What are the major nuclear explosion disasters in world history?

Hiroshima Prefecture in the southwest of Honshu, Japan gradually developed into a military stronghold in the middle of19th century. The German fascist 1945, the culprit of World War II, announced its unconditional surrender on May 8. On July 26th, the United States, Britain and China jointly issued the Potsdam Declaration, ordering Japan to surrender unconditionally and quickly, but the Japanese government turned a deaf ear.

In order to force Japan to surrender quickly, the U.S. military dropped the atomic bomb code-named "Little Boy" in the center of Hiroshima, Japan at 8: 00 on August 6 15. "Little Boy" is a uranium bomb with a length of 3 meters and a diameter of 0.7 meters. It contains 60 kilograms of highly enriched uranium and weighs about 4 tons. TNT equivalent is 6.5438+500,000 tons. The atomic bomb exploded in the air 600 meters above the ground, instantly rolling up a huge mushroom-shaped smoke cloud, and Hiroshima city suddenly became a scorching sea of fire.

In this man-made tragedy, the intense light waves produced by the atomic bomb explosion blinded thousands of people. 1 100 million degrees of high temperature makes everything go up in smoke; Radiation rain makes some people die slowly in the next 20 years; The strong wind formed by the shock wave destroyed all the buildings.

According to statistics, before the tragedy, the population of Hiroshima was more than 340,000, and most people died near the explosion center. On that day, more than 88,000 people died and 5 1000 people were injured and missing. More than half of the buildings were damaged to varying degrees. However, this tragedy did not make the Japanese government aware of the seriousness of the problem and still went its own way, so the US military chose to continue.

1In the early morning of August 9, 945 1 1: 02, the US military carried out the second atomic bomb attack on Japan, targeting Nagasaki. This attack dropped the atomic bomb "Fat Man" on the center of Nagasaki, and its destructive power was absolutely no less than last time. "Fatty" is a plutonium bomb, about 3.6 meters long, with a diameter of 1.5 meters and a weight of about 4.9 tons. TNT equivalent is 22,000 tons, and the explosion height is 503 meters. "Fat man" uses a complex "implosion" detonation system, which consists of four different fuzes: air pressure, timing, radar and impact.

The tragedy caused half of Nagasaki's population to be killed or missing that day, and more than 60% of the buildings were destroyed.

Although the two atomic bombs dropped on Hiroshima and Nagasaki were originally intended to force Japan to surrender at an early date, they objectively brought indelible pain to the local people. Even the survivors suffered from radiation sequelae, such as cancer, leukemia and skin burns. But more is the trauma of the soul, which can never be washed away.

Chernobyl nuclear disaster

1970, the Chernobyl nuclear power plant in the northern Ukraine of the former Soviet Union was completed, providing Ukraine with 10% of electricity, and consisting of four nuclear reactors (RBMK- 1000 light water reactor with graphite moderated pressure tube designed by the former Soviet Union in the 1970s).

People generally don't doubt products such as 3C certification, or those well-known products. However,1the big explosion on April 26, 986 changed the trust of the Soviet people in the Chernobyl nuclear power plant and changed all this.

1on the night of April 25, 986, the staff of Chernobyl nuclear power plant were preparing to carry out the safety test of reactor 4, and the test officially began in the early morning of April 26. During the test, in order to improve work efficiency, they deliberately violated the operating rules: a large number of control rods were pulled out, which regulated the temperature of the reactor core. Pulling them out would be a fatal mistake. Because there is no control lever to adjust the temperature, the core is overheated. In the early morning of 26th 1: 23, the staff was lucky enough to violate the rules again and pressed panic button, who shut down the nuclear reactor. At this time, the original intention clashed with the actual situation, and I wanted to stop the test immediately, but the sudden power failure caused the main cooling system to stop working and the reactor was out of control! The water in the core was immediately decomposed into hydrogen and oxygen by strong radiation, and the high concentration of hydrogen and oxygen immediately led to the big explosion of No.4 nuclear reactor.

