United States
Environmental Protection
Agency
.
Hazardous Waste Engineering Research *
Laboratory '/t
Cincinnati OH 45268 '
Research and Development
EPA/600/S2-85/049 June 1985
Project Summary
Innovative Thermal Hazardous
Waste Treatment Processes
Harry Freeman
The full report contains discussions
of 21 thermal processes identified by
the U.S. Environmental Protection
Agency (EPA) as innovative processes
for treating or destroying hazardous
organic wastes. The subject processes
were identified through two national
solicitations for innovative processes
and several extensive literature surveys.
Information about the subject pro-
cesses was provided voluntarily by the
process developers. The criteria used
for selection of a process for the report
included the innovativeness of the pro-
cess when compared with conventional
existing processes and the potential
contribution the process could make to
the evolving field of hazardous waste
management technology.
This Project Summary was developed
by EPA's Hazardous Waste Engineering
Research Laboratory, Cincinnati. OH,
to announce key findings of the research
project that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).
Background
The full report contains discussion of
21 thermal processes identified by the
U.S. Environmental Protection Agency
(EPA) as innovative processes for treating
or destroying hazardous organic wastes.
The subject processes were chosen
through two national solicitations for
innovative processes and several exten-
sive literature surveys. The project also
produced much of the information for the
alternative technologies section of a 1984
EPA report on issues related to ocean
incineration.
While the processes included in the full
report differ widely in many respects (i.e.,
waste streams for which they are de-
signed and state of development), they
are similar in that they offer innovative
approaches to solving problems present-
ed by the generation of hazardous wastes.
The reader is cautioned to understand
that, while some of these processes have
been evaluated by third parties, inde-
pendent testing of these processes, espe-
cially tests under the guidance of the
EPA, are the exception rather than the
rule. However, all of the processes are
considered at least promising. Some of
the included processes might be regarded
as emerging technologies. Others are in
commercial operation and are already
well beyond any such categorization as
emerging technology.
Information provided in the full report is
intended to assist in the evaluation of the
processes by researchers and others
interested in alternative processes for
treating and disposing of hazardous
wastes. Theinclusionofa process shou Id
in no way be considered an endorsement
of the process by the EPA. The reader is
encouraged to contact the organizations
for more information.
No project such as this one can include
all innovative processes. A process not
being included should not be interpreted
as a negative evaluation of that process. It
is the Agency's intention to publish other
compilations such as this one periodi-
cally. Those individuals wishing to have
their process included should contact the
Alternative Technologies Division, Haz-
ardous Waste Engineering Research Lab-
oratory.
Asummary of the included processes is
contained in Table 1. A compilation of
expressed advantages and potential lim-
itations for the subject processes is
shown in Table 2.
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Table 1, Process Summary
Process Name
Description
State of Test Data Cost Data
Waste Streams Development Available Available
Contact
Wet Oxidation
Processes:
Zimpro
Wet Air Oxidation
IT
Catalyzed Wet
Oxidation
MODAFt
Supercritical Fluid
Oxidation
Methods Engineering
High Temperature Wet
Oxidation
Chemical Transporta-
tion Processes:
Battelle Northwest
Aqueous Phase Alka-
line Destruction of
Halogenated Organics
CARD
Catalytic Dehalo-
genation of Hazardous
Wastes
Battelle Northwest
Joule Heated Glass
Melter
Uses elevated tempera-
ture and pressure to
oxidize organics in water
Uses selected catalysts
and elevated temperature
and pressure to oxidize
organics
Uses high temperatures
and very high pressure to
oxidize organic
contaminants in water
Uses long vertical under-
ground tubular reactor to
oxidize suspended
organfcs in water
Converts halogenated
organics into an oil using
mild alkali under pressure
Aqueous streams with
less than 5% organics
Aqueous waste stream
with suspended
organics
Aqueous slurries or
organic solutions
Liquids or sludges
Dehalogenizes com-
pounds by replacing
halogen atom with
hydrogen atom
Applies electric current
directly to waste material
for combustion and for
creation of a glass matrix
Co
NA
Halogenated liquids
and granular solids
NA
Liquids with high con-
centration of halogen
compounds
Soils and other
granular mineral
matter
NA
NA
William Copa
Zimpro, Inc.
