     .  Solids Grinding  and Slurry Preparation Unit sump
     . Ancillary process unit sumps
     .  Boilers
     •  Water  softeners

     The WWTU  employs  neutralization,  flocculation,  clarification,  and filtration  to  meet the effluent
discharge specifications  required by the Los  Angeles County  Sanitation Districts.

1.4.7 Waste  Disposal

     Solid wastes  and wastewaters  generated during  the operation  and decontamination of process
equipment were tested for  hazardous characteristics.  Hazardous wastes were transported  off-site for
proper disposal. These  wastes included:

     .  Slag  and  clarifier solids
     •  Process wastewater streams
     •  Washdown  water
     o  Unused feed  and other test-defined  feed  materials (hazardous waste, hazardous slurries, and
         miscellaneous spiking chemicals  and additives)
     . Rinse  water generated  during decontamination
     • Used disposable personal protection  and decontamination materials.

1.4.7.1  Solids-

     Slag  and  clarifier  solids,  generated  from the gasification  process, consisted primarily of the
inorganic/mineral matter present in the coal and hazardous waste feed. These solids were  stored in
lined, certified, steel roll-off bins leased from  a  licensed hazardous waste transporter. Each  roll-off bin
was covered with a water-proof canvas tarpaulin. Samples of each stream sent to the roll-off bins were
retained  and analyzed; waste logs were maintained on  all  roll-off bin  contents. The  waste solids were
transported via a licensed hauler to  a permitted treatment, storage, and disposal facility  in compliance
with all federal and state regulations.
                                                25

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1.4.7.2  Process Wastewater and  Washdown Water—

     During gasification tests, two process wastewater streams, the flash  tank blowdown  and the
clarifier  underflow vacuum filtrate, are discharged  from the HPSGU II to the  WWTU.  At the end  of a
gasification run, the  quench/scrubber system and the lockhopper system  water inventories are  also
normally discharged to the WWTU. Because this SITE Demonstration  used California hazardous waste
as gasifier feed material,  these  four water streams  diverted  to  temporary storage, sampled, and, if
hazardous  properly disposed of off-site.

     A  fifth process  wastewater stream was generated by the Sulfur  Removal  Unit during gasification
operations. This stream contained  sodium sulfate  and sodium thiosulfate.  This stream did not exhibit
hazardous  characteristics  as a result of gasifying a hazardous  waste and  was diverted to  storage,
followed by off-site treatment and  disposal.

     Water generated from washing  down the process plot area  is normally discharged to the WWTU
via a sump system. Because a hazardous waste was used as a  gasification feedstock, this water was
not allowed to  flow to the WWTU. Instead, it was stored and removed by vacuum truck for off-site
treatment  and disposal.

1.4.7.3  Unused Hazardous Waste  Feed, Hazardous Waste Feed/Coal Slurry  and Coal-

     All unused feed materials were gastfied after the SITE Demonstration tests were completed. The
hazardous  waste residuals were transferred to  an off-site  hazardous  waste disposal facility. The coal
that was not consumed was stored on-site for  future use.

1.4.7.4  Decontamination Rinse  Water-

     Decontamination rinse water generated during gasification operation was discharged to the sumps
that serve  the  unit being  decontaminated.  This water was isolated from the WWTU  and transported
by a certified waste  transporter via vacuum truck to a permitted off-site treatment facility.
                                              26

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1.4.7.5 Contaminated  Oil-


     Oils for machinery lubrication were stocked in barrel racks located inside the tank retaining wall.

When in  use,  these  barrels  were fixed in such a position that  normal spills drained into an oil/water

sump for  pumping into a waste  oil tank.  Waste oil removed from machinery  was stdred in 55-gallon

drums  prior to transport to a permitted disposal facility. Small oil spills elsewhere  in the MRL facility

were treated with an oil absorbing material,  which was sent for disposal  as hazardous waste.


1.4.7.6 Used Health,  Safety, and  Decontamination  Material(s)-


     Used  personal protection materials (Tyvek suits, gloves, towel wipes,  etc.) were  collected in a

dumpster  and  transported  as hazardous waste by a  certified  service to a permitted off-site treatment

facility.


 1.5 KEY CONTACTS


     Additional information on the SITE Program, the TCP  SITE Demonstration,  and TCP technology

are available from the following sources:


     The  SITE Program

     Robert A. Olexsey                                    Marta  K. Richards
     Director, Superfund  Technology Demonstration  Division EPA SITE  Project Manager
     U.S.  Environmental Protection Agency                 U.S.  Environmental  Protection  Agency
     26  West Martin Luther King Drive                      26  West Martin Luther King  Drive
     Cincinnati,  OH  45268                                Cincinnati,  OH 45268
     513-569-7861                                        513-569-7692
     Fax  513-569-7620                                   Fax 513-569-7549

     The Texaco Gasification Process Technology

     Richard 6. Zang
     Texaco Inc.
     2000  Westchester Avenue
     White Plains, NY 10650
     914-253-4047
     Fax  914-253-7744
                                               27

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     On-Line Clearinghouses

     •  The Alternative Treatment Technology Information Center (ATTIC) System (operator 301-670-
       6294)  is a  comprehensive,  automated information  retrieval  system that integrates data on
       hazardous waste  treatment technologies into  a  centralized,  searchable  source. This database
       provides summarized  information  on  innovative treatment technologies.

     o  The  Vendor Information System  for Innovative Treatment Technologies  (VISITT)  (Hotline: 800.
       245-4505)  database contains  information  on 154 technologies  offered  by 97  developers.

     •  The  OSWER CLU-ln electronic  bulletin  board contains information on the  status of SITE
       technology  demonstrations. The system operator can  be reached  at  301-585-8368.

     Publications

     Technical reports  may be  obtained  by  contacting the  Center for  Environmental  Research
Information (CERI),  26 West Martin  Luther  King  Drive, Cincinnati,  OH  45268 at 513-569-7562.
                                              28

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                                       SECTION 2
                       TECHNOLOGY APPLICATIONS ANALYSIS

     This section of the report addresses the general applicability of the Texaco Gasification Process
(TGP) for the treatment of hazardous wastes contaminated  with  organics  and heavy metals. The
conclusions are based primarily on the TGP SITE Demonstration results supplemented by information
on other applications of the technology, presented in Appendix II.

2.1 OBJECTIVES - PERFORMANCE VERSUS ARARs

     Specific environmental regulations pertain to the operation of the TGP, including the transport,
treatment, storage, and disposal of wastes and treatment residuals. These regulations may affect the
future development of commercial TGP units.

     For the TGP SITE Demonstration, the primary waste feed materials were transported from the
Purity Oil Sales Superfund Site in Fresno, California to the TGP's location at Texaco's  MRL in South El
Monte, California. Such waste treatment, if conducted on a hazardous waste, would be considered
off-site treatment. All  substantive and administrative regulatory  requirements for waste transport,
storage, treatment, and disposal at the federal, state, and local level must be fulfilled.

     The operation of MRL is regulated by environmental permits covering air quality, water quality,
and the storage and treatment of hazardous wastes.  Air quality permits have been issued by the
regional South Coast Air Quality Management  District (SCAQMD),  with individual permits covering all
pertinent operations facilities at the MRL. The MRL does  not have a National Pollutant Discharge
Elimination System (NPDES) permit for direct wastewater discharge.  Instead, wastewater is pretreated
by an on-site wastewater treatment plant and then discharged to  a municipal sewer. This discharge
is permitted by the Los Angeles County Sanitation Districts and is routed to  their treatment facilities.
The MRL is classified  as a  hazardous waste generator. Hazardous waste residuals are sent to certified
treatment,  storage, and disposal facilities in compliance with U.S. EPA and California EPA regulations.
                                            29

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Permits held by MRL allow routine research and development as well as support activities. New
research programs require the modification of existing permits and the addition of new permits.
Depending on the length  of the research programs, these modifications and new permits can be
temporary. Such permits terminate at the end of the short-term research.

     For this specific SITE Demonstration, the waste soil excavated from the Purity Oil Sales Superfund
Site was  prescreened, pH modified, analyzed, and predetermined not to be a Resource, Conservation,
and Recovery Act (RCRA)  hazardous waste. It was then sealed in drums and transported to Texaco's
MRL. Based on these conditions, the State of California Environmental Protection Agency (CAL-EPA)
Department of Toxic Substances Control  issued a variance to MRL from  the hazardous waste facility
permit under generator and transporter regulatory requirements of Division 4.5, Title 22, California Code
of Regulations (CCR).   The waste soil was still considered a California  hazardous waste and all
operations were properly conducted  under these regulations.

     When a proposed transportable TGP system is constructed for on-site treatment at Superfund
sites, the substantive requirements discussed in this Section would be considered applicable or relevant
and appropriate requirements (ARARs). However, the administrative requirements (obtaining the actual
permits), would not have to be fulfilled.

     Potential TGP technology  users should understand and satisfy the requirements of all applicable
local, state, and federal  regulations.  Specific ARARs  include the following: (1) the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA);  (2) the Resource Conservation and
Recovery Act (RCRA); (3) the Clean Air Act (CAA);  (4) the Safe  Drinking Water Act (SDWA); (5) the
Clean Water Act (CWA); (6) the  Toxic Substances Control Act (TSCA); and (7) the Occupational  Safety
and Health Administration (OSHA) regulations.  In addition to these seven general ARARs, discussed
below, specific ARARs must be  identified by remedial managers for each site. Specific federal and state
ARARs which may be applicable to the TGP technology are addressed in Table 2-I.

2.1.1   Comprehensive Environmental Response, Compensation, and Liability Act

     The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980
as amended  by the Superfund Amendments and Reauthorization Act (SARA) of 1986  provides for
federal funding to respond to releases of hazardous substances to air, water, and land. Section 121
of SARA, entitled "Cleanup Standards",  states  a strong statutory preference for remedies that are
                                             30

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Table 2-1. Federal and  State ARARs for the Texaco  Gasification  Process  Technoloav
Process
activity
Waste feed characterization
(untreated waste)
Soil excavation
Storage prior to processing
Transportation for on-site
processing and off-site
disposal
ARAR
RCRA 40 CFR Part 261 or
state equivalent
TSCA 40 CFR Part 761 or
state equivalent
Clean Air Act 40 CFR 50.6,
and 40 CFR 52 Subpart K or
state equivalent
RCRA 40 CFR Section 262 or
state equivalent
RCRA 40 CFR Section 264 or
state equivalent
RCRA 40 CFR Part 262 or
state equivalent
RCRA 40 CFR Part 263 or
state equivalent
Description
Identify and characterize the
waste as treated.
Apply standards to the
treatment and disposal of
wastes containing PCBs.
Manage toxic pollutants and
participate matter in the air.
Apply standards to
generators of hazardous
waste.
Apply standards to the
storage of hazardous waste
Mandate manifest require-
ments, packaging, and label-
ing prior to transporting.
Set transportation standards.
Basis
A RCRA requirement must be
met prior to managing and
handling the waste.
During waste
characterization, PCBs may
be identified in contaminated
soils, and soils would then be
subject to TSCA regulations.
Fugitive air emissions may
occur during excavation,
material handling, and
transport.
The soils are excavated for
treatment.
Excavation may generate a
hazardous waste that must
be stored in a waste pile.
The waste soil or solids
products may need to be
manifested and managed as a
hazardous waste.
Waste soil or solids products
may need permitted
transportation as a hazardous
waste.
Response
Chemical and physical
analyses must be performed.
Chemical and physical
analyses must be performed.
If PCBs are identified, soils
will be managed according
to TSCA regulations.
If necessary, the waste
material should be watered
down or covered to eliminate
or minimize dust generation.
If possible, soil should be fed
directly into the unit for
slurrying.
In a waste pile, the material
should be placed on and
covered with plastic tied
down to minimize fugitive air
emissions and volatilization.
The time between
excavation and treatment
should be minimized.
An identification (ID) number
must be obtained from EPA.
A transporter licensed by
EPA must be used to
transport the hazardous
waste.