The 2000-ton steel roof was lifted by the explosive force, and a huge fireball suddenly rose from the reactor, so disaster came. Eight tons of nuclear fuel fragments and high-level radioactive materials were mercilessly thrown into the dark night sky, and the high-temperature and high-speed radiation dose of 2000 degrees Celsius swallowed everything around. There was a cry and a sea of fire on the ground. The evaporated nuclear fuel quickly seeps into the atmosphere, causing strong nuclear radiation in the surrounding areas, which has brought great harm to human beings and creatures.

Half an hour later, rescuers rushed to the No.4 reactor, and all the fire engines, air force and helicopters were used. Nearly 5000 tons of fire extinguishing materials such as dolomite, sand, boride, soil and lead were thrown from the air, and the fire was gradually extinguished. However, radioactive dust was still spreading until May 5, and finally, with the strong support of people from all walks of life, the release of radioactive substances was basically controlled.

In the first few days of the nuclear explosion, many workers and people involved in the aftermath of the accident were killed or injured by high radiation. The survey results show that as many as 300 people died of high-dose radiation, and 30 people died on the spot. After the disaster was slightly controlled, a large number of workers were rushed to the Chernobyl cleanup site. The former Soviet government mobilized hundreds of thousands of people to prevent radioactive materials from entering groundwater. For this purpose, a black building with a length of 160m, a width of10m and a height of 75m was specially built with steel, and all the remaining materials of the No.4 nuclear reactor were enclosed in it. Because of this disaster, this building is called "the sarcophagus".

After the disaster, residents living within 30 kilometers of Fiona Fang, the nuclear power plant, were evacuated, and this area was turned into an isolated area, and no one was allowed to enter or leave at will. Subsequently, the government evacuated a large number of residents from Pripyat, with 6,543,800 people evacuated.

In order to avoid unnecessary panic, the former Soviet Union tried to hide the accident, because the relationship between the Soviet Union and the West was very bad at that time, so it did not inform its neighbors. However, the leaked radioactive dust is inhuman, and there is no such clear concept of national boundaries. Instead, it keeps drifting over northern Europe, eastern Europe and western Europe, and the harm areas are increasing. The radiation wave swept by the wind brought a unexpected trouble to the whole of Europe.

European countries have gradually realized the strange situation of air and issued statements one after another. Sweden claims that the radioactive dust in its atmosphere is five times higher than usual; Denmark claims that the radiation level in the air is four times higher than usual; The radiation level in Finland is the highest, and the radiation level in the north and central parts of Finland is 10 times higher than normal. Romania, Yugoslavia and other countries have also been hurt to varying degrees. Because these countries had conclusive evidence and protested strongly to the Soviet Union, the Soviet Union had to announce the truth of the nuclear explosion.

This nuclear explosion is the biggest nuclear disaster since World War II. In the rescue work, 55,000 people died, 6,543,800 people were disabled, and a large number of ecological refugees were also caused. According to relevant statistics, 6,543.8+0.5 million square kilometers of Soviet territory was directly polluted, of which more than 44,000 square kilometers of land in 654.38+0.2 states in 26 states of Ukraine were polluted by nuclear, and 3 million people were injured. About 6.5438+0.5 million people's thyroid was damaged due to serious damage caused by high dose of radioactive iodine, and the rate of leukemia in children was 2 to 4 times higher than the normal standard. A large number of deformed babies are also caused by human chromosome variation caused by radioactive substances.

Belarus is the place with the most serious nuclear pollution. Of the population of13.5 million in Belarus of 46,000 square kilometers,150,000 people live in areas affected by radioactive substances, and more than 400,000 of them are children. One tenth of these children suffer from various radiation diseases, which is very distressing.

On Russia's 60,000 square kilometers of land, the number of affected states increased from 4 to 17, and the number of victims reached 3 million.

