Nuclear Lifecycle 3

What percentage of natural uranuim is fissile U-235?

• 1.5%
• 5%
• 0.1%
• 0.7%

In the wet conversion process, what method is used to extract the uranium?

• Ion exchange

• Solvent extraction

• Calcination

• Reduction

What is the product in the conversion process?

• UF6

• UF4

• UO3

• UO2

Which is the most energy intensive part of the nuclear fuel cycle?

• Mining

• Enrichment

• Conversion

• Milling

What happens to the Separative Work Units as U enrichment levels are increased?

• The SWUs decrease as U enrichment levels are increased.
• The SWUs remain constant regardless of U enrichment levels.
• The SWUs are zero for high U enrichment levels.

• The SWUs increase as U enrichment levels are increased.

Why does the curve flatten for SWU vs U enrichment at enrichment levels above 4-5%?

• The curve flattens due to increased demand for uranium.
• The curve flattens because of higher costs in production.
• The curve flattens due to the mass of U is also decreasing.

• The curve flattens as a result of improved technology in enrichment.

What would happen to the cost of enrichment if the feed assay was increased?

• The cost of enrichment would remain the same.
• The cost of enrichment would decrease.
• The cost of enrichment would fluctuate unpredictably.
• The cost of enrichment would increase significantly.

Which method is currently used for enrichment?

• Centrifugation

• Gaseous diffusion

• CRISLA

• Atomic photo-ionisation

Why must reprocessed U be enriched separately to fresh U?

• U232 and U236 concentrate with U235 during enrichment

• U232 is a strong gamma emitter and requires shielding

• U236 is a neutron absorber

• It is old Magnox fuel

Why is it important to keep UF6 containers sealed and dry?

• UF6 is highly radioactive

• It reacts with water to produce HF which is extremely corrosive

• It will deconvert back to UF4

• Uranium is toxic