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                                               Table 2-1. (Continued)
Process
activity
Waste processing
Storage after processing
Waste product
characterization (treated
waste)
ARAR
RCRA 40 CFR Parts 264 and
265 or state equivalent
Clean Air Act 40 CFR 50.6,
and 40 CFR 52 Subpart K or
state equivalent
RCRA 40 CFR Part 264 or
state equivalent
RCRA 40 CFR Part 261 or
state equivalent
TSCA 40 CFR Part 761 or
state equivalent
Description
Apply standards to the
treatment of hazardous waste
at permitted and interim
status facilities.
Manage toxic pollutants and
participate matter in the air.
Apply standards to the
storage of hazardous waste
in containers.
Apply standards to waste
characteristics.
Apply standards to the
treatment and disposal of
wastes containing PCBs.
Basis
Treatment of hazardous
waste must be conducted in
a manner that meets the
RCRA operating and
monitoring requirements.
Fugitive air emissions may
occur during solids grinding
and slurry preparation.
The treated solid products
will be placed in covered roll
offs or equivalent containers
prior to a decision on final
disposition.
A requirement of RCRA prior
to managing and handling the
waste; it must be determined
if the solids products is RCRA
hazardous waste.
Treated solids products may
still contain PCBs.
Response
Equipment must be operated
and maintained daily. Air
emissions must be
characterized by continuous
emissions monitoring.
Equipment must be
decontaminated when
processing is complete.
Unit design includes
negative pressure within
enclosures, nitrogen
blanketing, baghouse
collection, and carbon
adsorption of vapors.
The treated solids products
must be stored in containers
that are well maintained;
container storage area must
be constructed to control
rain-water runoff.
Chemical and physical tests
must be performed on
treated solids products prior
to disposal.
Chemic al and physical tests
must be performed on
treated solids products. If
PCBs are identified, a proper
disposal method must be
selected.
GO
Ni

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                                                 Table  2-1. (Continued)
Process
activity
Wastewater discharge
On-site/off-site disposal
ARAR
Clean Water Act 40 CFR
Parts 301, 304, 306, 307.
306. 402, and 403
Safe Drinking Water Act 40
CFR Parts 141 and 143
RCRA 40 CFR Part 264 or
state equivalent
TSCA 40 Part 761 or state
equivalent
RCRA 40 CFR Part 268 or
state equivalent
Description
Apply standards to discharge
of wastewater into sewage
treatment plant or surface
water bodies.
Apply standards to primary
and secondary national
drinking water sources
Apply standards to landfilling
hazardous waste.
Set standards that restrict the
placement of PCBs in or on
the ground.
Set standards that restrict the
placement of certain wastes
in or on the ground.
Basis
The wastewater may be a
hazardous waste.
Wastewater may require
treatment to drinking water
standards.
Treated solids products may
still contain contaminants in
levels above required cleanup
action levels and, therefore,
be subject to the LDRs.
Treated solid products
containing less than 500 ppm
PCBs may be landfilled or
incinerated.
The nature of the waste may
be subject to the LDRs.
Response
Determine if wastewater
could be directly discharged
into a sewage treatment
plant or surface water body.
If not, the wastewater may
need further treatment to
meet discharge
requirements.
CERCLA Sections 12 1 (d)(2)
(A) and (B) explicitly mention
compliance with MCLs,
FWQC, and ACLs surface or
groundwater standards
where human exposure is to
be limited.
Treated solids products must
be sent for disposal at a
NRA-permitted hazardous
waste facility, or approval
must be obtained from EPA
to dispose of the wastes on
site.
If untreated soil contained
PCBs, then treated solids
products should be analyzed
for PCB concentration.
Approved PCB landfills or
incinerators'must be used.
The waste must be
characterized to determine if
the LDRs apply; treated
wastes must be tested and
results compared.
w
CO

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Table 2-1.  (Continued)
Process
activity
On-site/off-site disposal
(cont.)
ARAR
SARA Section 121 (d)(3)
Description
Set requirements for the off-
site disposal of wastes from
a Superfund site.
Basis
The waste is being generated
under a response action
authorized under SARA.
Response
Wastes must be sent for
disposal at a RCRA-
permitted hazardous waste
facilitv.

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highly reliable and provide long-term protection. It strongly recommends that a remedial action use an
on-site treatment that ".. ..permanently and significantly  reduces the volume,  toxicity,  or mobility  of
hazardous  substances."  In addition, general factors  which must be  addressed by CERCLA  remedial
actions  include  long-term  effectiveness and permanence,  short-term effectiveness, implementability,
and  cost.

     The TCP has demonstrated that  organic  contaminants in the feed stream can be destroyed with
at least  99.99 percent ORE. This illustrates both long-term and short-term effectiveness with respect
to organic compounds. The process  also  demonstrated  the  potential  that  heavy metals  could  be
immobilized in a non-leaching  glassy  slag  based on TCLP  analyses performed  on the coarse slag.
Similar analyses on the fine slag and the filtered clarifier bottoms, however, provided mixed  results on
heavy metals immobilization. The long-term effectiveness and permanence of the TCP  would have to
be  evaluated by subsequent  analyses that are beyond the  scope of work for  this project. It is
anticipated, however,  that the heavy metals immobilized  in the non-leaching TCP  residuals  will remain
indefinitely stable. The process wastewater streams contained  organics and heavy metals and required
additional treatment prior  to  regulated  disposal.

     The TCP is a viable  and implementable system. Texaco  is  designing a  transportable  unit  that  is
better suited  for long-term or large-scale on-site treatment.  Under such  conditions, a  fixed supply of
coal feed and an economical tie-in to a  utility or a chemical synthesis facility for the sale of the fuel gas
product could be effected.

     Based  on  the economic analysis in  Section 3, the cost of this  technology is  comparable to
alternative  thermal destruction technologies.  The unique  features of the  TCP,  however, provide  some
positive  economic incentives:

     •   The TCP is capable of remediating waste materials containing both organics and heavy metals;
        the TCP effectively destroys organics and immobilizes heavy  metals, thus eliminating the need
        for significant stabilization/solidification  treatment of a major  portion  of the  solids byproducts.
     •   The  gas emissions from the TCP are  hydrogen-rich and  economically valuable. They can be
        routed to  a  utility or  chemical synthesis plant  for  further productive  use,  thus  providing  a
        positive  cash  flow from emissions  which otherwise must be  released to the atmosphere.
                                               35

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2.1.2  Resource Conservation and Recovery Act

     The Resource Conservation and Recovery Act  (RCRA) is the primary federal legislation governing
hazardous waste  activities.  Subtitle  "C"  of  RCRA contains  requirements for  generation, transport,
treatment, storage, and disposal of hazardoues waste,  most of which are also applicable  to CERCLA
activities,

     Depending on the waste feed and the effectiveness of the treatment process, the TCP  generates
reusable fuel gas, process wastewaters, coarse slag,  fine slag, and clarifier solids. Therefore,  both
liquid and solid  residuals must be examined. The process wastewaters may contain organic   and heavy
metals;  they would require additional treatment prior to regulated disposal.  The coarse slag analyses
conducted for the  SITE Demonstration showed a  potential for  the  heavy metals  to  be  immobilized in
the non-leaching glassy slag. Similar analyses on  the fine slag and clarifier solids,  however, provided
mixed results on heavy metals immobilization.  These  solids may  exhibit RCRA hazardous waste
characteristics;  therefore, they  may require  further  permitted treatment/disposal  as hazardous.

     For generation  of any  hazardous waste,  the responsible  party for the site must obtain, an  EPA
generator identification  number and comply with accumulation and storage requirements  under 40 CFR
262, or hold a Part B Treatment, Storage, and Disposal  (TSD) permit or interim status. Compliance with
RCRA TSD  requirements is required  for CERCLA  sites. A hazardous waste  manifest must accompany
off-site shipment of waste. Transport must comply  with RCRA and Department of Transportation (DOT)
hazardous  waste  transportation regulations   The  receiving TSD  facility  must also be permitted in
compliance with RCRA standards.

     Technology (and/or concentration-based) treatment  standards have been  established for many
hazardous wastes. Those  appropriate for the TCP waste streams  will  be determined by the type of
waste generated in each operation   The RCRA land disposal  restrictions, 40 CFR 268, mandate that
hazardous wastes which do not meet the required  treatment standards receive treatment after removal
from a  contaminated  site  before land  disposal,  unless  a variance is  granted.  If either the process
wastewaters or  solids generated by the TCP constitute hazardous  wastes and do  not  meet the  land
disposal  treatment standards, additional treatment will be required  prior to  disposal.
                                              36

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2.1.3 Clean  Air Act

     The Clean Air Act (CAA) establishes  primary  and secondary  ambient air  quality  standards  for
protection of public  health  and emission  limitations for  certain  hazardous  air  pollutants.  Permitting
requirements  under the Clean Air Act are administered by each state  as part of State Implementation
Plans,  developed to bring each state into  compliance with  National  Ambient Air  Quality  Standards
(NAAQS). Air quality permits covering the operation  at MRL were obtained through  the SCAQMD. The
ambient  air quality standards  listed for specific pollutants  applied to the TCP because of its potential
emissions. The  TCP produces a synthesis gas primarily composed of hydrogen (H2), carbon  monoxide
(CO), and  carbon dioxide  (CO2).  If the  TCP were  tied to a utility or chemical synthesis facility,  this
synthesis gas could then be routed  to a gas turbine  or synthesis plant, where emissions would then be
based  on the combustion  of the gas (leaving only CO, CO2, and  nitrogen oxide (NOx) or the  resulting
emissions from  a chemical synthesis process).   It is likely, then, that a TCP built  in any state would
require an air permit. The allowable emissions would be established on a case-by-case basis, depending
upon whether or not the site is in  attainment of the  NAAQS.  If the  area is in attainment, the allowable
emission limits   could  still  be curtailed  by  the  available  increments  under Prevention  of Significant
Deterioration  (PSD) regulations. This  could  only  be  determined on a  site-by-site basis.

     Fugitive emissions are also subject to the  provisions of the  CAA.  For this SITE Demonstration,
soil from the Purity Oil Sales Superfund Site was excavated and  steps were taken  to  minimize the
impact from fugitive emissions by  watering down the soils and covering them with industrial strength
plastic prior  to drumming  and transport.   The MRL Solids Grinding  and  Slurry  Preparation  Unit
incorporates negative pressure enclosures,  nitrogen blanketing, baghouse collection of particulates, and
carbon adsorption for  organics  removal to control fugitive emissions prior to the slurrying of the  coal
and soil  with water.

2.1.4  Safe Drinking  Water Act

     The Safe  Drinking Water Act (SDWA)  establishes primary and secondary national drinking water
standards. Provisions of the Safe Drinking Water Act  apply to remediation of Superfund sites. CERCLA
Sections  121  (d)(2)(A)  and (6)  explicitly mention three kinds of surface  water or groundwater standards
with  which compliance is  potentially  required-Maximum Contaminant  Levels  (MCLs),  Federal Water
Quality  Criteria (FWQC),  and Alternate  Concentration  limits   (ACLs). CERCLA  describes  those
requirements  and how  they may be applied to Superfund  remedial actions. The  guidance is based  on
                                               37

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federal requirements and  policies; state  requirements  may  apply  even stricter standards than  those
specified in  federal regulations.

2.1.5  Clean Water Act

     The Clean Water Act  (CWA)  regulates direct discharges to  surface water through the National
Pollutant Discharge Elimination System (NPDES)  regulations.  These  regulations require  point-source
discharges of wastewater to meet  established  water quality standards. The discharge  of wastewater
to a municipal sewer requires a discharge  permit and concurrence that the wastewater is in compliance
with state and local regulatory limits.

     The TGP's wastewater streams are normally tested for hazardous characteristics and  constituents
and, if nonhazardous, are treated by  an  on-site wastewater treatment facility.  The effluent is
discharged to the  sewer if it meets  Los  Angeles County Sanitation Districts specifications.  If the
effluent does  not  meet these  specifications,  it is collected,  removed, treated, and sent for  proper
disposal  off-site. If the wastewater streams  are hazardous, they are not treated on-site. Instead,  they
are also removed, treated, and sent for disposal  in a regulated facility.

     Two process  wastewater streams, the flash  tank blowdown  and the  clarifier underflow vacuum
filtrate,  are  discharged from the  HPSGU II  to the  WWTU. At the end of each  test,  two additional
wastewater  streams-the  quench/scrubber system and  the lockhopper system water  inventories-are
also discharge to the  WWTU. Because this test  program treated a  hazardous waste as gasifier feed
material, these four water streams were  diverted to temporary storage to  allow removal by vacuum
truck for off-site treatment and disposal. A  fifth process wastewater stream containing sodium sulfate
and sodium thiosulfate was  generated  by the  Sulfur  Removal Unit.  This  stream did  not  exhibit
hazardous characteristics  as a result of gasifying a hazardous waste. As with the  other wastewater
streams, this  stream  was  diverted to  storage,  followed  by off-site  treatment and disposal.  Water
generated from washing down the process units, normally discharged to the WWTU via a sump system,
was also removed  by vacuum truck for off-site treatment  and disposal.

2.1.6  Toxic  Substances  Control Act

      The disposal  of PCBs is  regulated  under Section 6(e) of the Toxic Substances Control Act of 1976
(TSCA).  PCB treatment  and  disposal  regulations are described in 40  CFR  Part 761. Materials
                                                38

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containing  PCBs  in  concentrations between 50 and 500 ppm  may either be sent to TSCA-permitted
landfills  or destroyed by incineration at a TSCA-approved  incinerator. At concentrations greater than  500
ppm, the material must be incinerated.  Sites where spills of PCBs have occurred after May 4, 1987, must
be addressed  under  the PCB Spill Cleanup Policy in 40 CFR Part 761,  Subpart G.  The policy applies to
spills of materials  containing  50 ppm or greater of PCBs and  establishes  cleanup protocols for addressing
such releases, based upon the volume and the concentration of the spilled material.