Military Road
Rothchild, Wl 54474
(715)359-7211
IT Enviroscience. Inc.
9041 Executive Park Drive
Knoxville, TN 37923
(615)690-3211
MODAR, Inc.
14 Tech Circle
Natick, MA 01760
(617)655-7741
Methods Engineering, Inc.
P. 0. Box 282
Angleton, TX 77515
(713)331-7268
Battelle
Pacific Northwest
Laboratories
P. 0. Box 999
Rich/and. WA 99352
(509) 375-2927
Chamberlain National
GARD Division
7501 N. Natchez Avenue
Mies, IL 60648
(312)647-9000
Battelle
Pacific Northwest
L aboratories ~
P. 0. Box 999
Rich/and, WA 99352
(509) 375-2927
Molten Glass Process:
Penberthy
Electromelt Pyro
Converter
Fluidized Bed
Incineration:
Battelle Columbus
Multisolid Fluidized
Bed
Uses a bed of molten
glass to oxidize organics
and to capture ash
and inroganics
Uses a moving bed of
heated inert material to
incinerate wastes
Any liquid or solid
waste stream
NA
Granular solids,
sludges, slurries.
liquid and gases
NA
NA
Penberthy Electromelt
International, Inc.
631 South 96th Street
Seattle. WA 98108
(206) 762-4244
Battelle Memorial
Institute
505 King A venue
Columbus, OH 43201
Attention: Jack Conner
GA Technologies
Circulating Bed Waste
Incineration
Waste-Tech Services
Low Temperature Fluid
Bed
Uses a circulating mass
of heated inert material
to incinerate waste
materials
Solids, sludges, and
liquids
A.B
Uses granular combust/on Liquids, sludges,
catalyst and limestone in slurries, or soils
a fluid bed
William Rickman
GA Technologies
P. 0. Box 85608
San Diego, CA 92138
(619)455-3860
Waste- Tech Services, Inc.
P. O. Box 736
Idaho Falls, ID 83402
(208) 522-0850
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Table 1. (continued)
Process Name
Description
State of Test Data Cost Data
Waste Streams Development Available Available
Contact
Pyrolysis Processes:
Midland Ross
Pyrolytic
Decomposition
Heats waste materials in
the absence of oxygen to
drive off volatiles for
incineration or recovery
Viscous liquids,
sludges, and high ash
materials
ft/A Midland-Ross Corporation
Energy Technology
Division
900 N. Westwood
P. O. Box 985
Toledo, OH 43696
(419)537-6444
Russell andAxon
High Temperature
Pyrolysis with Oxygen
Uses oxygen induced high Solids and liquids
temperature to pyrolyze
water
NA
Russell and Axon
319 N. Fourth Street
Suite 700
St. Louis, MO
63102-2774
(314)231-9693
Molten Salt:
Rockwell International
Molten Salt
Destruction
Uses a bed of mo/ten
sodium carbonate to
destroy wastes and scrub
acid gases
Low ash. low water
content, solid or
liquid wastes
NA Rockwell International
Environmental and Energy
Systems Division
8900 De Soto Avenue
Canoga Park, CA 91304
(213)700-8200
Advanced Incinerators:
Industronics
Consertherm Rotary
Kiln
A modular controlled air
incinerator
Liquids, sludges, or
solids
Industronics, Inc.
489 Sullivan Avenue
P. 0. Box G
South Windsor, CT
06074-0956
(203)289-1551
PEDCo Technology
Fast Rotary Reactor
A rapidly rotating cylinder Solids or sludges
utilizing dryer technology
for waste incineration
NA PEDCo Technology
Corporation
11499 Chester Road
Cincinnati, OH
45246-1000
IGT
"Cyclin" Cyclone
Incinerator
Electric Reactors:
Thagard
High Temperature
Fluid Wall Reactor
Huber
A dvanced Electric
Reactor
Plasma Systems:
Pyrolysis Systems
Pyroplasma
A cylindrical shaped
combustion chamber
provides for intensive
mixing of fuel and air
Uses electrically
induced radiant heat to
pyrolyze organic
contaminants
Uses electrical heat to
pyrolyze organic materials
at extremely high
temperatures
Uses plasma arc device to
create extremely high
temperatures for waste
destruction
Gases or atomized
liquids
Granular solids
Finely ground solids
Highly toxic liquids
Institute of Gas
Technology
3424 South State Street
Chicago. IL 60616
(312)567-3650
Thagard Research
Corporation
3303 Harbor Boulevard
Suite F-4
Costa Mesa, CA 92626
J. M. Huber Construction
P. O. Box 2831
Borger, TX 79007
(806)274-6331
Pyrolysis Systems, Inc.
