Presentation about the accident at the Chernobyl nuclear power plant. Presentation on the topic: Accident at the Chernobyl nuclear power plant

By the May holidays, everything was already ready, the displays described with slogans, the demonstration scripts had already been submitted for approval by the authorities, and the restaurants were preparing holiday menus. Everyone was anxiously awaiting 3 days off. Dreams of the holidays collapsed on April 26, when a terrible explosion occurred at the Chernobyl Nuclear Power Plant, which changed the lives of all residents of this youngest and most beautiful city in the USSR. Today it is an exclusion zone, the very name of which gives goosebumps. The city is surrounded by barbed wire and entry is allowed only with passes... For the May holidays, the storefronts described with slogans were all ready, the demonstration scripts had already been submitted for approval by the authorities, and the restaurants were preparing holiday menus. Everyone was anxiously awaiting 3 days off. Dreams of the holidays collapsed on April 26, when a terrible explosion occurred at the Chernobyl Nuclear Power Plant, which changed the lives of all residents of this youngest and most beautiful city in the USSR. Today it is an exclusion zone, the very name of which gives goosebumps. The city is surrounded by barbed wire and entry is allowed only with passes...

Chernobyl accident destruction on April 26, 1986 of the fourth power unit of the Chernobyl nuclear power plant, located on the territory of Ukraine (at that time the Ukrainian SSR). The destruction was explosive, the reactor was completely destroyed, and environment A large amount of radioactive substances were released. The accident is regarded as the largest of its kind in the entire history of nuclear energy, both in terms of the estimated number of people killed and affected by its consequences, and in terms of economic damage. At the time of the accident, the Chernobyl nuclear power plant was the most powerful in the USSR. The actual number of deaths during the first 3 months is estimated at 31 people; long-term effects of radiation, identified over the next 15 years, caused the death of 60 to 80 people. The Chernobyl accident was the destruction on April 26, 1986 of the fourth power unit of the Chernobyl nuclear power plant, located on the territory of Ukraine (at that time the Ukrainian SSR). The destruction was explosive, the reactor was completely destroyed, and a large amount of radioactive substances was released into the environment. The accident is regarded as the largest of its kind in the entire history of nuclear energy, both in terms of the estimated number of people killed and affected by its consequences, and in terms of economic damage. At the time of the accident, the Chernobyl nuclear power plant was the most powerful in the USSR. The actual number of deaths during the first 3 months is estimated at 31 people; long-term effects of radiation, identified over the next 15 years, caused the death of 60 to 80 people.

As a result of the explosion at the Chernobyl Nuclear Power Plant, an area of ​​4000 sq. km was cordoned off. The city of Pripyat and all settlements within a radius of 30 km were completely evacuated. But some who did not accept life in a foreign land returned immediately... As a result of the explosion at the Chernobyl Nuclear Power Plant, the territory was cordoned off with an area of ​​4000 sq. km. The city of Pripyat and all settlements within a radius of 30 km were completely evacuated. But some who did not accept life in a foreign land returned immediately... Village of Kopachi City of Pripyat

At approximately 1:24 am on April 26, 1986, a release occurred at the 4th power unit of the Chernobyl nuclear power plant, which completely destroyed the reactor. The building of the power unit partially collapsed, killing 2 people: MCP (Main Circulation Pump) pump operator Valery Khodemchuk (body was not found, buried under the rubble of two 130-ton separator drums), and commissioning plant employee Vladimir Shashenok (died from a spinal fracture and numerous burns at 6:00 in the Pripyat medical unit, on the morning of April 26th). A fire started in various rooms and on the roof. Subsequently, the remains of the core melted. A mixture of molten metal, sand, concrete and fuel particles spread throughout the sub-reactor rooms. As a result of the accident, radioactive substances were released into the environment, including isotopes of uranium, plutonium, iodine-131 (half-life 8 days), cesium-134 (half-life 2 years), cesium-137 (half-life 33 years), strontium -90 (half-life 28 years). At approximately 1:24 am on April 26, 1986, a release occurred at the 4th power unit of the Chernobyl nuclear power plant, which completely destroyed the reactor. The building of the power unit partially collapsed, killing 2 people: MCP (Main Circulation Pump) pump operator Valery Khodemchuk (body was not found, buried under the rubble of two 130-ton separator drums), and commissioning plant employee Vladimir Shashenok (died from a spinal fracture and numerous burns at 6:00 in the Pripyat medical unit, on the morning of April 26th). A fire started in various rooms and on the roof. Subsequently, the remains of the core melted. A mixture of molten metal, sand, concrete and fuel particles spread throughout the sub-reactor rooms. As a result of the accident, radioactive substances were released into the environment, including isotopes of uranium, plutonium, iodine-131 (half-life 8 days), cesium-134 (half-life 2 years), cesium-137 (half-life 33 years), strontium -90 (half-life 28 years). Graphite, metal and nuclear fuel, that’s what happened after the explosion...