     According to Texaco, the TCP is an effective  thermal destruction system capable  of  treating both
solid and liquid wastes containing PCBs. If the TCP is to be used  to treat PCB-contaminated material,
TSCA authorization defining  operational, throughput and/or disposal constraints  is required.  If the PCB-
contaminated material contains RCRA wastes, RCRA compliance is also required.

2.1.7    Occupational Safety and Health Administration Requirements

     CERCLA remedial  actions and RCRA corrective  actions  must be performed  in accordance with OSHA
requirements detailed in  20  CFR  Parts 1900  through  1926,  especially Part 1910.120, which provides for
the health and safety of workers  at hazardous waste sites.  On-site construction activities at Super-fund
or RCRA corrective action sites must be performed in accordance with Part 1926 of OSHA, which provides
safety and  health regulations for construction  sites. State OSHA  requirements, which  may be significantly
stricter than federal standards,  must also be  met.

     All technicians  operating the TCP on waste feeds are required to have  completed and maintained
OSHA hazardous waste operations training. They  must be familiar with all OSHA  requirements relevant
to hazardous waste  sites. For  most sites, minimum  personal protective  equipment (PPE)  for technicians
will include  gloves,  hard hats,  steel toe boots,  and flame-retardant  coveralls. Depending on contaminant
types and concentrations, additional PPE may be required.

     A required health and safety plan for all  TCP operations defines the operational site, health  and
safety personnel responsibilities, chemical and physical hazard assessments, PPE, site control and  hazard-
zone  definition, decontamination  procedures, exposure  monitoring  for chemical  and physical  variables,
recordkeeping, and specific  material  safety data sheets for all site-related  chemicals  of concern.
                                                39

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2.2 OPERABILITY OF THE  TECHNOLOGY

     During the one-week period  scheduled for the SITE Demonstration tests a major earthquake and
three operational problems impacted the scheduling and operation of the test runs.

     The earthquake on January  17,  1994 caused  an  overall shutdown of MRL. The facility sustained
minor piping, equipment, and  instrument damage  that required overall  repairs, and recalibration. The
shutdown required  a rescheduling of the system preheat, equilibration, and startup sequence and
protocol. These changes delayed the planned SITE Test Run No. 1 from January 18,1994 to January
19, 1994.

     Three operational  problems  caused  no significant delay

     1.        Plugging of the organic (POHC) spike injection line.
     2.        Unstable gasifier operation during  Run No. 3.
     3.        A tear in the fine slag vacuum filter belt during Run No. 3.

     In  all three incidents, actions by MRL personnel successfully addressed the problems to complete
the SITE test runs with minimal delay, no process interruption, and minor interference with the test
sampling activities.

     The plugging of the spike injection line occurred during the startup sequence for Run No.  1. Two
POHC spiking compounds-chlorobenzene (VOC) and  hexachlorobenzene(SVOC)-- were originally
planned.  A  heated system was designed by Texaco to ensure the complete dissolution  of the
crystalline-solid  hexachlorobenzene in the liquid chlorobenzene. Even  though the entire system was
heated and steam-traced, apparently either the temperature or flow of the solution was low enough in
the piping to cause  recrystallization of the hexachlorobenzene which plugged the line. After several
hours of unsuccessfully attempting to establish a continuous flow, further delays appeared to jeopardize
the SITE test runs.  The POHC spike solution  composition was revised to eliminate the  SVOC
hexachlorobenzene.  This change would still allow the  SITE tests to measure the ability of the TGP to
achieve a 99.99 percent ORE on the  remaining chlorobentene VOC POHC. The initiation of Run No.
1, however, was further delayed from January 19, 1994 to January 20, 1994.
                                             40

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     The unstable gasifier operation, which caused gasifier operating temperatures to increase and
sampling activities to be suspended during a 1 -hour period of Run No. 3, was apparently caused by the
formation of a solid deposit at the slurry feed injector outlet in the gasifier. The solid deposit was
shaken  loose by a large pulse of nitrogen after which gasifier conditions  returned to normal.

     The torn filter belt on the fine slag vacuum filter was replaced by maintenance staff during a 4-
hour period of Run No. 3 and the filter was returned to service with no unit or SITE sampling shutdown.

     None of the above-mentioned incidents were considered  substantial episodes affecting critical
reliability or  maintainability.  The earthquake confirmed the structural integrity of the TGP system,
which experienced only minor  damage.  The plugging of the spike injection line was specific to the
attempt to introduce hexachlorobentene for ORE determination, therefore, it will not occur during
commercial operation. The gasifier feed injector solid deposit, which caused the gasifier in stability and
a rise in operating temperature, was eliminated by operator intervention based on past experience. A
torn filter belt on a fine slag vacuum filter is an infrequent but routine maintenance issue. Intermittent
operations, length of time in service, and a misalignment of the belt scraper (possibly caused by the
earthquake) may have contributed to the belt failure.  In any event the belt failure did not affect gasifier
operation and only impacted the recovery of the fine slag which was then collected in slurry form.

     Based on the minimal delays and interruption caused by the above-mentioned incidents and the
continuity of operations exhibited  during the overall two-week Demonstration period, it is expected that
the reliability  and efficiency of the TGP will  be consistently high and TGP operations will maintain  on-
stream  efficiencies of approximately 80 percent allowing for routine maintenance and intermittent,
unscheduled  shutdowns. Two  potential process area maintenance problems include solids  handling
equipment, where the variations  and abrasive nature of the coal, soil, and slag matrices may cause
above-average wear,  and the gasification section, where the high temperatures and pressures provide
a difficult environment for equipment operation.

     During the three SITE test runs, approximately 40 tons of slurry were treated in the TGP. The
total amount of slurry treated during the entire Demonstration period of two weeks, which included
scoping runs,  initial shakedown, system start-up, a pretest run, the three  replicate test runs  and post-
demonstration processing  of the  slurry inventory,  was approximately 100 tons.
                                              41

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2.3  APPLICABLE WASTES

      The versatile TCP can process a variety of waste streams. Virtually any carbonaceous, hazardous,
or non-hazardous waste stream can be  processed in the TCP if the pretreatment facilities for storage,
grinding, screening,  and slurrying are adequate  to  handle  and treat the  incoming  material.  Physical
characteristics-such as particle size and the viscous  or sludge-like nature  of the matrix-and chemical
properties-such as  pH and moisture content-will  directly impact on  the  ability  of the TCP equipment
to effectively slurry the waste feed.

      The TCP test facility at  MRL, where the SITE demonstration was conducted, is equipped with a
hammer mill for coal crushing, a wet rod mill for waste/coal/water slurrying, and various silos, hoppers,
conveyor belts, bucket elevators, and storage tanks to support the movement and storage of the waste,
coal, and slurry feed. The  Purity Oil Sales Superfund Site soil, excavated for treatment in the TCP, was
site-treated with lime to a  pH greater than 4 and screened to a  particle size less than % inch for easier
processing by the MRL materials-handling and slurrying systems.

      Depending upon its  physical and chemical composition, the  waste  stream can  either be used as
the primary gasifier feed or a portion of the mix, combined with a high-Btu fuel such as coal, petroleum
coke, or oil.  The combined feed  must  be  capable  of being slurried, have a  heating value that can
maintain gasifier temperatures,  and produce an ash  with  a fusion  temperature that  falls  within
operational  limits.

      The ratio of waste feed to fuel can be adjusted to optimize the gasifier operation. Even if a waste
stream can be used as the sole  feed to the gasifier, blending  the waste with a high-Btu feed or fuel
ensures  continuity and stability of operation.

      The TCP can treat wastes that fall into three categories:

      (1)       Solid  or liquid  wastes that  contain sufficient  energy to sustain gasifier operation as the
               sole feed  without  adding another  higher-heating-value fuel.
      (2)       Solid  wastes  with  heating values too low  to  sustain gasifier  operation  that can  be
               supplemented  by a higher-heating-value fuel, such as coal.
                                               42

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     (3)        Liquid  waste with insufficient heating values that can  be combined with  a higher-
               heating- value fuel. In this case the liquid waste  can be used as the fluid phase of the
               primary feed slurry.

     The TCP has operated commercially for nearly 45 years on feeds such as natural gas and coal,
and  non-hazardous wastes such  as  liquid petroleum fractions, and  petroleum coke. Texaco's patented
gasification process is currently licensed in the U.S. and abroad.  The syngas is  used for the production
of electric power  and  numerous chemical  products, such  as ammonia,  methanol  and  high-purity
hydrogen. As  an innovative process gasifying less traditional and  hazardous  wastes,  Texaco  reports
that  the  TCP  has processed various waste matrices containing a  broad  range of  hydrocarbon
compounds  including  coal  liquefaction  residues,  California  hazardous waste material from an  oil
production field (petroleum  production  tank bottoms),  municipal  sewage sludge, waste  oil, used
automobile tires, waste plastics,  and  low-Btu soil.  Texaco  licensees in Europe  have had long-term
success  in gasifying small quantities of hazardous waste as supplemental feedstock  including  PCBs,
chlorinated hydrocarbons,  styrene distillation bottoms, and waste  motor oil.

     Texaco expects to design TCP facilities with flexible and comprehensive storage and pretreatment
systems  capable of processing a wide range of waste matrices slurried with  coal or oil, water, and
additives. If the specific waste exhibits some unusual physical  or chemical characteristics  that would
affect the ability of the pretreatment module to slurry the feed,  additional  equipment may supplement
the existing  design.

2.4 KEY FEATURES

     The TCP  is  uniquely different from conventional  thermal destruction technologies,  particularly
incineration,  in several key process and design areas.

     •  The TCP is a gasification process operating with a limited amount  of oxygen (partial oxidation)
       at high temperature  and pressure. Because gasification is a  reducing process using oxygen, the
       production of sulfur  oxide (SOx) and NOx  is minimized.

     •  The centerpiece  of the  TCP is  a proprietary  entrained-bed gasifier with  concurrent flow of
       oxygen  and hydrocarbon  fuel.
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     •  The waste matrix can be wet or dry,  and according to the design of the pretreatment system,
       requires no other specification.  The slurry waste feed, mixed with  coal, water and any  other
       supplemental  stream,  is safer and  easier to  control than a dry system. This allows Texaco to
       customize the feed to ensure  proper slurrying,  storage, pumpability, adequate feed heating
       value,  gasifier temperature  maintainability, optimum slag  fusion, and  proper production
       conditions.

     •  The TCP destroys organic contaminants to regulatory DREs and  can potentially immobilize
       heavy metals in a glassy  coarse slag.

     •  The TCP produces a usable and economically viable gas stream (syngas) containing hydrogen
       and carbon monoxide which can be used for further  chemical synthesis and electrical  power
       generation.

     •  The TCP, currently designed and  operating as large capacity stationary units, is also  being
       designed as a transportable unit for on-site  remediation.

2.5  AVAILABILITY AND TRANSPORTABILITY OF EQUIPMENT

     The SITE  Demonstration of the TCP  was conducted at the MRL using permanent multi-purpose
gasification  research  facilities.   This  research  and  development laboratory,  with three pilot-scale
gasification  units, ancillary units, miscellaneous equipment,  offices,  and other  support facilities
comprises a fixed-sited area of approximately 10 acres.

     Texaco  is  completing the design of a skid-mounted  transportable unit  capable of treating
hazardous waste on-site,  eliminating the need  to transport contaminated waste from a hazardous waste
site to  a fixed treatment facility. The capacity  of the  proposed unit is  based on a dry syngas flow rate
of 4.2  million scf/day. The quantity of waste  that could be treated  would be  approximately 100 tpd
depending on the composition of the waste.

     Skid-mounted components could be constructed in  about 24  months;  they would be  mounted on
multiple transportable trailers.  The size and configuration  of this equipment  is based on  operating
conditions determined at  the MRL. Materials-handling equipment may require modifications to process
specific waste  matrices as discussed earlier and summarized below.  Syngas product usage would  be
                                              44

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determined on a case-by-case basis. Water streams might receive some treatment, but may have to
be removed with the solid  products as hazardous waste.

2.6 MATERIALS  HANDLING  REQUIREMENTS

     As discussed in  Section 2.3, the TGP is flexible and can process virtually any carbonaceous
hazardous or non-hazardous waste stream. The waste material, however, either as the primary feed
to the gasifier or combined with a high-Btu fuel such as coal, petroleum, coke, or oil must be capable
of being slurried, have a heating value that can maintain gasifier temperatures, and produce an ash with
a fusion temperature that falls within operational  limits.

     Based on the ability of the TGP to accept such  a wide range of wastes, materials-handling
requirements are dictated by the  physical and chemical characteristics of the waste matrix to be
slurried. Additional  equipment may be required to supplement the existing design of the transportable
unit's materials-handling system.

     At the waste or Superfund site, contaminated soil will  need to be excavated, staged,  transported,
and loaded into the TGP. Soil should be kept wet and covered with  industrial strength  plastic to
prevent fugitive emissions of particulates.   Where VOCs are primary contaminants, soil should be
handled within an enclosed system.

