We know that human life is very fragile in the face of the forces of nature. In the struggle with nature for thousands of years, human beings have used their wisdom to transform nature, so that we can get a safer and more comfortable life. In the hundreds of years after the Industrial Revolution, human technology has become more and more powerful, and our cities and the original natural environment have been completely different, which can be said to be a fully transformed society.
Although we are now free from the jungle, beasts and other threats, are we really safe? Without the dangers of nature, everything that human beings themselves have created can also destroy our lives and even cause great disasters no less than natural disasters.
Human development is not only to make life better, the clouds of war still hang over our heads, and human beings in war will also burst out of creativity for various purposes. For example, after the discovery of nuclear energy, humans quickly applied it to weapons research, invented and put into use the atomic bomb, and its power shocked the world.
After the end of World War II, people began to think about using this energy for the benefit of mankind, and finally turned nuclear fission into controllable, and built many nuclear power plants to provide a steady stream of energy for mankind. However, after all, nuclear power plants use a powerful energy source, and in the process of application over the years, there have been some shocking accidents, which are still affecting human society today, making us worried.
Among the nuclear accidents that mankind has experienced, the Chernobyl accident is definitely the one with the greatest impact and the heaviest casualties. The accident was due to the fact that the power of the nuclear power plant was already extremely large, and secondly, because the accident was particularly tragic, which shocked the whole world.
On April 25, 1986, the Fourth Reactor at the Chernobyl Nuclear Power Plant was regularly repaired and tested, but the testers did not operate in full accordance with the safety rules and regulations, and later in order to remedy the part of the operation error, most of the control levers were removed, leaving only six, but the number of safety was at least 30.
The engineers quickly paid the price for their luck. As a result of a massive explosion of water vapor under improper handling, the fuel rods began to melt, and after that, an explosion occurred, lifting the cement lid of the reactor's surface, weighing up to 2,000 tons. Numerous radioactive materials spread to the outside world through the explosion, and the entire town of Pripyat was shrouded in intense nuclear radiation.
Whether it was the fire brigade, the rescue team or the ordinary people around them who arrived immediately, they paid a huge price, and nuclear radiation directly caused tens of thousands of people to suffer from deadly diseases. Unlike other disasters, the effects of nuclear radiation are long-standing, and pripyat is a "dead city" without residents after the Chernobyl accident until now.
After the accident, the Soviet Union quickly built a "sarcophagus" out of up to 400,000 cubic meters of concrete and 7,300 tons of steel, completely sealing off Reactor Four. So after this completely enclosed "sarcophagus" is built, is the radiation controlled and it becomes safe?
This is not the case, because there is something even more terrible in Chernobyl, and that is the "elephant foot". Despite its name, it has nothing to do with animals, but is actually the wreckage of melted nuclear fuel and furnace cores. After the accident, the hot material gradually melted through the building, continued to flow down like lava from a volcanic eruption, and finally stopped at the bottom of the Corridor 217 pipeline.
Known as "Krem," the substance is arguably the most radioactive in the world, and generally only appears after a serious nuclear accident. In the investigation that followed the accident, the researchers risked their lives to go to the underground pipe and filmed the pile of material with a long-range camera, which was still in high temperatures, and the radiation around it was as high as 12,000 roentgen per hour, enough to completely destroy a person's body in a few days.
Because this pile of matter looks a lot like an elephant's foot, people call it an "elephant foot." After discovering this pile of high-risk material, the Soviet authorities decided to retrieve some samples of "elephant feet" for study.
So the rescue team tried to sample with a machine trolley, but found that the pile of hot material was still very hard, and finally even used rifles and armor-piercing shells to successfully shoot some "elephant foot" fragments.
The substances were sent to the laboratory, and it was found that at least they had begun to cool, and would not continue to sink for the time being, coming into the aquifer and continuing to spread outward. That's thanks to the fact that after the Chernobyl accident, more than 400 miners worked overtime to build a cooling channel under the reactor so that the material inside the reactor could be cooled down quickly.
The elephant's feet are gradually cooling, and the sarcophagus has been built, so is Chernobyl safe? Ordinary people may think so, but scholars who have really participated in the Chernobyl rescue and research will not think so. In 1996, a Kazakh nuclear physicist named Artur Konev came to Chernobyl again, and he was one of the designers of the "sarcophagus".
