science
-
Zaporizhzhia Nuclear Plant 8/11/24
In the news today, there is a fire at the Zaporizhzhia NPP in Ukraine. https://kyivindependent.com/russian-forces-start-fire-at-zaporizhzhia-nuclear-plant-ukraine-says/ From the looks of it, the fire is located in one of the cooling towers. Let me start by saying that the cooling towers are NOT part of the radioactive loop of the nuclear power plants. The water that is…
-
There’s good boiling in a reactor and then there is this.
The Idaho National Lab released a video a while ago that shows something called Departure From Nucleate Boiling (DNB). In high pressure, high temperature environments, water can go from nucleate boiling, which is good, to DNB, in an instant. DNB is about as bad a condition as you can have inside a pressurized water reactor…
-
Enriched Uranium
Iran has been in the news quite a lot lately. Depending on which news organization is scaring you at that particular point in time, they are anywhere from a few months to a few weeks from having enough enriched uranium to make a nuclear weapon. https://www.reuters.com/world/middle-east/iran-can-make-fissile-material-bomb-in-about-12-days-us-official-2023-02-28/ So, what exactly is enriched uranium and why is…
-
Fission Product Barriers
Reuters is reporting that a Ukrainian attack hit the reactor dome of reactor #6 at Zaporizhzhia Nuclear Power Plant (ZNPP). The article is very clear that radiation levels at the plant are stable. This is exactly what I would expect of any attack short of a bunker-buster style bomb. The containment structure is engineered to…
-
Space Weather
We now go live to Ollie Williams for the weather. What’s the weather looking like today, Ollie? So, this is only tangentially connected to nuclear power, but space weather is a thing and can impact the power grid. Earlier today, the earth was hit by a coronal mass ejection (CME) associated with an X class…
-
Why So Many SCRAMs?
I was reviewing the NRC event reports for the last few months and noticed several reactor trips. The normal average is one trip every two years or so. I did not go back and see if in this recent spate of trips any of the units involved were exceeding that rate, it just seemed like…
-
How Much Radiation is Too Much?
Thanks to @nuclearanthro.bsky.social (check out his blog https://deusexatomica.wordpress.com/), we know that a contractor at Los Alamos National Lab accidentally exposed 4 colleagues to radiation while conducting an experiment with Cf-252. The dose ranged between 132 mrem and 195 mrem. As with so much of life, those numbers are meaningless without context. To start, the measure…
-
Running Out of Gas
Nuclear power plants can run a very long time without needing more fuel, but not forever. That would make it a perpetual motion machine, and if you figure that one out you are now a billionaire, so congrats. Every 2 years or so, they have to shut down and replace some of the fuel so…
-
Oh, no! The Reactor is (prompt) Critical!
All bad nuclear movies have that scene where someone shouts “God help us, the reactor is critical!” Every nuclear trained person’s favorite bit of pedantry is to correct people who use the term critical to describe an out of control reactor. Actually, a critical reactor is one where the neutron chain reaction is self sustaining.…
-
Happy New Year! Now, about that earthquake . . .
Since late 2019, it seems like there has been a string of years where things just keep getting worse. 2024 decided to continue that trend by having a magnitude 7.6 earthquake in Japan on New Years Day. Understandably, people get nervous when big earthquakes hit Japan. The nuclear accident at Fukushima happened almost 13 years…
Sleepy Neutron's Nuclear Knowledge 