2.7 SITE SUPPORT REQUIREMENTS

     The TGP support requirements include site conditions (surface, subsurface, clearance, area,
topography, climate, and  geography),  utilities, facilities, and equipment.

     For a proposed 100-tpd transportable unit,  surface  requirements would  include a level,  graded area
capable of supporting the equipment and the structures housing it. The complexity and  mechanical
structure of a high-temperature, high-pressure TGP  unit  mandate a level and stable  location. The unit
cannot be deployed in areas where fragile geologic formations could be disturbed by heavy loads or
vibrational stress. Foundations must support the weight of the gasifier  system, which is  estimated at
50 tons, as well as other TGP support facilities and equipment. The transportable TGP unit would
weigh approximately 300 tons and consist of multiple skid-mounted trailers requiring stable access
roads that can  accommodate oversized  and  heavy  equipment.

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     The transportable 100-tpd TGP unit would require an area of approximately 40,000 square feet
(ft2) (275 ft x 150 ft), with height clearances of up to 70 feet. This area should accommodate all TGP
process  operations, although additional space  could be needed for special feed preparation and
waste/residuals  storage facilities.

     The transportable TGP unit could be used in a broad  range of different climates. Although
prolonged  periods of freezing temperatures might interfere with soil excavation and handling, coal
handling, slurry preparation, and water-related operations, they would not affect a TGP design that
incorporates adequate  heating, insulating, and  heat-tracing capabilities at  critical locations.

     The proposed transportable I00-tpd TGP unit would  require the following utilities: 91 tpd of
oxygen,  39 tpd of coal, 5 tpd of lime, 410 kilowatthours per hour (kWh/h)  of electrical power, 40
gallons per minute (gpm) of make-up water, and  less than 1 tpd of nitrogen.

     Support facilities would include staging areas for contaminated soil and coal prior to pretreatment,
materials-handling, and slurry preparation. Syngas  product would be routed by pipeline directly off-site
without any support facilities for  storage or transport. Solid  products would be stored  in roll-off bins.
Wastewater would be  collected in appropriate tank storage.  All support facilities  must  be designed  to
control run-off and  fugitive emissions.  Support equipment would include excavation/transport
equipment  such as  backhoes, front-end  loaders,  dump trucks, roll-off bins, and storage tanks.

2.8 LIMITATIONS OF THE  TECHNOLOGY

     The TGP can  process virtually all waste stream matrices based on the availability of adequate
materials-handling,  pretreatment, and  slurrying equipment.

     The unit's complexity and costs, and  preferred tie-in to a syngas  user mandate that on-site
remediations be limited to relatively large sites and long-term  remediations with a minimum of 50,000
tons of waste feed and about two years of operation. A tie-in for the TGP syngas product, such as to
a gas  turbine electrical generation set or to a manufacturing facility may also affect TGP siting.
                                              46

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                                         SECTION 3
                                   ECONOMIC ANALYSIS

     Estimating  the  cost of employing an  innovative technology is  a major objective in  each SITE
Demonstration  project.  This economic analysis  presents  data  on the costs (excluding profit) for
commercial-scale remediations using the Texaco Gasification  Process  (TCP).  Data were compiled during
the SITE Demonstration tests conducted  at the Texaco  Montebello  Research Laboratory  (MRL) pilot
facility. This pilot facility is  only  used to  optimize operating conditions for  the design of commercial
units; the SITE Demonstration was conducted in the same  manner to  determine the commercial design
on which this economic analysis is  based.  With  a realistic understanding  of, and accounting  for the
Demonstration test results and costs,  the following economic  analysis extrapolates these test  results
and  costs for larger  proposed commercial systems at other  sites.

3.1  CONCLUSIONS OF ECONOMIC ANALYSIS

     This analysis presents the costs of treating contaminated sites, each containing 100,000 tons of
soil.  The  analysis is based on a transportable TCP unit capable of processing 100 tpd  of waste soil on-
site.  An analysis for  a stationary, centralized TCP facility designed to process 200  tpd  of waste soil
transported to a  central plant is  also presented.  Table 3-1  presents a breakdown of costs per ton  of
soil into 12 standard cost categories,  as  defined in Section 3.2.

     The two cases illustrate the need for a  commercial TCP unit to operate for several years on large,
high-contaminated-soil-volume  sites at  high  unit capacity.   This  is necessary to  overcome the
complexity and high costs of the  TCP design and  operation and to take advantage of the value of the
TCP syngas product  as a useable and  marketable commodity.
                                              47

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                     Table 3-1.  Treatment Costs Associated with the TOP
Unit
Soil, tpd design
Soil, tpy actual
Online % utilization factor
Years online leach site)
Capital, $ million
Ontite TGP
100
29.200
80
3.42
11.0
100
25,550
70
3.91
11.0
Central TGP
200
58,400
80
15
22.0
200
51,100
70
15
22.0
Cost categories, $/ton
Site preparation
Permitting/regulator
Capital equipment
Start-up
Labor
Consumables and supplies
Oxygen
Chemicals
Coal
Lime
Utilities
Effluent treatment/disposal
Residuals
Slag
Syngas
Analytical services
Maintenance
Demobilization
Total, $/ton
--
--
$64.26
$25.00
$52.60
$54.60
$5.00
$15.56
$2.00
$6.81
$65.80
$2.74
($7.24)
$5.00
$11.30
$5.00
$308.43
--
--
$64.26
$25.00
$60.12
$54.60
$5.00
$15.56
$2.00
$6.81
$65.80
$2.74
($7.24)
$5.00
$12.92
$5.00
$317.56
-
-
$44.01
$0.00
$26.30
$54.60
$5.00
$15.58
$2.00
$6.81
$65.80
$2.74
($14.48)
$5.00
$11.30
$0.00
$224.64
..
-
$50.30
$0.00
$30.06
$54.60
$5.00
$15.56
$2.00
$6.81
$65.80
52.74
($14.48)
$5.00
$12.92
$0.00
$236.31
     The estimated treatment costs, at 80 percent and 70 percent utilization factors, respectively,
ranged from $308 to $318 per ton of soil for the I00-tpd transportable unit and from $225 to $236
per ton for the 200-tpd stationary centralized facility. The estimates presented in this analysis may
range in accuracy from +50 percent to -30 percent.
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3.2 BASIS OF ECONOMIC ANALYSIS

     In addition to developing effective cost data, the major objectives of this SITE Demonstration were
to demonstrate, on  a RCRA-designated hazardous waste feed, the  potential of the TCP to produce a
useabl e syngas product, destroy organic compounds, and produce non-hazardous, inert glass-like slag
byproducts.  The Demonstration test slurry, which consisted  of Purity Oil  Sales Superfund Site waste
soil mixed with other slurry materials including clean soil, coal,  water, and heavy metals  (specifically
lead and barium nitrate)   and organic (chlorobenzene)  spike  compounds,  demonstrated the  potential of
the TCP to  meet  all of the objectives  in a reliable and cost-effective manner and its applicability to the
remediation  of sites contaminated with both organic and heavy  metal compounds.

     For  the Demonstration  test, three  runs were  conducted,  over  a two-day  period,  treating
approximately 40 tons of slurry. Solid feed rates during the Demonstration  averaged  16  tpd. These
feed rates and  the  overall design and size of the pilot facility at  MRL are for  research-testing and are
not practical for an  on-site cleanup or a commercial facility where higher throughputs  are required for
cost effectiveness.

     The proposed  Texaco-designed transportable TCP is sized to process hazardous soils and sludges
at a rate  of 100  tpd of waste  solids, which  is a six-fold  increase  over  the Demonstration pilot test
facility  and is considered  a  minimum  capacity for economical and  on-site remediation operation. This
comparatively small TCP unit falls within the size range of several currently operating  units but is less
than one-tenth  the  size of the largest operating  TCP unit   The TCP's complexity,  costs,  and the
economic benefit of a tie-in to its syngas product  mandate that  on-site remediations  be limited  to
relatively large sites with a minimum of 50,000 tons of waste feed and about two years of operation.
This commercial transportable TCP    would be operated under conditions defined by the performance
data from the SITE Demonstration and applied to a  commercial  design that maximizes the amount of
contaminated soil (hazardous waste throughput) in the overall slurry feed.

     Because the complexity,  costs,  and tie-in to a  syngas user mandate a large site remediation, an
alternative, 200-tpd  stationary centralized TCP facility has also  been designed and costed  as part of
the economic analysis.

     To provide a basis of cost-effectiveness comparison among technologies, the SITE Program links
costs to 12  standard cost categories, listed below:
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     • Site preparation
     • Permitting  and regulatory requirements
     • Capital equipment
     • Start-up
     • Labor
     • Consumables and supplies
     • Utilities
     • Effluent treatment and disposal
     • Residuals
     • Analytical  services
     • Maintenance
     • Demobilization

     Some  of the cost categories above do not  apply to this analysis because they are  site-specific,
project-specific, or the obligation of  site owner/responsible  party.

     All of these cost categories are defined and discussed in Section 3.4 -  Results

3.3 ISSUES AND ASSUMPTIONS

     This analysis is based on the operating results obtained during the SITE Demonstration at the MRL
pilot facility using a slurry feed containing  Purity Oil Sales Superfund  Site waste soil. The pilot facility
is used for demonstrations and to optimize  operating conditions but due to its small lockhopper and slag
handling capacity (ash handling capacity),  soil throughput had to be maintained at rates that are lower
than actual scaled-up soil feed rates proposed for commercial units. The SITE  Demonstration processed
a slurry containing over 40 weight-percent coal  and approximately  17 weight-percent soil  producing
a slurry containing 62.5 weight-percent  solids.  The commercial transportable  100-tpd  unit is designed
to  process a slurry containing less than 20  weight-percent  coal and  over 40 weight-percent soil,  but
the same  62.5 weight-percent solids  used  in  the SITE Demonstration.  Since  the commercial units are
being designed for cost-effective site remediations,  soil throughputs have been maximized and  are
higher than  the pilot facility feed rates.  With higher soil throughputs and lower coal feed rates, feed
slurries will have  lower heat contents. Commercial units will consume higher  quantities of oxygen  and
auxiliary fuel per ton  of soil to offset lower heating  values, but overall unit  costs per ton of soil  will
improve  based on increased  soil throughputs.    For this analysis, which is  based on  the SITE
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Demonstration test, the waste feed soil is assumed to  have the same comparatively high heating value
as the Purity Oil  Sales  Superfund Site  soil because of its contamination with high-heating-value waste
oil.  This  high  heating value  offsets the need to supplement the feed with auxiliary  fuel to maintain
gasifier operation. Other soils may not  have as high a heating value and will  require  additional  oxygen
and  auxiliary fuel.

     The SITE Demonstration tests produced a useable and potentially marketable medium-Btu syngas.
Any  proposed site cleanup  using  the  TCP  should  incorporate  the practical end-use  of the  syngas
product.  The simplest use for the syngas is as a  fuel gas for steam production or power generation.
For this  analysis  the syngas  is assumed to be routed off-site without any  support facilities for storage,
transport, or use as a fuel gas.  Further discussions  on the  planned or currently operating plant  uses
of the  syngas  are presented  in the Vendor Claims -  Appendix I.

     The proposed 100-tpd  transportable unit, as  defined in this analysis, is designed for a  15-year
service life.  For such a large and complex unit, relocation costs  are high;  a more practical investment
may be the construction and operation  of a stationary unit at a central facility for the  entire service life
of the  equipment, which although assumed to be similar to the 15-year life of the transportable design
for  a comparative analysis, could be 30 years.

     The transportable  100-tpd  unit and the stationary 200-tpd unit are assumed to  operate 24 hours
a day, 7 days a week, 292 days a year (at an 80 percent utilization factor for 3.42 years) or 255 days
a year (at 70  percent utilization  factor for 3.91 years) to  remediate 100,000 tons of contaminated soil.
The transportable unit is assumed to operate for about 4 years at each of 3 sites during its  15-year life.
The stationary unit will  operate  at  a fixed site for  15 years.

      Specific  issues and  assumptions  as  they  relate 'to each of the standard cost categories are
presented below.

3.4 RESULTS

3.4.1  Site  Preparation Costs

      The costs  for excavation, transportation, and pretreatment of a contaminated  waste  matrix  are
highly variable.  The type of contaminated  matrix  (i.e., dry soil  vs.  sticky sludge),  the  amount of
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extraneous  debris that  must  be separated from  the  matrix,  and  the contaminant types  and
concentrations are  several variables that will impact on  excavation, transportation, and pretreatment
costs.   Cost for  waste handling,  and temporary  roads and  facilities that may be required are not
included because they are site-specific. The  costs for foundations, utilities, and  equipment erection for
TCP systems were  estimated and are included under the capital equipment and startup  cost categories.