In the first days after the accident, the population of the 10-kilometer zone was evacuated. In the following days, the population of other settlements 30 kilometer zone. It was forbidden to take things with you; many were evacuated in home clothes. To avoid fanning panic, it was reported that the evacuees would return home in three days. They were not allowed to take domestic animals with them; subsequently, detachments were formed from among the military and local hunters to shoot abandoned domestic and wild animals. In the first days after the accident, the population of the 10-kilometer zone was evacuated. In the following days, the population of other settlements within the 30-kilometer zone was evacuated. It was forbidden to take things with you; many were evacuated in home clothes. To avoid fanning panic, it was reported that the evacuees would return home in three days. They were not allowed to take domestic animals with them; subsequently, detachments were formed from among the military and local hunters to shoot abandoned domestic and wild animals.

Until 2000, the 3rd power unit continued its work, currently there are 3000 people in the exclusion zone - ecologists, geologists and other specialists, 300 people out of these three thousand are residents who remained... Until 2000, the 3rd power unit continued its work, Currently, there are 3,000 people in the exclusion zone - ecologists, geologists and other specialists, 300 people out of these three thousand are residents who remained... Control panel of reactor 4, 3rd power unit. Corridor connecting control room 4, turbine hall and reactor shop.

Specialists sent to carry out work on and around the emergency unit, as well as military units, both regular and made up of urgently called up reservists, began to arrive in the 30-kilometer zone around the Chernobyl nuclear power plant. They all later began to be called “liquidators.” The liquidators worked in the dangerous zone in shifts: those who received the maximum permissible dose of radiation left, and others came to take their place. The bulk of the work was completed over the course of years and approximately one person took part in it. The total number of liquidators (including subsequent years) was about. In the 30-kilometer zone around the Chernobyl nuclear power plant, specialists sent to carry out work on the emergency unit and around it, as well as military units, both regular and made up of urgently called up reservists, began to arrive. They all later began to be called “liquidators.” The liquidators worked in the dangerous zone in shifts: those who received the maximum permissible dose of radiation left, and others came to take their place. The bulk of the work was completed over the course of years and approximately one person took part in it. The total number of liquidators (including subsequent years) was approximately

On April 26, 1986, at 1 hour 24 minutes, two explosions were heard in succession at the 4th power unit of the Chernobyl nuclear power plant, which announced to the whole world about the accomplished tragedy of the passing century. A powerful man-made disaster occurred at a nuclear facility.

• The explosions led to the complete destruction of the reactor and its core, cooling systems, and the reactor hall building.
• Reinforced concrete and metal structures, graphite blocks and their pieces were thrown onto the roof of the turbine hall and into the area around the nuclear power plant.

• From the mouth of the reactor rose, several hundred meters high, a column of combustion products, a powerful stream of gaseous radioactivity. Of the 190 tons of nuclear fuel, 90% entered the earth's atmosphere. According to scientists, the release of radionuclides is equal, according to various estimates, to four or more explosions in X Iroshima.

There is no roof, part of the wall is destroyed... The lights went out, the phone went off. Floors are collapsing. The floor is shaking. The premises are filled with either steam, fog, or dust. Short circuit sparks flash. Radiation monitoring devices are off the charts. Hot radioactive water flows everywhere.

At 1 hour 30 minutes, fire brigade units for the protection of the nuclear power plant, the station itself and the city of Pripyat, under the command of lieutenants Viktor Kibenko (left) and Vladimir Pravik, arrived at the scene of the disaster. Firefighters took on the full power of radioactive radiation while extinguishing a fire on the roof of the turbine hall. Later, fire brigades arrived from Chernobyl, Kyiv and other areas, commanded by Major Telyatnikov. By 5 o'clock in the morning the fire was localized

Both and their subordinates received high doses of radiation; they could not be saved.

