Used Nuclear Fuel / Depleted Uranium - Is It a Waste or a Resource (Kenneth Kok)

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Is It a Waste or a Resource? Kenneth D. Kok


Resource utilization

Resource value

Potential going forward


    

Current uranium use – 70,000 MT/yr Generation – 365 GW of electric power Easily available uranium - 5,500,000 MT Less than 100 years supply Current utilization - < 0.5% of mined uranium Uranium fission energy yield – 1 MWd/g


In 1962 the USAEC Stated to President Kennedy: “This restudy made it apparent that, for the long-term benefit of the country, and indeed of the whole world, it was time we placed relatively more emphasis on the longer-range and more difficult problem of breeder reactors, which can make use of nearly all of our uranium and thorium reserves, instead of the less than one per cent of the uranium and very little of the thorium utilized in the present types of reactors. Only by the use of breeders would we really solve the problem of adequate energy supply for future generations.�


Recoverable natural uranium worldwide ◦ At $130/kg – 5,327,000 MT ◦ At $260/kg – 7,097,000 MT

Used reactor fuel ◦ US - 70,000 MT ◦ Worldwide – 240,000 MT

Depleted uranium – ◦ US – 775,000 MT ◦ Worldwide – 1,500,000 MT


Product Assay - % 2.00 3.00 4.00 5.00 20.00 93.00

Tails Assay - % 0.25 0.25 0.25 0.25 0.25 0.25

Feed kg 3.72 5.85 7.98 10.11 42.02 197.34

Product kg 1.00 1.00 1.00 1.00 1.00 1.00

Tails kg 2.72 4.85 6.98 9.11 41.02 196.34

The amount of natural uranium feed required to produce 1 kg of enriched uranium product. At a 4% enrichment over 85% of the original uranium becomes part of the DU inventory.


Calculation of the uranium burn-up where: • 1000 MW power reactor • 33% Conversion efficiency • 90% Availability • 3 yr Fuel residence time • 70 MT Fuel load


Given 4% enriched uranium implies: ◦ 12.5 % of the original uranium becomes usable reactor fuel ◦ 87.5% is added to the DU stockpile

Given 70 MT of reactor fuel: ◦ 4.3% of the uranium is burned ◦ 95.7% remains in the used fuel

Therefore only about 0.5 % of the mined uranium is used to produce power,


Energy content of available uranium in the US Material

MT

MWdt

Quadt*

Used Reactor Fuel

70,000

70E+09

5,730

Depleted Uranium

775,000

775E+09

63,500

Uranium Resources

207,000

207E+09

16,900

1,052,000

1,053E+09

86,030

Total *

1 Quad = 1.0E+15 Btu , 1 MWd = 8.18E+8 Btu



The value of uranium calculated based on petroleum at $100/barrel

Amount

MT

70,000

Depleted Uranium 775,000

Energy Content Petroleum Equivalent Value Base Oil = $100/Bbl

Btu

5.73E+18

6.35E+19

Bbl

994 Billion

11,000 Billion

$99.4 Trillion

$1,199 Trillion

Used Fuel


The value of the uranium calculated based on coal and natural gas Depleted Uranium 70,000 775,000

Used Fuel

Amount

MT

Energy Content

Btu

5.73E+18

6.35E+19

Coal Equivalent Value Base Coal = $2.65/106 Btu Natural Gas Equivalent Value Base Natural Gas = $3.36/106 Btu

MT

5.10E+14

5.63E+15

$14.3 Trillion

$158 Trillion

5.59E+15

6.20E+16

$14.1 Trillion

$156 Trillion

ft3

Conversion efficiency – Coal 35%, Natural gas 45%, Uranium 33%



ď ˝

ď ˝

Used reactor fuel and DU are energy resources not wastes Used reactor fuel and DU are assets and not liabilities


 Need

fuel reprocessing

 Need

fast reactors


Positives ◦ Performed since the 1940s ◦ Reduces the HLW ◦ Reduces environmental impact

Negatives ◦ Perceived safeguards issue ◦ Generation of liquid waste ◦ Implies transport of spent fuel to a central facility


 

New technology developed by Argonne National Laboratory Does not separate the uranium, plutonium and higher actinides Does not generate liquid waste Can directly produce fast reactor fuel Greatly reduces the radio-toxicisity of the waste stream by reducing the average half life Can be built to operate in conjunction with a single reactor site.


Fast reactors have been designed and operated since the 1940s Will utilize the used fuel and DU to produce electricity Have demonstrated advanced safety features that allow a passive response to accident environments Will use the plutonium and higher actinides as fuel



ď ˝

ď ˝

ď ˝

Used reactor fuel and depleted uranium are both resources and assets The technologies to use these materials for electricity production is known but needs commercialization Adding reprocessing while eliminating enrichment and mining will not have a large economic impact on the cost of power generation.


Developing the IFR has a positive impact on the environment

◦ Materials that are now considered wastes are used to produce usable electrical and thermal energy, minimizing the need for disposal ◦ The total volume of wastes would be reduced and the effective isolation period would be reduced from over 1,000,000 years to 500 years or less ◦ These materials do not have to be extracted from the earth in order to be used ◦ Transport of highly radioactive used fuels would be minimized because the reprocessing process is integral to the IFR concept.


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