So far, people have not got rid of nuclear pollution. The researchers analyzed the mushrooms collected within 45 ~140km around the nuclear power plant, and found that 90% of the mushrooms contained more than 4,200 Bekkerel, which exceeded the international standard 10 times. Experts say it will take at least one hundred years to eliminate the nuclear pollution caused by this nuclear disaster. Chernobyl used to be the pride of the Soviets, but now it is an indelible pain in human hearts. On February 5, 2000, the President of Ukraine ordered the complete closure of the Chernobyl nuclear power plant. Although the nuclear power plant has been shut down, this "greatest human tragedy of the 20th century" has not ended, but this heavy burden will always be borne by mankind.

Melting of Three Mile Island

1979 at 4: 00 a.m. on March 28th, the operation room of No.2 reactor group of Three Mile Island Nuclear Power Plant in Pennsylvania, USA, was full of people and was in a panic. Two hours later, a large amount of radioactive materials spilled out.

It was not until six days later that the core temperature began to drop and the steam bubbles disappeared-the threat of hydrogen explosion was relieved and the reactor finally paralyzed. The American people were shocked when they heard the news, especially the residents near the nuclear power plant. About 200,000 people were evacuated from this area. People held rallies and demonstrations to stop or shut down nuclear power plants. The governments of the United States and some western European countries also have to re-examine their plans to develop nuclear energy.

The accidental nuclear leakage accident was caused by the failure of the water pump in the secondary circuit: the workers failed to open the valve of the accident cooling system after overhaul a few days ago, which led to the automatic operation of the system and the water in the secondary circuit was still cut off. In this case, when the temperature and pressure in the reactor rise, the reactor will automatically stop and the pressure relief valve will automatically open, releasing part of the steam-water mixture in the core. At the same time, when the pressure in the reactor dropped to the normal value, the pressure relief valve failed to return automatically due to the fault, so that the core coolant continued to flow out and the pressure dropped below the normal value, so the emergency core cooling system was automatically put into operation, but the operator made a wrong judgment and turned off the emergency core cooling system and stopped injecting water into the core. The above management and operation errors are intertwined with equipment failures, which makes a small fault expand rapidly and sharply, and finally causes a serious accident of core melting. Fortunately, in this accident, the main engineering safety facilities were put into use automatically, and the reactor had several safety barriers (fuel cladding, primary pressure boundary and containment, etc.). ), and there were no casualties. Only three staff members received the allowable dose slightly higher than half a year.

The impact of the Lisandao accident on the environment is relatively small, and the radiation dose received by the public within 80 kilometers of the nuclear power plant is less than 1% of the natural background within one year.

This is the first and most serious commercial nuclear accident in the United States, which will change the center and direction of the nuclear industry in the United States, make the American people strongly appeal to the government to take action to stop the construction of nuclear power plants, and widely publicize the dangers of using atomic fuels to generate electricity.

Nuclear explosion of Ural storage tank

1On September 29th, 957, an underground nuclear waste storage tank between the cities of Keshtam and Chelyabinsk suddenly exploded in Urals, a large nuclear industry gathering area of the Soviet Union. Violent explosions send radioactive dust and materials into the sky like volcanic eruptions, and their power is equivalent to 100 times that of the atomic bomb dropped by the United States on Hiroshima in 1945.

A cloud of smoke with a diameter of 10 km with radioactive element strontium 90 rose in the air. More than 65,438+100,000 residents were evacuated from the polluted area immediately. Maidevijeff, a geneticist in the former Soviet Union, estimated that several hundred people died of radiation within a few days after the explosion, and at least 65,438+0,000 people died of radiation that year.

Due to the extremely bad weather, strong winds blew radioactive smoke clouds hundreds of kilometers away, resulting in nuclear pollution in 3,000 square kilometers of the southern Urals, where there was no vegetation and thousands of people suffered from radiation sickness. However, when residents exposed to nuclear radiation are taken to the hospital, doctors do not know about radioactive nuclear medicine, nor do they know how to treat patients according to the amount of radiation received. As a result, many patients are dying. Thousands of people died one year after the accident, and tens of thousands died three years later.

