What had occurred in the first machine of the first nuclear plant in Tokyo Electric Power Company Fukushima after the earthquake?
Data, the driving diary of the nuclear reactor that Tokyo Electric Power Company opens to the public on the 16th, and, and, the situation is reproduced from measures etc. written on the whiteboard of the central control room that can look for the appearance to which it becomes tense immediately after the accident.
It is at 2:46PM, March 11th that the earthquake occurred.
It is described on the whiteboard of the central control room where the first machine is driven at the same time, "Succeed in the reactor automatic shutdown".
The dynamo for the emergency also starts automatically at the same time.
The appearance at that time has been left for paper that records the change in pressure in the nuclear reactor.
All valves of the piping connected by the reactor automatic shutdown outside the nuclear reactor are shut, it rises while pressure is usually driving, and the safety device that is called "Isolation condenser" moves by the automatic operation at 2:52PM after six minutes from the earthquake generation.
This is assumed to be pulling out the steam of the nuclear reactor, a return to water, and an automatically open with the device to pour water into the nuclear reactor again the valve to pour water.
However, this "Isolation condenser" had stopped around 3:00PM after only eight minutes.
In the operation procedure when the nuclear reactor that Tokyo Electric Power Company is providing stops, the temperature of water that cools the nuclear reactor is assumed to stop the isolation condenser to prevent the nuclear reactor being damaged when falling 55 times or more an hour.
In the data of the temperature of the nuclear reactor, the water temperature at 3:00PM fell from about 150 degrees and the reactor automatic shutdowns from 100 degrees by 100 degrees or more in about 15 minutes.
Therefore, Tokyo Electric Power Company is investigating in addition as "There is a possibility that the driving member stopped by hand power".
Abnormality occurs at 3:37PM after the 30 minutes.
It is a character of "SBO" in the central control room whiteboard.
It means "SBO" is abbreviation of "Station blackout", and all power supplies that the dynamo for the emergency besides the power supply from the outside was able also to use in the nuclear power plant including it were lost.
The first nuclear power plant in Fukushima had been just overcome by the tsunami in those days.
It is expected that it will become impossible to be flooded of the seawater pump of the dynamo for the emergency, and to use.
Neither cooling function for the emergency that needed the power supply as a result started, and the data of the water level became impossible to acquire everything the temperature, pressure, and it it, too.
It is at 6:18PM that the valve was opened again though the isolation condenser that stopped at 3:00PM moves to this even if there is originally no power supply.
After the tsunami had come, all functions to put water in the nuclear reactor were lost for about three hours.
However, the isolation condenser that was the last fort of the cooling function repeated the start and the stop afterwards.
The valve is shut only 15 minutes after reactivation.
Tokyo Electric Power Company is assuming that who neither close of the valve nor closed in the automatic operation is understood.
In addition, the reactivation secondarily was 9:30PM.
At this time, it is written that the steam that occurred when water is cooled with the isolation condenser was confirmed to the whiteboard.
The water level falls after 6:00AM of the 12th the next day, and the first machine has caused the explosion by the hydrogen that finally melted the fuel and is generated in the record that has been left though it doesn't understand whether this isolation condenser functioned finally at the time of when.
Data, the driving diary of the nuclear reactor that Tokyo Electric Power Company opens to the public on the 16th, and, and, the situation is reproduced from measures etc. written on the whiteboard of the central control room that can look for the appearance to which it becomes tense immediately after the accident.
It is at 2:46PM, March 11th that the earthquake occurred.
It is described on the whiteboard of the central control room where the first machine is driven at the same time, "Succeed in the reactor automatic shutdown".
The dynamo for the emergency also starts automatically at the same time.
The appearance at that time has been left for paper that records the change in pressure in the nuclear reactor.
All valves of the piping connected by the reactor automatic shutdown outside the nuclear reactor are shut, it rises while pressure is usually driving, and the safety device that is called "Isolation condenser" moves by the automatic operation at 2:52PM after six minutes from the earthquake generation.
This is assumed to be pulling out the steam of the nuclear reactor, a return to water, and an automatically open with the device to pour water into the nuclear reactor again the valve to pour water.
However, this "Isolation condenser" had stopped around 3:00PM after only eight minutes.
In the operation procedure when the nuclear reactor that Tokyo Electric Power Company is providing stops, the temperature of water that cools the nuclear reactor is assumed to stop the isolation condenser to prevent the nuclear reactor being damaged when falling 55 times or more an hour.
In the data of the temperature of the nuclear reactor, the water temperature at 3:00PM fell from about 150 degrees and the reactor automatic shutdowns from 100 degrees by 100 degrees or more in about 15 minutes.
Therefore, Tokyo Electric Power Company is investigating in addition as "There is a possibility that the driving member stopped by hand power".
Abnormality occurs at 3:37PM after the 30 minutes.
It is a character of "SBO" in the central control room whiteboard.
It means "SBO" is abbreviation of "Station blackout", and all power supplies that the dynamo for the emergency besides the power supply from the outside was able also to use in the nuclear power plant including it were lost.
The first nuclear power plant in Fukushima had been just overcome by the tsunami in those days.
It is expected that it will become impossible to be flooded of the seawater pump of the dynamo for the emergency, and to use.
Neither cooling function for the emergency that needed the power supply as a result started, and the data of the water level became impossible to acquire everything the temperature, pressure, and it it, too.
It is at 6:18PM that the valve was opened again though the isolation condenser that stopped at 3:00PM moves to this even if there is originally no power supply.
After the tsunami had come, all functions to put water in the nuclear reactor were lost for about three hours.
However, the isolation condenser that was the last fort of the cooling function repeated the start and the stop afterwards.
The valve is shut only 15 minutes after reactivation.
Tokyo Electric Power Company is assuming that who neither close of the valve nor closed in the automatic operation is understood.
In addition, the reactivation secondarily was 9:30PM.
At this time, it is written that the steam that occurred when water is cooled with the isolation condenser was confirmed to the whiteboard.
The water level falls after 6:00AM of the 12th the next day, and the first machine has caused the explosion by the hydrogen that finally melted the fuel and is generated in the record that has been left though it doesn't understand whether this isolation condenser functioned finally at the time of when.