3.4.2  Permitting  and  Regulatory  Requirements

     The costs for  permitting are not included. These may include federal, state, and local permits and
will vary with  each project and are generally the obligation  of  the  site owner or responsible party.
Depending on the  site, these costs could be significant.   The obtaining  of these permits can also be
extremely time-consuming. The stationary facility, for example, may  require the  expenditure  of several
hundred thousand dollars  and a year of application, operation,  and reporting activities in order to obtain
an  operating permit to process RCRA-designated hazardous waste.  The monitoring  and  analytical
protocols  that would be required on an  ongoing  basis  to  support permit and regulatory requirements
during  operation have  been estimated  and are jncluded  under analytical services.

3.4.3  Capital  Equipment

     The capital  costs are based  in  part on a comprehensive  1993 cost estimate,  prepared by an
engineering  design  firm, for a I00-tpd  transportable TCP unit. A portion  of the installed equipment,
including materials handling for the feed preparation and the gas cleaning and wastewater treating, was
estimated by Texaco. The costs of the 200-tpd stationary unit were factored from the  costs developed
for the  I00-tpd  transportable unit.

     It is assumed that the transportable unit would operate at 3 sites over its 15-year life. The capital
costs are based on amortization over 15 years at  8% interest with no tax considerations and  no scrap
value.  The annual capital recovery (amortization) factor is  0.11683 and the total was  allocated evenly
between the 3 sites.

     The components of the capital cost for the 100-tpd  transportable  unit are presented in Table 3-2
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                        Table  3-2. Capital  Costs for  the TCP Unit
a.
b.
c.
d.
e.
f.
P.
h.
i.
i.
k.
Feed receiving and storage
Grinding and slurry preparation
Gasification
Lockhopper
Syngas cleaning
Sulfur removal
Slag and solids handling
Wastewater treatment
Control system
Utilities and support facilities
Engineering
Total cost
$1 ,000.000
700,000
1,600,000
800,000
600,000
1,900,000
400,000
300,000
700,000
1 ,000,00
2,000,000
$11 ,000,000
3.4.4  Startup

     The startup costs are for the labor and contracts for site preparation, equipment installation, utility
service  connections,  and  equipment check-out.   The 100-tpd  transportable  unit will  occupy
approximately an acre  and will require  16 weeks for  installation.  The  major contracts  will  be for
foundations  and slabs, equipment and  structural  erection, electrical systems,  and controls  and
instrumentation.  The total is estimated at $2,500,000  per site.

     Most  of the  components for  the transportable  TCP will be  shipped in  factory-built, structural
modules. The largest of these  will  be  14 ft by 14 ft  by 42 ft long. Transportation was estimated on
the basis of relocation from the unit's home-base in Texas to a remediation site in California or  Illinois.

     The startup costs for the central  plant  are one-time costs and  are included in  the  capital
equipment.
                                               53

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3.4.5  Labor

      Labor costs are based  on six-man crews for each of four shifts per week. The cost for the total
staff of 24,  at  an  average  all-in cost  per  hour of $32.00  or  $64,000 per  year  per employee is
$ 1,536, 000 per year for both  the transportable and stationary units and is independent of the utilization
factor

3.4.6 Consumables and  Supplies

     The major costs are for  oxygen and coal.  Oxygen  cost is estimated  at  $60.00  per ton  and is
expected to be  consumed at the  rate of 0.91 tons per ton of soil. The  cost for site-delivered coal  is
estimated at $40 per ton and is expected to  be consumed at a rate of 0.39  tons per ton of soil. Lime
addition,  at  a rate of 0.05 tons per ton  of soil, is estimated at $40 per ton.  The costs  for gas treating
chemicals are $5.00 per ton  of soil.

3.4.7  Utilities

     The cost for  electric power  is estimated at $0.06/kWh. The  water charge is  $1.50 per 1,000
gallons. The stationary  plant utilities  were  estimated at the  same  rate per ton of soil.  The  I00-tpd
transportable unit utilities  consumption were  estimated to  be $410 kWh/h  of electrical power and 40
gpm of make-up water.

3.4.8  Effluent Treatment and  Disposal

     Disposal costs  are  estimated  for the  wastewater,  hazardous  clarifier bottoms,  and fine  slag
effluents. The syngas product and  potentially  non-hazardous coarse slag  economics are defined in the
residuals cost section of this discussion. Effluent treatment costs, including  wastewater treatment, are
included  in  other categories as part of the  operating  process.   The  one-time SITE Demonstration
disposal  cost  for clarifier bottoms and  fine  slag was $230  per ton. For  a  continuous commercial
operation, it is assumed that a more cost-effective disposal  cost can be negotiated. At 87.7 tons of
solids per 100 tons of soil,  of  which  62.5 weight-percent  is  non-hazardous  coarse slag, the disposal
of the 32.9  tpd of the hazardous portion at $200 per ton  is  $65.80 per ton of soil.
                                               54

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3.4.9   Residuals and Waste Shipping and Handling

     The  potentially non-hazardous coarse slag can be  sold  for the cost of transportation from the
proposed stationary plant as road or building-block aggregate or returned to the site in the transportable
unit case. Nonetheless, to be conservative, a cost of $5 per ton or $2.74  per ton of soil for the coarse
slag  handling and transport is included for the 62.5 weight-percent of the solids that are non-hazardous.

     The  syngas product can be valued on a par with natural  gas for the transportable unit case and
at a  higher value  for the stationary plant based on its hydrogen  and carbon  monoxide content. The
value of the syngas is estimated  at $1  .00  per million Btu for the transportable unit and $2.00 per million
Btu for the stationary plant. The  process, storage,  and transport equipment and facilities for the syngas
are not included in these cost estimates.

3.4.10 Analytical  Services

     This cost is based on the sampling and TCLP testing of the solid and liquid effluents and residuals
by an independent laboratory on a  periodic basis.  Tests for  lead and several other species, two to four
times per day, are estimated to  cost  $60 to  $75.per  sample and  may add up to $5 per ton of waste
processed

3.4.11  Maintenance and  Modifications

     Maintenance  costs are estimated at 3% of the capital cost per year.  This  is based on an average
of previous DOE studies for a large stationary TGP/combined-cycle power plant at 1.5% of capital cost
and actual MRL  maintenance costs budgeted at 5% per year.

3.4.12 Demobilization

     Site  demobilization for a transportable unit is assumed to cost a flat  $500,000. This is intended
to cover  all labor  and  contracts to close and leave a cleanup site. There is no cost assumed for
demobilization at the stationary  plant.
                                               55

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                                        SECTION  4
                              TREATMENT   EFFECTIVENESS

     Results  of the TCP SITE Demonstration  relate to  the three primary  technical  objectives listed
below:

     •        Achieve  99.99 percent DREs for specific  principal organic  hazardous constituents
              (POHCs).

     •        Produce  a  non-hazardous  primary  solid residual -coarse slag  -and  secondary solid
              residuals-fine  slag and clarifier  bottoms.

     •        Produce  a synthesis gas (syngas)  product composed primarily  of hydrogen and carbon
              monoxide that will be  usable as a clean fuel source for the production  of  electrical
              power or raw material for chemical manufacturing.

     Additionally,  the  Demonstration  test data  were  evaluated to determine two other measures of
applicability:

     •        Overall capital and operating costs for the TCP, including  the  value  of the resulting
              synthesis gas  product.

     •        The reliability and efficiency of the TCP and  its operations  throughout  the  SITE
              Demonstration.

4.1  INTRODUCTION

     Prior to the  SITE tests, soil from the Purity Oil Sales Superfund  Site in Fresno, California was
characterized and evaluated as a potential source of hazardous  waste material. Based on constraints
                                              56

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imposed by the State  of California under a variance to  permitted operations at MRL, the waste feed
material could not exhibit  characteristics  that would define the soil  as  hazardous under RCRA.  Based
on this regulatory constraint, excavated soil, treated with lime and  prescreened, was analyzed to ensure
that it met the TCLP criteria for lead  (5 mg/kg) and  contained less than 1,000 mg/kg total lead.

     To assess the TCP operation and its ability  to process a RCRA-designated hazardous waste feed
that does  not comply with  TCLP  and WET-STLC regulatory limits,  non-RCRA hazardous  soil from the
Purity Oil  Sales Superfund  Site in Fresno,  California was spiked with  lead nitrate and barium  nitrate
during  slurry preparation to create a  surrogate RCRA-hazardous waste feed. For the extended SITE
Demonstration,  additional slurry was required and prepared using  a  mixture of clean soil and  oil spiked
with barium nitrate since further supplies  of Purity Oil soil could not be  obtained.  To ensure a sufficient
concentration of the  designated POHC for ORE determination, chlorobenzene was added  to  the Purity
Oil/clean soil mixed test  slurry at the slurry feed  line  to the  gasifier. Table  4-I shows the  overall
composition of  the mixed,  spiked  test slurry processed  during the  TCP SITE Demonstration.

     Three runs were  conducted over a two-day period, treating approximately 40 tons of slurry.  The
total amount of slurry treated during the  entire  Demonstration  (scoping  runs,  initial shakedown, system
startup, a  pretest  run, the three replicate runs;  and  post-demonstration  processing  of the slurry
inventory) was  approximately  100 tons.  The following critical  process  and chemical  parameters were
measured and analyzed.

     Process Parameters

     •        Slurry  feed  rate
     •        Raw syngas, flash gas, and fuel  gas flow rates
     •        Make-up and  effluent water flow rates  (except  neutralized wastewater)
     •        Weight of coarse slag, fine  slag,  and clarifier solids
     o        Organic spike flow rate

     Chemical/Analytical  Parameters

     •        VOCs,  PCDD/PCDF,  and metals  in all feed and discharge streams (except neutralized
               wastewater)
                                                57

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                       Table 4-1   Composition of Demonstration Slurry Feed

Pittsburgh #8 coal
Havoline SAE 30 oil
L.A. County soil
Fresno County soil
Purity Oil soil
Water
Gypsum
Surfactant
Barium nitrate
Lead nitrate
TOTAL
Slurry, pounds CISJ
Purity Oil soil
10,511
—
...
...
5,264
10,529
—
21
330
145
26,800
Clean soil
56,280
2,050
11,000
11,080
...
54,000
2,500
130
1,000
...
138,040
Total mixed*
66,791
2.050
11,000
11,080
5,264
64,529
2,500
151
1,330
145
164.840
        The total slurry feed does not include the chlorobenzene organic spike (L-6) that was added (at approximately
        3,150 milligrams per kilogram (mg/kg) based on'slurry flow) to the total mixed slurry flow to the gasifier at 6.20,
        6.30, and 6.75 pounds per hour (Ib/h) for Runs 1, 2, and 3, respectively.
     •         TCLP and WET-STLC analyses on waste feed, slurry feed, coarse slag, fine slag, and
               clarifier solids
     •         Process gas stream  compositions


4.2  ORE


     The ORE was the measure of organic destruction and removal efficiency during the Demonstration
Test. This parameter is determined by analyzing the concentration of the POHC in the feed  slurry and
the effluent gas stream(s).  For a given POHC, ORE is defined as follows:
               WIN - WOUT
        ORE = 	x  100%
                   WIN
                                                 58

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Where
     W1N  =     Mass feed rate of the POHC of interest in the waste stream feed
     WOUT =   Mass emission rate of  the  same POHC present in  the effluent gas streams prior to
               release to the flare.

     For these TCP SITE tests,  DREs  were calculated in two ways. For the gasification process, the
effluent gas streams included the raw syngas and flash gas; for the overall TCP operation, the effluent
gas streams included the fuel gas, the  absorber off-gas, and oxidizer off-gas. The POHC identified for
the Demonstration  was chlorobenzene.  This  compound was selected as a representative thermally
stable  compound for the purpose of evaluating the TCP's  ability  to destroy organic compounds. As
shown in Table 4-2, all calculated  DREs were  greater than  99.99  percent for chlorobenzene.

4.3  SLAG AND SOLID RESIDUALS LEACHABILITY

     A major objective of this SITE Demonstration  was to evaluate the TCP's ability to produce, from
hazardous waste feed, a  non-hazardous solid residual in which heavy metals  are bound  in an inert slag
that complies with the regulatory requirements of TCLP. Compliance with the California WET-STLC also
applied since the tests were conducted in  California.  The TCLP and WET-STLC results for the soil,
slurry,  and solid residual  products are presented  in Table 4-3.

4.3.7   Test Slurry  Leaching Characteristics

     The  test slurry was spiked with  lead nitrate and barium nitrate to create a surrogate  RCRA-
hazardous waste feed and to evaluate  the  TCP's ability to  produce  a non-hazardous solid  residual in
which heavy metals are bound in  an inert slag resulting in TCLP and WET-STLC  measurements that are
lower than their respective regulatory limits. Table  4-3 shows that the test slurry feed  measurements
were higher than the TCLP and WET-STLC  regulatory limits  for lead but lower than the regulatory limits
for barium.

