&EPA
United States
Environmental Protection
Agency
Air And Radiation
(6601J)
EPA 402-R-97-009
July 1997
Descriptive Data On Muffle
Furnaces Used At Savannah
River, Rocky Flats And Hanford
For DOE's Pu Disposition
Program
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Compilation of Descriptive Data on Muffle Furnaces
Used at Savannah River, Rocky Flats, and Hanford
for DOE's Plutonium Disposition Program:
Interview Summary Report
Prepared for:
U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
Radiation Protection Division
Center for Remediation Technology and Tools
September 1997
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DISCLAIMER
Although this document has been published by the U.S. Environmental Protection Agency, it
does not make any warranty, express or implied, or assumes any legal liability or responsibility
for the accuracy, completeness, or usefulness of any information, apparatus, product, or process
disclosed in this document. Reference herein to any specific commercial products, process, or
service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its
endorsement or recommendation for use. The views and opinions expressed herein do not
necessarily state or reflect those of the EPA and shall not be used for advertising or product
endorsement purposes.
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PREFACE
A goal of the U.S. Environmental Protection Agency's Office of Radiation and Indoor Air,
Center for Remediation Technology and Tools (EPA/ORIA/RTTC) is to bring innovative
remediation technologies for radioactive and hazardous mixed waste to the Office of Air and
Radiation. This involves investigating any techniques that show promise in meeting EPA site
cleanup goals for hazardous waste in soil and groundwater. Muffle furnaces are a type of electric
radiant oven that use refractory material to transfer heat from the heating element to the furnace
contents. Scientific research indicates that muffle furnace technology may be effective in
assisting with stabilizing and immobilizing excess plutonium and could be used as a component
of DOE's strategy to address excess plutonium. This paper describes muffle furnaces and how
they are being used at three Department of Energy facilities (Savannah River, Hanford, and
Rocky Flats) in relation to the plutonium disposition program. It is intended to be used by
anyone interested in learning about muffle furnaces and how they are currently used in the field
by environmental management and scientists responsible for identifying and selecting a-
remediation tool for use at sites containing radioactive materials.
This project is coordinated by the EPA/Office of Radiation and Indoor Air (EPA/ORIA). The
principal authors are from A.T. Kearney, Inc. EPA/ORIA acknowledges all reviewers (James C.
Marra from the Westinghouse Savannah River Company, Gregg Nishimoto from the DOE
Rocky Flats Environmental Technology Site, David W. Templeton from the DOE Hanford Site,
Ed Feltcorn from EPA/ORIA, and Irma McKnight from EPA/ORJA) for their valuable
observations and comments.
Questions and comments on this report can be addressed to:
Robin Anderson, Project Manager
EPA/Office of Radiation and Indoor Air
401 M Street, SW (6603J)
Washington, DC 20460
(202) 233-9385
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TABLE OF CONTENTS
DISCLAIMER i
PREFACE ii
TABLE OF CONTENTS iii
EXECUTIVE SUMMARY 1
1.0 INTRODUCTION 2
2.0 DESCRIPTION OF MUFFLE FURNACES 4
3.0 DOE SAVANNAH RIVER SITE - PLUTONIUM DISPOSITION PROGRAM ... 7
3.1 Studies Performed Using Muffle Furnace Treatment Technologies 8"
3.2 Effectiveness of Muffle Furnace Treatment Technology 9
3.3 Costs Associated with Muffle Furnace Treatment 9
3.4 Regulatory Requirements and Standard Practices 9-
3.5 Off-Gas Effluent Treatment 10
3.6 Additional Information 10
4.0 DOE HANFORD SITE - PLUTONIUM DISPOSITION PROGRAM 12
4.1 Studies Performed Using Muffle Furnace Treatment Technology 13
4.2 Effectiveness of Muffle Furnace Treatment Technology 13
4.3 Costs Associated with Muffle Furnace Treatment 14
4.4 Regulatory Requirements and Standard Practices 14
4.5 Off-Gas Effluent Treatment 14
4.6 Additional Information 15
5.0 DOE ROCKY FLATS SITE - PLUTONIUM DISPOSITION PROGRAM .:.... 17
5.1 Studies Performed Using Muffle Furnace Treatment Technology 17
5.2 Effectiveness of Muffle Furnace Treatment Technology 18
5.3 Costs Associated with Muffle Furnace Treatment 18
5.4 Regulatory Requirements and Standard Practices 18
5.5 Off-Gas Effluent Treatment 19
5.6 Additional Information 19
6.0 CONCLUSIONS 21
in
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TABLE OF CONTENTS (continued)
7.0 REFERENCE SOURCES 22
7.1 References - Savannah River Site Plutonium Disposition Program 22
7.2 References - Hanford Site Plutonium Disposition Program 24
7.3 References - Rocky Flats Plutonium Disposition Program 25
7.4 Other References 26
FIGURES
Figure 1. Bench-Top Muffle Furnace (Example) . 6
IV
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EXECUTIVE SUMMARY
The cleanup of Federal sites contaminated with radioactive residues, coupled with the excess
plutonium from dismantling of nuclear weapons will generate large quantities of radioactive
residues requiring long-term safe plutonium disposition. Scientific research indicates that muffle
furnace technology may be effective in assisting with stabilizing and immobilizing excess
plutonium. This report defines and describes how muffle furnaces operate and what role (if any)
they will play in the Department of Energy (DOE) plutonium disposition program. Three DOE
facilities have been selected to facilitate this discussion: (1) Savannah River Site, (2) Rocky Flats
Site, and (3) Hanford Site. This report presents a compilation of information gathered during
interviews with DOE representatives at these three DOE sites.
The muffle furnaces in use for DOE plutonium treatment research are a type of bench-top electric
radiant oven that uses refractory material to transfer heat from the heating element to the furnace
contents. Muffle furnaces are typically small; thus, they are used extensively in laboratory
research and can be incorporated into glovebox lines used for the handling of highly radioactive
materials.
Muffle furnaces have been used at Lawrence Livermore National Laboratory as part of the
ceramics immobilization research that is being conducted parallel to the work at Savannah River.
Research at Savannah River is currently being summarized in a major report that will be used by
DOE to decide between vitrification and ceramics immobilization of plutonium materials. It is
anticipated that the treatment method decision at Savannah River will affect other DOE sites
where disposition of excess plutonium must be addressed.
Muffle furnaces at the Hanford Site have been used to stabilize certain plutonium-bearing
residues at the Plutonium Finishing Plant and will continue to be used for this purpose.
Residues are being stabilized only so that they may be stored at Hanford more safely, pending
DOE decisions regarding the final disposition and disposal of excess plutonium. Research on
other plutonium disposition methods is not currently being performed at the Hanford Site. The
final determination of what treatment system will be used at Hanford is to be decided by DOE,
based on research at the Savannah River Site and the Lawrence Livermore National Laboratory.
Muffle furnaces will likely be used at Rocky Flats Environmental Technology Site (RFETS) for
the vitrification treatment of incinerator ash and related materials (sand, slag, crucibles, and
graphite fines). High- and low-temperature vitrification research studies using muffle furnaces
are currently being conducted at Los Alamos National Laboratory on behalf of RFETS. The
final design of the vitrification treatment system has not been determined for RFETS, since
research is still in its early stages.
