task 1.5.4 containment assessment
DESCRIPTION
Task 1.5.4 Containment Assessment. IP-EUROTRANS DOMAIN 1 Design WP 1.5 Safety Assessment of the Transmutation System Design. Fission product confinement and control Protection against external events Biological shielding. Containment System Safety Functions. - PowerPoint PPT PresentationTRANSCRIPT
Sheet 1November 13th-14th, 2007, Madrid
Task 1.5.4 Containment Assessment
IP-EUROTRANSDOMAIN 1 Design WP 1.5
Safety Assessment of the Transmutation System Design
IP-EUROTRANSDOMAIN 1 Design WP 1.5
Safety Assessment of the Transmutation System Design
Sheet 2November 13th-14th, 2007, Madrid
• Fission product confinement and control
• Protection against external events
• Biological shielding
Containment System Safety Functions
Sheet 3November 13th-14th, 2007, Madrid
• Limitation of radionuclide releases
• Fission and spallation product removal mechanisms
• Containment isolation
• Leak tightness
• Containment integrity
• Structural behaviour
• Energy management system
Fission product confinement and control
Sheet 4November 13th-14th, 2007, Madrid
• Representative events selection DBC/DEC
– Definition of mass/energy releases
– Source term definition
• Definition of fuel damage extension
• Dose calculation. Different hypothesis
• Comparison with acceptance criteria
• Containment integrity requirements
Containment Requirements
Sheet 5November 13th-14th, 2007, Madrid
• DBC
– Primary HX tube ruptures
– Secondary coolant pipe breaks
– Cover gas system pipe break
• DEC
– Fuel sub-assembly blockage
Representative events
Sheet 6November 13th-14th, 2007, Madrid
DBC conditions
DBCFUEL DAMAGE
SOURCE TERM MASS/ENERGY RELEASE
DBC1 No fuel damage Normal operation N/A
DBC2 No fuel damage Normal operation Limited (Small leakages)
DBC3No fuel damage except test pins
Normal operation + test pins Large leakages/HX tube ruptures
DBC4Localised damage
Extension of damage to be defined ¿10%? Total SCS dumping
Sheet 7November 13th-14th, 2007, Madrid
DEC conditions
DECFUEL DAMAGE
SOURCE TERM MASS/ENERGY RELEASE
Complex sequences
Localised damage
Extension of damage to be defined ¿10%?
No DEC associated to significant mass and energy releases to the containment
Severe accidents
Core damage/coolable inside vessel Core damage
No DEC associated to significant mass and energy releases to the containment
Sheet 8November 13th-14th, 2007, Madrid
Relevant conclussions
oHigh mass/energy release events not associated to DEC sequences
oThis allows to considering requirements for pressure relief separately from confinement requirements
oContainment pressure relief system through a filtered venting system
oDose calculations to show compliance with acceptance criteria
Sheet 9November 13th-14th, 2007, Madrid
• 10 % FUEL RODS FAILED (0.1 % during Normal Operation)
• EXCLUSION AREA BOUNDARY (EAB): 1000 m
• SOURCE TERM extrapolated from Superphenix MOX fuel
• LEAK RATE from containment: 1 % volume/day
• Acceptance criterion: DBC4 50 mSv (consequences have to be
assessed for a long period – 50 years)
Dose assessment
Sheet 10November 13th-14th, 2007, Madrid
Some credits that may be considered:
1. Po WALL DEPOSITION
2. Po TRAPPING (FILTERING SYSTEM)
3. Po NON-VOLATILITY (% Po non-evaporated)
4. I RELEASE-TO-CONTAINMENT FRACTION
5. Cs DEPOSITION, FILTERING OR ANY OTHER WAY OF REMOVAL
Credits
Sheet 11November 13th-14th, 2007, Madrid
CreditCase
0 1 1b 2 2b 3
Po trapping (%) 0 0 0 0 0 0
Po wall deposition (%) 0 0 0 0 0 0
Po non-volatility (%) 0 25 25 90 90 90
I fraction release 1 1 0,5 1 0,5 0,5
Cs deposition (%) 0 0 0 0 0 25
Sheet 12November 13th-14th, 2007, Madrid
Inhalation Dose
Dim(t)=A'(t)·FDC·/Q(t)
Calculation equations
Immersion Dose
Dih(t)=A'(t)·FDT·/Q(t)·BR
D(t): Dose after a given time t, [Sv]A’(t): Activity released from containment at a given time t, [Bq]FDC/FDT: Dose conversion factor for each radionuclide/Q(t): Offsite atmospheric dispersion factor, [s/m3]BR: Breathing rate, [m3/s]
Sheet 13November 13th-14th, 2007, Madrid
Results
Isotope
Dose after 1yr (mSv)
Case 0
Case 1
Case 1b
Case 2
Case 2b
Case 3
Po-210
35,84 3,62 3,62 1,98 1,98 1,98
I 6,50 6,50 1,09 6,50 1,09 1,09
Others*
16,24 16,24 16,24 16,24 16,24 3,11
TOTAL
58,58 26,36 20,95 24,72 19,31 6,18* Mostly due to Cs
Sheet 14November 13th-14th, 2007, Madrid
1
10
100
0 20 40 60 80 100 120 140
t (d)
Dos
e (m
Sv)
Cat. 4 Safety Principles (50 mSv)Case 0Case 1Case 1bCase 2Case 2bCase 3
Dose time-evolution for assessed cases
Sheet 15November 13th-14th, 2007, Madrid
Dose gets Safety Principles Limit for category 4 events (50 mSv) after 20 days in case 0
This limit has not been reached for any other cases during the 1st year
Preliminary conclusions
Sheet 16November 13th-14th, 2007, Madrid
• Update source term (which has been extrapolated from
Superphenix reactor) in order to obtain more realistic results
• Further considerations about Po and Hg should be taken
into account regarding chemical toxicity that have not been
considered in these radiological dose calculations
Objectives
Sheet 17November 13th-14th, 2007, Madrid
Subtasks definition
Source Term Behaviour
Subtask 1.5.4.2a Bounding definition of potential releases to the containment and its behaviour on the basis of the different source term information available from Work Package 1.5.3 and the above analyses
Subtask 1.5.4.2b Fission products and Polonium transport mechanism will also be evaluated.
