ID :
187911
Sat, 06/11/2011 - 18:07
Auther :
Shortlink :
https://oananews.org//node/187911
The shortlink copeid
TEPCO starts ventilating No. 2 reactor to lower radiation levels
TOKYO (Kyodo) - Tokyo Electric Power Co. said Saturday it began operating ventilation equipment with filters to absorb radioactive materials to reduce radiation levels inside the No. 2 reactor building of the crisis-hit Fukushima Daiichi nuclear power plant to pave the way for restoration work inside.
As earlier ventilation of steam at the plant is blamed for widely spreading radioactive substances outside, the government's nuclear safety agency is considering requiring that boiling-water reactors across Japan have steam-venting pipes equipped with filters to remove such toxic substances.
At the Fukushima plant's No. 2 reactor, highly radioactive materials and high humidity inside the building have prevented workers from entering the site to check measuring gauges and conduct piping work, hampering efforts by the utility to stabilize the reactor.
If airborne radioactive materials are sufficiently removed after running the equipment for three days, the utility known as TEPCO plans to open the doors of the reactor building and begin work inside the unit.
As in the case of three troubled reactors at the complex, steam inside a boiling-water reactor may be vented to prevent its containment vessel from cracking in the event internal pressure surges due to a loss of power source or coolant water.
But the type of reactors in Japan have had no filters, which are costly and pose a technical challenge to withstand high-pressure steam, as power utilities have failed to prepare for a serious accident, officials of the Nuclear and Industrial Safety Agency said.
According to the state-run Japan Nuclear Energy Safety Organization, nuclear power plants in such European countries as France and Sweden have filters to remove radioactive materials at their exhaust systems for venting steam, and the United States is considering a similar system.
As earlier ventilation of steam at the plant is blamed for widely spreading radioactive substances outside, the government's nuclear safety agency is considering requiring that boiling-water reactors across Japan have steam-venting pipes equipped with filters to remove such toxic substances.
At the Fukushima plant's No. 2 reactor, highly radioactive materials and high humidity inside the building have prevented workers from entering the site to check measuring gauges and conduct piping work, hampering efforts by the utility to stabilize the reactor.
If airborne radioactive materials are sufficiently removed after running the equipment for three days, the utility known as TEPCO plans to open the doors of the reactor building and begin work inside the unit.
As in the case of three troubled reactors at the complex, steam inside a boiling-water reactor may be vented to prevent its containment vessel from cracking in the event internal pressure surges due to a loss of power source or coolant water.
But the type of reactors in Japan have had no filters, which are costly and pose a technical challenge to withstand high-pressure steam, as power utilities have failed to prepare for a serious accident, officials of the Nuclear and Industrial Safety Agency said.
According to the state-run Japan Nuclear Energy Safety Organization, nuclear power plants in such European countries as France and Sweden have filters to remove radioactive materials at their exhaust systems for venting steam, and the United States is considering a similar system.