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Compilation of Descriptive Data on Muffle Furnaces
Used at Savannah River, Rocky Flats, and Hanford
for DOE's Plutonium Disposition Program:
Interview Summary Report
1.0 INTRODUCTION
A goal of the U.S. Environmental Protection Agency, Office of Radiation and Indoor Air, Center
for Remediation Technology and Tools (USEPA/ORIA/RTTC) is to bring attention to innovative
remediation technologies for radioactive and hazardous mixed wastes to the Office of Radiation
and Indoor Air. By virtue of Reorganization Plan No. 3 of 1970, EPA is empowered to protect
the environment from the hazards of radioactive waste. Therefore, EPA is interested in
technologies that could be used to treat radioactive and hazardous mixed wastes in a manner that
prevents and/or minimizes the risk of contamination of the environment. EPA's interest includes
investigating techniques that show promise in meeting EPA site cleanup goals.
This report defines and describes how muffle furnaces operate and what role (if any) they will
play in the Department of Energy (DOE) plutonium disposition program. Three DOE facilities
have been selected to facilitate this discussion: (1) Savannah River Site, (2) Rocky Flats
Environmental Technology Site, and (3) Hanford Site. This report presents a compilation of
information gathered during interviews with DOE representatives: James C. Marra (Savannah
River Site), Leonard Gray (Lawrence Livermore National Laboratory), Gregg Nishimoto (Rocky
Flats Environmental Technology Site), Glen Chronister (Hanford Site), and W.S, Lewis
(Hanford Site). Most of the available muffle furnace information fell under the following
categories: studies performed, effectiveness, cost, regulatory requirements and standard practices,
and off-gas effluent treatment.
A muffle furnace is a type of electric radiant oven that uses refractory material to transfer heat
from the heating element to the furnace contents. Muffle furnaces are typically small. Thus,
they are used extensively in laboratory research and can be incorporated into glovebox lines used
for the handling of highly radioactive materials. Scientific research indicates that muffle furnace
technology may be effective in assisting with stabilizing and immobilizing excess plutonium and
could be used as a component of DOE's strategy to address excess plutonium.
Due to the end of the cold war, the United States now possesses approximately 50 tons of excess
plutonium, much of it weapons grade. Out of concern for public and environmental safety and to
safeguard against nuclear proliferation, DOE has committed to dispose of the excess plutonium.
The cleanup of contaminated DOE sites will also generate large quantities of radioactive residues
requiring long-term safe plutonium disposition. Disposition is defined as a process of use or
disposal of materials that results in the remaining material being converted to a form that is
substantially and inherently more resistant to use in nuclear weapons proliferation than the
original form. In other words, treatment for plutonium disposition is intended to create a
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condition in which the plutonium is roughly as difficult to acquire, process, and use in nuclear
weapons as it would be to use plutonium in commercial spent fuel for this purpose.
The excess plutonium exists in a number of forms, ranging from pure metal to plutonium
chemical solutions; thus, no one stabilization or immobilization option will be adequate to meet
the long-term plutonium disposition goals of DOE. At least apart of the plutonium will be
formed into mixed oxide (MOX) fuel pellets and used for fuel in commercial nuclear reactors.
This allows for the recovery of a large amount of usable energy. The remainder of the excess
plutonium will be stabilized (if required) and then immobilized in a matrix for ultimate delivery
to a geologic repository. The final immobilized form has to be stable over a geologic time frame,
be environmentally benign, and be at least as difficult to recover as plutonium from
commercially available spent nuclear fuel.
The options for disposition have been evaluated and the results published in a programmatic
environmental impact statement published by the DOE's Office of Fissile Materials Disposition
in December 1996. In that document, the DOE stated their preferred alternative for disposition is
a dual approach using both MOX fuels in nuclear reactors and immobilizing the remaining
plutonium through vitrification in borosilicate glass or by immobilization in ceramic, both using
can-in-canister techniques. DOE is scheduled to make a decision between glass vitrification or
ceramic immobilization on or near October 1,1997. Whichever technology is selected for final
disposition treatment, it appears that muffle furnaces may play a role either in the front-end
stabilization of plutonium-bearing residues prior to treatment or as a component of the
immobilization process for certain types of plutonium-bearing residues.
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2.0 DESCRIPTION OF MUFFLE FURNACES
The muffle furnaces that have been used in connection with DOE's plutonium disposition
research programs are a type of small electric radiant oven. The furnaces are characterized as
having heating elements that are either embedded in ceramic refractory material or ceramic
cement, or the heating elements may be separated from the internal furnace chamber by silicon
carbide plates or refractory firebrick. Refractory firebrick is the most durable material, since it is
capable of supporting heavy loads in the muffle furnace (e.g., loads up to 230 kilograms [500
pounds]). The units are insulated on all sides with ceramic fiber insulation or refractory
firebrick. The type of bench-top muffle furnaces that are being used for research at DOE's
facilities open on one side, with a door that may swing up, down, left, or right, depending on the
manufacturer and furnace design. A photograph and schematic of a typical muffle furnace with a
downward opening door is provided as Figure 1.
Muffle furnaces are typically small bench-top units, which are commercially available from
laboratory equipment supply companies. They come in a range of sizes and operating
temperature ranges. The smallest commercially available units have inner furnace chamber
volumes of approximately 1.3 liters (0.04 cubic feet). The larger commercially available units
have inner furnace chamber volumes of approximately 250 liters (9 cubic feet). Overall outer
dimensions also vary with the size and manufacturer of the furnace. For example, a small 1.3
liter inner volume unit has outer dimensions of 20.3 centimeters (cm) wide x 31 cm high x 22 cm
deep (8 inches x 12.5 inches x 8.5 inches). A larger 250 liter inner volume unit has outer
dimensions, for example, of 107 cm wide x 155 cm high x 126 cm deep (42 inches x 61 inches x
50 inches). Muffle furnace operating temperatures also vary with the type of refractory
insulation material, configuration of heating elements, and size of unit. The muffle furnaces
operate in temperature ranges of approximately 100°C to 1500°C (approximately 212°F to
2700°F). The temperature is set by the user. Current prices for muffle furnaces run from
approximately $700 for the smallest units to approximately $14,000 for the largest units.
Muffle furnaces may be used for a variety of industrial and laboratory applications including:
heat treating metal parts, heat treating ceramics or tiles, annealing glass, brazing, ashing of
organic and inorganic samples, ignition testing, gravimetric analysis, sintering, and drying and
firing x)f coatings.1 Because they are available in small sizes, muffle furnaces are ideally suited
for bench-top laboratory research and can be incorporated into glovebox lines used for the
handling of highly radioactive materials. The units are typically equipped with a chimney or
ventilation port to remove moisture, corrosive vapors, and smoke from the inner chamber. Some
models may be equipped with ports to inject inert gases or create special atmospheres in the
heated furnace chamber.
1 Annealing refers to the process of heating and cooling a material to soften and make it
less brittle. Brazing refers to soldering with a nonferrous alloy that melts at a lower temperature
that that of the metals being joined. Sintering refers to a process where a material is heated so
that it becomes a homogenous mass without actually melting.
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It should also be noted that other types of muffle furnaces exist. These include large and small
scale tunnel-type furnaces that are largely used for heat treating materials. While the small
bench-top tunnel muffle furnaces are typically electrically heated, the larger tunnel muffle
furnaces may be gas, oil, or electrically heated. The tunnel lengths may vary in size from a few
inches to several feet, depending on their design and use. The tunnel portion of the furnace is
lined with refractory material and the furnace is typically equipped with a conveyor belt or
similar mechanism to carry material through. Because tunnel-type muffle furnaces are not in use
at the DOE facilities of interest, this particular style of muffle furnace is not discussed further in
this report.