4935 Kent Street
Niagara Falls, Ontario
L2H 1J6
Contact: Mr. Ian Thorn
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Table 1. (continued!
Process Name
Description
State of Test Data Cost Data
Waste Streams Development A variable Available
Contact
Applied Energetics
Plasma Temperature
Incinerator
Burns waste in a
pressurized stream of
preheated oxygen
Liquids and fluidized
solid waste
Applied Energetics, Inc.
P. O. Box J177
Tullahoma, TN 37388
(615)455-0631
Contact:
Dr. John B. Dicks
State of Development
C - Commercially available
C* - Commercially available for other than hazardous wastes
P - Pilot scale
B - Lab and bench scale
Co - Conceptual
Test Data Available
A - Sponsored by EPA or other third party
B - Company sponsored tests
C - Company sponsored pilot-scale tests
D - Company sponsored bench-scale tests
NA - Not Available
Cost Data Available
/ - Based on commercial scale operation
2 - Estimates based on pilot-scale operation
3 - Estimates based on bench-scale operation
NA - Not Available
Table 2. Summary Comments on Processes
Process
Expressed A dv ant ages
Potential Limitations
Zimpro Wet Air Oxidation
IT Catalyzed Wet Air Oxidation
MODAR Supercritical Fluid Oxidation
Methods Engineering High Temperature Wet Oxidation 1.
2.
3.
Battelle Northwest Aqueous Phase Alkaline Destruction
of Halogenated Organics
1. Thermally self-sustaining at 1.
relatively low organic
concentrations 2.
2. Attractive option for dilute toxic
waste streams
3. Products of oxidation stay in
liquid phase
1. Catalysts lower oxidation 1.
temperatures
2. Catalysts increase the rate of 2.
reaction
3 More refractory compounds
may be oxidized 3.
1. Rapid oxidation rates and 1.
very short residence times
2. Complete oxidation of 2.
organic eliminating need for
off gas processing
3. Very efficient removal of
inorganic constituents
Pressures are contained by J.
standard tubing 2.
Mild steel can be used
Process accommodates a wide 3.
range of concentrations and
flow rates
1. Energy recovery in converted 1.
oil
2. Reducing conditions minimize 2.
ox/dative formation of
dioxin 3.
3. Based on standard industrial
technology
Generally limited to aqueous stream
containing nonhalogenated contaminants
Not appropriate for so/ids and very viscous
liquids
Addition of catalysts increases costs of
process
Process best used on a select type of waste,
i.e., moderate strength aqueous wastes having
high toxicity
Process is yet to be demonstrated at pilot
scale
High pressures necessitate sophisticated
equipment and operational techniques
A continuously operating unit has yet to be
demonstrated
The process is still in the conceptual stage
Corrosion and fouling of equipment may
reduce capacities
Permitting of an underground reactor could
present problems
Relatively low temperatures may not be
sufficient for halogenated wastes
Potential suitable waste materials may
not be many
Interim and supplementary products of the
reaction could be more hazardous than
original waste stream
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Table 2. (continued)
Process
Expressed A dvantages
Potential Limitations
CARD Catalytic Dehalogenation of Hazardous Wastes
Battelle Northwest Joule Heated Glass Melter
Penberthy Electromelt Pyro Converter
Battelle Columbus Multisolid Fluid/zed Bed
GA Technologies Circulating Bed Waste Incineration
Waste-Tech Services Low Temperature Fluid Bed
Mid/and Floss Pyrolytic Decomposition
Russell and Axon High Temperature Pyrolysis with
Oxygen
Rockwell International Molten Salt Destruction
Industronics Consertherm Rotary Kiln Oxidizer
PEDCo Technology Fast Rotary Reactor
IGT "Cyc/in" Cyclone Incinerator
Thagard High Temperature Fluid Wall
2.
3.
1.
2.
