ML092321080
| ML092321080 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 08/20/2009 |
| From: | Farideh Saba Plant Licensing Branch II |
| To: | Progress Energy Co |
| References | |
| Download: ML092321080 (20) | |
Text
Brunswick Units 1 and 2 MELLLA+
I l
t ti Implementation August 19 2009 August 19, 2009 Eric Geyer Bill Murray John Siphers
Agenda Introduction and objectives MELLLA+ benefits for Brunswick (BSEP)
Fuel and plant licensing analysis strategy Thermal hydraulic stability solution Thermal hydraulic stability solution ATWS analysis and mitigation Fuel design Fuel design Schedule Questions and answers 2
Introduction and objectives MELLLA+ overview 110 0 120.0 Brunswick MELLLA+ with Representative EO-III NTSP Channel Exclusion Region Scram APRM STP Scram NTSP 80 0 90.0 100.0 110.0 APRM STP Rod Block NTSP EO-III Channel Exclusion 60.0 70.0 80.0
% Power MELLL Line EO-III Channel Exclusion and NC Line Scram MELLLA+ Line SPT AL Line 30.0 40.0 50.0 Scram Avoidance Region (Immediate Exit)
Scram BSP Region 0.0 10.0 20.0 0 0 7 7 15 4 23 1 30 8 38 5 46 2 53 9 61 6 69 3 77 0 84 7 92 4 Mlbs/hr Core Flow OPRM Enabled Region 3
0.0 7.7 15.4 23.1 30.8 38.5 46.2 53.9 61.6 69.3 77.0 84.7 92.4 Mlbs/hr Core Flow 0 10 20 30 40 50 60 70 80 90 100 110 120 % Core Flow
Introduction and objectives BSEP MELLLA+ licensing progress to date Nov 2002: BSEP MELLLA+ LAR submitted Significant NRC review completed; BSEP RAI responses:
May 2003 Moisture carryover FAC Jun 2003, Oct 2003 Vessel fluence Jun 2003, Oct 2003 Vessel fluence Jul 2003 SLO APRM STP scram Sep 2003 ATWS response N
2003 H
f i i Nov 2003 Human factors, operator training Apr 2004, Mar 2005 Irradiated stress corrosion cracking Aug 2005: MELLLA+ LAR withdrawn Aug 2005: MELLLA LAR withdrawn Intent to resubmit at later date as soon as practical Pending resolution of concerns with supporting generic LTRs 4
Introduction and objectives Progress toward LAR readiness BSEP fuel supplier change approved J l 2007 ANP 2638 AREVA EPU th d li bilit Jul 2007:
ANP-2638 AREVA EPU methods applicability Mar 2008:
BSEP ATRIUM-10 reload Supporting generic LTRs approved Supporting generic LTRs approved Sep 2007:
NEDC-33006 GEH generic MELLLA+ for GE14 Jan 2008:
NEDC-33173 GEH methods for GE14 M
2008 ANP 10262 AREVA EO III S bili May 2008:
ANP-10262 AREVA EO-III Stability Objectives Provide complete, efficient LAR that leverages past work Provide complete, efficient LAR that leverages past work Reduce challenges to reactivity management and fuel integrity Maintain and improve safety margins Improve reactivity management 5
MELLLA+ benefits for BSEP Reactivity can be controlled with flow or control rods MELLLA+ expands flow window from 5.5% to 19.5%
MELLLA requires ~75% more rod movement than MELLLA+
C t
l d
t h ll Control rod movement challenges:
Reactivity management (2007 INPO Area For Improvement)
Fuel integrity (2008 INPO Recommendation)
Fuel integrity (2008 INPO Recommendation)
MELLLA+ improves reactivity management and fuel integrity Cost savings do not support MELLLA+ implementation Cost savings do not support MELLLA+ implementation Analyses do not support significant fuel utilization improvement Reduced pump power provides only small generation increase Reduced pump power provides only small generation increase 6
MELLLA+ benefits for BSEP 8%
10%
(Percent) 4%
6%
ntrol Rod Desnity 0%
2%
Con 105%
ed) 95%
100%
w (Percent Rate 85%
90%
0 5
10 15 20 Core Flo 7
Cycle Exposure (GWd/MtU)
MELLLA+ benefits for BSEP Parameter MELLLA Cycle Avg / Cycle Limiting MELLLA+
Cycle Avg / Cycle Limiting y
g y
g y
g y
g Core flow 101.5% / 99.0%
93.1% / 86.0%
Core max radial peak 1.35 / 1.46 1.33 / 1.38 CPR margin 11 9% / 6 8%
8 9% / 5 3%
CPR margin 11.9% / 6.8%
8.9% / 5.3%
Core avg void 46.4% / 50.4%
