View
4
Download
0
Category
Preview:
Citation preview
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc.
Fukushima Nuclear AccidentA TEPCO Nuclear Engineer’s Perspective
ASME—Forging a New NuclearSafety Construct Workshop
Washington, DCDecember 5th, 2012
Kenji TateiwaManager, Nuclear Power Programs
Tokyo Electric Power Company, Washington Officetateiwa.kenji@tepco.co.jp
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 2
Great East Japan Earthquake (GEJE)
http://archive.shinsai.yahoo.co.jp/
http://archive.shinsai.yahoo.co.jp/
http://archive.shinsai.yahoo.co.jp/Cruise Ship Stranded
Houses Swept Away
Largest earthquake/tsunami in recorded history of Japan20+ m tsunami run-up observed in
coast line spanning 200 km1st-ever case Gov’t Emergency
Disaster Response HQ was set up19,000 dead/missing
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 3
Impact of GEJE to TEPCO Facilities
Epicenter
52 GW
31 GW
Beforeearthquake
Shortly afterearthquake
Lost 40 % of power supply
capacityShutdown:
Nuclear power stations: 7 units Thermal power stations: 12 units Hydro power stations: 25 Substations: 8
Immediate Power outage: 4 million households(14% of TEPCO’s customer base)
Rolling blackout: 10 days in March 2011
Massive interruption of infrastructure (even in Tokyo area):
Public transportation Telecommunication Food/water supply
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 4
My Post-Accident Activities:International Communication
Translation of Press Releases (3/11/11@Tokyo-H/Q)
Photo by V.J.LUNA
Presentation to 15 Embassies in Tokyo (6/24/11@Delegation of EU to Japan)
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 5
My Post-Accident Activities:International Collaboration
IAEA Preliminary Mission (4/6/11@1F)
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 6
My Post-Accident Activities:International Collaboration (cont’d)
Preparation forIAEA Fact-Finding Mission(5/21/11@1F “Bedroom”)
IAEA Fact-Finding Mission(5/27/11@1F)
Mike Weightman(Head of UK-ONR)
Masao Yoshida(1F Plant Manager)
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 7
My Post-Accident Activities:International Collaboration (cont’d)
Discussion with INPO-Industry Support Team (8/19/11@2F)
“Nothing has been more important in my career than supporting TEPCO.”
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 8
Supervised operation wearing full-face mask.
Checked instrumentation in near-complete darkness.
Accident Response at 1F<Challenging Condition in Main Control Room>
Brought in heavy batteries to restore instrumentations.
Lack of:instrumentation, communication means, lighting, food, water, sleep, ...Increase in:radiation level, fatigue, fear, despair, ...
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 9
Accident Response at 1F<Containment Vessel Venting in Unit-1>
72AO
ボンベ
210MO ラプチャーディスク 排気筒
1AO
ボンベ
閉
閉
83AO
閉
閉90AO
0.549MPabsで破壊
RPV
D/W
RPVRPV
D/W
IA
IA
D/W最高使用圧力0.528MPabs
ベント実施圧力0.954MPabs
電磁弁
電磁弁
213AO
Remote operation unavailable due to SBO.
MO
AO
AO
AO
AO
MO
Exhaust stack
Rupture disc
Six men formed 3 “suicide squads” to manually open 2 valves in highly-radioactive area.
Core damage already occurred by this time.(3/12 9:04-9:30).
Venting required to
avoid catastrophic
failure.
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 10
Accident Response at 1F<Water Injection Into Reactors by Fire Trucks>
inoperable
standby
Shallow Draft Quay
Sea
Valve Pit Valve Pit Valve Pit Valve Pit
Fire Cistern
Fire Cistern
Fire Cistern
Fire CisternFire
Cistern
Fire trucks played critical role in injecting water into reactors and spent fuel pools.
24 fire trucks deployed. Fire brigade operated fire trucks amidst
high radiation and successive explosions.
Status as of 3/14/11
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 11
Overview of the 10-Unit Simultaneous Accidents
Date1F 2F
1 2 3 4 5 6 1 2 3 4
3/11
3/12
3/13
3/14
3/15
3/16-19
3/20
3/14 17:00
3/14 1:24RHR 3/14 7:13
RHR
3/14 15:42RHR
3/14 18:00
3/15 7:15
3/12 12:15
3/20 14:30
3/19 22:14RHR
3/12 8:13D/G-6B
3/22 10:35P/C-4D
3/22 10:36P/C-4D
3/20 15:46P/C-2C
3/20 15:46P/C-2C
3/19 5:00RHR
3/20 14:30
Station Blackout
Loss of Ultimate Heat Sink
Cold Shutdown
3/12 15:36 Unit 1 Explosion
3/15 6:00-6:10 Unit 4 Explosion
3/14 11:01 Unit 3 Explosion
3/11 15:27 1st Tsunami, 15:35 2nd Tsunami 3/11 15:22~ Tsunamis
Water Injection: NOHeat Removal: NO
Water Injection: YESHeat Removal: NO
Water Injection: YESHeat Removal: YES
All Rights Reserved ©2012 Tokyo Electric Power Company, Inc. 12
Voices from the Field
“In total darkness, I could hear the unearthly sound of SRV dumping steam into the torus. I stepped on the torus to open the S/C spray valve, and my rubber boot melted.”
“Radiation level in the main control room was increasing by 0.01 mSv every 3 seconds but I couldn’t leave—I felt this was the end of my life.”
“Unit 3 could explode anytime soon, but it was my turn to go to the main control room. I called my dad and asked him to take good care of my wife and kids should I die.”
Unit 1 Main Control Room
Torus Room
Recommended