     Prior to the preparation of  the slurry feed for the SITE Demonstration, the excavated Purity Oil
Sales  Superfund Site  soil  was  spiked with lead  nitrate  and  barium nitrate.  The spiked soil was
subjected  to  a  TCLP-response test to  ensure  that the contaminated soil exceeded TCLP regulatory
limits.  The TCLP measurement for a lead spike of 15,000  mg/kg was 223 mg/L in  the soil; the TCLP
                                               59

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                    Table 4-2.  Destruction and  Removal  Efficiencies (DREs) for
                 Principal Organic Hazardous Constituent  (POHC)  - Chlorobenzene
ORE for gasification process
Run
1
2
3
Average
WH*
(Ib/h)
6.20
6.30
6.75
6.42
Raw syngas
(Ib/h)
0.00016
0.00019
0.00023
0.00019
Flash gas
(Ib/h)
0.000013
0.000010
0.000014
0.000012
Total WOUT"
(Ib/h)
0.000173
0.000200
0.000244
0.000210
ORE***
(%)
99.9972
99.9966
99.9964
99.9967
ORE for overall Texaco MRL operation
Run
1
2
3
Average
ww'
(Ib/h)
6.20
6.30
6.75
6.42
Fuel gas
(Ib/h)
0.0000033
0.0000620
0.0000130
0.0000250
Abs. off gas
(Ib/h)
0.00010
0.00038
0.00023
0.00024
Oxid. offgas
(Ib/h)
< 0.000019
0.000018
0.000011
<0.000016
Total Vl^* .
(Ib/h)
<0.000122
0.000460
0.000254
<0.000281
ORE***
(%)
> 99. 9980
99.9926
99.9962
> 99. 9956
      Win = Mass feed rate of Chlorobenzene (POHC) in the waste stream feed.
      Wout = Mass emission rate of Chlorobenzene (POHC) in gas effluent streams
               Ww - WOUT
       ORE =	  X 100
result for  a barium spike of 30,000 mg/kg was 329 mg/L. At these  spike  concentrations, the Purity
Oil soil exceeded the TCLP regulatory limits  for lead  (5 mg/L) and barium (100 mg/L).

4.3.1.1  Normalized TCLP and WET-STLC Values for Lead in Test Slurry-.

     The  test soil composed of approximately 20 weight-percent Purity Oil soil (lead TCLP of Purity Oil
soil:  223 mg/L) and 80  weight-percent clean soil (lead  TCLP of clean soil:  <0.03  mg/L), could be
expected to have a normalized, or corrected, TCLP value for lead of  approximately 40 mg/L.  The test
slurry, composed of approximately  20 weight-percent total soil (normalized  TCLP value for lead: 40
mg/L) diluted by the remaining slurry solution of 80 weight-percent coal, gypsum, and water  (no  lead
TCLP value) could  be expected to  have a calculated TCLP  value for lead  of around 8 mg/L, which
closely approximates the average TCLP measurement of 8.3 mg/L lead for the test slurry. Similarly,
                                               60

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                                Table 4-3. TCLP and WET-STLC Results
                                             Lead  and Barium

Regulatory value
Purity Oil soil
Clean soil (S-1)** . .
Slurry (SL-1)*** . . .
Coarse slag (S-3)
Fine slag (S-4)
Clarifier solids (S-5)

Regulatory value
Purity Oil soil * .
Clean soil (S-1 )**
Slurry (SL-1)*** ) . . .
Coarse slag (S-3)
Fine slag (S-4)
Clarifier solids (S-5)
TCLP Pb
mg/L
Range****
Average
5.0
223
<0.03
8.1-8.4
3.3-5.8
11-18.3
691-1,330
8.3
4.5
14.9
953
TCLP Ba
mg/L
Range****
Average
100
329
0.3
0.1-0.2
0.5-0.8
1.2-2.0
1.2-3.8
0.1
0.6
1.75
2.7
WET-STLC Pb
mg/L
Range* ***
Average
5.0

<0.5
54-61
6.7-11.1
22.8-52.9
903-1,490
56
9.8
43.0
1,167
WET-STLC Ba
mg/L
Range****
Average
100
...
<6.0
<5.0-6.5
<6.0
5.6-10.4
14-51.4
<5.5
<6.0
9.3
38.4
      Lead TCLP of Purity Oil soil (waste feed to produce Purity oil slurry) with 15,000 mg/kg (as elemental lead) lead nitrate
      spike and barium TCLP of Purity Oil soil with 30.000 mglkg [as  elemental barium) barium nitrate spike-measured in pretest
      spike study.
      Clean soil is soil matrix used to produce clean soil slurry.
     *** The SITE Demonstration slurry (SL-1)  is a mixture of slurries produced using Purity Oil soil and clean soil. SL-1 is
      composed  of 26,800 Ib of Purity Oil slurry mixed with 138,040 Ib of clean soil slurry. (See Table 4-I.)
      Range of values for SL-1, S-3, and S-4 based on 4 samples and S-5 based on 3 samples.
 Pb: Lead
 Ba: Barium
an  expected normalized WET-STLC value of 280  mg/L lead, based on  spiked soil blending, would be
consistent with the  average WET-STLC  measurement  of 56  mg/L  lead for the test slurry, due to  the
dilution of the  coal,  gypsum, and water.
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4.3.1.2 Fate of Barium in  Test Slurry-

     The fate  of the barium contaminant  indicates  that significant changes occurred in  the  barium
chemistry during  slurry formulation.   A pretest study TCLP  value  of 329  mg/L was measured in a
leachate  produced from the spiked  Purity  Oil soil.  This contrasts with the much  lower  0.1  mg/L
measured in the TCLP leachate  from the test slurry  matrix, which included coal, gypsum, and water.
The introduction of sulfur-containing gypsum and coal could have provided an environment in the slurry
that changed the original soluble barium nitrate spike material to insoluble barium sulfate. The  relative
solubilities  of  barium nitrate and barium sulfate differ by ten-thousand fold. Since barium  sulfate is
relatively insoluble, it remains with the solids and  does  not transfer to the leachate during the TCLP
test.  The one  thousand times reduction in the test  slurry TCLP  result for  barium from the pretest level
in  the  Purity Oil soil  would be consistent with a  partial speciation change to  barium sulfate.

4.3.2  SITE Demonstration  Results

     The SITE Demonstration  showed that  the  leachability  of the lead in the main  residual solid
product-the  coarse  slag-was lower than the leachability of the lead in the contaminated/spiked soil.
The  leachability of the barium essentially remained  unchanged.  The  average TCLP  and WET-STLC
measurements for coarse  slag, which comprised 62.5 weight-percent of the total solid residuals, were
lower than the TCLP regulatory  levels for  lead and  barium  and  the WET-STLC regulatory  value  for
barium. The average TCLP and WET-STLC measurements for fine slag, which constituted 35.9  weight-
percent of the total  solid  residuals, and  clarifier solids,  which  amounted to 1.6  weight-percent,  were
higher than the TCLP and WET-STLC regulatory  limits for lead but lower than the tests' regulatory limit
for barium. The leach test results indicated mixed  success in meeting the test objectives. Analysis of
the effects of  dilution  by the  non-contributing slurry components-coal,  water, gypsum-on the TCLP
and WET-STLC test results showed that the  TCP  can potentially  produce-as  its major solid residual-a
coarse slag  product with  TCLP and  WET-STLC measurements below  regulatory  limits.  The TCP
effectively treated a  soil matrix exhibiting  a normalized TCLP  value  of 40 mg/L for  lead  and  produced
a coarse slag with an average TCLP value of 4.5 mg/L lead and  a fine slag with an average TCLP value
of 14.9 mg/L  lead.

     The average WET-STLC measurements for all solid residual streams were higher than  the WET-
STLC  regulatory values for lead. However,  the TCP demonstrated significant  improvement in reducing
lead mobility  as measured  by  WET-STLC results.  The process  treated  a soil  matrix exhibiting a
                                               62

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normalized WET-STLC value of 280 mg/L for lead and produced a caorse slag with an WET-STLC value
of 9.8 mg/L and a fine slag, with an  average WET-STLC of 43 mg/L lead.

4.4 SYNTHESIS  GAS PRODUCT

4.4.1  Synthesis  Gas Composition

     The  synthesis  gas (syngas)  product from the TCP is composed primarily  of  hydrogen, carbon
monoxide, and carbon dioxide. For a commercial unit, the raw syngas would receive further treatment
in an  acid gas treatment system to  remove hydrogen sulfide. This would produce a combustible  fuel
gas that could be burned  directly in a  gas turbine/electrical generation facility or be synthesized  into
other  chemicals.

     The  raw gas from  the gasifier was sampled and analyzed to evaluate the  TGP's ability to gasify
a slurry containing a RCRA-hazardous waste material and produce a synthesis gas  product. This gas
stream was then  treated in the Texaco MRL Acid :Gas Removal  System; the  resulting fuel gas product
was flared. Table 4-4 shows  the compositions'of the raw  syngas and the fuel gas  product.

4.4.2  Products of  Incomplete  Reaction (PIRs)

     The  TCP is a  gasification  process which converts  organic materials into syngas by  reacting the
feed with a limited amount of oxygen (partial  oxidation).  In addition to the syngas mixture  of hydrogen
and carbon monoxide, other organic  compounds  appear as  products of the incomplete partial oxidation
reaction. The term "PIR" describes the  organic compounds detected  in the gas  product streams as a
result  of the incomplete  reaction process.

     All gas streams, including the raw gas, flash gas from the gasification section, fuel gas, absorber
off-gas, and  oxidizer off-gas contained  trace  amounts of volatile and semivolatile  PIRs.  Carbon
disulfide,  benzene,  toluene,  naphthalene, naphthalene derivatives, and acenaphthene concentrations
were  measured in the gas streams at parts per billion  (ppb) levels. The POHC-chlorobenzene-was
also detected. Small amounts of methylene chloride and phthalates were also detected but likely were
                                              63

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                                                 Table 4-4.  Synthesis  Gas  Composition
Raw syngas composition an
Run
1
2
3
Average
ป2
(vol. %)
34.6
26.9
35.4
32.3
CO
{vol. %)
33.0
31.3
39.6
34.6
CO2
[vol. %)
25.9
26.9
26.2
26.3
CH4
(ppmv)
87
51
42
60
N2
(vol. %)
6.5
5.1
5.7
5.8
I heating value
Ar
(vol.%)
0.3
0.0
0.05
0.1
cos
(ppmv)
120
170
130
140
H2S
(ppmv)
1,180
3.050
1,980
2,070
THC
(ppmv)
49
17
14
27
Heating value
(Btu/dscf)
219
210
228
219
Fuel gas composition and heating value
Run
1
2
3
Average
H,
(vol. %)
37.6
38.3
34.7
36.9
C O
(vol. %)
39.1
35.0
41.3
38.5
C02
(vol. %)
21 .0
20.9
21.2
21.0
CH.
(ppmv)
71
49
44
55
N2
(vol. %)
5.8
4.9
5.6
6.4
Ar
(vol. %)
0.2
0.05
0.1
0.1
COS
(ppmv)
33
44
50
42
H,S
(ppmv)
490
580
68
380
THC
(ppmv)
32
16
15
21
Heating value
(Btu/dscf)
239
239
239
239
o>
      V\2'-  Hydrogen
      CO: Carbon monoxide
      CO2- Carbon dioxide
CH4:     Methane
N2:
Ar:
Nitrogen
Argon
COS:    Carbonyl sulfide
H2S:     Hydrogen sulfide
THC:    Total hydrocarbons (excluding methane)

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sampling  and analytical  contaminants.   Measured  concentrations  of  PCDDs and PCDFs in the gas
streams were comparable to the blanks,  indicating that these species, if present, were at concentrations
less than  or  equal  to the method detection limits (parts per quadrillion).  Other compounds,  such as
xylenes, chloromethane,  bromomethane, dibenzofuran, fluorene, and  phenanthrene (expected  from the
thermal treatment of coal and chlorobenzene), were detected at lower concentrations in the flash gas
and off-gases.

     During the SITE  Demonstration all of the  effluent gas streams including the fuel gas, and the
absorber and oxidizer off-gases, were routed to a flare.  For a commercial  design, the fuel gas product
will  be  further  processed for use  as a fuel  for  power generation  or an  intermediate for  chemical
synthesis. The  absorber  and oxidizer off-gas streams or their equivalent  effluents based  on the final
commercial design  will either be flared or  further  processed, treated,  or recycled,  based on permit
constraints.

4.4.3 Particulate  Emissions

     During the SITE Demonstration, particulate emissions were measured for the raw syngas and fuel
gas streams.  These averaged 6.1 milligrams per cubic meter (mg/m3) in  the raw syngas, and 1.3 mg/m3
in the  fuel gas.  By comparison, the particulate emission standards for  boilers and industrial  furnaces
processing hazardous waste  (40 CFR Part 266 Subpart H), and industrial,  commercial,  and institutional
steam  generators processing coal and other fuels (40 CFR Part 60 Subpart  Db) are higher than the
average measured  values for these gas streams.  Since the fuel gas product would  not be vented  or
flared in  a commercial unit, but would be burned  directly in a  gas-turbine/electrical-generation facility
or  synthesized  into other  chemicals, it  is  expected that  the  treated  vent  gas  from any  of these
downstream facilities will be treated  to meet applicable  particulate emissions standards. This must be
assessed  on a case-by-case basis.

