reprocessing. reprocessing is tricky reprocessing: separating the elements in the highly radioactive...

13
Reprocessing

Upload: doris-boyd

Post on 31-Dec-2015

241 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Reprocessing

Page 2: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Reprocessing is tricky

Page 3: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Reprocessing: separating the elements in the highly radioactive spent fuel

• Small reactors that produce medical isotopes reprocess the spent fuel to obtain the highly radioactive isotopes for medical uses.

• Production reactors reprocess the spent fuel to obtain the plutonium for bombs.

• Some countries, but not the US, reprocess the spent fuel from big reactors that produce electricity, retrieve the plutonium, and use the plutonium in mixed-oxide reactor (MOX) fuel.

Page 4: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Medical Isotopes

• Reprocessing the spent fuel from small research reactors to obtain highly-radioactive isotopes for medical uses is not very controversial.

• Those worried about nuclear terrorism would like these small reactors to be renovated to run on LEU which is not a nuclear weapons proliferation risk.

Page 5: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Reprocessing creates highly radioactive acid

• Robotically dissolving the highly-radioactive spent nuclear fuel in acid to separate out the different elements produces highly-radioactive acid.

• The highly-radioactive acid produced from large-scale reprocessing is an environmental danger.

Page 6: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Mayak, Russia

• On Sept 29, 1957, a highly-radioactive acid storage tank from reprocessing in Mayak, Russia exploded when its cooling system failed.

• This accident was the third most serious nuclear accident after Fukushima and Chernobyl.

Page 7: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

East Urals Radioactive Trace (EURT)

Page 8: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Obtaining plutonium from spent fuel

• Plutonium is not a naturally-occurring element.

• Plutonium is not highly radioactive.• Pu-239 is produced in nuclear reactors.• Pu-239 is fissile.• The atomic bomb exploded over Nagasaki,

Japan on August 9, 1945 had Pu-239 as its fissile material.

Page 9: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Hanford Site

• Plutonium for the Nagasaki bomb and many other cold war nuclear weapons was reprocessed out of the spent fuel from production reactors at the Hanford Site in the state of Washington.

• 53 million gallons of highly-radioactive acid waste are still stored at the Hanford in underground tanks.

Page 10: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

The Hanford Site and the Columbia River

Page 11: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Single-walled and double-walled

• The original single-shell storage tanks at Hanford were leaking highly-radioactive waste .

• Much of the fluid from 177 single-shelled plants was moved to 28 newer double-shelled tanks, but construction flaws in half of these new tanks have resulted in further leaking.

• And water is leaking into the old single-shelled tanks leaching out highly-radioactive sludge.

Page 12: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

Plutonium is not highly radioactive

• HEU and Pu are the materials for nuclear weapons.

• HEU and Pu are not highly radioactive.

• People can make weapons from HEU or Pu without having to worry about radiation exposure.

• Weapons made of HEU or Pu are not easy to detect with radiation detectors.

Page 13: Reprocessing. Reprocessing is tricky Reprocessing: separating the elements in the highly radioactive spent fuel Small reactors that produce medical isotopes

US doesn’t reprocess spent fuel from utility reactors

• Reprocessing spent fuel is expensive.

• Reprocessing spent fuel is creates new highly-radioactive acid waste which is another waste disposal problem.

• Reprocessing spent fuel makes the not highly-radioactive but fissile plutonium accessible.