As we all know, plutonium in nuclear waste is an insoluble element, and most of plutonium in nuclear waste in Urals region is absorbed by soil. When water seeps into the soil where plutonium accumulates, plutonium reacts with water, triggering a chain reaction. Water is rapidly heated into steam, and the pressure of steam increases, resulting in a strong explosion, thus causing this appalling nuclear disaster.

In the case that the nuclear waste disposal link was not solved, Khrushchev, then general secretary of the Soviet Union, ordered the furnace to be opened ahead of schedule in order to compete with the Americans, regardless of the opposition of scientists. In order to save the cost of nuclear waste treatment, the Soviet authorities piled up nuclear waste in the Ural forest region, thus forming a large-scale radioactive waste storage site, leaving a major hidden danger.

All roads and railways leading to the area were closed for a year. One year later, a checkpoint will be set up 50 kilometers away from the area. All motor vehicles entering the area (restricted to open) must be inspected, all windows are closed, no photos are allowed, and they must pass at the highest speed without stopping. From 1958 to 1968, residents in this area are not allowed to have children.

Until 1978, 20% of the polluted areas failed to resume production activities.

1989 February, that is, 32 years after the nuclear accident, the Soviet government provided the technical report of the accident to the International Atomic Energy Agency (IAEA), and finally made the accident public. In fact, this is because the Soviet government is under the pressure of public opinion at home and abroad.

The Soviet Union originally planned to build a fast neutron reactor near the town of Keshtum and the world's largest nuclear waste repository in former Las Noyal. This plan caused a fierce debate and protest in the Soviet Union. Perhaps because of this anti-nuclear storm, Soviet officials released information about the Ural nuclear accident, arguing that in the past 30 years, the nuclear accident did not cause obvious and verifiable health hazards.

Pacific nuclear test: bikini incident

1 954 In the early morning of March1,the Japanese fishing boat "Long Fu Maru No.5" was sailing on the high seas about 160 km away from Bikini Atoll in the Pacific Ocean. At this time, a hydrogen bomb nuclear test was conducted on Bikini Atoll. Before dawn, the sky was very bright, and soon a column of smoke rose. Two hours later, the crew of "Long Fu Maru" found a lot of ashes scattered on the ship after the hydrogen bomb exploded. They don't realize that it is the "ash of death" that has radiation effect and will cause harm to human body.

On March 1954, 14, after "Long Fu Pill" returned to Hong Kong, the relevant departments analyzed the "ashes after explosion" brought back by the crew, only to know that it was a new type of hydrogen bomb developed by the United States, and the fact that the United States was developing secret weapons and nuclear weapons was exposed.

At that time, there were 23 crew members on the Long Fu Maru, and all the crew members were immediately sent to Tokyo for treatment. But unfortunately, six months later, Kuboyama Aji, the oldest communication director on board, died at the age of 40.

Afterwards, it was reported that the United States secretly conducted the largest hydrogen bomb explosion test in history in Bikini Atoll. According to scientists' analysis, the destructive power of this hydrogen bomb is no less than that of the atomic bomb dropped by the United States in Hiroshima that year, and it is conservatively estimated that its power is at least 1000 times higher. The test caused nuclear pollution, and the crew of Long Fu V was one of the victims. This incident is called "bikini incident" in Japan.

1945 In August, after the United States dropped the first atomic bomb on Hiroshima, Japan, the Soviet Union began to accelerate the development of the atomic bomb. 1949, the first atomic bomb test in the Soviet Union was successful. The news spread to the United States, causing shock and anxiety in the United States. The military hegemony of the United States has been challenged, so the United States began to develop a more powerful nuclear weapon-the hydrogen bomb. To develop this terrible weapon, a series of nuclear tests are needed. 1946 65438+ 10 In October, after repeated deliberation and investigation, the U.S. Atomic Energy Commission finally selected the Marshall Islands in the Pacific Ocean as the new atomic bomb testing ground. The Marshall Islands became an innocent victim of these nuclear tests.