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-w-
Source: Photograph and drawing taken from catalog available on-line at hnD:/Vvv\v\v.bamsieadthermolvnc.c
Figure 1. Bench-Top Muffle Furnace (Example)
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3.0 DOE SAVANNAH RIVER SITE - PLUTONIUM DISPOSITION PROGRAM
One of DOE's preferred plutonium disposition options is the immobilization of piutonium, either
as vitrification in borosilicate glass or immobilization in ceramic material. Experiments on
vitrified glass have been conducted at the Savannah River Site. Parallel research involving
ceramic immobilization have been directed by Lawrence Livermore National Laboratory. While
muffle furnaces are not used in vitrification treatment, they are used in the ceramics
immobilization treatment process. There are currently two methods of ceramic immobilization
under consideration, hot pressing and cold pressing. Hot pressing in bellows would use muffle
furnaces for annealing after pressing, and the cold pressing method would use muffle furnaces
for the sintering stage that follows the cold press. The immobilization method that DOE will
use, either (1) vitrification, (2) ceramic hot press, or (3) ceramic cold press has not been decided
at this time, but DOE's decision is expected on or near October 1, 1997. A description of the
vitrification process follows, while a description of the ceramic immobilization process, which
uses muffle furnaces, appears in Section 3.1.
A main focus of DOE's plutonium disposition program has been to use the Defense Waste
Processing Facility (DWPF) at the Savannah River Site and a new High Level Waste (HLW)
vitrification facility to be built at the Hanford Site. The DWPF is operational and currently
vitrifying HLW remaining from weapons production activities at the Savannah River Site. This
waste is immobilized in borosilicate glass in large, 3 meters tall by 0.5 meter outer diameter (9.8
feet tall by 1.6 feet outer diameter), stainless steel canisters. Each canister holds approximately
1680 kilograms (3700 pounds) of vitrified glass. The canisters are stored at Savannah River
pending shipment to a permanent geologic repository. The Hanford vitrification facility will
likely be of similar design and purpose. It is not expected that muffle furnaces will be used in the
final design of the vitrification facility.
The inclusion of plutonium into the vitrification process for HLW presents many difficulties,
including worker radiation exposure, infrastructure costs, criticality issues, and safeguards and
security issues. Therefore, to deter access to plutonium, a focus has been on installing a series of
cans containing vitrified glass or ceramic immobilized plutonium into a canister of HLW (can-in-
canister method). A cold (non-radioactive) demonstration of this procedure was conducted at the
DWPF in December 1995, In the proposed vitrification process, the cans will be mounted on a
frame which will then be placed inside an empty DWPF canister. The canister would then be
filled with HLW glass in the same manner as other canisters. The canister will then be stored at
Savannah River until a permanent repository is ready. Once the facilities are operational, the
entire project should take approximately 10 years to complete. The can-in-canister method
would allow the DWPF to continue its primary mission of HLW vitrification, but also would
allow for the disposition of excess plutonium without major expenditures for modifying the
DWPF or delaying the DWPF primary mission. The can-in-canister method also allows the use
of HLW to form a radiation barrier to plutonium recovery. The radiation barrier is designed to
prevent theft and to make reprocessing the plutonium into weapons grade material more difficult.
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In any event, however, DOE's potential selection of vitrification as the preferred treatment
method for excess plutonium will not likely incorporate the use of muffle furnaces.2
3.1 Studies Performed Using Muffle Furnace Treatment Technologies
Ceramics immobilization does incorporate muffle furnaces as part of the treatment process.
There are two different ceramic methods being considered for immobilization, a hot press
method or a cold press method. Muffle furnaces would be used for the sintering step in the cold
press method and for annealing in the hot press method.
The ceramic being considered for plutonium immobilization is a synthetic rock material (Synroc)
composed primarily of pyrochlore, zirconolite, persovskite, hollandite and rutile, the exact
composition of which is yet to be determined.3 Zirconolite and pyrochlore have natural analogs
that have immobilized actinides over a geologic time frame. The first stage in preparation for
ceramic immobilization is to prepare a uniform feed material. This will require that the various
plutonium forms (pits4, metal, reactor fuel, oxides, etc.) be processed into a stable form, which
likely will be plutonium dioxide in a dry, powder form of reasonably uniform size and
consistency. The resulting materials are blended to provide a uniform feed material. Muffle
furnaces could possibly be used for the plutonium oxidation step. The use of a chemical
technique to oxidize plutonium is also being considered. The plutonium feed material is mixed
with ceramic precursors and neutron absorbers (for criticality control).
In the cold press method, the feed mixture is calcined into a dry powder in a rotary calciner to
remove any moisture, then formed and pressed for 5 minutes at 30 tons pressure. After pressing,
any pellet that appears to have been damaged or cracked is recycled into the feed process after
being crushed and milled. The pellets are then sintered at 1350°C (2460°F) for several hours
and allowed to cool. The pellets will then be loaded into cans and placed in short-term storage.
The cans will ultimately be loaded into a framework that is secured inside an empty DWPF
2 Information in this report on activities related to vitrification studies is based on
interviews with Mr. James C. Marra, Westinghouse Savannah River Company. Information on
the use of muffle furnaces in the ceramics immobilization studies was provided by Mr. Leonard
Gray, Lawrence Livermore National Laboratory.
3 Pyrochlore is a naturally occuring mineral that is comprized of different formulations of
the elements calcium, sodium, and niobium in an oxide, hydroxide, or fluoride form, with the
general formula of (Ca, Na)2Nb206(OH,F); Zirconolite is another rare earth oxide containing
calcium, zirconium, and titanium with the formula CaZrTi07; Persovskite is an oxide containing
calcium and titanium with the formula CaTi03; Hollandite is an oxide containing barium,
aluminum, and titanium with the formula BaAl2Ti606; and Rutile is a titanium oxide with the
formula Ti02.
4 "Pits" are weapons components containing plutonium.
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canister, which will then be filled with HLW. The filled canister is then welded shut, and placed
in storage until a permanent geologic disposal facility is available.
The other ceramics immobilization option is to use a hot press technique. The ceramic precursor
and plutonium feed are placed into a bellows and the lid is welded shut. The bellows is heated to
1200°C (2190°F) and pressed at 2000 pounds per square inch (psi) for 45 minutes.- The bellows
device is then placed into a muffle furnace for annealing, which would take up to 12 hours. The
Australian Nuclear Science and Technology Organization (ANSTO) Synroc Demonstration Plant
in Lucas Heights, Australia, has successfully demonstrated'the production of Synroc on a
commercial scale utilizing the hot press technique.
3.2 Effectiveness of Muffle Furnace Treatment Technology
The leachability of the ceramic forms is a significant benefit of the ceramics immobilization
treatment methodology, which use muffle furnaces in the treatment train. It measures the ability
of the treated material matrix to retain the plutonium constituents. The leaching rate of treated
material varies with different elements, but ranges from 1 x 10"5 to 1 x 10"8 grams/meterVday
(g/m2/day) in deionized water. Leachability rates for Synroc are very low. Synroc C leach rates
are less than 1 x 10'5 g/m2/day for uranium, while those of Synroc D are less than 8 x 10"3
g/m2/day for uranium.5 The plutonium leach rate is approximately 1 x 10'6 g/mVday. This is
important because plutonium-239 (?39Pu) has a half-life of 24,065 years, but decays to uranium-
235 C235!!), which is fissile and has a half-life of 700 million years. In addition, zirconolite can
immobilize approximately 10 percent of its weight in plutonium and pyrochlore can immobilize
up to 30 percent. Ceramics also resist the stress caused by formation of daughter products, have
high resistance to impact and thermal stress, and if broken tend to form large pieces with few fine
particles.
