Energy 2022

Source: Flowcharts

For those who prefer a lecture:

Do molten salt reactors suffer similar xenon decay effects as in solid fueled reactors?

• Xenon is a byproduct of uranium fission and exists as a neutron absorber. Shutting down the reactor does not halt xenon production in solid fuel rods and it absorbs neutrons inhibiting restarting fission.
• Xenon is to fission reactors like a layer of ash on a wood fire. The ash inhibits oxygen so the wood does not burn as quickly. Stroking the fire, knocks the ash off and the fire significantly increases.
• The Chernobyl disaster was in part caused by the operations staff turning the reactor to MAX-on not remembering the xenon was inhibiting fission. When the xenon decayed away, the reactor went to very hot, max power, and scram insertion of the carbon tipped control rods triggered the steam explosion.
• Xenon, a gas, is easily separated from a liquid salt reactor but there may be non-gas, neutron absorbing isotopes with similar characteristics.

I like the higher temperatures of molten salt reactors because of improved thermodynamic efficiency in the heat engine powered generators. If freed from the xenon like effects, they should be able to throttle in fairly short time frames ... especially if there are multiple, smaller thermal engines. Like a multiple engine rocket, the more engines, the easier to throttle the power while maintaining thermal efficiency.

Not covered in the YouTube video, there are significant material challenges. A melted salt is highly reactive and few metals or other materials can withstand the heat and chemical reactivity. If nothing else, the neutron flux transforms nearby elements into different, often less robust elements. Perhaps zirconium alloys?

However, it [zirconium rjw] will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present. - Wiki: https://en.wikipedia.org/wiki/Zirconium​

Bob Wilson