It was a partial meltdown in a pressurized water reactor, it cannot be compared to Chernobyl, it's a completely different technology. PWRs can't explode like what happened in Chernobyl.
The containment vessel held, and most of the radiation released was in the form of xenon and krypton gas vented from the reactor.
“ It was later found that about half the core had melted, and the cladding around 90% of the fuel rods had failed,[21][76] with 5 ft (1.5 m) of the core gone, and around 20 short tons (18 t) of uranium flowing to the bottom head of the pressure vessel, forming a mass of corium.[77] The reactor vessel—the second level of containment after the cladding—maintained integrity and contained the damaged fuel with nearly all of the radioactive isotopes in the core.”
Definitely not Chernobyl, but it was a significant amount of damage to the reactor. It was totaled.
There is a lot to be said for big, strong containment vessels. Fukishima's was too small and overpressure broke it open. Chernobyl didn't have one. Three Mile Island had a good one.
Many of the "small modular reactor" schemes say they don't need a big, strong, expensive containment vessel because, reasons. You can read those arguments for NuScale in NRC documents. The prototype was going to be built at the Idaho National Laboratory, formerly the National Reactor Testing Station, which is in outer nowhere, just in case.
PWR is a "Pressurized Water Reactor" using (light) water under pressure as the primary coolant. The Chernobyl block #4 RBMK-1000 was certainly a PWR.
While the precise mechanism by which the #4 reactor in Chernobyl was destroyed in 1986 was rooted in the flawed design combined with unsafe operation, this does not mean that other reactor designs cannot fail catastrophically with loss of containment and release of radioactive material. Particularly when operated outside of their specification through operator error, accidents or a combination thereof.
RBMK is not considered a PWR because it is graphite-moderated. Most reactors are classified first by their moderator. PWRs and BWRs are both LWRs, moderated by light water, as opposed to HWRs moderated by heavy water, or graphite-moderated reactors like RBMK, or fast reactors which have no moderator at all.
Any reactor can fail and any can be operated safely. The reactivity coefficients of RBMK made it harder to control, perhaps, than a PWR. Modifications made after the Chernobyl accident have improved this.
The main issue with Chernobyl 4 was its lack of a containment building. Even so, the response was an over-reaction that made the situation worse.
RBMKs are not PWRs, full stop. You're completely wrong. These terms have clear, precise established meanings, you cannot redefine them willy nilly to suit your rhetorical needs.
> PWRs can't explode like what happened in Chernobyl.
No, sadly.
PWR's sure can explode (due to hydrogen, vapor...).
The root causes will not be identical to Chernobyl's causes, and the containment will probably limit leaks for a while (theoretically at least a few days), but they sure can explode.
It also happened at Fukushima.
Some protective measures are PACs and containment, however nothing can guarantee that an explosion won't happen, nor that dangerous radionuclides won't leak outside the plant.
If the HBO show had the science somwhat correct, then the operators did everything they could to make it go boom. In failure modes already defined and warned about.
lazide|2 years ago
It took years to find that out though.
The containment vessel held, and most of the radiation released was in the form of xenon and krypton gas vented from the reactor.
“ It was later found that about half the core had melted, and the cladding around 90% of the fuel rods had failed,[21][76] with 5 ft (1.5 m) of the core gone, and around 20 short tons (18 t) of uranium flowing to the bottom head of the pressure vessel, forming a mass of corium.[77] The reactor vessel—the second level of containment after the cladding—maintained integrity and contained the damaged fuel with nearly all of the radioactive isotopes in the core.”
Definitely not Chernobyl, but it was a significant amount of damage to the reactor. It was totaled.
Animats|2 years ago
Many of the "small modular reactor" schemes say they don't need a big, strong, expensive containment vessel because, reasons. You can read those arguments for NuScale in NRC documents. The prototype was going to be built at the Idaho National Laboratory, formerly the National Reactor Testing Station, which is in outer nowhere, just in case.
redprince|2 years ago
While the precise mechanism by which the #4 reactor in Chernobyl was destroyed in 1986 was rooted in the flawed design combined with unsafe operation, this does not mean that other reactor designs cannot fail catastrophically with loss of containment and release of radioactive material. Particularly when operated outside of their specification through operator error, accidents or a combination thereof.
beefman|2 years ago
Any reactor can fail and any can be operated safely. The reactivity coefficients of RBMK made it harder to control, perhaps, than a PWR. Modifications made after the Chernobyl accident have improved this.
The main issue with Chernobyl 4 was its lack of a containment building. Even so, the response was an over-reaction that made the situation worse.
lupusreal|2 years ago
natmaka|2 years ago
No, sadly.
PWR's sure can explode (due to hydrogen, vapor...).
The root causes will not be identical to Chernobyl's causes, and the containment will probably limit leaks for a while (theoretically at least a few days), but they sure can explode.
It also happened at Fukushima.
Some protective measures are PACs and containment, however nothing can guarantee that an explosion won't happen, nor that dangerous radionuclides won't leak outside the plant.
PAC: https://en.wikipedia.org/wiki/Passive_autocatalytic_recombin...
Containment: https://en.wikipedia.org/wiki/Containment_building
ChatGTP|2 years ago
NegativeK|2 years ago
olivermuty|2 years ago