3.3 Costs Associated with Muffle Furnace Treatment
The estimated cost for the ceramic can-ih-canister alternative conducted at Savannah River
(which could use muffle furnaces) is approximately 1.8 billion dollars for plutonium processing,
immobilization, and disposal in a repository (including up-front equipment costs and final
facility decommissioning costs). This amount is identical to that estimated for the borosilicate
glass can-in-canister alternative.
3.4 Regulatory Requirements and Standard Practices
Shipping of plutonium materials from one DOE site to another for treatment, storage and/or
disposal will require consideration of the Department of Transportation (DOT) shipping
5 Synroc C refers to ceramic material that contains simulated, high-level Commercial
waste. Synroc D refers to ceramic material that contains simulated, high-level Defense waste.
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requirements of 49 CFR Parts 170 through 189, the Nuclear Regulatory Commission (NRC) in
10 CFR 71, and specific DOE standards. NRC transportation requirements for Type B quantities
of fissile materials incorporate DOT requirements by reference. A quantity of weapons grade
plutonium in excess of approximately 25 milligrams constitutes a Type B quantity per 10 CFR
71. Intrasite transportation is defined in DOE Order 460.1. Transportation to the
conversion/immobilization facility would occur in 6M/2R or equivalent packages for non-pit
plutonium, in Model FL or AT-400A for plutonium pits, and in NRC certified packages for
[unirradiated fuel in a safe secure trailer/transport.6 Transportation from the
conversion/immobilization facility to the repository would occur with the immobilized
plutonium contained in the DWPF canister, which will in turn be transported in a rail cask which
is currently under development.
Final disposal of treated plutonium materials will require consideration of all appropriate DOE
orders for nuclear waste disposal. All options under consideration will require that treated waste
material meet the waste acceptance criteria requirements of a waste repository, when one is
established.
3.5 Off-Gas Effluent Treatment
Off-gases generated during either type of ceramic immobilization treatment option, both of
which may use muffle furnaces as part of the treatment train, will be vented to an off-gas
condenser tank. The emissions will be scrubbed in a steam atomized scrubber and cooled by a
chilled water condenser. Gases from the condenser will then pass through a high-efficiency mist
eliminator and a set of high efficiency paniculate air (HEP A) filters before exiting the stack.
3.6 Additional Information
Muffle furnaces may be used as a component of the ceramics immobilization treatment of excess
plutonium. Information collected on the physical transformation of material following ceramics
immobilization treatment included data on density, residue loading, and durability. Density
provides information on how well the residue components have been incorporated into the
treatment material matrix, and, in the case of ceramics immobilization, how well the treatment
system compression techniques were performed. Loading refers to how much of the plutonium-
bearing residues may be incorporated into a single treatment event/unit (e.g., what percentage
residue is present in a treatment batch). Durability is a measure of the length of time that a
treated material can be expected to maintain its essential integrity. The information collected on
these issues includes:
• The ceramics hot press technique may produce a product that is greater than 98
percent of the maximum theoretical density. The ceramics cold press and
6 Packages including 6M/2R, Model FL, and AT-400A are types of containers that are
approved by NRC for the shipment of radioactive materials under 10 CFR 71.
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sintering technique may produce a product that is between 90 percent to 95
percent of the maximum theoretical density. The maximum theoretical density
depends on the feed materials used in the ceramics treatment method.
Assumptions used in the development of the ceramics can-in-canister variant
assume that the plutonium loading in the final ceramic form will be less than or
equal to 12 percent by weight. Laboratory scale samples have been made with
greater than 30 percent plutonium by weight, and engineering-scale samples have
been made with greater than 10 percent plutonium by weight.
The long-term durability of the treated residue form is a challenging aspect of the
research on plutonium disposition technologies. Material scientists must design
materials to performance standards measured not in decades, but in spans of
10,000 to 1,000,000 years, particularly in the case of long lived 239Pu isotopes.
Synroc has demonstrated excellent durability when mixed with actinides. A
major problem for many materials is that plutonium decays by alpha emissions,
forming fissile daughter products (23SU). This tends to cause swelling and micro-
cracking of the material. Synroc has shown resistance to both micro-cracking and
swelling. Long-term durability is confirmed from natural occurrences of similar
material that occur in diverse geological environments over geological time.
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4.0 DOE HANFORD SITE - PLUTONIUM DISPOSITION PROGRAM
Since production of plutonium was suspended in 1989, a significant amount of plutonium and
plutonium-bearing residues and solutions have remained in production facilities that have yet to
be decontaminated. One such facility is the Plutonium Finishing Plant (PFP) located at the DOE
Hanford Site. The PFP was put into production in 1949 and operated until 1989. The original
mission of PFP involved producing plutonium metal for use in nuclear weapons. As the demand
for plutonium oxide for reactor fuels increased, the mission of PFP changed to the production of
plutonium dioxide. Plutonium dioxide is a fine powder and was produced in large quantities for
both reactor fuels and research. In the 1960s, the Plutonium Reclamation Facility (PRF) was
built and PFP began receiving scrap material from military and reactor operations. The
plutonium was then removed from the scrap and converted to a usable form. This greatly
increased the types and forms of plutonium stored at the PFP. The PFP houses large amounts of
plutonium from other DOE sites that have been relocated for storage. The current plutonium
inventory includes more than 8000 categroized items. These categories are (1) plutonium-
bearing solutions; (2) oxides, fluorides and process residues; (3) metals and alloys; and (4)
polycubes and combustibles.7
Muffle furnaces have been tested for use in stabilizing plutonium and plutonium-bearing residues
at the PFP. The studies were conducted to determine if plutonium could be successfully
converted into plutonium dioxide, with the associated removal of all moisture and small
quantities (<2 percent) of organics in the treatment process. Treated plutonium is stored in
stainless steel cans in vaults at PFP, until the permanent method for immobilization is chosen and
final disposition occurs.
Pacific Northwest National Laboratories, also located at the Hanford Site, compared the various
methods for stabilizing plutonium located within the PFP. The DOE, in a final environmental
impact statement for PFP, selected ion exchange followed by vertical calcination and thermal
stabilization .as the preferred method for stabilizing chloride and nitrate plutonium-bearing
solutions. Muffle furnaces could be used for the thermal stabilization step of the process. The
solutions initially undergo ion exchange treatment. The ion exchange columns are operated in a
cyclical mode to reuse the resins. The vertical calciner is used to heat the solution to between
800°C to 1050°C (approximately 1470°F to 1920°F). The solution is fed into the calciner at 1
to 4 liters (0.26 to 1 gallons) per hour. The water in the solution is evaporated, nitric acid is
converted to nitrogen oxide gases and the plutonium undergoes oxidation to plutonium dioxide.
If the plutonium oxide powder is not stable enough after recovery from the calciner (i.e., is not
sufficiently oxidized), then it is further treated by thermal stabilization in a muffle furnace. A
sample of the plutonium oxide is then sent to an analytical laboratory to ensure that it meets DOE
7 Polycubes are polystyrene blocks containing plutonium oxides powder and coated with
aluminum and/or organic paint or tape. Combustibles consist of paper, rags, chemical wipes,
graphite, wood, and plastics.
