ML113050632
| ML113050632 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 10/26/2011 |
| From: | Howe K, Leavitt J, Sande T, Zigler G ALION Science & Technology Corp, Univ of New Mexico |
| To: | Balwant Singal Plant Licensing Branch IV |
| Singal, B K, NRR/DORL, 301-415-301 | |
| Shared Package | |
| ML113050615 | List: |
| References | |
| TAC ME5358, GSI-191, TAC ME5359 | |
| Download: ML113050632 (27) | |
Text
Risk Informing STP GSI-191 Chemical Effects Risk Informed GSI-191 Resolution Tuesday, November 1 Public Meeting with STP Nuclear Operating Company 1
Timothy D. Sande Gilbert L. Zigler Dr. Kerry J. Howe Janet J. Leavitt 11/1/11 Pre-Licensing Meeting
Outline Risk Informed GSI-191
- Meeting Objective
- Purpose of Chemical Effects Program
- Significant/Insignificant Contributors
- STP Parameters 11/1/11 Pre-Licensing Meeting 2
- STP Parameters
- Previous Tests Relevant to STP
- Preliminary Ideas for Testing
- Preliminary Ideas for Risk Informed Application
- Conclusions
Meeting Objective Risk Informed GSI-191
- Present the STP risk informed chemical effects approach to the NRC
- Obtain NRC comments prior to developing an initial test plan 11/1/11 Pre-Licensing Meeting 3
an initial test plan
Risk Informed GSI-191
- Fully understand physical and chemical phenomenon related to chemical effects at STP through research, testing, and modeling
- Develop an analytical model for chemical Goals of Risk Informed Chemical Effects Program 11/1/11 Pre-Licensing Meeting 4
y precipitate formation that can be implemented in CASA Grande
- Develop an algorithm for chemical effects head loss that can be implemented in CASA Grande
- Validate models with prototypical testing
Significant Contributors Risk Informed GSI-191
- Time
- Buffer
- pH
- Temperature
- Concrete Area
- Corrosion
- Dissolution
- Inhibition 11/1/11 Pre-Licensing Meeting 5
- Temperature
- Pool Volume
- Insulation Types
- Insulation Quantities
- Aluminum Area
- Inhibition
- Solubility Limits
- Kinetics
- Precipitate Types
- Precipitate Properties
Significant Contributors Risk Informed GSI-191
- Copper Area
- Lead Area
- Acid Formation
- HX Temperature Drop
- Retrograde Solubility 11/1/11 Pre-Licensing Meeting 6
- Acid Formation
- Concrete Aging
- RCS Chemistry
- RWST Chemistry
Insignificant Contributors Risk Informed GSI-191
- Carbon Steel
- Galvanized Steel
- Organic Material 11/1/11 Pre-Licensing Meeting 7
- Organic Material
- RCS Crud
- Radiolysis Products
- Biological Effects
STP Parameters Risk Informed GSI-191
- Buffer: TSP
- Nominal pH: ~7.6
- LBLOCA Containment Temperature: 260°F max to 120°F at 30 days 11/1/11 Pre-Licensing Meeting 8
to 120 F at 30 days
- LBLOCA Pool Temperature: 267°F max to 126°F at 30 days
- Pool Volume: 31,431 ft3 min, 89,350 ft3 max
- Nominal Spray Duration: 12 hr
STP Parameters Risk Informed GSI-191
6 ppm Silica 11/1/11 Pre-Licensing Meeting 9
