Transcript Argentina

International Conference on Management of Spent Fuel from Nuclear Power
Reactors, Vienna, 31 May - 4 June 2010
Operating Experience and Condition
Assessment of Spent Fuel Dry Storage Silos
and Spent Fuel Pool at Embalse NPP
Anibal Barrera
Life Extension Project
Embalse NPP.
CONTENTS

Spent Fuel Dry Storage Silos at Embalse NPP

In Service Inspection Program (ISI)

Condition Assessment
◦ Degradation mechanism
◦ Evaluation procedures

Conclusions and future tasks

Spent Fuel Pool
Spent Fuel Dry Storage Silos at Embalse NPP
19901991
19921993
Design
– Mock
up
80
2001
2002
2003
40
• 248 SILOS
• 133920 Fuel Bundles
• 2013 – Refurbishment Outage
2004
2005
64
2006
2007
2008
32
2009
2010
2011
32
Spent Fuel Dry Storage Silos at Embalse NPP
Spent Fuel Dry Storage Silos at Embalse NPP

Concrete
 Type II Portland cement
 f`c = 21 MPa
 Density = 2400 kg/m3

Reinforcement
 Fy = 420 MPa (Grade 60)

Steel Liner
 F 26 (ASTM A -36)
In Service Inspection Program (ISI)
Internal Moisture – Pressure air cleaning
Aerosols and noble gases detection
External Radiation Monitoring
X-rays surface examination – contact dose rate
Visual inspection, Corrosion analysis and
thickness measurement
Carbon Steel Corrosion
Containment Barrier
Integrity
Mock up with baskets
and metallic samples
Degradation mechanism - Evaluation procedures
Mechanism
Material
Manifestation
E. Procedure
Sulphate attack
Concrete
Volume Change/
Cracking
Visual Insp –
Petrographic A.
Carbonation
Concrete
Carbon Steel
Vulnerable to corrosion
Petrographic A
Carbonation depth
m.
CementAggregate
reaction
Concrete
Volume Change /
Cracking
Visual Insp –
Petrographic A.
Thermal Exposure Concrete
Cracking / Spalling
Visual Insp –
Petrographic A.
Irradiation
Concrete
/C. steel
Volume Change/
Cracking
Petrographic A.
Shrinkage
Concrete
Volume Change/
Cracking
Visual Insp.
Corrosion
C. Steel
Concrete Cracking –
Section/capacity loss
Visual Insp. –
Electrical potential
measurement
Conclusions

ISI tasks

New ISI Program
◦ Periodic Visual inspection
◦ Non destructive testing
Steel Corrosion
Crack Survey
Ultrasonic P.V.
◦ Destructive Testing
c. quality – calibration
NDT – Petrographic examination
SPENT FUEL POOL
LINER SYSTEM
1 - Amercoat90 (6 mil)
2 - Amercoat90 (6 mil)
3 - Amercoat90 0.15 mm
(6 mil)
CONCRETE
4 - Fiber-Glass Cloth with
Amercoat90 0.23 mm (~9
mil)
5 - Sand Filled Epoxy
Grout 1.6 - 3.2 mm (62.5 –
125 mil)
SUMMARY



No evidence of sign of leakage in external surfaces.
No evidence of leakage in the Spent fuel Pool Under drainage
System
Bubbles in liner were found – Temperature and irradiation
PREVENTIVE
MAINTENANCE
EPOXY
UNDERWATER
COATING
Thank you for your attention!