Japanese Prime Minister declared a "nuclear emergency" after a lot of reactors turned off by a powerful earthquake that hit the country.
Eleven reactors at four nuclear power plants automatically disconnected, but officials reported that the cooling system of one of the reactors have failed, or did not work correctly. According to Japanese law, an emergency must be declared if the cooling system has ceased to function.
In total, there are 55 reactors that provide about one-third of the country’s electricity. The report of Japan Atomic Industrial Forum said that Prime Minister Naoto Kan declared the emergency to the next "fast action", but "no release of radioactive substances" were found.
The reactor at the Fukushima Daiichi power plant, which has initiated an emergency alarm is a 40-year-old reactor 1, one of six in the area. Reactors 1, 2 and 3 are automatically disconnected when the amount of shaking the plant was 8.9 points, while reactors 4, 5 and 6 were not in working order, as they were shut down for a scheduled inspection. Water heating reactors Reactors (BWR) are among the most common projects that are widely used in the Japanese nuclear power plants.
Heat is produced nuclear reaction in the core, causing the boiling water and steam generation. Steam is used directly to control the turbine, whereupon it is cooled in the condenser and is converted back to water. Water is then pumped into the reactor core, completing the cycle. Even when the reactor is turned off and the nuclear fission stopped intense heat level remains needs dispersion as a function of the cooling mechanisms.
It is understood that the earthquake has stopped the supply of electricity to the power plant and auxiliary generators did not come into play when it happened. As a result, not all of the cooling system to function. According to the power plant operator Tokyo Electric Power Company, the reactor pressure rose after the cooling system was damaged by shaking.
Approximately 3,000 residents living within a radius of two kilometers from the power plant, 170 miles closer to the north-eastern part of Tokyo, was required to leave their homes because of the emergency and follow-up.
The representative of the World Nuclear Association (WNA) Jeremy Gordon said that the announcement of an emergency situation, it was a legal requirement and is not meant a real cause for concern. He said the country’s nuclear power plant in service for 45 years, and during that time also happened a lot of earthquakes.
According to Japanese law, nuclear emergency should be declared in the case of release of radiation, a dangerous level of water in the reactor, or if the cooling mechanisms are out of order. Japan Atomic Industrial Forum said it will continue to provide regular information on its Web site to keep people up to date on developments in Fukushima.
Original: BBC Translation: M. Potter