1.
2.
3.
2.
3.
1.
2.
3.
2.
3.
Process retains economic
value of materials while
rendering them harmless
Mild operating conditions.
uncomplicated equipment
Easily transportable equipment
Excellent residuals
incorporation into glass matrix
High retention of heavy metals
Significant volume reductions
Residual product is fully
stable glass
Based on existing glassmaking
technology
Safe and economical disposal 1.
of waste materials
Energy recovery 2.
Minimum fuel preparation
Low temperature eliminates 1.
ash agglomerization and NO*
emissions
Complete combustion to
minimize organic emissions
Minimal downstream emissions
control required
Can effectively handle 1.
contaminated soil
2.
Salts and metals are not 1.
liquified or vaporized
Reduced paniculate emissions 2.
Process tends to tie up
teachable metals and salt
in residue
Process has not been demonstrated beyond a
bench scale
1. Electrical energy source may be costly
2. Secondary combustion of off gas may be
required
1. Does not appear appropriate for soils
and high ash material
2. Off gas treatment will probably be
required
3. Technology is unfamiliar to hazardous
waste treatment industry
1. Temperature excursions may deteriorate
the bed
2. May not be suitable for solids incineration
1. Ultra high temperatures
2. Long residence time
3. No fugitive emissions
1. Process destroys waste
materials without NO*
emissions
2. Halogens are retained in the
salt bed.
1. Rugged dependable
construction
2. Capability of cofeeding liquids,
sludges, and solids
3. High turndown ratios
1. Reliability and dependability
2. High thermal efficiency
3. Handles wide variety in feed
rate
1. Stable and energy efficient
combustion
2. Small combustion volume
3. Low temperature combustion
1. Reduced residence times
2. Complete destruction of waste
materials by virtue of high
temperatures
3. Production of medium-Btu
combustible gas
Low temperature may limit the process to
less refractory waste streams
Effectiveness may be reduced through catalyst
removal
Extended demonstration is needed
The process appears best suited to a
relatively homogeneous waste stream
interim possible hazardous byproducts should
be assessed
1. Use of oxygen increases the cost substantially
2. Generally requires cocombustion with a solid
material
1. Process is limited to low ash, low water
content waste
2. Molten salt can be very corrosive
Extended demonstration with hazardous
wastes is needed
Extended demonstration with hazardous
wastes is needed
Extended demonstration with hazardous
wastes is needed
1. Input solids must be ground extremely finely
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Table 2. (continued)
Process
Expressed A dvantages
Potential Limitations
Huber A dvanced Electric Reactor
Pyrolysis Systems Pyroplasma
Applied Energetics Plasma Temperature Incineration
1. Process is very transportable
2. Extremely high treatment
efficiencies
3. Essentially no stack or fugitive
emissions
1 Process can handle highly 1
toxic and refractory 2.
compounds
2 Scale of equipment is small
3. ON/OFF time cycle of only
a few minutes
1. Process is contained in a very 1
compact unit 2
2. Combustion reaction increases
under these conditions
Input solids must be ground extremely finely
Limited to liquids
Demonstration of continued operation is
needed
Limited primarily to liquids
Demonstration of continuous operation is
needed
As the United States continues to sup-
port the conversion of hazardous waste
processes from those based on land dis-
posal to those based on alternative tech-
nologies, the processes such as the one
reviewed in the full report will become
more common. This encouraging tech-
nology development should further the
day when hazardous waste management
and disposal is not a problem.
Summary
The processes can be placed into the
following generic categories:
Wet Oxidation—processes for oxidizing
suspended and dissolved organics in
aqueous waste streams that are too di-
lute to incinerate economically, yet too
toxic to treat biologically. By confining the
oxidation to the aqueous medium, wet
oxidation does not produce the type or
quantity of emissions produced by typical
incinerators. The wet oxidation process
using the feature of supercritical water is
especially innovative in that effective
separation of inorganics from the waste
stream can be realized in addition to
complete oxidation of organics. Wet oxi-
dation does not work as well on chlor-
inated organics as on many nonchlor-
inated organics. However, wet oxidation
has been used in experimental work to
break down chlorinated materials into
less hazardous compounds. In general, it
is a very promising alternative technology
for a common hazardous waste stream,
i.e., aqueous wastes containing nonchlor-
inated toxic organics.