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storage standards. If the material doesn't meet the storage standards, .then it will be re-stabilized
in the muffle furnace and re-analyzed. The plutonium dioxide powder will then be placed in
stainless steel cans and stored in vaults at PFP until a decision is made on final disposition.8
4.1 Studies Performed Using Muffle Furnace Treatment Technology
Studies were conducted at the PFP to determine if muffle furnace oxidation of plutonium-bearing
sludges via a glove box train was practical. The two 4000 watt muffle furnaces used for the
experiments were housed within the HC-21C glovebox at the PFP. The muffle furnaces were
Thermolyne Model FA1630 with chamber dimensions of 13 cm high x 14 cm wide x 33 cm deep
(5 inches x 5.5 inches x 13 inches) and operating ranges of 150°C to 1093°C (approximately
300°F to 2000°F). The feed material to be stabilized was sludge material remaining from the
last production run of the plutonium reclamation facility (PRF); and PRF training and floor
sweepings, which consist primarily of plutonium oxalate that had transformed to plutonium
oxycarbonate and plutonium oxide. The sludge was treated in batches of 500 grams (1.1
pounds). A metal container called a boat was weighed and then filled with the sludge and again
weighed prior to placement in the furnace. The furnace was heated slowly to 180°C
(approximately 350°F) to drive off combustible materials, then raised to a higher temperature,
950°C to 1050°F (approximately 1740°F to 1920°F), and heated until the material oxidized
(approximately 2 hours). Due to the potential presence of tributyl phosphate, which when heated
generates flammable butene gas, feed materials cannot exceed 2 percent organic materials. If
flammable off-gases were anticipated, the initial heating was done in an inert atmosphere (carbon
dioxide or another inert gas). Stabilized plutonium dioxide is being stored in PFP vaults until a
decision is made on final disposition.
A number of studies were conducted in support of these experiments, including a preliminary
hazard analysis initially conducted on an older thermal stabilization system that was very similar
to the HC-21C system described above. The study covered the glovebox system, supporting
services and activities for conditions that could threaten worker safety. Other studies included an
environmental assessment, experiments to select a suitable boat material, experiments on by-
passing the heat exchanger and an engineering study of the material conveyor system.
4.2 Effectiveness of Muffle Furnace Treatment Technology
The experiments conducted by the PFP demonstrated that muffle furnace treatment is effective
for the stabilization treatment of certain categories of excess plutonium. The single analytical
8 Information on activities related to muffle furnaces used in stabilization studies is based
on information provided by Mr. Glen Chronister and Mr. W.S. Lewis, Plutonium Finishing
Plant, Hanford Site.
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measure of successful stabilization was loss/gain on ignition.9 If the material contains too many
organic components, a loss of weight may be seen after stabilization due to decomposition and/or
evaporation in the treatment system off-gases. This weight loss was determined by weighing the
plutonium-bearing material placed in a boat before and after treatment. If the loss is greater than
1 percent, the material is re-stabilized. Gain on ignition may occur as oxidation occurs and
oxygen molecules combine with the plutonium. This could lead to a vacuum within the can or
expanded materials bulging the can.
4.3 Costs Associated with Muffle Furnace Treatment
Hanford Site PFP personnel10 generally indicated that the HC-21C system generates little waste
and requires a small number of operating personnel in comparison to other treatment
technologies.
4.4 Regulatory Requirements and Standard Practices
The PFP stabilized materials will be placed in storage vaults at the PFP, which were designed for
that purpose. The final treatment/disposition of these materials has not been decided, including a
decision on their leaving the PFP. DOE-standard DOE-STD-3013-96, Criteria for Preparing
and Packaging Plutonium Metals and Oxides for Long-Term Storage, outlines requirements for
the storage of stabilized plutonium oxides. This standard limits per package storage quantities to
5.00 kilograms of thermally stabilized plutonium oxides:
4.5 Off-Gas Effluent Treatment
The materials considered for stabilization during PFP experiments were sludge, plutonium oxide,
and plutonium oxalate. These materials were converted to plutonium dioxide,.and any organic
materials and water present in the plutonium materials were either thermally decomposed or
evaporated. The off-gases consisted of butene (if tributyl phosphate is present), nitrogen oxides,
carbon dioxide, and water. Air emissions from the HC-21C system pass through two HEPA
filters, eaqh stage of which removes 99.95 percent of particulate matter of 0.3 micron or larger
particles. It is not anticipated that the HC-21C emissions would detectably increase the PFP's
radiological output. For each batch of plutonium sludge material stabilized (500 grams), it is
estimated that 9 grams of butene, 90 grams of nitrogen oxides, 230 grams of carbon dioxide and
230 grams of water are released to the atmosphere.
9 Loss-on-ignition refers to the mass loss measured when a representative sample-of
thermally stabilized plutonium-bearing residue is heated to confirm the elimination of moisture
and other volatile constituents from the thermally stabilized material.
10 Information was provided by Mr. Glen Chronister and Mr. W.S. Lewis of the Hanford
Site Plutonium Finishing Plant.
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4.6 Additional Information
The final environmental impact statement for the PFP identified the preferred alternative and
secondary alternative methods for the stabilization of various materials containing plutdnium at
the Hanford Site. For the preferred alternative, muffle furnaces were only identified for use in
the stabilization of plutonium-bearing solutions. Information on the use of muffle furnaces as
part of the treatment train for the plutonium-bearing solutions was described in Section 4.0 of
this report. The secondary alternatives considered for the PFP included the potential use of
muffle furnaces for the treatment of three other categories of plutonium residues including: (1)
oxides, fluorides, and process residues; (2) metals and alloys; and (3) polycubes and
combustibles. These secondary alternatives are briefly described below:
• Plutonium oxides, fluorides, and process residues (which consist of ash, slag, and
crucibles, and other miscellaneous residues from equipment calibration) could be
thermally stabilized in a batch process using muffle furnaces. Under this
alternative, the residues would be fed into the muffle furnace and heated to a
temperature of approximately 1000°C (1830°F) for a minimum of one hour. The
high temperature air environment lowers the moisture level-and facilitates
conversion of incompletely oxidized plutonium to plutonium oxides.
• Plutonium metals and alloys could be thermally treated in a batch process using
muffle furnaces. Under this alternative, the residues would be placed into the
muffle furnace and heated to a temperature of approximately 1000°C (1830°F)
for a minimum of one hour. The high temperature air environment of the muffle
furnace facilitates conversion of the metal and alloy to plutonium oxides. It is
anticipated that a second thermal processing cycle would be necessary to oxidize
the material sufficiently to meet DOE storage standards. It would also be
necessary to pump air continuously through the muffle furnace during treatment
in order to maximize oxidation of the metals and alloys.
• Polycubes and combustibles containing plutonium residues could also be
thermally treated in a batch process using-muffle furnaces. Under this alternative,
the residues would be fed into a muffle furnace and heated to a temperature of
approximately 300°C (570°F). Initially the furnace would be purged with
nitrogen gas to maintain an inert environment and to prevent combustion of any
organic constituents in the residues. This would cause off-gassing of the organics,
which would be subsequently burned in a secondary combustion chamber that
would be part of the off-gas treatment process. The plutonium-bearing material
remaining in the muffle furnace would be heated to 1000°C (approximately
1830°F) for a minimum of one hour to convert the plutonium to plutonium
oxides.