The Marshall Islands is located in the middle of the Pacific Ocean, with a land area of 1, 8 1 km2. It consists of more than 1200 Oko islands and reefs, distributed in the sea area of more than 2 million square kilometers. 1946 In February, the United States forced the local residents to move, and American engineers drove into bikini atoll and conducted an abominable hydrogen test. Although the Marshallese did not want to leave their ancestral home, they had to move to another island 200 kilometers away in tears under the threat of American naval guns and tanks. What is even more vicious is that the US military did not tell the residents the reasons for the relocation and the possible harm caused by the nuclear test, which finally made the local residents pay a heavy price.

1 952+065438+1October1early in the morning, the world's first hydrogen bomb "Mike" was detonated here. In an instant, nuclear radiation, shock wave and light radiation are 500 times stronger than the atomic bomb dropped on Hiroshima ... openly showing off over the Pacific Ocean. Researchers who observed the explosion of hydrogen bombs 60 kilometers away humorously described that the world's first man-made thermonuclear sun rose.

The successful test explosion of the hydrogen bomb has enabled the United States to regain its dominant position in the field of nuclear weapons, and its mind is a little down-to-earth, thinking that it can rest easy and sleep comfortably. But they forget that a sly rabbit should have three caves, and only one is not enough. 1953 In August, the first hydrogen bomb test in the Soviet Union was successful, which deeply hurt the United States, so the United States decided to explode a more powerful hydrogen bomb, and the Marshall people's real nightmare came.

The two countries are fighting like two children. 1954, 1 In March, the United States dropped a hydrogen bomb with a predicted TNT equivalent of 6 million tons on Bikini Atoll in Marshall Islands. At about 6: 45, the hydrogen bomb exploded about two meters above the ground. The scene of the explosion quickly stunned the observers: this can never be an explosion of 6 million tons! Because they found that the island where the hydrogen bomb was located and two nearby islands disappeared from sight at the moment of explosion. The American aerial observation plane found that the place where the hydrogen bomb was originally placed suddenly became a deep lake. The Great Lakes are nearly 2 kilometers wide and 80 meters deep. People can clearly see the lights on the island 220 kilometers away from the center of the explosion. Afterwards, according to the calculation of American scientists, the explosion equivalent of this hydrogen bomb was as high as150,000 tons, which was more than twice as large as originally estimated. The United States tested and exploded the most powerful nuclear weapon in the world at that time, and the sense of balance recovered a lot, but all this happiness was based on the suffering of others.

Due to the failure to predict the explosive power, the US military failed to notify nearby residents and fishing boats of various countries operating at sea to evacuate in advance, resulting in the largest nuclear pollution incident in the Pacific Ocean. Among them, the deadly permanent nuclear pollution area is nearly 20,000 square kilometers.

After the hydrogen bomb test, the innocent Marshall submitted a petition to the United Nations, demanding that the United States stop its nuclear test in the islands. However, the United States, which regards itself as "democracy and human rights", ignores the life of these islanders, refuses their demands, and clamors that if they ask again, there will be more powerful people waiting for them. It was not until July 1958 that the United States stopped its nuclear test in the Marshall Islands under the pressure of the whole world.

According to incomplete statistics, from 1940 to 1990, the United States conducted thousands of nuclear tests in less than half a century. Among them, 67 nuclear tests were conducted in Marshall Islands alone and 23 in Bikini Atoll. Within a year of 1954, three nuclear weapons with an equivalent of more than100000 tons exploded on the Marshall Islands. The radioactive fallout from these nuclear explosions has drifted to other parts of the islands, causing skin burns, hair loss, nausea and vomiting for many people. Thyroid diseases and malignant tumors have also become common diseases in this region, and all this is not unknown to the United States, but to meet the ambition of striving for global hegemony, experiments have been conducted again and again.

Although residual radiation has experienced nearly 60 years of wind and rain in these areas, it has already mixed into the soil, making local food and drinking water a source of radiation pollution, and people have to transport necessary daily necessities from other places. Decades have passed, and American warships and testers have gone, but they have left permanent trauma and pain to the Marshall Islands and this vast Pacific Ocean. It's like people had a nightmare, and they don't want this to happen again.