So now we’ve talked about all kinds of byproducts, including man-made (Fordite), nature-made (fulgurites), and one that’s a little of both (calthemites). Each of these is beautiful in its own way, but I’m not sure about the beauty and merit of corium — that which is created in a nuclear reactor core during a meltdown.
A necklace made to look like corium. Image via OSS-OSS
Corium has the consistency of lava and is made up of many things, including nuclear fuel, the products of fission, control rods, any structural parts of the reactor that were affected, and products of those parts’ reaction with the surrounding air, water, and steam.
If the reactor vessel itself is breached, corium can include molten concrete from the floor underneath. That said, if corium is hot enough, it can melt any concrete it comes in contact with.
Few types of accidents speak as much to the imagination as those involving nuclear fission. From the unimaginable horrors of the nuclear bombs on Nagasaki and Hiroshima, to the fever-pitch reporting about the accidents at Three Mile Island, Chernobyl and Fukushima, all of these have resulted in many descriptions and visualizations which are merely imaginative flights of fancy, with no connection to physical reality. Due to radiation being invisible with the naked eye and the interpretation of radiation measurements in popular media generally restricted to the harrowing noise from a Geiger counter, the reality of nuclear power accidents in said media has become diluted and often replaced with half-truths and outright lies that feed strongly into fear, uncertainty, and doubt.
Why is it that people are drawn more to nuclear accidents than a disaster like that at Bhopal? What is it that makes the one nuclear bomb on Hiroshima so much more interesting than the firebombing of Tokyo or the flattening of Dresden? Why do we fear nuclear power more than dam failures and the heavy toll of air pollution? If we honestly look at nuclear accidents, it’s clear that invariably the panic afterwards did more damage than the event itself. One might postulate that this is partially due to the sensationalist vibe created around these events, and largely due to a poorly informed public when it comes to topics like nuclear fission and radiation. A situation which is worsened by harmful government policies pertaining to things like disaster response, often inspired by scientifically discredited theories like the Linear No-Threshold (LNT) model which killed so many in the USSR and Japan.
In light of a likely restart of Unit 1 of the Three Mile Island nuclear plant in the near future, it might behoove us to wonder what we might learn from the world’s worst commercial nuclear power disasters. All from the difficult perspective of a world where ideology and hidden agendas do not play a role, as we ask ourselves whether we really should fear the atom.
We’ve enjoyed several videos from [Chornobyl Family] about the computers that controlled the ill-fated nuclear reactor in Chornobyl (or Chernobyl, as it was spelled at the time of the accident). This time (see the video below) they are looking at a high-speed data storage device. You don’t normally think of high-speed and paper tape as going together, but this paper tape reader runs an astonishing 1,500 data units per second. Ok, so that’s not especially fast by today’s standards, but an ASR33, for example, did about 10 characters per second.
An IBM2400 tape drive, for reference, could transfer at least 10 times that amount of data in a second, and a 3400 could do even better. But this is paper tape. Magnetic tape had much higher density and used special tricks to get higher speeds mechanically using vacuum columns. It was still a pretty good trick to move 4 meters of paper tape a second through the machine.
When you think of Chernobyl (or Chornobyl, now), you think of the nuclear accident, of course. But have you ever considered that where there is a nuclear reactor, there is a computer control system? What computers were in control of the infamous reactor? [Chornobyl Family] has the answer in a fascinating video documentary you can see below.
The video shows a bit of the history of Soviet-era control computers. The reactor’s V-30M computer descended from some of these earlier computers. With 20K of core memory, we won’t be impressed today, but that was respectable for the day. The SKALA system will look familiar if you are used to looking at 1970s-era computers.
Before the Chernobyl Nuclear Power Plant (ChNPP, spelled ‘Chornobyl’ in Ukrainian) disaster in 1986, there had been little need for radiation-resistant robots to venture into high-risk zones.
The MF-2 Joker, also used for clearing debris at the Chernobyl NPP #4 disaster site.
Yet in the aftermath of the massive steam explosion at the #4 reactor that ripped the building apart — and spread radioactive material across the USSR and Europe — such robots were badly needed to explore and provide clean-up services. The robots which were developed and deployed in a rush are the subject of a recent video by [The Chornobyl Family].
While some robots were more successful than others, with the MF-2 remote mine handling robot suffering electronic breakdowns, gradually the robots became more refined. As over the years the tasks shifted from disaster management to clean-up and management of the now entombed #4 reactor, so too did the robots. TR-4 and TR-5 were two of the later robots that were developed to take samples of material within the stricken reactor, with many more generations to follow.
The video also reveals the fate of many of these robots. Some are buried in a radioactive disposal site, others are found on the Pripyat terrain, whether set up as a tourist piece, or buried in shrubbery. What’s beyond doubt is that it are these robots that provided invaluable help and saved countless lives, thanks to the engineers behind them.
The Soviet KTP-63-based remote-controlled camera system, including switch and control panel. (Credit: Chernobyl Family on YouTube)
When we picture the Chernobyl Nuclear Power Plant disaster and its aftermath, we tend to recall just the commonly shared video recorded by television crews, but the unsung heroes were definitely the robotic cameras that served to keep an eye on not only the stricken reactor itself but also the sites holding contaminated equipment and debris. These camera systems are the subject of a recent video by the [Chernobyl Family] channel on YouTube, as they tear down, as well as plug in these pinnacles of 1980s vidicon-based Soviet engineering.
When the accident occurred at the #4 reactor at the Chernobyl Nuclear Power Plant (ChNPP) in 1986, engineers not only scrambled to find ways to deal with the immediate aftermath but also to monitor and enter radioactive areas without exposing squishy human tissues. This is where the KTP-63 and KTP-64 cameras come into play. One is reminiscent of your typical security camera, while the other is a special model that uses a mirror instead of directly exposing the lens and tube to radiation. As a result, the latter type was quite hardy. Using a central control panel, multiple cameras could be controlled.
When mounted to remotely controlled robots, these cameras were connected to an umbilical cord that gave operators eyes on the site without risking any lives, making these cameras both literally life-savers and providing a solid template for remote-controlled vehicles in future disaster zones.
Editor’s note: Historically, the site was called Чернобыль, which is romanized to Chernobyl, but as a part of Ukraine, it is now Чорнобиль or Chornobyl. Because the disaster and the power plant occurred in 1986, we’ve used the original name Chernobyl here, as does the YouTube channel.
When the Chernobyl nuclear plant suffered the power output surge that would destroy its #4 reactor, a substance called ‘corium‘ was formed. This originally lava-like substance formed out of the destroyed fuel rods along with surrounding materials, like concrete, that made up the reactor. The corium ultimately cooled down and left large amounts of solid corium in the rooms where it had pooled.
Over the past few days there have been numerous reports in the media regarding a ‘sudden surge’ in neutron flux levels from this corium, with some predicting a ‘second Chernobyl disaster’. Obviously, this has quite a few people alarmed, but how dire are these neutron output changes exactly, and what do they tell us about the condition of the corium inside the ruins of the #4 reactor building? Continue reading “Increased Neutron Levels At Chernobyl-4: How Dangerous Is Corium?”→