- Pool Chemistry: 2,372 - 2,878 ppm boron
- Insulation: Nukon, Microtherm (penetrations), SS RMI (reactor cavity)
- Coatings: Epoxy, IOZ, Polymide, Alkyd, Enamel
- Nominal Aluminum Area: 5,567 ft2
STP Time Dependent pH Risk Informed GSI-191 11/1/11 Pre-Licensing Meeting 10
STP Time Dependent Temperature Risk Informed GSI-191 150°F at 3 5 days 11/1/11 Pre-Licensing Meeting 11 150 F at 3.5 days 140°F at 7 days
Previous Tests Relevant to STP Risk Informed GSI-191
- WCAP-16530 (single effects)
- WCAP-16785 (partially integrated effects)
- ICET Test 2 (integrated effects)
- Alion Vogtle Vuez Tests (integrated effects with 11/1/11 Pre-Licensing Meeting 12
- Alion Vogtle Vuez Tests (integrated effects with head loss)
- Alion Vogtle and Calvert Cliffs High Temperature Vertical Loop (HTVL) Tests (aluminum solubility)
STP WCAP-16530 Prediction Risk Informed GSI-191 Material Released Quantity (kg)
Calcium*
63.06 Silicon 208.85 Aluminum 82.92 11/1/11 Pre-Licensing Meeting 13 Precipitate Quantity (kg)
Sodium Aluminum Silicate 649.5 Aluminum Oxyhydroxide 35.7 Calcium Phosphate*
162.7
- Includes marinite source that is no longer in containment
STP WCAP-16785 Prediction Risk Informed GSI-191 Refinement Aluminum (ppm)
NaAlSi3O8 (kg)
AlOOH (kg)
Ca3(PO4)2 (kg)
Base Case 82.9 649.5 35.7 162.7 Silicon Inhibition 18.3 177.4 0.0 162.7 Phosphate Inhibition 69.4 649.5 5.6 162.7 11/1/11 Pre-Licensing Meeting 14 Solubility Limits 82.9 0.0 0.0 162.7
ICET Test Overview Risk Informed GSI-191 ICET Test Number Controlling pH buffer system Insulation (%)
Measured pH Chemical byproducts Visible at test temperature Visible upon cooling Fiberglass Cal-Sil 1
Borate (NaOH) 100 0
9.3 - 9.5 No Yes 2
Phosphate (TSP) 100 0
7.1 - 7.4 No No 3
Phosphate (TSP) 20 80 7.3 - 8.1 Yes, only during first few hours No 11/1/11 Pre-Licensing Meeting 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br /> 4
Borate (NaOH) 20 80 9.5 - 9.9 No No 5
Borate (Borax) 100 0
8.2 - 8.5 No Yes Test Duration: 30 days Test Temperature: 140°F Spray Duration: 4 hr Water Chemistry: Boron, lithium hydroxide, hydrochloric acid
Comparison to ICET Test 2 Inputs Risk Informed GSI-191 Material Type STP Quantities*
Ratio of STP Quantities to Max Pool Volume Ratio of ICET Test 2 Quantities to Tank Volume Ratio ICET/STP Aluminum submerged 700 ft2 0.007834 ft2/ft3 0.179 ft2/ft3 22.8 Aluminum exposed to spray 6300 ft2 0.070509 ft2/ft3 3.34 ft2/ft3 47.4 11/1/11 Pre-Licensing Meeting 16 Fiberglass insulation submerged 2385.1 ft3 0.026694 ft3/ft3 0.103 ft3/ft3 3.9 Marinite insulation submerged 15.2 ft3 0.00017 ft3/ft3 0.0 Microtherm insulation submerged 1.8 ft3 2.01E-05 ft3/ft3 0.0 Concrete submerged 5700 ft2 0.063794 ft2/ft3 0.015 ft3/ft3 0.2
- Quantities are taken from conservative inputs used in STP WCAP calculation, marinite removed, concrete only exposed to spray, etc.
