Can Nuclear Get Greener? The Green Benefits of Depleted Uranium De-conversion

ar power as a sustainable, environmentally-soundThe depleted UF6 tails mentioned in step 5 above
source of electricity is enjoying a comeback inhave historically been stored in large steel
terms of public opinion, but it still faces public andcylinders and ignored for years, or even decades.
environmental challenges. On the one hand, theIn the U.S. alone, there is already in excess of 1.6
near zero-carbon emissions characteristic ofbillion pounds of stored depleted UF6 stored in
nuclear power plants is attractive to industry andenough cylinders that if you were to line them up
environmentalists alike. On the other hand,end-to-end they would stretch for more than 130
concerns remain about potentially-harmfulmiles.
environmental effects of the uranium-based fuelsAt the present time, a vast amount of the
that make it possible.enriched uranium required to fuel the existing U.S.
Nearly all of the concern with nuclear power hasnuclear reactors actually is imported from
focused upon the back end of the fuel cycle,overseas. There is, however, a significant shift in
namely the storage and disposal of spent fuel aseffect towards domestic commercial uranium
high-level waste. While spent fuel has been theenrichment. Therefore, the proper management
major focus issue surrounding nuclear power,and storage of these domestically-produced
there is actually another disposal issue at the frontdepleted UF6 tails will become an important issue
end of the fuel cycle: that of dealing with theconfronting the nuclear industry.
large quantities of depleted uranium hexafluoride,Direct Disposal of Depleted Tails is Not Acceptable
which is a by-product of the uranium enrichmentDepleted UF6 is a chemical form of uranium that
process.cannot be directly disposed because it is
Since the beginning of the nuclear power erachemically reactive. Therefore, in order to dispose
approximately 60 years ago, there has neverof depleted UF6, some or all of the fluorine must
been an economical solution for the managementbe removed in a de-conversion process. This
of the large quantities of these depleted UF6 tails.de-conversion process changes the uranium to a
And yet, an anticipated shift in the near futurenon-reactive (or less-reactive) oxide state. In this
from foreign to domestic enrichment of uraniumnew granular or powder, solid state, the depleted
will result in a significant increase in depleted UF6uranium can be disposed in approved and licensed
tails produced in the U.S..low-level radioactive waste landfills.
A new commercial concept for an environmentallyHistorically, there has been little or no economic
friendly de-conversion process is currently beingincentive for de-conversion since the fluorine has
advanced. The process design extracts high purityeffectively been wasted. However, the anticipated
fluoride from the depleted tails using theirdramatic growth in U.S. commercial enrichment
patented process. This process iscreates a need to address the management of
environmentally-friendly, energy saving, and itdepleted UF6 produced from commercial
allows new and useful products to be created asenrichment companies and the new de-conversion
a result.process can extract value.
A Brief Overview of Nuclear Fuel CycleA Green De-Conversion Solution for the Nuclear
To understand the meaning ofFuel Cycle Industry
“depleted” uranium andThe de-conversion process design is both
de-conversion, it is useful to have an overview ofenvironmentally-friendly and economically-valuable.
the nuclear fuel cycle.The process utilizes a proprietary Fluorine
A form of uranium, enriched in the U235 isotope,Extraction Process (FEP) to produce high-purity
is used as fuel in nuclear reactors. In order to usefluoride gas. FEP can be used to produce a variety
uranium as a nuclear fuel, it must first beof economically-viable pure fluoride gases.
enriched, as follows:There are several aspects of this new depleted
1. Uranium that is mined from the earth isuranium de-conversion process that clearly
converted into uranium oxide or “yellowdemonstrate its role as a “green
cake.”solution” for the front end of the nuclear
2. The yellow cake is converted to UF6 gasfuel cycle.
through a multi-step chemical process usingFirst, de-conversion itself is effectively a recycling
various chemicals, including fluorine. In the process,process in which valuable fluoride material is
the uranium is converted into UF6 gas.recovered from the depleted uranium.
3. The UF6 gas is passed through a enrichmentSecond, some of the products produced by
process at an enrichment facility. In thefluorine extraction are used in manufacturing thin
enrichment process, the U235 atoms present infilms and photovoltaic (PV) materials for solar
the UF6 gas are enriched significantly from theirapplications.
naturally-occurring levels.Third, producing fluoride products using FEP will
4. The enriched UF6 is then processed intosave millions of pounds of CO2 emissions because
uranium oxide and fabricated into nuclear fuel.of the energy efficiency of this process
5. However, about 90% of the UF6 emergescompared to conventional production methods.
from the enrichment process as depleted UF6, orAs the nuclear fuel enrichment process
“tails,” in which the concentrationincreasingly takes place on U.S. soil, the Fluorine
of the U235 atom has been greatly reduced toExtraction Process will offer a solution which is
the level that is not economically or feasibly usefulboth environmentally-friendly and
for further enrichment to reactor fuel.economically-valuable.