What happened at chernobyl
Chernobyl was a nuclear power plant of USSR (Soviet Russia). Chernobyl nuclear power plant was in Pripyat city of Ukrain. There was a fierce nuclear accident in this plant which was a nightmare for mankind. Thousands of people died in this nuclear disaster. Even today, some people are victims of radioactive radiation caused by this nuclear disaster. This in the form of this incident. Due to this tragedy, questions arose only on nuclear energy. Chernobyl disaster put question mark on nuclear energy and a debate was started around the world.Chernobyl disaster was so much severe that even today, when more than 30 years have passed going to Pripyat city is still not safe.
What happened at chernobyl that night
On 26th April 1986 at 01:23:40 (midnight) Reactor no. 4 had to face a fierce power surge, resulting to that it exploded. As the reactor was not surrounded by any type of harsh resistance vessel, it spread radioactive isotopes in large amounts to the atmosphere and caused an open air to create fire, which caused the excretion of radioactive particles through smoke. The accident occurred during an experiment. Anatoly Dyatlov, deputy chief-engineer of the Chernobyl Nuclear Power Plant was carrying out an experiment.
Read This also- Shivaji Maharaj
Steam turbine test
Let’s know what happened last night and what was the cause of the incident, who were responsible.
Anatoly Dyatlov and other were carrying out an experiment to test the viability of the emergency security emergency core cooling system, which required a normal reactor shutdown process.
In case of emergency shutdown or failure of power grid, there were three backup diesel generators in each Chernobyl reactor. The backup generator can start in 15 seconds, but it takes 60-75 seconds to get full speed and a 5.5 megawatt output is required to run a main pump to Maintains cooling during the process. This one-minute power gap is considered an unacceptable security risk.
it was given the principle that the rotational energy from the steam turbine (because it drops below the residual steam pressure) can be used to generate the necessary electrical power is. Analysis indicated that this residual speed and vapour pressure may be enough to run coolant pumps for 45 seconds, reduces the difference between the failure of the external power and the emergency generator.
Steps to run the test – What happened at chernobyl
- The reactor was to be run at low power level between 700 MW and 800 MW.
- The steam-turbine generator had to be run at full speed.
- When these conditions were received, the supply of steam for the turbine generator was to stop.
- The turbine generator display was to be recorded to determine whether it could provide bridging power for coolant pumps until the emergency diesel generator was automatically indexed to start and provide power to the cooling pumps went.
- After reaching the normal operating speed and voltage of the emergency generator, the turbine generator will be allowed to continue freewheel.
What happened at chernobyl details
First the experiment was delayed by 10 hours. It was deplayed as there was request from the controller of the electricity grid in Kiev. He requested the reactor operator to keep supplying electricity to enable demand to be met.
As scheduled experiment was delayed . Anatoly Dyatlov and other officials decided to carry on experiment during night. At night there was change of shift personnel. Night shift personnel was not experienced enough to test this experiment. Without this delay, the test would have been conducted during `day shift’.
This delay was first violation of safety standards then there was a series of violation of many safety violation during test. It was also reported that when shift operators tried to follow safety precautions they were verbally threatened by Anatoly Dyatlov. As Anatoly Dyatlov want to conduct this experiment desperately. Anatoly Dyatlov overlooked these safety precaution violations thinking that if anything goes beyond his control he cloud abort it by pressing emergency shutdown button (AZ 5).
- Non-routine operation of the reactor.
- Violation of operating regulations, including the removal of most of the control rods.
- Positive void coefficient characteristic of the reactor.
- Apparent lack of knowledge by the station staff of the characteristics of the reactor.
- Inadequate control rod design.
Result – What happened at chernobyl
Some 8 of the 140 tones of fuel, which contained plutonium and other highly radioactive materials (fission products), were ejected from the reactor along with a portion of the graphite moderator, which was also radioactive. These materials were scattered around the site. In addition, caesium and iodine vapours were released both by the explosion and during the subsequent fire.
Aftermath – What happened at chernobyl
there was a massive fire at Chernobyl nuclear power plant. Radioactive radiation spread around Pripyat city and later to wider area. Many people died within months of this disaster due radiation. people got cancer and other disease because of radiation.
Chernobyl and Valery Legasov
Valery Legasov was the First Deputy Director of the Kurchatov Institute of Atomic Energy. He was appointed member of the government commission formed to investigate the causes of the disaster and to plan the mitigation of its consequences.
He took the most important decisions to avoid repeat accidents and informed the government of the situation in the disaster area. He did not hesitate to speak to his fellow scientists and to the press about the safety risks of the destroyed plant and insisted on the immediate evacuation of the entire population of the city of Pripyat nearby.
In his he report displayed a depth of analysis and honesty in discussing the extent and consequences of the tragedy. He find out the flaw in designs of control rods. He reported that tip of the control rods was made of graphite. He told that when control rod started to move down from its uppermost position, they cause an increase in reactivity because their tips have graphite.