SoylentNews is people
SoylentNews
from the more-then-just-a-fission-expedition dept.
Arthur T Knackerbracket has found the following story:
The road to cleaner, meltdown-proof nuclear power has taken a big step forward. Researchers at NRG, a Dutch nuclear materials firm, have begun the first tests of nuclear fission using thorium salts since experiments ended at Oak Ridge National Laboratory in the early 1970s.
Thorium has several advantages over uranium, the fuel that powers most nuclear reactors in service today. First, it's much harder to weaponize. Second, as we pointed out last year in a long read on thorium-salt reactors, designs that call for using it in a liquid form are, essentially, self-regulating and fail-safe.
The team at NRG is testing several reactor designs [javascript required] on a small scale at first. The first experiment is on a setup called a molten-salt fast reactor, which burns thorium salt and in theory should also be able to consume spent nuclear fuel from typical uranium fission reactions.
The tests come amid renewed global interest in thorium. While updated models of uranium-fueled power plants are struggling mightily to get off the ground in the U.S., several startup companies are exploring molten-salt reactors. China, meanwhile, is charging ahead with big plans for its nuclear industry, including a heavy bet on thorium-based reactors. The country plans to have the first such power plants hooked up to the grid inside 15 years. If they pull it off, it might just help usher in a safer future for nuclear power.
-- submitted from IRC
(Score: 5, Interesting) by Aiwendil on Saturday August 26 2017, @08:50AM (2 children)
Since you already have a hot online processing plant you could also use the 22 day window to separate out the Pa233 and wait for it to decay to U233.
U233 is in many regards quite similar to Pu239 including being the other commonly suggested initial-load (and is the intended driver fuel) for Th reactors (you could also use HEU as initial load).
(Or one could just use a design that has better neutron economy)
There are quite a few reactor designs that can be safely built by people able to build ships, quite frankly all but the most pushing-the-envelope reactors can be built like this (however - most countries requires a few magnitudes more safety than is needed). Some reactors (CANDU, maybe PIUS) even was designed with this in mind.
TIL that perpetuity is 3-60 years. Just a quick FYI, they are considering _partially_ lifting the madatory evacuation order for Futaba (the town neighbouring the Fukushima-I plant to the north, and yes, that is the "ghost town" used in most scary-media-stuff).
Not really a challange; get permits [ok, this is hard] and then just defuel it, hire a few guards and you're done (Ågesta is currently used as a (non-nuclear) training area for the fire department, the reactor is still there but they don't have access to it).
If you also want dismantling wait 20-120 years (, maybe send in a robotic unit to wash the insides), and then send in a robotic cutter (kinda like how they are doing at Sellafield right now) and later dismantle it like any other chemical plant.The issues are impatient people that also insist on dismantling (never heard/seen why they do that)
Also, the reactors are still within their safe lifetime - most of then are safer today than when they're were built. (We havn't found the upper safe or technical lifetime for reactors yet, we just know it is _at_least_ 25 years if you don't do any upgrades or more than basic maintenance. Pretty much all powerreactors have had extensive upgrades).
Add a release-filter and the releases are cut to some 3% (the swedes tried to sell such to the japanese in the 90s, the japanese didn't buy, now those filters are a requirement for BWR restarts in japan), have nearby portable generators and/or change the main pressure valves (to modern design) to non-electric to really lower the risk of entering the same failure mode.
(Score: 2) by zeigerpuppy on Saturday August 26 2017, @04:32PM (1 child)
I would challenge the assertion that they're safer today. Embrittlement of the reactor vessels which raises the transition temperature (from ductile to brittle) is a significant issue. There have been some reports that this played a part in the meldown/through of Fukushima 1 as the cooling was too fast initially.
(Score: 2) by Aiwendil on Saturday August 26 2017, @05:43PM
The Fukushima I 1-4 (1&2 in particular) was severly neglected in terms if upgrades and inspections - to the point where they wouldn't have passed inspection in some countries.
But yeah, I agree that a fast cooldown (or ramp-up) probably would be a potential issue, but newer instrumentation and control (outside of japan that tends to be upgraded every 20-30 years, with the new policies japan will be in line with the rest of the world) would assert better control on the cooldown and thereby increase margins. (They are less safe than what a newly built Mark 1 with modern control would; be but yet safer than what a 1960s/early 70s reactor with that era's control was).
(Fun thing here btw - older reactor pressure vessels[RPV] actually had a lot bigger margin of error than modern RPVs has, mainly due to cruder understanding made the designers err further into the side of caution)