Both were awarded the title of Hero Soviet Union posthumously. All of them are buried at the Mitinskoye cemetery in Moscow.

As a result of the accident, it was decided to evacuate all populated areas in the area of ​​30 kilometers. The city of Pripyat with a population of more than 50,000 people was also included in this list.

Today, thirty years later, the city is empty.

Thousands of people from all over former USSR were called up and sent to eliminate the consequences of the disaster. Work to eliminate the accident was carried out mainly manually.

They used shovels to remove the top layer of soil on the territory of the nuclear power plant, threw off pieces of reinforcement and graphite from the roof of the turbine room by hand, and washed away radioactive dirt with rags inside the station.

Some radio-controlled mechanisms performing work to remove debris could not withstand high level radiation and went beyond the control of the operators

The destroyed core had contact with the atmosphere; everything there was bubbling, making noise, humming, like fiery hell

The government, having listened to the advice of experts, decided to close it and fill the crater with heat-absorbing materials capable of filtering fire and ash.

Therefore, from April 27 to May 10, pilots of the USSR Air Force, risking their flesh and lives, made hundreds of flights over the active zone. They dropped from helicopters thousands and thousands of bags of sand, clay, dolomite, boron, as well as large packages of lead, which ranked first by weight - 2,400 tons.

Deactivation It was important to prevent the expansion of the radioactive contamination zone. For this purpose, they fought against dust formation by spraying the surface with a special mixture, used polymer coatings, used the vacuum suction cleaning method (vacuum cleaners), and manually wiped objects with fabrics soaked in decontamination solutions.

Hundreds of vehicles, from firefighters to helicopters, were involved in extinguishing the reactor.

As a result of the high radioactive background, most of the cars were contaminated with radiation. A special parking lot was made for them, which is still preserved.

On the tenth day the emission power dropped -

up to one percent. A nervous release set in.

In the first days, when the eruption was in full swing, air currents moved towards Belarus...

Its height was 61 meters, the greatest thickness of the walls was

18 meters. The construction of the “sarcophagus” was carried out using self-propelled cranes equipped with television surveillance equipment. It has an exhaust ventilation system with air purification, a forced cooling system, and to prevent an increase in neutron activity, tanks with boron solution are installed on the roof.

“Rossokha” is a huge field filled with rows of corroded trucks, fire trucks, bulldozers, armored personnel carriers and other radioactive equipment - and in the middle, as a symbol of complete hopelessness, helicopters drooped with their blades, which were never destined to take to the air again...

Under the influence of radiation, apples grew to incredible sizes

Foal with five limbs

30 years ago there was an accident at the Chernobyl nuclear power plant...

Novosibirsk

Iskitim, Novosibirsk region

Chernobyl, a city in Ukraine, on the Pripyat River, at its confluence with the Kiev Reservoir. District center, with developed industry: iron foundry and cheese-making factories, fleet repair and maintenance base; workshop of the production and artistic association, medical school.

On April 25, 1986, a shutdown of the 4th power unit of the Chernobyl nuclear power plant was planned for the next scheduled maintenance. During such shutdowns, various routine procedures and equipment tests are usually carried out.

At approximately 1:24 am on April 26, 1986, a release occurred at the 4th power unit of the Chernobyl nuclear power plant, which completely destroyed the reactor. The power unit building partially collapsed, killing 2 people.

A fire started in various rooms and on the roof. Subsequently, the remains of the core melted. As a result of the accident, radioactive substances were released into the environment.

The accident is regarded as the largest of its kind in the entire history of nuclear energy, both in terms of the estimated number of people killed and affected by its consequences, and in terms of economic damage. At the time of the accident, the Chernobyl nuclear power plant was the most powerful in the USSR. The actual death toll during the first 3 months is estimated at 31; long-term effects of radiation, identified over the next 15 years, caused the death of 60 to 80 people.

Unlike the bombings of Hiroshima and Nagasaki, the explosion resembled a very powerful “dirty bomb” - the main damaging factor was radioactive contamination. The radioactive cloud from the accident passed over the European part of the USSR, Eastern Europe and Scandinavia. Approximately 60% of the radioactive fallout fell on the territory of Belarus. About 200,000 people were evacuated from contaminated areas.

evacuation

About 50,000 people were evacuated from the city of Pripyat alone in one day.