Although none of these methods using muffle furnaces were identified as the preferred treatment
alternative for plutonium-bearing materials at the PFP, they were identified as viable secondary
alternatives. The possibility exists that these three additional waste categories could be treated
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using muffle furnaces in the future. The current preferred alternatives for the oxides, fluorides
and process residues category is thermal treatment in a continuous-feed furnace; for metals and
alloys management activities involve repackaging without further treatment; and for polycubes
and combustibles the preferred treatment is pyrolysis (distillation followed by thermal treatment
in a decarbonization furnace).
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5.0 DOE ROCKY FLATS SITE - PLUTONIUM DISPOSITION PROGRAM
The Residue Process Demonstration and Test (D&T) Program is currently underway at the
Rocky Flats Environmental Technology Site (RFETS) to examine a variety of processes for
treating and stabilizing plutonium residues in storage at RFETS prior to final disposition. The
D&T program is intended to (1) identify and mitigate residue processing problems that could
preclude the production of an acceptable residue form, (2) provide data necessary for the start of
full-scale operations, (3) evaluate risk mitigation measures, and (4) demonstrate compliance with
storage and disposal criteria. One component of the D&T program involves the use of muffle
furnaces for the vitrification of incinerator ash residues (which may also include sand, slag,
crucible, and graphite fines) that are contaminated with low levels of plutonium (i.e., non-
weapons grade plutonium). Approximately 28,000 kilograms .of ash, sand, slag, crucible, and
graphite fines, with an average plutonium content of less than 10 percent, are present at RFETS.
The D&T research effort that involves use of muffle furnaces for vitrification is being conducted
at Los Alamos National Lab (LANL) on behalf of RFETS.11
5.1 Studies Performed Using Muffle Furnace Treatment Technology
The studies currently associated with RFETS that incorporate the use of muffle furnaces deal
with the vitrification of some forms of plutonium residues (primarily incinerator ash, with some
graphite fines, sand, slag, and crucible residues). Low-temperature vitrification (also referred to
as agglomeration) appears to be a preferred method for treating incinerator ash and graphite
fines; with high-temperature vitrification being pursued as a backup treatment method. High-
temperature vitrification appears more appropriate for immobilizing sand, slag and crucible
residues.
The muffle furnace used in both high- and low-temperature vitrification studies at LANL for the
D&T program is part of a glovebox system. The residue material is first crushed to a uniform
size and a glass frit is added. Studies on frit development have included use of soda-lime silicate
glass, a vanadium-phosphate glass, and an alkali-borosilicate glass. Studies have shown that
make-up of the ash (or other material) and the loading of ash into the glass affect the temperature
required to produce a melted product and full agglomeration. Results of frit studies using low-
temperature vitrification have shown the vanadium-phosphate glass to be the most favorable for
agglomeration, with the alkali-borosilicate glass to be a good alternative. The vanadium-
phosphate glass has a full melt at a temperature of approximately 400 °C (750 °F); the alkali-
borosilicate glass reached a full melt at 650°C to 750°C (1200°F to 1380°F); and the soda-lime
silicate glass reaches a full melt at 900°C (1650°F). Experiments are currently underway to
determine what glass composition and processing operations will be optimal for high-
11 Information on activities related to muffle furnaces used in vitrification studies at
RFETS was provided by Mr. Gregg Nishimoto, DOE Rocky Flats Field Office.
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temperature vitrification of ash residues. This work will build on borosilicate glass and soda-
lime silicate glass formulation research conducted at the Savannah River Site.
Studies of the LANL work using muffle furnaces in the treatment train have not yet been
published. RFETS personnel noted that the final design of all types of furnaces that may be used
will differ considerably depending on the installation (i.e., whether installation is integral with
the glovebox system or not), heating capacity, size, and other factors. Configuration may also
vary considerably in the final design.
5.2 Effectiveness of Muffle Furnace Treatment Technology
Vitrification of graphite fines and slag, slag and crucible residues using a muffle furnace is
showing promising results, in that a monolithic form that appears to microencapsulate the residue
is being produced. Recent results of studies from the vitrification of ash residue are not as
promising. Higher temperatures during the vitrification process have led to foaming of the ash-
glass mixture, especially of the carbonates. Specific glass formulations are being experimented
with. The problems with low-temperature vitrification include reduced glass matrix quality, and
residue macroencapsulation as opposed to microencapsulation.
The leachability tests of these low-temperature vitrification products have not yet yielded
acceptable results. Leachability is a measure of the retention of plutonium constituents within
the treated material matrix in the presence of leaching material (e.g., acids, water, etc.).
Leachability tests are not performed to meet Resource Conservation and Recovery Act (RCRA)
hazardous waste characterization and waste disposal requirements. Rather, the leachability tests
are intended to demonstrate that the plutonium-bearing residue form following treatment will
meet DOE safeguard termination requirements (i.e., the plutonium cannot be more easily
recovered than plutonium in spent nuclear fuel).
5.3 Costs Associated with Muffle Furnace Treatment
The procurement costs associated with individual furnaces are negligible compared to the
installation costs. Procurement costs for a new muffle furnace will vary between approximately
two thousand dollars to over ten thousand dollars, depending on the size and type of furnace
ultimately purchased. Installation costs will run in the hundreds of thousands of dollars to
stripout an existing facility, install new equipment, and obtain the necessary permits to operate
the treatment unit.
5.4 Regulatory Requirements and Standard Practices
Plutonium metals and stabilized plutonium oxides that are stored on site at RFETS prior to
determination of final disposition are managed in accordance with DOE standard DOE-STD-
3013-96 Criteria for Preparing and Packaging Plutonium Metals and Oxides for Long-Term
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Storage. This standard limits per package storage quantities to 4.40 kilograms of plutonium
metals (or materials containing at least 50 percent plutonium by mass) and 5.00 kilograms of
thermally stabilized plutonium oxides. Final off-site disposal of treated plutonium materials will
also require consideration of DOE criteria for nuclear waste disposal (DOE Order 5280.2A).
Numerous studies have been performed against this and additional DOE criteria. However, these
studies contain information on actual quantities and locations of plutonium-bearing materials at
the RFETS. As a result, the information is classified.
The WIPP Waste Acceptance Criteria (WIPP WAC) specifies requirements that must be met for
disposal at WIPP. Incorporated into the WIPP WAC are DOT shipping requirements, which
specify waste form as well as packaging requirements. All residues shipped from RFETS to the
WIPP site will meet DOT and WIPP WAC requirements. RFETS Safe Secure Trailers, which
meet DOT 49 CFR Part 173 requirements, have been designed to withstand the effects of severe
accidents.
Some classified materials at RFETS have been contaminated with plutonium. Currently RFETS
and Lawrence Livermore National Laboratories (LLNL) are undergoing negotiations for sending
the classified items to the LLNL for processing and final disposal at the Nevada Test Site (NTS).
Disposal of this material will comply with NTS waste acceptance criteria in NVO-325.
Shipment of treated plutonium-bearing residues to the Waste Isolation Pilot Plant (WIPP) will
require compliance with waste acceptance criteria (WAC) in WIPP-DOE-069. It is the intention
of RFETS vitrification treatment process to meet the lengthy requirements of the WIPP WAC so
that treated plutonium-containing materials may be shipped to the WIPP facility.