47.9% / 52.2%
Core max exit void 84.3% / 87.7%
85.4% / 87.9%
LHGR margin 19.3% / 10.1%
17.9% / 11.1%
MAPRAT margin 23.7% / 13.4%
22.9% / 16.7%
Inlet subcooling 21.6 Btu/lb / NA 23.9 Btu/lb / NA Inlet subcooling 21.6 Btu/lb / NA 23.9 Btu/lb / NA
- Radial peaking and excess CPR margin exchanged for reduced flow
- Core performance margins maintained 8
Fuel and plant licensing analysis strategy Generic GEH M+ LTR process (NEDC-33006PA) will address:
Non fuel impacts Non-fuel impacts Long term ATWS and ATWS instability for GE14 fuel AREVA methodologies and analyses will address:
Fuel, core design, COLR fuel limits ATWS overpressure GE14 ATWS analysis applicability to AREVA fuel Methods applicability to MELLLA+
Progress Energy will address:
Integration of GEH and AREVA analyses Integration of GEH and AREVA analyses APRM and Enhanced Option III set points Risk evaluation, EPG/SAGs, operator training Plant modifications to mitigate ATWS Plant modifications to mitigate ATWS Stability scram activation 9
Fuel and plant licensing analysis strategy Preliminary Technical Specification changes TLO APRM flow biased STP scram line (3.3.1.1.2b)
Scram margin: expansion for M+ region; reduction for EO-III stability solution
Scram margin: expansion for M+ region; reduction for EO III stability solution
Corresponding changes in flow biased rod block
Existing AL-AV-NTSP set-point margins maintained Define MELLLA+ region add EO-III to COLR methods (5 6 5)
Define MELLLA+ region, add EO-III to COLR methods (5.6.5)
New equipment OOS LCO actions (various TSs)
SRVOOS (if required), SLO and OPRM inoperable E it MELLLA i
ithi 12 h f
di ll d
diti
Exit MELLLA+ region within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for disallowed condition OPRM inoperable
Implement manual BSP regions in COLR (no change)
Exit MELLLA+ region within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />; OPRM OOS or reduced FWT (new)
APRM scram natural circ line protection above BSP scram region (new protection) 1 SLCS pump OOS
Exit MELLLA+ region within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (new)
Shutdown in 7 days (no change) 10
Thermal hydraulic stability solution Enhanced Option III TLO APRM Scram 110 120 MELLLA+ APRM SPT Scram Reduction Enhanced Option III ChannelExclusion 80 90 100 110
(%)
Enhanced Option III Channel Exclusion Stability Protection Trip (SPT) Reduction 50 60 70 ated NTSP Power 20 30 40 Estima 0
10 0
10 20 30 40 50 60 70 80 90 100 110 120 Drive Flow (%)
11 EO-III APRM STP Scram EO-III APRM STP RB
Thermal hydraulic stability solution Power flow map 110 0 120.0 Brunswick MELLLA+ with Representative EO-III NTSP Channel Exclusion Region Scram APRM STP Scram NTSP 80 0 90.0 100.0 110.0 APRM STP Rod Block NTSP EO-III Channel Exclusion 60.0 70.0 80.0
% Power MELLL Line EO-III Channel Exclusion and NC Line Scram MELLLA+ Line SPT AL Line 30.0 40.0 50.0 Scram Avoidance Region (Immediate Exit)
Scram BSP Region 0.0 10.0 20.0 0 0 7 7 15 4 23 1 30 8 38 5 46 2 53 9 61 6 69 3 77 0 84 7 92 4 Mlbs/hr Core Flow OPRM Enabled Region 12 0.0 7.7 15.4 23.1 30.8 38.5 46.2 53.9 61.6 69.3 77.0 84.7 92.4 Mlbs/hr Core Flow 0 10 20 30 40 50 60 70 80 90 100 110 120 % Core Flow
ATWS analysis and mitigation Long term response BSEP EPU increased SLCS B10 enrichment to 47 w/o ATWS rule compliance basis remains two pumps but ATWS rule compliance basis remains two pumps, but Single pump meets ATWS rule boron injection rate requirement EPU risk assessment and current PSA model credit pump redundancy Long term ATWS MELLLA+ margin improvement will be demonstrated with GE14 ODYN analyses MELLLA+ rod line intercepts NC line post 2RPT ~20% higher in power Faster B10 injection reduces heat load (HSBW injected faster)
