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CHLE Update. STP October Team Lead Meeting 11/29/2012 Janet Leavitt, Ph.D. Overview. T2 LBLOCA Results Bench Top Experiments NRC Call. Corrosion/precipitation scenario. T2 LBLOCA. Objective Determine the mass of aluminum corrosion
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CHLE Update STP October Team Lead Meeting 11/29/2012 Janet Leavitt, Ph.D.
Overview • T2 LBLOCA Results • Bench Top Experiments • NRC Call
T2 LBLOCA • Objective • Determine the mass of aluminum corrosion • Evaluate possible effects of key corrosion and dissolution materials on head loss • Conditions • 15” Temperature profile • 6.5 hr spray • Standard Chemistry • Boric Acid, LiOH, TSP, HCL, HNO3 • Multiple Materials • Submerged zinc granules determined from 371 lbs of paint chips • Vapor and submerged STP aluminum scaffolding (90%/10%) • Submerged Fiber glass – columns and tank (41%/59%) • Submerged concrete
T2 LBLOCA Preliminary Results • SEM • Membranes • Scale • Coupons • ICP Analysis of Scale • XRD • XPS Temperature Profile Approach Velocity Differential Pressure pH Turbidity Select metal concentrations
Vapor Space Materials Pre-test Post-test
Submerged Materials • Pre-test Pre-test Post-test
Submerged Material Pre-test Post-test
XRD of Scale • Crystalline • Mixture • Main phase – Zn3(PO4)2●4H2O (Hopeite) • Trace phase – CaAl2Si7O18 ● 6H2O (Heulandite)
Scale on Submerged Al • Preliminary SEM results • Similar to constituents of MBLOCA scale • Aluminum and oxygen • Aluminum, phosphorous, and oxygen • Exception; trace amounts of zinc detected • Possibly more scale MBLOCA LBLOCA
Awaiting…. • Post-test analysis of bed • XPS Results • Another confirmation of scale constituents • Provides stoichiometric formula
SEM Captured Particle Scale
T2 Observations • Visible chemical product were detected • Measured aluminum concentrations are ~1/3 of that detected in T1 • The filtered concentrations of zinc, aluminum and calcium maybe lower than the total concentration • Membrane filters appears to capture more debris as compared to T1 • Turbidity has decreased to the lowest levels observed during the testing series • NEI beds in C2 and C3 measure head loss due to solution constituents • Chemical products may mainly be a zinc phosphate with trace amounts of aluminum and/or calcium products
Bench Top Experiments • Batch Corrosion test • Three temperatures (85, 60, 35 oC) • Three solution pH values (6.0, 7.2, 7.7) • Two time frames (24 hours and 30 days) • Aluminum only, aluminum and silicon, zinc only • Batch Dissolution/leaching test • Fiberglass dissolution in the presence of soluble aluminum • Three temperatures, pH values and two time frames • Concrete leaching test for UNM and Southern concrete samples • Path forward • Test plan will be re-visited after evaluation of current test result • More bench test for corrosion focused on zinc and aluminum materials • Another integrated tank test with blender bed
NRC Call • Kerry to discuss UNM position • UNM’s position is supported by four test • Basis for Conclusion • The release of corroded aluminum into solution is much less than predicted • Precipitation in the bulk solution is not likely to have occurred • If precipitates were to form, they would be unlikely to cause a significant increase in head loss • Conclusion • Chemical precipitates are expected to have no effect on the ECCS strainers at the STP plant for all LOCAs smaller than a 6-inch break • Likely valid for breaks up to 15 inches
Lab Tests Short Term Tank Test 30 Day Tank Tests Series 100: Leaching (concrete, debris) Series 200: Al corrosion T> 85 C Series 2000 -3000: Corrosion Test Max 30 day and initial release , variability Series 4000: Precipitation test Identification, characterization, variability Test 1 : Shake down Test 2: LBLOCA Test 1: Bed thickness to particulate Ratio 1 Test 2: Bed thickness to particulate Ratio 3 Test 2: Bed thickness to particulate Ratio 2 Test 4: MBLOCA Test 3: SBLOCA Thermodynamic Modeling Head Loss Calculator Precipitate calculator CASA