4.4.4 Acid Gas  Removal

     Hydrogen chloride  gaseous emission rates  measured from 0.0046 to 0.0117 Ib/h. The chlorine
concentration in the feed slurry, based  on  a chlorobenzene spike addition equivalent  to 3,150 mg/kg
in the  slurry  and the chloride  concentration in the slurry,  ranged from 4.3 to 4.7 Ib/h. Using these
figures, the TCP's  hydrogen  chloride removal  efficiency exceeded 99 percent.
                                               65

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      Sulfur-containing gas emission rates measured from 2.2 to  2.7 Ib/h. The sulfur concentration in
the slurry,  based on  the  ultimate  analysis for  sulfur, ranged  from 0.97 to 1.20 weight-percent.  Using
these figures, the TGP's sulfur removal  efficiency averaged 90 percent.

      According  to Texaco,  the MRL systems  for acid gas removal  are designed to process a wide
variation (flow and  composition) of gas  streams based on the developmental-nature of the research
activities conducted there. It is expected that  systems designed to meet the  specific requirements of
proposed commercial TCP  units will  provide higher removal  efficiencies.

4.5 METALS PARTITIONING

      The fate of the  spike metals  in the slurry (lead and  barium) appeared to  depend on their relative
volatilities under TCP operating conditions.  Lead-a volatile  metal-concentrated in the clarifier solids,
which were scrubbed  from the raw syngas. Lead probably evaporated in the  hot regions  of the gasifier
and condensed  on the fine particles in the cooler areas of the process.  The  more  refractory barium did
not concentrate in  any particular  solid  residue.  It partitioned  throughout the solid residual  streams
roughly in proportion  to the mass  of each residual stream.

      As presented in Table 4-5, average lead  concentrations  were 880 mg/kg, 329  mg/kg, 491 mg/kg,
and 55,000 mg/kg in  the  Demonstration  slurry,  coarse slag, fine slag and clarifier solids, respectively.
Although the  clarifier  solids comprised only  1.6 weight-percent  of the  solid  residuals, they  contained
71.1 weight-percent of the measured  lead in all the  solid  residuals. The remaining 28.9 weight-percent
of the lead partitioned to the coarse and fine slags.

      Average barium concentrations were  2,700 mg/kg, 11,500  mg/kg, 15,300 mg/kg,  and 21,000
mg/kg in the Demonstration slurry, coarse slag, fine slag  and clarified solids, respectively. The barium
partitioned to the solid  residual streams in  approximate proportion to the mass flow of each  stream.
The coarse  slag, which comprised 62.5  weight-percent of the  solid residuals, contained 55  weight-
percent of the measured barium in the solid residuals. The remaining 45 weight-percent of the barium
partitioned to the fine slag and clarifier solids  in approximate proportion to their mass flow.
                                                66

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         Table 4-5. Mass Flow Rates and Total Concentrations of Lead and
                       Barium in Slurry Feed and Solid Residuals*

Flow rate (Ib/h)
Range** . .
Average
% of Residuals
Pb concentration (mg/kg)
Range ** .
Average
Pb mass rate
Average (Ib/h)
% of Slurry Pb
% of Residuals Pb
Ba concentration (mg/kg)
Range ** .
Average
Ba mass rate
Average (Ib/h)
% of Slurry Ba
% of Residuals Ba
Slurry
(SL-1)

2,212-2,291
2,216

867-899
880

2.00

1 ,750-3,580
2.700

6.1
Coarse slag
(S-3)

250-307
273
62.5

198-542
329

0.09
4.5
15.3

8,090- 16,300
11,500

3.1
50.8
55:0
Fine stag
(S-4)

151-167
157
35.9

217-651
491

0.08
4.0
13.6

11.800-18.300
15,300

2.4
39.3
42.5
Clarifier solids
(S-5)

3.1-10.5
6 . 8
1.6

43.400-72.000
55,000

0.42
21.0
71.1

15,100-26,300
21,000

0.14
2.3
2.5
     Mass flow rates of and metal concentrations for slurry are on as received basis; for solid residuals are on dry basis.
     Flow rate range  for  SL-1, S-3, and S-4 based on 3 measurements and S-5 based on 2 measurements. Pb and  Ba
     concentrations ranges for SL-1, S-3, and S-4 based on  4 samples and S-5 based on 3 samples.
 Pb:  Lead
 Ba: Barium
4.6 PROCESS WASTEWATER

     The Demonstration produced three process wastewater streams: process wastewater (flash tank
blowdown  and quench/scrubber and lockhopper water inventory on  shutdown);  gasification  vacuum
filtrate  (produced from the vacuum filtration  of the clarifier bottoms); and neutralized wastewater from
the sulfur removal unit. Samples from each  of these streams were collected and analyzed for  VOCs,
SVOCs, PCDD/PCDF,  metals, pH, and organic and  inorganic halogens.  Samples of the inlet water
stream were also analyzed to determine if it was  introducing any contaminants of concern.
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     Lead concentrations in the  process wastewater and vacuum filtrate  ranged from 12.4 to 38.9
mg/L and from 3.98 to 18.4 mg/L, respectively. Although the majority of the lead  was found  in the
clarifier solids, small amounts of lead  or lead compounds remained suspended in the clarifier overhead
and  traveled to the  process wastewater as the flash tank blowdown. Similarly, small amounts of lead
remained suspended in the vacuum filtrate and did not settle in  the clarifier solids.

     Trace  concentrations of  VOC  and  SVOC  PIRs such  as  benzene,  acetone,  carbon disulfide,
methylene chloride, naphthalene and naphthalene  derivatives, and fluorene were  found in the
wastewater streams.  No concentrations  of PCDDs or PCDFs  were found at  or above the method
detection limit of 10 nanograms per liter (ng/L).

     Inorganic chloride concentrations in  the wastewater streams  ranged from 380  mg/L to 6,800
mg/L. These values were, in general, an order of magnitude higher than the concentrations found in
the inlet  water; they indicated the presence  of additional chlorides in the  feed. Ammonia was also
detected  in the process wastewater and vacuum filtrate streams; the pH values  of these streams were
fairly neutral. The inorganic chloride concentrations indicated  the presence  of chloride,  but the neutral
pH values indicate that the chloride species is not acidic. These results  show that the  HCI produced
in the gasification  process was  removed in the quench and scrubber, neutralized  by the ammonia, and
discharged in  the process wastewater/vacuum filtrate effluents.

     Concentrations of organic chloride in  the inlet water ranging from  680 mg/kg (Run 3) to 2,500
mg/kg  (Pretest) were  carried through the  system to the wastewater streams.  Similar  concentrations
appeared  in the process  wastewater, vacuum filtrate,  and neutralized wastewater streams.

     For proposed  commercial units, the wastewater streams would  be  treated  on-site for recycle or
for disposal  as non-hazardous  water.
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                                        SECTION  5
                        OTHER  TECHNOLOGY  REQUIREMENTS

5.1  ENVIRONMENTAL REGULATION REQUIREMENTS

     Section 2 -  Technology Applications Analysis, Subsection 2.1  - Objectives - Performance versus
ARARs discusses specific environmental  regulations  pertinent to the  overall activities associated with
the  operation of the TCP.

     Permits  may be  required by state  regulatory agencies  prior to implementing the  TCP system.
Permits may also be required to operate the system  and to store wastes during and  after processing.

     If off-site treatment/disposal  of contaminated  residuals and wastewater is required,  they must be
taken off site  by  a licensed transporter to a permitted  landfill under manifest documentation.

5.2  PERSONNEL  ISSUES

     Overall labor requirements for the activities associated with the operation of the  TCP are discussed
in Section 3 -  Economic  Analysis.

     The excavation  and processing of hazardous waste-material requires the development of  site-
specific health and safety plans that address personnel responsibilities, chemical and  physical hazards,
PPE, site  control,  hazard-zone definition, decontamination  procedures,  exposure monitoring,
recordkeeping, and maintenance  of Up-to-date  specific material safety data sheets for all  site-related
chemicals of concern. All technicians involved in  excavation activities  or  operation  of the TCP  are
required to  have  completed  OSHA hazardous waste operations training and must  be familiar with all
relevant OSHA requirements. For most sites, minimum PPE for technicians will include  gloves,  hard
                                             69

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hats, steel toe  boots, and  coveralls. Depending on contaminant types and concentrations,  additional
PPE may be required; excavation activities may require particulate  protection with  a cartridge-equipped
respirator and specific TCP operations  mandate the need for chemical resistant/fire retardant coveralls.

5.3  COMMUNITY ACCEPTANCE

     Community acceptance  and other Superfund feasibility study  evaluation criteria are addressed in
the Executive Summary.  As  mentioned  above,  Subsection  2.1  - Objectives -  Performance versus
ARARs  also discusses specific environmental  regulations  criteria that impact on the acceptance of a
TCP unit within  a specific community  or  jurisdiction.

     Fugitive emissions can be  managed  by watering down the soils prior to excavation and handling
and covering stockpiled soil with plastic.

     The TCP's solids grinding and slurry  preparation system can include  negative pressure enclosures,
nitrogen  blanketing,  baghouse collection of particulates and carbon adsorption for organics removal to
control fugitive emissions  prior to the  slurrying of the coal and soil with  water.

     The TCP unit can also respond to community noise concerns  by the design and noise-dampening
of rotating equipment.
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                                        SECTION 6
                                 TECHNOLOGY STATUS

6.1 PETROLEUM PRODUCTION TANK BOTTOMS DEMONSTRATION

     A demonstration was conducted in 1988 at MRL for the California Department of Health Services
where petroleum tank  bottoms  from a California oil production field were  co-gasified with  low-sulfur,
western  coal. This California-designated hazardous waste was  fed to the gasifier at a rate of 600 Ib/h
mixed with 2,450 Ib/h of coal slurry. The  dry syngas  was  composed of 39 percent carbon  monoxide,
38  percent hydrogen,  and 21  percent carbon  dioxide.   Texaco  reported  that the solids were non-
hazardous, based on California Assessment Manual limits for total and leachable metals  in effect at the
time of the demonstration. Both the  solids and wastewater were free of trace organics and EPA priority
pollutants. Treatment results are presented in Appendix II.

6.2 EL  DORADO,  KANSAS REFINERY PROJECT

     Texaco  has announced plans to  build a  75-million  dollar TCP  power facility at  its El Dorado,
Kansas  refinery,  which will  convert about  170  tpd of non-commercial petroleum  coke,  hydrocarbon
streams, and  RCRA-listed hazardous wastes into syngas. The  syngas,  combined with natural gas, will
power a gas turbine to produce approximately 40 megawatts  of electrical  power-enough to meet the
full  needs of the  refinery. The exhaust heat from the  turbine will be used to produce 180,000 Ib/h of
steam-approximately 40  percent of the refinery's  requirements.  Construction  will  begin  during the
first quarter  of 1995, with start-up  projected for the  second  quarter of  1996.

     The U.S. EPA, Office  of  Solid Waste and  Emergency Response,  has reviewed the El  Dorado
project and has judged that the gasifier would be an exempt recycling  unit  as provided  under 40 CFR
261.6(c)(l)  and does  not meet the definition of an incinerator, a boiler,  or an industrial furnace.
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                                        APPENDIX I
                                    VENDOR CLAIMS

     Appendix 1 summarizes claims made by Texaco regarding the SITE Demonstration and the Texaco
Gasification Process (TGP). The information presented herein represents Texaco's point of view; its
inclusion  in this Appendix does not constitute U.S. Environmental Protection Agency approval or
endorsement.

/. 1 INTRODUCTION

     The TGP is a proven, commercial technology with  a reputation for flexibility, reliability, efficiency,
and environmental superiority. This reputation is based on more than 40 years of worldwide commercial
experience and is supported by nearly 50 years of continuous research and development.

     Texaco's participation in  the SITE Demonstration Program is part of a decade-long  effort to expand
the use of the technology to waste treatment. The Demonstration showed that the TGP can effectively
treat soils and sludges that are contaminated with hazardous organic pollutants while producing a
syngas with  commercial  value. The Demonstration also  showed that the process provides a means to
concentrate volatile heavy metals  into  a small  stream of solids,  potentially  suitable for  metal
reclamation.

     The  projected treatment costs are lower than other thermal treatment technologies. Also, the
nature of the process is  such that a single unit can treat soils with varying properties, including type,
degree of contamination, moisture content,  size distribution, and silica:clay  ratio.

     The  balance of this Appendix I provides additional information related to the results of the
Demonstration.  Appendix II  presents case study results  of other testing conducted by Texaco.
Together, Appendices I and II include information on:
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     •  Texaco's  gasification  testing  programs and  facilities;
     •  Independent data and test results gathered by Texaco during the Demonstration;
     •  Pilot-scale tests on other waste feeds conducted by Texaco  (Case Studies - Appendix II).