Subtask 1.5.4.2c The potential dose to the operators and the environment from the above source terms will be calculated.
Subtask 1.5.4.2d Recommendations, if required, for radioactive and fission product removal will be analysed.
Sheet 18November 13th-14th, 2007, Madrid
Subtasks definition
Containment Requirements for the XT-ADS and EFIT Designs
Subtask 1.5.4.3a Evaluation of containment function performance requirements for both designs, based on the data gathered from the above activities and WP 1.2 results
Subtask 1.5.4.3b Evaluation of containment function taking into account the main features related to the following:•Limitation of radionuclide releases (confinement function)•Containment integrity
Subtask 1.5.4.3c Evaluation of other features such as protection against external hazards, HVAC/Filtering requirements or biological shielding
Subtask 1.5.4.3d Consideration of specific conditions that may be imposed on containment and confinement requirements
Sheet 19November 13th-14th, 2007, Madrid
Subtask Responsibilities
The Task Partners are: KTH, FZK and EA
The following split of responsibilities for the elaboration of Task 1.5.4 deliverables is proposed:• Subtask 1.5.4.1a FZK• Subtask 1.5.4.1b KTH• Subtask 1.5.4.1c KTH• Subtask 1.5.4.1d EA• Subtask 1.5.4.2a FZK/KTH• Subtask 1.5.4.2b FZK/KTH• Subtask 1.5.4.2c EA• Subtask 1.5.4.3a EA• Subtask 1.5.4.3b EA• Subtask 1.5.4.3c EA• Subtask 1.5.4.3d EA
Sheet 20November 13th-14th, 2007, Madrid
Budget
The assigned total budget allocation for Task 1.5.4 is as follows:
EA 4 m/m
FZK 4 m/m
KTH 4 m/m
Sheet 21November 13th-14th, 2007, Madrid
CONTENTS
1. INTRODUCTION AND PURPOSE
2. INTERNATIONAL GENERAL DESIGN CRITERIA FOR CONTAINMENT
3. GENERAL SAFETY CRITERIA. CONTAINMENT CRITERIA
3.1 DEFENCE-IN-DEPTH
3.2 SAFETY FUNCTIONS
3.3 LINES OF DEFENCE (LOD) METHODOLOGY
4. GENERAL FUNCTIONS OF THE CONTAINMENT
4.1 CONFINEMENT AND CONTROL OF RADIOACTIVE PRODUCTS
4.2 PROTECTION AGAINST EXTERNAL EVENTS
4.3 CONTAINMENT ACCESIBILITY
5. BARRIERS AGAINST THE RELEASE OF RADIOACTIVE PRODUCTS
5.1 BARRIERS AGAINST THE RELEASE OF RADIOACTIVE PRODUCTS FROM THE FUEL
5.2 BARRIERS AGAINST THE EMISSION OF RADIOACTIVE PRODUCTS FROM THE TARGET
6. DESIGN BASIS CONDITIONS. CONTAINMENT DESIGN REQUIREMENTS
6.1 DESIGN BASIS CONDITIONS. LBE-COOLED XADS DESIGN
6.2 DESIGN BASIS CONDITIONS. GAS-COOLED XADS DESIGN
7. DESIGN EXTENSION CONDITIONS. REQUIREMENTS FOR THE DESIGN OF THE CONTAINMENT
7.1 CONTAINMENT HEAT REMOVAL SYSTEMS
7.2 LBE-COOLED XADS DESIGN
7.3 GAS-COOLED XADS DESIGN
8. SUMMARY OF CONTAINMENT DESIGN REQUIREMENTS
8.1 CONTAINMENT GENERAL ARRANGEMENT
8.2 CONTAINMENT HEAT REMOVAL
8.3 CONTAINMENT LEAKTIGHTNESS
8.4 STRUCTURAL DESIGN
8.5 CONTAINMENT ISOLATION
8.6 RADIATION PROTECTION
9. PENDING ITEMS
10. REFERENCES
APPENDIX A TABLES
APPENDIX B GENERAL DESIGN CRITERIA FOR CONTAINMENT IN AMERICAN, GERMAN, IAEA AND EUR STANDARDS
B.1 CURRENT GERMAN CONTAINMENT FUNCTION-RELATED REGULATIONS
B.2 CURRENT USA CONTAINMENT FUNCTION-RELATED REGULATIONS
B.3 CURRENT EUROPEAN UNION REGULATORY CRITERIA
B.4 CURRENT INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA) CRITERIA
B.5 EUR CRITERIA RELATED TO CONTAINMENT FUNCTION
B.6 KEY CRITERIA