5. 福島核能電廠有緊急替代灌水途徑及灌水動力
福島核能電廠有緊急替代灌水途徑(淡水與海水)
– lines via fire extinguishing systems and condensate water
makeup systems from the filtrate tanks as the water sources
– lines via condensate water makeup systems from the condensate
storage tanks as the water sources
– TEPCO has built a switching facility in Unit 3 for injecting
seawater into the reactor via the residual heat removal sea water
system.
– Units 1 and 2 are not provided with such the facility because no
seawater lines lead into the reactor buildings of Units 1 and 2.
有灌水動力( 3 motor driven pump 與 1 diesel driven
pump )
有灌水程序書
– procedures for coolant injection using these lines during accidents
(severe accidents)
灌水途徑與動力可能在事故中受損
5
6. 6
福島核能電廠為何沒有及早執行爐心降壓灌水?
一號機與二號機灌水設備受損
三號機 ?呢
– Due to the total loss of AC power supply, however, difficulties arose in
assuring the air pressure for driving the SRV necessary for
depressurization and maintaining the excitation of the electromagnetic
valves in the air supply line, resulting in time-consuming
depressurization operations.
– in this accident, as an ad hoc applicable operation, water injection into
the reactor using a chemical fire engine that was present at the site was
attempted.
– Nevertheless, since the reactor pressure was higher than the pump
discharge pressure of the chemical fire engine, injection of freshwater
into the reactor was not available in a few cases.
– 非不為也,實不能也!
– 全黑時如何維持 SRV 之空氣壓力,為關鍵重點,建議以實證方式加以確認
19. 19
當 RCIC 失效後,反應器壓
力大幅上升
即使降壓成功,已經到灌水
的階段,反應器壓力仍可能
再度上升
– For unit 2, on March 14
around 18:00 due to the
problems including the air
pressure for driving SRV and
the maintaining excitation of
the solenoid valve of the air
supply line,the SRV was
seemed to be closed and the
reactor pressure increased.
SRV condition was unclear
after March 14 around 18:00
24. 影響圍阻體降壓之因素—閥無法開啟
Because of the total loss of the AC power supply, motor driven
valves had to be opened manually for the PCV venting
operations.
For operation of pneumatically-actuated valves, the
pressurized air required for operating such valves could not
be assured, and thus a temporary air compressor had to be
mounted to assure the pressurized air.
For such reasons, the facilities could not be operated in
accordance with the documented operation procedures for
severe accidents, which caused the PCV venting operation to
be delayed.
氣動閥與電動閥與爆破閥一路串接之方式 得檢討值
28. 附帶討論 2 :發生嚴重事故時,圍阻體排氣該不該排到煙囪
發生嚴重事故時,龍門核能電廠圍阻體排氣沒有排到煙囪
– Containment Overpressure Protection System (COPS)
which protects the containment by use of rupture disks
mounted in a line connecting the wetwell airspace to the
COPS vent which is located on top of the Reactor Building.
– Release from the wetwell airspace takes advantage of the
suppression pool scrubbing of radioactive aerosol and
particulates. Two isolation valves are also used to re-
establish containment integrity.