Although the sarcophagus was designed with decades in mind, he believes that after only a decade has passed, the sarcophagus has reached its limits. People at the time did not know what Konev had encountered inside the sarcophagus, but only that two years later, Europe helped Ukraine to reinforce Chernobyl again and build additional protective shields.
It wasn't until 2013, when a photograph appeared online, that part of the truth of the exploration was revealed. The picture shows the pipe where the "elephant foot" is located, and an engineer is probing next to the elephant foot. Who is this person and who did the photography? Information about the elephant's feet is very limited, is this eerie photo full of graininess the product of post-synthesis?
It was later learned from the source and description of the photograph that it was the "elephant foot" photograph taken when Konev entered the sarcophagus in 1996. The physicist was so close to this huge radiation source, where was he now, and did he survive?
Later, people found Konev and found that the old man, who was now in his old age, was still alive. Why was he so lucky? Konev himself said that it was because when he went to the room where the elephant's foot was, the radiation material of the elephant's foot had been reduced much less than it had been after ten years of decay, and he was not seriously affected in the protective suit, so he was able to survive.
Generally speaking, every 7 hours of nuclear radiation material, the amount of radiation will be reduced by about 10 times, so after ten years of cooling and decay, the elephant's foot has been relatively safe, and he has survived.
Konev's research led to the start of the Safety Dome Project, a "arch" made mainly of steel that will be draped directly over Reactor 4 and sarcophagus, taking more than 20 years before it was officially completed in 2018.
In the process, in 2009, a nuclear engineer re-entered the room where the elephant's foot was located, and the temperature of the phenomenon foot had dropped to a point close to room temperature, almost safe. However, this does not mean that this will be the case in the future, because we must always face a severe test from nature, that is, rain.
This is not sensational, in May 2021, the amount of neutrons in the room above the elephant's feet is rising, which means that the elephant's feet are likely to be gradually awakening again, and the culprit is the rain. To figure this out, we must first understand what role water plays in nuclear reactions.
In order to control nuclear fission, it is necessary to reduce the neutron velocity released by uranium to ensure that it can carry out chain reactions, and the size of hydrogen atoms in water is similar to neutrons, so it acts as a "neutron moderator" in a controllable nuclear fission reaction, which can reduce the speed of neutrons to about one ten-thousandth of the original, so its role in nuclear power plants is pivotal.
The temperature of the elephant foot gradually becomes lower and lower during the years of cooling, the nuclear reaction is naturally getting lower and lower, and the amount of radiation is gradually reduced. A large part of the neutrons released by the uranium raw material are directly flying out because they are too fast, so there is no way to generate a chain reaction. However, if water appears again in the room of the elephant foot, then these neutrons will once again be slowed down by hydrogen atoms, thus continuing to carry out the chain reaction, that is, the re-ignition of the "elephant foot".
Rainwater gradually seeps into the ground year after year, and gadolinium nitrate solutions that can absorb neutrons cannot enter here, and elephant feet once again enter a very dangerous situation. Scientists are full of worries about what the future holds, but believe that no one wants to see Chernobyl "resurrected" again, and we hope that calm can be truly restored here after decades of suffering.
Thirty-five years have passed since the Chernobyl accident, but it is still affecting the human world. In the aftermath of this disaster, nuclear power plants are still being built, and similar nuclear power plant accidents are still happening. Nuclear energy is indeed a powerful enough energy source, but it is precisely because of its strength that it will break free from the shackles of human beings in various situations and cause us harm.
After one accident after another, in addition to making people remember that they must strictly follow the operating procedures to deal with these dangerous energy sources, it also reminds people that people should not only be satisfied with the study of this material, we should have safer and more powerful energy.
In recent years, scientists have been working on controlled nuclear fusion, which can release much more powerful energy than nuclear fission and is safer to operate than controlled nuclear fission. If we can really fully grasp this energy source, then there will be no need to take the risk of building today's nuclear power plants, and society will move forward faster and better.
It is hoped that scientists from all over the world can make a breakthrough as soon as possible, so that the dangers and accidents of nuclear power plants will become history completely, and that innocent people will not be sacrificed because of this, and countless happy families will be broken in the disaster.