The radioactive team welcomes everyone interested in the history of the Chernobyl disaster! Our today's video will be devoted to one of the important elements on the territory of the Chernobyl nuclear power plant, namely to such an object as an ISF - 1.
In this video we will continue to tell and show you how the body of a nuclear power plant works. You will have a unique opportunity to see a number of frames that previously could not be found in the public domain. Turn on the video quality to the maximum, grab your drinks and sit down more comfortably. We begin!
What kind of object is this with a strange name HOYAT?
ISF - 1 (Like HYATT regency) is not the name of a respectable hotel that our tourists often think of. This is another abbreviation that stands for spent nuclear fuel storage. Although in a sense this object can be called a haven for radioactive fuel, it is true only temporary.
The storage facility, which will be discussed in our today's release, is located on the territory of the ChNPP industrial site, just two hundred meters from the very fourth block.
This facility was commissioned in September 1986. It was that autumn that complex work was carried out to decontaminate the station's roofs and work was in full swing on the creation of the well-known "Shelter" object, or as it is called by the people of the Sarcophagus.
ISF-1 is a special storage facility of the so-called "wet type". That is, absolutely all fuel assemblies are located in special pools filled with water. In turn, this type of storage of fuel assemblies makes it possible to control the parameters of spent fuel and provides reliable biological protection against radioactive radiation.
The main task of the ISF is the temporary storage of spent fuel assemblies from the reactors of the Chernobyl nuclear power plant. As of 2021, spent fuel repository number one ensures the safe storage of all fuel from the RBMK 1000 reactors of the first, second, and third power units of the Chernobyl NPP.
ISF 1 has in its arsenal four workers and one reserve pool in which spent fuel is stored. Fuel assemblies are located in special tubular cases immersed in water. And now we will tell you a little theory, but in simple human language, so that it becomes clear to you why everything is so complicated.
Some time after the main part of the uranium in the nuclear fuel burns out and the fuel assembly can no longer support the chain reaction, it is removed from the reactor and transferred to a special spent fuel pool, where it is kept for 3 to 5 years. During this time, the activity of the assembly decreases, and at the same time the self-heating of this assembly stops.
The fuel assembly, which was taken out of the reactor, continues to hold a chain reaction of fission of uranium atoms. Atoms decay into a large number of radioactive elements, forming a total of several tens of isotopes, each of which is radioactive. All together they are superimposed, their power, their activity is summed up, and as a result, when the fuel assembly is removed from the reactor core, it emits very powerful radioactive radiation.
In addition to the fact that the assembly emits a huge amount of radiation, it naturally heats up very much, since radioactive decay is accompanied by the release of energy. The greater the intensity of this radioactive decay itself, the more intensively the assembly heats up. The very few tens of isotopes that are formed in fuel assemblies have different half-lives from a few seconds to many, many thousands of years. It is for this reason that the fuel assemblies are kept for several years in the storage pools in order to reduce their overall activity and so that they stop heating up so much. But after three to five years, the assembly still continues to "fade" very strongly, since there is still a significant amount of radionuclides in it. Due to the fact that the storage pools in the central hall of the reactor have a limited number of places, the assemblies are sent to temporary storage facilities, which operate on the same principle as the storage pools in the central hall of each power unit of the plant.
It is important to say that spent nuclear fuel is not radioactive waste. The point is that none of the existing types of reactors can provide complete fuel burnup in fuel assemblies. This means that the spent fuel can re-enter the fuel cycle. The only problem that prevents you from doing fuel reprocessing is the cost of this reprocessing. It is almost equal to the cost of producing fresh fuel. But time passes, and technologies keep pace with the times. For this reason, it makes sense to store spent assemblies securely in special storage facilities until better times, when this valuable source of raw materials can be efficiently recycled and reused.