In the first days after the accident, the population of the 10-kilometer zone was evacuated. In the following days, the population of other settlements within the 30-kilometer zone was evacuated. It was forbidden to take things with you; many were evacuated in home clothes. To avoid fanning panic, it was reported that the evacuees would return home in three days. They were not allowed to take pets with them (they were subsequently shot).

While all foreign media were talking about the threat to people's lives, and a map of air flows in Central and Eastern Europe was shown on TV screens, festive demonstrations and celebrations dedicated to May Day were held in Kiev and other cities of Ukraine and Belarus. Those responsible for concealing information subsequently explained their decision by the need to prevent panic among the population

Elimination of consequences of the accident

Target:

1. Consideration of the problem of using the atom for peaceful purposes and overcoming possible crisis moments.

2. Demonstration using the example of Chernobyl that man-made disasters are caused not only by failures in equipment and mechanisms, but also by incorrect actions of personnel and other employees of the nuclear power plant

3. Developing in students a sense of responsibility for the fate of their country, their compatriots, the understanding that each person must approach the performance of their work efficiently and seriously.

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GOU secondary school 1981 Moscow 25 years of the accident at the Chernobyl nuclear power plant Physics teacher Elena Anatolyevna Alikueva 2011

Chernobyl Nuclear Power Plant Complete destruction of the Chernobyl reactor, Pripyat, Ukrainian SSR A radioactive cloud passed over the USSR, Eastern Europe, Scandinavia Chernobyl accident - April 26, 1986

Release into the environment Uranium isotopes Plutonium Iodine – 131 (half-life – 8 days) Cesium – 134 (half-life – 2 years) Cesium – 137 (half-life – 33 years) Strontium – 190 (half-life – 28 years)

Chronology of events At 1:23:39 - emergency protection signal (AZ-5) Then a signal about a rapid increase in power Recording systems fail Emergency protection rods stopped 1:23:47 - 1:23:50 (3 seconds!) - explosion , the reactor is completely destroyed

Presumable causes were suggested: Hydrogen explosion - chemical nature of the explosion Thermal explosion - nuclear nature Steam explosion INSAG “... the accident was the result of an unlikely coincidence of a number of violations of rules and regulations by the operating personnel; the accident acquired catastrophic consequences due to the fact that the reactor was brought into an unregulated state. » Causes of the accident

Disadvantages of the reactor As of April 1986, the RBMK reactor had dozens of violations and deviations from the safety rules in force at that time. Due to the incorrectly chosen physical and design parameters of the core by its developers, the reactor was a system dynamically unstable with respect to disturbances both in power and steam content.

Operator errors Thus, the most significant errors of operational personnel should be called: interpretation of the proposed tests as electrical; improper preparation of the test program, including in terms of regulation of safety measures; significant deviations from the program at the stage of preparation for the experiment and its conduct; disabling safety systems, including emergency reactor protection

Consequences of the accident

Informing the population

Elimination of consequences of the accident

Impact of the accident on human health

Radiation doses

Oncological diseases The thyroid gland is one of the organs most at risk of cancer as a result of radioactive contamination, because it accumulates iodine-131; The risk is especially high for children. Between 1990 and 1998, more than 4,000 cases of thyroid cancer were reported among those who were under 18 years of age at the time of the accident.

An increase in the number of congenital pathologies was found in various regions of Belarus between 1986 and 1994. Infant mortality is very high in all three countries affected by the Chernobyl accident.

Other diseases Cataract Cardiovascular diseases Decreased immunity

Dead city 25 years later

In memory of the victims

This must not happen again!

CONTENT

The beginning of the tragedy

Causes of the accident

Liquidation

Consequences

Sources

START A L O T R A G E D I

At 01:23 an explosion occurred in the fourth power unit of the nuclear power plant in Chernobyl.

“But then something happened that even the wildest imagination could not predict. After a slight decrease, the reactor power suddenly began to increase at an ever-increasing speed, and alarm signals appeared. L. Toptunov shouted about an emergency increase in power. But he was unable to do anything. All he could do was hold down the AZ button, the control rods went into the active zone. He has no other means at his disposal. And everyone else too. A. Akimov sharply shouted: “Shut down the reactor!” He jumped to the control panel and de-energized the electromagnetic clutches of the control rod drives. The action is correct, but useless.

