Dismantling a Nuclear Reactor

AmiMoJo sends in a BBC story about the hardware used to decommission a nuclear reactor: "The device cost £20m to design and build and will operate in highly radioactive conditions inside Dounreay's landmark Dome. Its detachable tool bits cost £100,000 each and weigh between 37-93kg. They will cut and grab 977 metal rods once used to 'breed' plutonium from uranium. ... Once in place, the device will operate in highly radioactive conditions and in a nitrogen atmosphere. Nitrogen prevents any residue of the liquid metal from reacting. Exposure to water or oxygen would cause the metal to catch fire. ... Up to three tool bits will be in use at any one time and can be replaced by another three carried in a special tool box without the need to remove the tool itself from the reactor. The rest of the tool bits will be stored above the reactor and would be fitted into place during service and maintenance breaks."

Comments

Re:Metal? What Metal?

[Baloroth]

Actually, yes. According to Wikipedia, this reactor is cooled by liquid sodium-potassium metal. The BBC mentions it several times as "liquid metal", but never by name, likely because "liquid metal" is a much cooler name than "sodium-potassium." Or because the less scientific might think "Sodium and potassium? You mean salt and the stuff in bananas?" This is BBC, so I'll give them the benefit of the doubt and say the latter. Sadly, its also probably what most people would think. Never mind liquid sodium-potassium is flammable in air, and the idea of radioactive NaK burning gives me the heeblie-jeeblies, as much as I like nuclear power.

Long story short: bad nuclear reactor design, should never be done again. Also, its been being decommissioned since 1977. So, yeah, lets not do that again.

DFR is a fast reactor not a LWR

[cronb]

This story is a bit misleading because the reactor being dismantled is an experimental fast neutron reactor. The materials it is made of were not really designed to be easily disassembled. This is different from a commercial light water reactor where part of the design requirements are being comparatively straightforward to dismantle.

Re:Metal? What Metal?

[Baloroth]

Oh, don't get me wrong: I do still think FBRs are really cool. While I was reading about this reactor, my inner nerd was going "Holy shit, using NaK as a coolant is awesome and kinda badass!" even while it was also going "Holy shit, using a material that can spontaneously explode in air as coolant for nuclear material is a really bad idea!". Many bad ideas are also really cool. Doesn't mean they aren't still bad ideas. Can't even imagine what would happen if the public found out about it. Or if, God forbid, one of these things actually exploded.

Now, something like a Molten Salt Reactor , on the other hand, is both cool and (probably) not a bad idea. And could possibly solve most of the world's ecological problems.