ICET Test Results Risk Informed GSI-191 100 150 200 250 300 350 400 450 minum concentration (mg/L)
Test 1 unfiltered Test 1 filtered 20 30 40 50 60 70 80 minum concentration (mg/L)
Test 5 unfiltered Test 5 filtered 11/1/11 Pre-Licensing Meeting 17 0
50 0
10 20 30 Alum Time (days)
(a) 0 10 0
10 20 30 Alum Time (days)
(b)
Aluminum concentration below detection limit for Tests 2, 3, 4 Aluminum concentration leveled off over time for Tests 1, 5 Inverse trend between aluminum and silicon concentrations
Alion Vogtle Vuez Test Results Risk Informed GSI-191
- Minimal aluminum in solution
- No precipitates observed
- Head loss increased
~1 5x over 30 days 11/1/11 Pre-Licensing Meeting 18
~1.5x over 30 days, possibly due to effect of fiber bed dissolution (NUREG/CR-6808)
Increasing head loss due to Nukon dissolution (reproduced from NUREG/CR-6808 Figure 7-23)
Alion Vogtle and Calvert Cliffs HTVL Tests Risk Informed GSI-191 Vogtle
- Buffer: TSP
- Aluminum: 4 ppm
- Silica: 26 ppm Calvert Cliffs
- Buffer: NaTB
- Aluminum: 10 ppm
- Silica: 60 ppm 11/1/11 Pre-Licensing Meeting 19 pp
- pH: 7.6 - 7.8
- Results: No precipitation at temperatures as low as 128°F pp
- pH: 7.4
- Results: No precipitation at temperatures as low as 60°F
Preliminary Ideas for Testing Risk Informed GSI-191
- Perform integrated tests to determine material corrosion/dissolution/release rates and characterize precipitates in order to develop thermodynamics and kinetics models 11/1/11 Pre-Licensing Meeting 20
- Perform benchtop or autoclave tests to further develop database for models
- Perform HTVL tests with replicated precipitates and varying debris loads to develop a chemical effects head loss algorithm
Test Characterization of Precipitates Risk Informed GSI-191
- VUEZ tests indicate precipitates form as crystals, with nucleation on fiberglass fibers, 11/1/11 Pre-Licensing Meeting 21 rather than amorphous precipitates forming in the pool as predicted by WCAP-16530
Preliminary Ideas for Application to Risk Informed Analysis Risk Informed GSI-191
- Use thermodynamics (and if possible) kinetics models to develop a chemical module for CASA Grande that can be used to calculate chemical precipitate types and quantities for any 11/1/11 Pre-Licensing Meeting 22 combination of parameters applicable to STP
- Develop a chemical effects head loss algorithm that can be incorporated in the head loss module for CASA Grande that is applicable to the ranges of chemical and non-chemical debris loads at STP
Thermodynamics Modeling Risk Informed GSI-191 11/1/11 Pre-Licensing Meeting 23 0.1 1
10 100 1000 40 60 80 100 120 140 160 180 200 220 Solubility Limit for Aluminum (mg/L)
Temperature (F) pH = 7.0 pH = 7.5
Risk Informed GSI-191
- Particulate Chemical Precipitate:
- NUREG/CR-6224 Head Loss Correlation
- Chemical particulate modeled as other particulates, i.e., surface to volume ratio and density Chemical Head Loss Modeling 11/1/11 Pre-Licensing Meeting 24
- Amorphous Chemical Precipitate:
- Develop a bump-up factor algorithm for low amorphous chemical precipitate to fiber loads
- Interpolate WCAP-16530 head loss testing results
Risk Informed GSI-191
- Perform an Integrated 30 day test
- Realistic simulation of STP conditions:
- Temperature time history
- Materials exposed to spray Validation of Chemical Precipitate Model 11/1/11 Pre-Licensing Meeting 25
- Submerged material and debris
- Flow through a fiber bed
- Fluid analysis
- Weight loss measurements
- SEM of fiber bed
Validation of Chemical Head Loss Model Risk Informed GSI-191
- Perform Vertical Head Loss tests with chemical particulate simulant
- Compare Vertical Head Loss test results with NUREG/CR-6224 calculations 11/1/11 Pre-Licensing Meeting 26
- Wide range of eta (particulate to fiber weight ratio)
- Wide range of debris bed thickness
Conclusions Risk Informed GSI-191
- Currently available data indicates that chemical effects at STP is far less severe than predicted by the standard WCAP-16530 methodology
- A combination of testing and modeling can be 11/1/11 Pre-Licensing Meeting 27 g
g used to develop a realistic prediction of chemical effects for STP
- A chemical module and modified head loss module will need to be implemented into CASA Grande for evaluation of full range of scenarios