After all, the CPS logic, that is, all its elements of logical circuits, worked correctly, the rods went into the zone. Now it’s clear: after pressing the AZ button there were no correct actions, there were no means of salvation... With a short interval, two powerful explosion. The AZ rods stopped moving without going even half way. They had nowhere else to go. At one hour, twenty-three minutes, forty-seven seconds, the reactor was destroyed by a power run-up using prompt neutrons. This is a collapse, the ultimate disaster that can happen at a power reactor. They didn’t think about it, they didn’t prepare for it.”

CAUSES OF VAULTS

The Chernobyl disaster does not have one single cause. The disaster became possible as a result of a series of mistakes and miscalculations - political, managerial and technical.

• The dangers of nuclear power were underestimated. This led to the decision to massively build nuclear power plants.
• A number of miscalculations were made when designing a nuclear power plant.
• Low qualifications and low discipline of personnel. The experiment, which failed during the day, was continued at night by young shift supervisors, in the absence of the station’s chief specialists, which led to gross violation instructions (in particular, control rods were left in the working area of ​​the reactor much less than the critical norm.)
• In addition, failure to notify people about the accident in a timely manner aggravated the consequences and significantly increased the number of victims.

Operator errors.

The most significant mistakes of operational personnel include:

• interpretation of the proposed tests as electrical
• inadequate preparation of the test program, including regarding the regulation of safety measures
• significant deviations from the program at the stage of preparation for the experiment and its implementation
• disabling safety systems, including reactor emergency protections

NPP operation diagram

L I K V I D A T I O N

The explosion itself claimed the lives of two people: one died immediately, the second was taken to the hospital. Firefighters were the first to arrive at the scene of the disaster and set to work - putting out the fire. They extinguished it in canvas overalls and helmets. They had no other means of protection, and they did not know about the radiation threat - only a couple of hours later information began to spread that this fire was somewhat different from the usual one. By morning, the firefighters put out the flames and began to faint - radiation damage began to take its toll. 136 employees and rescuers who found themselves at the station that day received a huge dose of radiation, and one in four died in the first months after the accident.

Over the next three years, a total of about half a million people were involved in eliminating the consequences of the explosion (almost half of them were conscripts, many of whom were actually sent to Chernobyl by force). The disaster site itself was covered with a mixture of lead, boron and dolomite, after which a concrete sarcophagus was erected over the reactor.

Nevertheless, the amount of radioactive substances released into the air immediately after the accident and in the first weeks after it was enormous. Neither before nor after have such numbers found themselves in densely populated areas.

CONSEQUENCES

Emissions to the environment

Isotopes of uranium

Plutonium

Iodine – 131 (half-life – 8 days)

Cesium – 134 (half-life – 2 years)

Cesium – 137 (half-life 33 years)

Strontium – 190 (half-life – 28 years)

Impact of the accident on human health

The thyroid gland is one of the organs most at risk of cancer from radioactive contamination because it accumulates iodine-131; the risk is especially high for children

Between 1990 and 1998, more than 4,000 cases of thyroid cancer were reported among those under 18 years of age at the time of the accident.

Other diseases

Leukemia

Congenital deformities

Cataract

Cardiovascular diseases

Decreased immunity

The number of children with Down syndrome born in Belarus in the 80s - 90s. The peak incidence of the disease occurred in January 1987.

Long-term consequences and modern times

As a result of the explosion at the Chernobyl reactor, Ukraine suffered serious, long-term consequences. Because of the incident, many small villages and cities were buried forever - experts, using heavy equipment, buried hundreds of small settlements. Due to the fact that the infection spread to nearby areas due to the explosion, the government was forced to withdraw over 5 million hectares of land from agricultural use.

The radiation that spread far from the Chernobyl nuclear power plant affected, in particular, Leningrad region, Chuvashia and Mordovia - in these areas, as in Belarus and European countries, it fell in the form of precipitation. As a result of this disaster, an exclusion zone within a radius of 30 km was formed around the Chernobyl nuclear power plant; no one lives in these territories to this day.

In modern times, the Chernobyl nuclear power plant is not in operation, but many fans of “black” tourism - the number of such people, according to travel companies, number in the tens of thousands. It is allowed to stay in the exclusion zone, in particular in the city of Pripyat, for a short time, but tourists are prohibited from eating any products not brought from outside.

SOURCES

http://www.lib.ru/MEMUARY/CHERNOBYL/dyatlow.txt

https://ru.wikipedia.org/wiki/ Chernobyl

http://ria.ru/trend/chernobilskaya_katastrofa/