5.5 Off-Gas Effluent Treatment
High-temperature vitrification of ash residues and graphite fines results in the oxidation of
carbon in these residues to carbon .monoxide and carbon dioxide. One problem that has been
noted is the formation of flammable carbon-monoxide gas in the muffle furnace. Low-
temperature vitrification appears to minimize the formation of carbon monoxide. The
vitrification set up includes an off-gas cooling system and an off-gas scrubber downstream of the
muffle furnace.
5.6 Additional Information
Information collected on the physical transformation of ash and related material following
vitrification treatment in muffle furnaces included data on residue loading. Loading refers to
how much of the plutonium-bearing residue may be incorporated into a particular glass melt
batch. The ash loading rate in the treatment process has been noted to affect the temperature of
the muffle furnace and the formation of glass crystallization. Full-scale sample studies with 20
percent and 40 percent ash have produced agglomeration. DOE Savannah River Site has
conducted studies on percent of ash loading with both soda-lime silicate and borosilicate glass.
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Results showed a 50 percent weight ash loading to the soda-lime silicate glass produced a full
melt, and an 80 percent weight ash loading to the borosilicate glass produced a full melt. The
loading rate was deemed important to the ease of pouring the liquefied mixture. Too high an ash
loading increased the viscosity and decreased the ease of pouring of the melted material and
ultimately interfered with glass crystallization.
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6.0 CONCLUSIONS
Muffle furnaces provide a high-powered heat source to treat plutonium and plutonium-bearing
materials. The furnaces are used in conjunction with other plutonium disposition technologies at
the three DOE facilities investigated in this report.
Work at Savannah River is currently being summarized in a major report that will be used by
DOE to decide between vitrification and ceramics immobilization of plutonium-bearing residues
in storage at Savannah River. It is anticipated that the treatment method decision will affect
other'DOE sites with excess plutonium disposition issues that must be addressed. Muffle
furnaces are not currently used at Savannah River for the vitrification studies being conducted,
but are used in conjunction with ceramic immobilization processes. Muffle furnaces have been
used at Lawrence Livermore National Laboratory for some of the ceramics immobilization
research that is being conducted parallel to the work at Savannah River. However, as indicated
by DOE representatives at Hanford, Savannah River, and Lawrence Livermore sites, muffle
furnaces have been used only because they are bench-top units convenient and suitable for
research purposes. The purpose of the muffle furnace is to provide a heat source, and they do not
necessarily confer any advantage over other types of furnaces.
Muffle furnaces at the Hanford Site have been used to stabilize certain plutonium bearing
materials at the Plutonium Finishing Plant and will continue to be used for this purpose. These
materials are being stabilized only so that they may be stored at Hanford more safely, while
decisions regarding final disposition of excess plutonium are made. Muffle furnaces are not a
major component of research currently underway at the Hanford Site. It is anticipated that
whichever plutonium disposition treatment technology is selected for the Savannah River Site
will be used at Hanford as well.
Muffle furnaces will likely be used at Rocky Flats Environmental Technology Site (RFETS) for
the vitrification treatment of incinerator ash and related materials (sand, slag, crucibles, and
graphite fines). High- and low-temperature vitrification research using muffle furnaces is
currently being conducted at Los Alamos National Laboratory on behalf of RFETS. The final
design of the full-scale vitrification treatment system has not been determined for Rocky Flats,
since research is still in its early stages. It is possible that a furnace, other than a muffle furnace,
may be used as a preferred source of heat for the vitrification process once optimal treatment
parameters are determined through currently ongoing research.
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7.0 REFERENCE SOURCES
7.1 References - Savannah River Site Plutonium Disposition Program
Armantrout, G.A., and L.J. Jardine. 1996. Disposition of Excess Plutonium using "Off-Spec"
MOX Pellets as a Sintered Ceramic Waste Form. Lawrence Livermore National
Laboratory, prepared for submittal to the Waste Management '96 Symposia Working
Towards a Cleaner Environment, Tucson, AZ, February 25-29,3996.
Bickford, D.F., and R. Schumacher. 1994. Vitrification of Hazardous and Radioactive Wastes.
Westinghouse Savannah River Company. Paper prepared for the Fall Meeting of the
American Ceramic Society, Cojumbus, OH, November 14-18,1994.
Ebbinghouse, Bartley B; Richard A. Van Konynenburg; Eric R. Vance; Adam Johnstons;
Rayford G. Anthony; C.V. Phillips; and David J. Wronkiewicz. 1995. Status of
Plutonium Ceramic Immobilization Precesses and Immobilization Forms. Paper prepared
for presentation at the Plutonium Stabilization and Immobilization Workshop sponsored
by the USDOE, EM and MD, Washington DC, December 12-14, 1995.
Ewing, R.C., W.J. Weber, and Werner Lutze. 1995. Ceramics: Durability and Radiation Effects.
Paper prepared for presentation at the Plutonium Stabilization and Immobilization
Workshop sponsored by the USDOE, EM and MD, Washington DC, December 12-14,
1995.
Gray, Leonard W. and Thomas H. Gould. Immobilization Technology Down-selection Radiation
Barrier Approach. Lawrence Livermore National Laboratory, UCRL-ID-127320.
Gray, Leonard W. and Tehmau Kan. 1995. Safety Aspects with Regard to Plutonium Vitrification
Techniques. Lawrence Livermore National Laboratory, UCRL-JC-120907, May 11,
1995.
Gray, L.W., and T. Kan. 1996. Status of Immobilization for Disposition of Surplus Fissile
Material. Lawrence Livermore National Laboratory. Paper prepared for submittal to the
Waste Management Technology in Ceramic and Nuclear Industry, Indianapolis, IN, April
15,1996.
Gray, L.W., T. Kan, and J.M. McKibben. 1996. Immobilization as a Route to Surplus Fissile
Materials Disposition. Lawrence Livermore National Laboratory. Paper prepared for
submittal to the 3rd International Policy Forum: Management & Disposition of Nuclear
Weapons Materials, Lansdowne, VA, March 19-22, 1996.
Gray, Leonard. 1997. Lawrence Livermore National Laboratory. Personal communications.
August 1997.
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Hoenig, C., R. Rozsa, F. Banzan, R. Otto, and J. Grens. 1981. Preparation and Properties of
Synroc D Containing Simulated Savannah River Plant High-level Defense Waste.
Lawrence Livermore National Laboratory, UCRL-53195, July 23,1981.
Johnstons, Adam; Alan Ridal; Don J. Mercer; and E.R. 'Lou' Vance. 1995. Experience Gained
with the Synroc Demonstration Plant at ANSTO and its Relevance to Plutonium
Immobilization. Paper prepared for presentation at the Plutonium Stabilization and
Immobilization Workshop sponsored by the USDOE, EM and MD, Washington DC,
December 12-14, 1995.
Kuhn, N.H. 1995. Use of Savannah River Site Facilities for Glass and Ceramics. Westinghouse
Savannah River Company, prepared for presentation at the Plutonium Stabilization and
Immobilization Workshop sponsored by the USDOE, EM and MD, Washington DC,
December 12-14, 1995.
Keuhn, N.H. 1996. Can-in-Canister Cold Demonstration in DWPF (U). Westinghouse Savannah
River Company, WSRC-TR-96-0226, July 1996.
Marra, James C. 1997. Westinghouse Savannah River Company, Savannah River Site. Personal
communications. August 1997.