1.2.1 Texaco's Gasification Testing Programs  and Facilities

     The  SITE Demonstration was held at the Montebello Research Laboratory (MRL) where pilot units
are available to support Texaco's  research and  development efforts and to  provide the design and
permitting data required for commercial  projects. The reliability of MRL data for commercial design has
been validated  over nearly  50 years of experience.  Because of the relatively large scale of these units
(15-45 tpd  of coal equivalent),  they  are also used to demonstrate  and test commercial plant
configurations and components.

     The  scope of the test programs vary to meet  the objectives of each  project. Normally, such as
with  a  new  feedstock, pilot-unit tests  are preceeded by  laboratory tests to characterize the feed and
to determine appropriate operating  conditions. These tests are then followed by one or more pilot-unit
evaluations,  generally  of increasing length,  ranging  from  one-half day to confirm operability, to up to
7 days or as needed to gather environmental  data

1.2.2 Process Data Gathering  and Analysis

     MRL's  pilot development units  are  fully equipped  and instrumented to  gather detailed process
data. Operation of the  HPSGU II, the  Selexol Acid Gas  Removal Unit, and the  Sulfur Removal Unit,
used during  the Demonstration, are  controlled using a  modern  electronic  distributed control system.
On-line instruments are used to provide  continuous data on the flow rates, temperatures, and  pressures
of the  various process streams.   Gas  stream compositions  are  monitored  using  two  on-line mass
spectrometers.  Additional systems allow extensive sampling of the process streams for off-line testing.

     Most  of  the  analytical  testing is  done in the  fully-equipped,  on-site  analytical  laboratory.
Environmental sampling and  analyses are usually contracted to  independent  laboratories.

     Mass  and energy balances are  calculated by  statistically adjusting the raw data to achieve 100
percent closure for carbon,  hydrogen, oxygen, nitrogen and sulfur (major species). This is done with
the minimum overall change to the raw data while limiting the change in  any  one variable  to no more
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than the expected random variation in its  measurement  The adjusted data are used as the basis for
reporting  results.

1.2.3  Syngas  Composition

      Important characteristics of the TCP are the stability of the process during steady-state operations
and the smooth accommodation  to  variations in the  feed  rate and composition. Syngas composition
data  from  the Demonstration illustrate this  stability.  Averages  of data, recorded every 60 seconds
from the two on-line mass spectrometers during Runs 1-3,  are shown in  Table l-l; the data from each
run are in  excellent agreement,  with only  minimal variations in the syngas composition.  This reflects
the relatively  steady  operating conditions  during the Demonstration and  is  consistent  with  previous
pilot-unit and  commercial-plant experience.
                      Table 1-1. Svnaas Composition Data - On-Line Analvsis
Test Run
Run 1
Run 2
Run 3
Syngas composition, vol%
Hydrogen (H2)
Carbon Monoxide (CO)
Carbon Dioxide (CO,)
Methane (CHJ
Argon (Ar)
Nitrogen (N2)
Hydrogen Sulfide (H2S)
Carbonyl Sulfide (COS)
Total
34.05
35.05
27.05
0.00
0.15
2.98
0.90
0.01
100.19
34.27
36.17
25.54
0.01
0.15
3.11
0.90
0.01
100.16
34.14
36.18
25.81
0.00
0.15
2.96
0.91
0.00
100.15
1.2.4 Mass Balance  Data

      Unadjusted balances for carbon, hydrogen,  nitrogen, sulfur and oxygen were calculated from the
compositions and flow rates of each of the streams entering and leaving the gasification pilot unit. For
all three runs,  the  unadjusted  balances closed to within 99-101  percent for the five major species,
which  indicates  that the data were of very high  quality.
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     The overall mass balances for Runs 1-3 show that essentially all of the organic matter in the feed
was converted  to syngas. The unconverted carbon in the residuals  represented  less than 0.5 weight-
percent of the  carbon in the feed slurry, and unconverted carbon was well below 0.05 weight-percent
of the  total weight of the coarse and fine slag.

1.2.5 Metals Partitioning

     During  the  initial stage  of pilot-unit operations, there is  a tendency for  some residual solids to
accumulate in portions of the  gasification pilot  unit. These solids are generally the finer size materials
which also tend to be enriched in volatile metal species, such as lead. Recoveries of these species tend
to increase with time making  it difficult  to achieve  consistently high recoveries  of the  residual  solids
during  short  operating  periods.  Therefore,  efforts are made to recover the remaining  residual  solids
after each test. The results  obtained by  Texaco,  based on  their  post-demonstration  sampling,  are
presented in  Table 1-2.
                         Table 1-2. Mass Flow Rates of Lead and Barium in
                                   Slurry Feed, and Solid  Residuals

Dry solids
Avg. flow rate (Ib/h)
% of SL-1
Pb
Avg. flow rate (Ib/h)
% of SL-1
Ba
Avg. flow rate (Ib/h)
% of SL-1
Slurry
(SL-1)

443.9*


1.94


9.99

Coarse slag
(S-3)

273.1
61.5

0.524
27.0

3.34
33.5
Fine slag
(S-4)

128.6
29.0

0.405
20.0

1.77
17.7
Clarifier solids
(S-5)**

5.06
1.1

0.60
30.9

Total
recovery


91.6


78.8

0.076
0.8 | 52.0
      Mass flow rate based on  ash.
      Clarifier  solids samples  were taken over a 71  -hour period before and  during the 3  test runs.
      Slurry, coarse slag, and  fine slag samples were taken during the 35-hour period of the 3 test runs.
 Pb: Lead
 Ba: Barium
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 1.2.6 Dioxins and Furans

      It is known that dioxins and furans (PCDD/PCDF) are formed during the incineration of chlorinated
wastes and that they are perhaps not simply the products of incomplete combustion. However, in the
reducing atmosphere of a Texaco gasifier, these compounds cannot form and are, based on substantial
technical and operations data,  destroyed, if present. The data from the SITE Demonstration run show
that concentrations of PCDD/PCDF above the detection  limits of the analysis, in the  range of parts per
quadrillion  (actually less than  0.01  ng/m3),  could  not  be  reliably measured in the syngas. These
concentrations are significantly lower than those expected from  incineration.

  1.2.7 Slag Stability

      The  long-term stability of slag products from the TCP was tested indirectly in 1989 through 1992
by  a research  program at  the College of Agricultural Sciences,  Pennsylvania State University. Coal
gasification slag from the Cool  Water  Program was evaluated  as a hydroponic medium. An unpublished
report concluded that  chrysanthemums and poinsettias grown  in slag-amended media  had nutrient
contents in the normal  range.

1.3 COMMERCIAL DESIGN DIFFERENCES

1.3.1  Unit  Design

      The  HPSGU II pilot gasifier used for the Demonstration is part of a research facility and would not
 be  copied for a commercial plant. A commercial plant would not be designed to  handle the broad range
of feedstocks processed at  MRL, which have included liquefied auto tires and plastics, oily wastes, and
sewage sludge. A  commercial  unit  for soil  remediation would  be  designed for a lower  operating
 pressure,  have a larger lockhopper to  handle the increased  volume  of slag, and incorporate a more
efficient gas cleaning system.

1.3.2 Thermal Efficiency

      Most  operating gasifiers  are designed  to  maximize the  production of hydrogen  and carbon
 monoxide.  The TCP is capable of efficient gasification by consuming  a minimal part of the fuel value
 in the feed to maintain  the process operating temperature. The use of oxygen rather than air, the small
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reactor size with  low  heat losses,  and the entrained-bed design,  which allows low residence times, all
contribute to the improvement of  thermal efficiency.

      In the application  of TCP to soil remediation, operating at  a high thermal efficiency  may not be
as important as increasing the throughput of soil. Economics may justify using more of the available
heat to handle more slag-forming  solids.  Operation  with more oxygen provides  the extra heat  and
results in a  greater percentage of carbon  dioxide in the syngas.

 1.3.3 Uses of Syngas

     The valuable constituents of  syngas are hydrogen and  carbon monoxide when used as chemical
feedstocks or  used as fuels. Any equipment necessary to further  process the syngas was not included
in the economic analysis presented in Section 3. The syngas can  be  combusted directly in a boiler or
an engine  driving an electric generator,  in which  case combustion  of the  syngas  will oxidize trace
compounds  and further  reduce their concentrations in the exhaust gases. If the plant is located near
a refinery  or  chemical  plant, the  syngas may be  reformed via further processing to increase the
hydrogen  or methane content.

1.3.4  Alternative Auxiliary Fuels

     The Demonstration was  carried out  using  coal as an auxiliary fuel to  supplement the fuel value
of the soil. Any higher-Btu source  could have been considered as an auxiliary fuel,  including waste oil
or another high-Btu waste. Two auxiliary fuels that are considered suitable for contaminated soils are
oil and petroleum coke.
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                                       APPENDIX II
                                      CASE  STUDIES

     The results of three previous demonstrations of gasification of wastes  at the MRL are presented
for  comparison.  No organic compound  heavier  than methane  was  found  in the  raw syngas at a
concentration above 1 ppmv during any run. The volatile metals were concentrated in the clarifier solids
and in some cases resulted in classifying this small solids stream as a RCRA hazardous waste.

11.1 PETROLEUM PRODUCTION TANK BOTTOMS

     In  December, 1988, a 25-hour gasification run was made in the Low Pressure Solids Gasification
Pilot Unit with a mixture of 20 weight-percent field tank bottoms from  the Richfield  East Dome Unit of
the  Los Angeles basin  and 80 weight-percent SUFCo  Utah  coal as part of a study for the California
Department of Health Services (Contract 88-T0339). The purpose  of the test was to demonstrate  the
gasification  of a RCRA-exempt,  low-Btu hazardous waste.

     The tank bottoms  had a higher heating value of 5,500  Btu/lb, a moisture content of 64.6  weight-
percent, and were contaminated with 3,000  mg/kg of benzene, toluene, ethylbenzene, and xylene. The
combined slurry  feed rate was 2,976 Ib/h with a solids concentration of 62 weight-percent.

     The gasification process successfully and  effectively converted the hazardous material to a useful
syngas product and non-hazardous effluents.

II. 2   MUNICIPAL  SEWAGE SLUDGE

     Thirty-four tons of dried sewage sludge produced at Newark, NJ from raw, dewatered sludge, and
4,000 gallons of condensate  from the indirect  dryers were shipped  to MRL  for  a series  of nine
gasification  runs in December, 1990. The dried sludge was remixed with condensate  and  ground with
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3 parts Pittsburgh #8 coal to 1 part sludge and fed to the HPSGU II in a 53 weight-percent solids slurry.
The  slurry  feed rate was  2,150  Ib/h.

     As in the SITE Demonstration, volatile heavy metals tended to partition to the clarifier solids. Lead
was  present in the feed slurry at a  concentration  of 188  mg/kg and 85.7 weight-percent of the
recovered lead was found in  the clarifier solids. This stream, representing just 3 weight-percent of the
total  solids, exceeded the TCLP limits for lead and cadmium. The coarse slag and fine slag streams did
not exceed the test limits for any metal.

11.3  HYDROCARBON-CONTAMINATED  SOIL

     The  disposal  of  a hydrocarbon-contaminated  soil by gasification with coal was demonstrated
during  a  54-hour  run in March, 1991.  The  HPSGU II pilot unit was  used  to gasify  a mixture of 86
weight-percent of Pittsburgh #8 coal and 14 weight-percent topsoil contaminated  with 4 weight-percent
heavy vacuum gas  oil  from Texaco's Los Angeles  refinery. A total of 3.8  m3 of topsoil and heavy gas
oil was gasified.  The  gasifier feed rate was  2,150 Ib/h  of slurry  with a solids concentration of 65
weight-percent.

     The  purpose of the  test was to show that the addition of a small amount  of contaminated soil
would have minimum impact  on the operation of the coal gasifier.  Extensive environmental data were
gathered  during  this  test  and  demonstrated  the feasibility of gasifying a contaminated  soil  while
producing  a useful syngas.

     The coarse and fine slag were non-hazardous under Federal and California standards. The clarifier
solids were above  only the California  WET-STLC  regulatory limits for arsenic and lead.  The clarifier
solids stream  is  minor and  tends  to  concentrate the metals  in  the  feed.  In this case the volume
reduction of hazardous solids was  94  percent.

     Typical syngas data from the  three case studies  described above are  summarized  in Table 11-1.
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Table 11-1.  Raw Syngas Composition and Heating Value
Case Study
Waste
feed
11.1
Tank
bottoms
1 1. 2
Sewage
sludge
II.3
Soil
Svnaas composition, vol.%
Hydrogen (H2)
Carbon monoxide (CO)
Carbon dioxide (CO,)
Nitrogen (N2)
Argon (Ar)
Methane (CH4), ppmv
37.68
39.45
21.21
1.32
0.08
300
35.0
38.5
23.5
1.9
0.1

34.5'2
48.36
15.64
0.18
0.08
420
High heating value, Btu/dscf ,

317
314
321
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