BSEP can increase SLCS B10 enrichment by up to a factor of 2 Potential to offset MELLLA+ heat load increase clearly sufficient No loss of margin with MELLLA+; no increase in risk with single SLCS pump AREVA fuel applicability to be dispositioned similar to BSEP AREVA AREVA fuel applicability to be dispositioned similar to BSEP AREVA fuel transition 13
ATWS analysis and mitigation Post depressurization NEDC-33006P Generic M+ LTR and SER: Best estimate TRACG or equivalent analysis of post depressurization ATWS TRACG or equivalent analysis of post depressurization ATWS required if HSBW not injected before HCTL reached BSEP has potential to inject HSBW before HCTL Increase SLCS B10 enrichment (x2)
Credit both SLCS pumps (x2)
New TS LCO action to exit MELLLA+ if 1 SLCS pump OOS New TS LCO action to exit MELLLA if 1 SLCS pump OOS Applicability of GE14 analysis to AREVA fuel will be dispositioned Substantial physical safety improvement Simplifies analysis Simplifies NRC review NRC feedback critical 14
ATWS analysis and mitigation Overpressure and instability ATWS instability S
h l
t d
t t
h i
i f
Same approach as long term; demonstrate change in margin for GE14 core with increased B10 injection rate B10 injection rate increase expected to provide some mitigation even with shorter event timing than long term containment heating Applicability to AREVA fuel to be addressed by disposition NRC feedback critical ATWS overpressure mitigation MG set replacement with adjustable speed drive improves 2RPT coastdown rate coastdown rate SRVOOS support for MELLLA+ to be evaluated Cycle specific AREVA overpressure analysis 15
Fuel design ATRIUM-10XM (A10XM)
MELLLA+ LAR to be based on A10XM if timing and reviews support A10XM requires adding two COLR methodologies to TS A10XM requires adding two COLR methodologies to TS ACE CPR correlation and RODEX4 fuel rod TM methodology LAR will demonstrate SER compliance Generically approved; no sample problem A10XM LAR separate from MELLLA+
Separate submittal preceding MELLLA+
A10XM approval (both Units) preceding MELLLA+ approval MELLLA+ LAR sample problem and cycle application B2C20 reload analysis report sample problem; first Unit 2 A10XM reload B2C20 reload analysis report sample problem; first Unit 2 A10XM reload B1C19 reload analysis report cycle specific application; first Unit1 A10XM reload and MELLLA+
16
Fuel design ATRIUM-10XM fuel cycle operation Parameter MELLLA+ A10 Cycle Avg / Cycle Limiting MELLLA+ A10XM Cycle Avg / Cycle Limiting y
g y
g y
g y
g Core flow 93.1% / 86.0%
91.4% / 85.7%
Core max radial peak 1.33 / 1.38 1.39 / 1.47 CPR margin 8 9% / 5 3%
14 8% / 5 0%
CPR margin 8.9% / 5.3%
14.8% / 5.0%
Core avg void 47.9% / 52.2%
47.7% / 52.9%
Core max exit void 85.4% / 87.9%
87.5% / 90.0%
LHGR margin 17.9% / 11.1%
13.7% / 7.3%
MAPRAT margin 22.9% / 16.7%
22.9% / 16.4%
Inlet subcooling 23.9 Btu/lb / NA 24.2 Btu/lb / NA Inlet subcooling 23.9 Btu/lb / NA 24.2 Btu/lb / NA
- Improved CPR margin supports radial peaking increase and reduced flow
- Core performance margins maintained 17
Schedule A10XM LAR; ACE and RODEX (both Units)
Spring 2010 MELLLA+ LAR submittal (both Units)
Fall 2010 MELLLA+ LAR submittal (both Units)
Fall 2010 B2C20 sample problem with A10XM ATRIUM-10XM approval (both Units)
Spring 2011 First ATRIUM-10XM reload (B2C20)
Spring 2011 B1C19 cycle specific application Fall 2011 First MELLLA+ cycle with A10XM y
MELLLA+ approval (both Units)
Spring 2012 NRC f db k
iti l
NRC feedback critical 18
Summary Reduce challenges to reactivity management R d h ll t
f l i t it Reduce challenges to fuel integrity Maintain and improve safety margins Efficient LAR approach Efficient LAR approach Leverage past work Address fuel design 19
BSEP Units 1 and 2 MELLLA+ Implementation Q
ti
?
Questions?
20