Chemical Transformation—processes
that transform the waste streams into
other less toxic substances primarily
through chemical reactions. These pro-
cesses are important in that they are
examples of technology to encourage
resource recovery rather than destruc-
tion of wastes. As treatment processes
become more the norm than landfills or
even than incineration, chemical trans-
formation processes will occupy a much
larger segment of the waste manage-
ment picture. This is especially true for
those chemical processes that produce
useful materials. Currently, these pro-
cesses have difficulty competing with
conventional disposal methods. However,
as disposal costs rise, chemical processes
such as the ones discussed in the full
report will become increasingly attractive.
Molten Glass—processes that use a
pool of molten glass as the heat transfer
mechanism to destroy organics. The
attractiveness of molten glass is based
upon the extremely good quality of the
residue from the process, i.e., essentially
nonleachable glass. The combustion con-
ditions for organics appear to be at least
as good as those present in hazardous
waste incinerators, and the inorganic
residue and ash is incorpordted into the
glass. Introduction of this type of technol-
ogy into the waste management industry,
especially for highly toxic organic streams
containing toxic metals, could prove very
attractive if it can be shown through
extraction tests that the residue is non-
leachable and may be delisted as a
hazardous waste.
Fluidized Bed lncinerat/on—lberma\
processes using a very turbulent bed of
inert granular material to improve the
transfer of heat to the waste streams to
be incinerated. Advantages of fluidized
bed incinerators include their relatively
compact design, their relative simplicity
of operation, and their ability for combin-
ing combustion with pollution control by
trapping some gases in the bed. Although
fluidized beds have been used for many
years in various industries, their use in
hazardous waste incineration is still at a
demonstration level. It is generally agreed,
however, that this approach to waste
incineration offers significant potential
for the future.
Pyrolysis—processes that break down
waste materials into less complex mate-
rials through the application of heat in the
absence of oxygen. Pyroconversion units
are typically custom designed to process
specific types of chemicals rather than as
multipurpose waste processing units.
Consequently, their use as multipurpose
hazardous waste treatment facilities has
been very limited. However, one of the
pyrolysis processes discussed in the full
report would be suitable for use as a multi-
purpose waste processing unit. Advan-
tages of pyrolysis processes are that there
is a potential for byproduct recovery, that
sludge volumes may be reduced without
large amounts of supplementary fuel
being used, and that air emissions are
usually less for conventional incinerators.
Molten Salt—a process in which waste
material is injected beneath a bed of
molten sodium carbonate for incinera-
tion. The process is innovative in that the
use of the molten bed requires lower
temperatures for waste combustion. Also,
the bed acts as a very effective scrubbing
medium for acid gases.
Advanced Incinerators—processes that
incorporate improvements over conven-
tional incinerators but which maintain
the essential principles of conventional
incinerators. The full report contains
three such systems—a liquid injection
system incorporating fuel feed to promote
extremely intensive mixing and two sys-
tems using rotary kilns. These systems
illustrate the improvements being made
in conventional incinerator designs.
Electric Reactor—processes that pyro-
lyze waste contaminants from particles
-------
such as soil through use of an electrically
heated fluid wall reactor. These units
have been used successfully in other
chemical processes and are just begin-
ning to be adopted for waste destruction.
The units, especially the portable ver-
sions of the processes, appear to offer a
very different and potentially valuable
thermal option for hazardous waste treat-
ment.
Plasma Systems—processes that use
the extremely high temperature of plasma
to destroy waste materials. The plasma
systems offer a very innovative approach
to destroying highly toxic chemicals. Sev-
eral systems have been researched. Two
of these systems are discussed in the full
report.
The EPA author Harry Freeman is with the Hazardous Waste Engineering
Research Laboratory, Cincinnati, OH 45268.
The complete report, entitled "Innovative Thermal Hazardous Waste Treatment
Processes,"(Order No. PB 85-192 847/AS; Cost: $14.50, subject to change)
will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA author can be contacted at:
Hazardous Waste Engineering Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
Mention of trade names or commercial products does
not constitute endorsement or recommendation for
use by the U.S. Environmental Protection Agency.
U. S. GOVERNMENT PRINTING OFFICE: 1985/559-111/20609
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Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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