Appendix I to Part 110 - Illustrative List of Reprocessing Plant Components Under NRC Export Licensing Authority
10:2.0.1.1.20.11.139.7.30 : Appendix I
Appendix I to Part 110 - Illustrative List of Reprocessing Plant
Components Under NRC Export Licensing Authority Note:
Reprocessing irradiated nuclear fuel separates plutonium and
uranium from intensely radioactive fission products and other
transuranic elements. Different technical processes can accomplish
this separation. However, over the years Purex has become the most
commonly used and accepted process. Purex involves the dissolution
of irradiated nuclear fuel in nitric acid, followed by separation
of the uranium, plutonium, and fission products by solvent
extraction using a mixture of tributyl phosphate in an organic
diluent.
Purex facilities have process functions similar to each other,
including: Irradiated fuel element chopping, fuel dissolution,
solvent extraction, and process liquor storage. There may also be
equipment for thermal denitration of uranium nitrate, conversion of
plutonium nitrate to oxide metal, and treatment of fission product
waste liquor to a form suitable for long term storage or disposal.
However, the specific type and configuration of the equipment
performing these functions may differ between Purex facilities for
several reasons, including the type and quantity of irradiated
nuclear fuel to be reprocessed and the intended disposition of the
recovered materials, and the safety and maintenance philosophy
incorporated into the design of the facility. A plant for the
reprocessing of irradiated fuel elements includes the equipment and
components which normally come in direct contact with and directly
control the irradiated fuel and the major nuclear material and
fission product processing streams.
(1) Irradiated fuel element chopping machines.
Remotely operated equipment especially designed or prepared for
use in a reprocessing plant and intended to cut, chop, or shear
irradiated nuclear fuel assemblies, bundles, or rods. This
equipment breaches the cladding of the fuel to expose the
irradiated nuclear material to dissolution. Especially designed
metal cutting shears are the most commonly employed, although
advanced equipment, such as lasers, may be used.
(2) Dissolvers.
Critically safe tanks (e.g., small diameter, annular, or slab
tanks) especially designed or prepared for use in a reprocessing
plant, intended for dissolution of irradiated nuclear fuel and
which are capable of withstanding hot, highly corrosive liquid, and
which can be remotely loaded and maintained.
Dissolvers normally receive the chopped-up spent fuel. In these
critically safe vessels, the irradiated nuclear material is
dissolved in nitric acid and the remaining hulls removed from the
process stream.
(3) Solvent extractors and solvent extraction equipment.
Especially designed or prepared solvent extractors such as
packed or pulse columns, mixer settlers, or centrifugal contactors
for use in a plant for the reprocessing of irradiated fuel. Solvent
extractors must be resistant to the corrosive effect of nitric
acid. Solvent extractors are normally fabricated to extremely high
standards (including special welding and inspection and quality
assurance and quality control techniques) out of low carbon
stainless steels, titanium, zirconium, or other high quality
materials.
Solvent extractors both receive the solution of irradiated fuel
from the dissolvers and the organic solution which separates the
uranium, plutonium, and fission products. Solvent extraction
equipment is normally designed to meet strict operating parameters,
such as long operating lifetimes with no maintenance requirements
or adaptability to easy replacement, simplicity of operation and
control, and flexibility for variations in process conditions.
(4) Chemical holding or storage vessels.
Especially designed or prepared holding or storage vessels for
use in a plant for the reprocessing of irradiated fuel. The holding
or storage vessels must be resistant to the corrosive effect of
nitric acid. The holding or storage vessels are normally fabricated
of materials such as low carbon stainless steels, titanium or
zirconium, or other high quality materials. Holding or storage
vessels may be designed for remote operation and maintenance and
may have the following features for control of nuclear
criticality:
(i) Walls or internal structures with a boron equivalent of at
least 2 percent, or
(ii) A maximum diameter of 175 mm (7 in) for cylindrical
vessels, or
(iii) A maximum width of 75 mm (3 in) for either a slab or
annular vessel.
(5) Neutron measurement systems for process control.
Neutron measurement systems especially designed or prepared for
integration and use with automated process control systems in a
plant for the reprocessing of irradiated fuel elements. These
systems involve the capability of active and passive neutron
measurement and discrimination in order to determine the fissile
material quantity and composition. The complete system is composed
of a neutron generator, a neutron detector, amplifiers, and signal
processing electronics.
The scope of this entry does not include neutron detection and
measurement instruments that are designed for nuclear material
accountancy and safeguarding or any other application not related
to integration and use with automated process control systems in a
plant for the reprocessing of irradiated fuel elements.
(6) Plutonium nitrate to plutonium oxide conversion systems.
Complete systems especially designed or prepared for the conversion
of plutonium nitrate to plutonium oxide, in particular adapted so
as to avoid criticality and radiation effects and to minimize
toxicity hazards.
(7) Plutonium metal production systems. Complete systems
especially designed or prepared for the production of plutonium
metal, in particular adapted so as to avoid criticality and
radiation effects and to minimize toxicity hazards.
(8) Process control instrumentation specially designed or
prepared for monitoring or controlling the processing of material
in a reprocessing plant.
(9) Any other components especially designed or prepared for use
in a reprocessing plant or in any of the components described in
this appendix.
[79 FR 39297, July 10, 2014]