Myers, B.R., G.A. Armantrout, and R. Erickson. 1995. Analysis and Section of Processes for the
Disposition of Excess Fissile Material from Nuclear Weapon Dismantlement in the
United States. Lawrence Livermore National Laboratory, UCRL-JC-119874, February
1995.
Oversby, V.M. and E.R. Vance. 1994. Comparison of Ceramic Waste Forms Produced by Hot
Uniaxial Pressing and by Cold Pressing and Sintering. Lawrence Livermore National
Laboratory, September 1994.
Ramsey, William G., Ned E. Bibler, and Thomas F. Meaker. 1995. Compositions and
Durabilities of Glasses for Immobilization of Plutonium. Westinghouse Savannah River
Company. Paper prepared for Waste Management '95 Conference, Tucson, AZ February
26, to March 3, 1995.
Rask, William C. and Alan G. Phillips. 1995. Ceramification: A Plutonium Immobilization
Process. Paper prepared for presentation at the Plutonium Stabilization and
Immobilization Workshop sponsored by the USDOE, EM and MD, Washington DC,
December 12-14, 1995.
Tehmau, Kan and Kent Sullivan. 1995. Glass and Ceramic Immobilization Alternatives and the
Use of New Facilities. Paper prepared for presentation at the Plutonium Stabilization and
Immobilization Workshop sponsored by the USDOE, EM and MD, Washington DC,
December 12-14, 1995.
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7.2 References - Hanford Site Plutonium Disposition Program
Chronisterj Glen. 1997. Plutonium Finishing Plant, Hanford Site. Personal communications in
August 1997.
Cunningham, L.T. 1994. HC-21 Off-Gas Test Procedure, Rev. 1. Westinghouse Hanford
Company, WHC-SD-CP-TC-032, August 1994.
Dayley, L. 1995. Basis Document for Sludge Stabilization, Rev. 1. Westinghouse Hanford
Company, April 1995.
DeVries, M.L. 1994. Heat Exchanger Bypass Test Procedure. Westinghouse Hanford
Company, WHC-SD-CP-TC-031, August 1994.
De Vries, M.L. 1994. Loss/Gain on Ignition Testing for HC-21 C. Westinghouse Hanford
Company, WHC-SD-CP-TP-082, August 1994.
De Vries, M.L. 1994. Sludge Stabilization Boat Material Test Plan. Westinghouse Hanford
Company,, WHC-SD-CP-TP-084, August 1994.
De Vries, M.L. 1994. Engineering Study on Conveyor System for HC-21C. Westinghouse
Hanford Company, WHC-SD-CP-ES-166, September 1994.
De Vries, M.L. 1994. Sludge Stabilization Campaign Blend Plan, Rev. L Westinghouse Hanford
Company, WHC-SD-CP-TI-193, September 1994.
Funston, G.A. 1994. Rocky Flats Ash Test Procedure (Sludge Stabilization). Westinghouse
Hanford Company, WHC-SD-CP-TP-087, August 1994.
Lewis, W.S. 1994. Preliminary Hazards Analysis of Thermal Scrap Stabilization System, Rev. I.
Westinghouse Hanford Company, August 1994.
Lewis, W.S. 1994. Sludge Stabilization Operability Test Report. Westinghouse Hanford
Company, WHC-SD-CP-OTR-15, August 1994.
Lewis, W.S. 1997. Plutonium Finishing Plant, DOE Hanford Site. Personal communications in
August 1997.
U.S. Department of Energy (DOE). 1994. Environmental Assessment: Sludge Stabilization at
the Plutonium Finishing Plant, Hanford Site, Richland, Washington. DO/EA-0978,
October 1994.
U.S. Department of Energy (DOE). 1996. Plutonium Finishing Plant Stabilization Final
Environmental Impact Statement, Hanford Site, Richland, Washington. DOE/EIS-0244-F.
DOE Richland Operations Office, Richland, Washington, May 1996.
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7.3 References - Rocky Flats Plutonium Disposition Program
Becker, G.W., and J. Malvyn McKibben. 1996. Vitrification of Rocky Flats Ash Followed by
Encapsulation in the Defense Waste Processing Facility. Westinghouse Savannah River
Company, WSRC-MS-96-0196. Paper proposed for DOE Spent Nuclear Fuel and Fissile
Material Management Meeting, Reno, Nevada, June 17-20,1996.
Funston, G.A. 1994. Rocky Flats Ash Test Procedure (Sludge Stabilization). Westinghouse
Hanford Company, WHC-SD-CP-TP-087, August 1994.
Garcia, Eduardo. 1996. Annual Progress Report for TTP All 42001, Vacuum Distillation
Separation of Plutonium Salts, DOE Office of Technology Development ESP, Los
Alamos National Laboratory (LANL). June 1,1996.
Haschke, J.M. 1996. Nuclear Material Packaging Project Status and Plans. Los Alamos
National Laboratory (LANL). February 27,1996.
Hildner, Richard A. and Stanley J. Zygmunt. 1996. Applying Modular Concepts to Process and
Authorization Basis Issues for Plutonium Residue Stabilization. Los Alamos National
Laboratory (LANL). Paper submitted to the American Glovebox Society Annual
Meeting, San Diego, CA, July 22-25,1996.
Nishimoto, Gregg. 1997. DOE Rocky Flats Field Office (DOE/RFFO). Personal
communications in August 1997.
Potter, R.C. 1996. Salt Distillation Design Analysis Summary, ESA-DE, Los Alamos National
Laboratory. August 1996.
Rink, Nora A. 1996. 94-1 Research and Development Project Lead Laboratory Support, Status
Report, October 1- December 31, 1996. Los Alamos National Laboratory, LA-13249-
SR.
U.S. Department of Energy DOE. 1996. System Design Document for the Plutonium
Stabilization and Packing System. Report prepared by BNFL under Contract No. DE-
AC03-96SF20948. June 1996.
U.S. Department of Energy (DOE). 1994. Environmental Assessment - Resumption of Thermal
Stabilization of Plutonium Oxide in Building 707 Rocky Flats Plant, Golden, Colorado.
DOE/EA-887. February 1994.
U.S. Department of Energy (DOE). 1994. Finding No Significant Impact Resumption of Thermal
Stabilization of Plutonium Oxide in Building 707. February 1994.
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Veazey, G., R. Nakaoka, and J. Hurd (LANL) and J. Vienna, J. Luey, M. Elliot, and H. Li
(PNNL). 1997. Update of Vitrification Studies for Ash and SS&C (Speakers Slides).
May 20,1997.
7.4 Other References
National Academy of Sciences (NAS), Committee on International Security and Arms Control.
1994. The Management and Disposition of Excess Weapons Plutonium. National
Academy Press, Washington, DC. 1994.
U.S. Department of Energy (DOE). 1995. Summary Report of the Screening Process to
Determine Reasonable Alternatives for Long-Term Disposition of Weapons-Usable
Fissile Materials. March 29, 1995.
U.S. Department of Energy (DOE). 1996. DOE Standard-Criteria for Preparing and
Packaging Plutonium Metals and Oxides for Long-Term Storage. DOE-STD-3013-96.
September 1996.
U.S. Department of Energy (DOE). 1996. Storage and Disposition of Weapons-Usable Fissile
Materials Final Programmatic Environmental Impact Statement. December 1996.
U.S. Department of Energy (DOE). 1997. Record of Decision for the Storage and Disposition of
Weapons-Usable Fissile Materials Final Programmatic Environmental Impact
Statement. January 14, 1997.
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