ML13319A725
| ML13319A725 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/04/2013 |
| From: | Cavallo J, Kinsey S, Zigler G Constellation Energy Nuclear Group |
| To: | Office of Nuclear Reactor Regulation |
| Morgan N | |
| Shared Package | |
| ML13319A601 | List: |
| References | |
| CCNPP-CHLE-009, Revision 2 | |
| Download: ML13319A725 (5) | |
Text
Considerations for using Marinite in Refined GSI-191 Chemical Effects Testing CCNPP-CHLE-009, Revision 2 November 4, 2013 Prepared by: Reviewed by: Approved by:
Gilbert Zigler, Craig Sellers, John Swailes, Jon Cavallo, Josh Wargo Tom Konerth Steve Kinsey
Jon Cavallo, Gilbert Zigler, and Stephen Kinsey Rev. 2, November 4, 2013 Considerations for using Marinite in Chemical Effects (CE) Testing
Background
Marinite is mostly used in NPP containment as a fire barrier on cable trays. Marinite is a generic term of a mixture of calcium silicate, calcium metasilicate (wollastonite), and re-enforcing fibers (fiberglass, organic fibers such as cotton). Johns Manville Marinite Board manufactured between 1906 and 1975 contained asbestos. Currently Marinite is made in the USA by BNZ Materials and comes in a variety of forms ranging from molded casts, boards, and flour. BNZ Materials Marinite I or M are the type of Marinite found in the CCNPP containment (Ref. 1, Attachment 13). BNZ Materials Marinite I or M boards have a nominal density of 46 lbs/cuft and are promoted as having high strength and damage resistance.
The following are the responses and recommended surrogate for chemical effects testing of Marinite following a hypothetical LOCA:
Outside a HELB ZOI:
Marinite outside a HELB ZOI will not be source of debris fines. Marinite outside a HELB ZOI would be either exposed to sprays or submerged. 1/2 thick pieces of BNZ Material Marinite I or M board are appropriate for CCNPP CE tests.
Inside a HELB ZOI:
Marinite debris from a HELB ZOI will be small pieces (0.5%), large pieces (2.7%) and 95.5% will remain intact on the cable tray as intact pieces (Ref 2, Table 3c1-2, Marinite Size Distribution, page 97). 1.3 %
of the Marinite inside a HELB ZOI is assumed to fail as fines (particulate) (Ref 2, Table 3c1-2, Marinite Size Distribution, page 97).
Marinite Small Pieces, Large Pieces, and Intact Pieces 1/2 thick pieces of Marinite I or M boards can be used as a surrogate for Marinite small pieces, large pieces, and intact pieces.
Marinite Fines:
Marinite fines can be used in CE testing where the transport of particulate is not an issue, e.g. beaker bench top tests. Marinite particulate can be purchased from BNZ Materials as Marinite Fines, a manufacturing byproduct from sanding and cutting of Marinite I and M boards. Marinite Fines is an appropriate surrogate for Marinite particulate from a HELB ZOI since the break-up by sanding and cutting would be analogous to the break-up of the Marinite board within the ZOI. Attached is the BNZ Materials analysis of Marinite Fines (Ref 3).
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Jon Cavallo, Gilbert Zigler, and Stephen Kinsey Rev. 2, November 4, 2013 1/2 thick pieces of Marinite I or M boards can be used as a surrogate for Marinite fines where the transport of particulate is problematic. Based on Ref 3, Figure 1 below shows that 99% of BNZ Marinite Fines have a size distribution between 44 and 150 microns (between Taylor mesh 325 and 100). For conservatism, the surface area of the equivalent Marinite board can be calculated assuming the Marinite particulate to be 44 microns in diameter 50%
45%
40%
35%
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25%
20%
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5%
0%
0 50 100 150 200 250 300 350 Particle SIze (Microns)
Figure 1: BNZ Material Marinite Fines Particle Size Distribution Surface Area of Marinite Board to Represent Fines in Chemical Effects Head Loss Testing Reference 1 determined that 0.104 cubic feet of Marinite board would become particulate debris in a design basis LOCA at CCNPP. Using the above evaluation of 44 micrometer diameter, this volume of Marinite particulate would produce an exposed surface area of 4,323 square feet. Such scaling ignores the surface contours and roughness of the Marinite board.
Recent evaluation of a sample of Marinite board from CCNPP determined the surface roughness to be Ra=6.3 micrometers. See Figure 2 for a photograph of a small piece of Marinite, approximately 1 inch long. Assuming each surface feature is a cone 6.3 micrometers tall with base of micrometers diameter and the surface is completely covered by such features would yield an exposed surface of 4.133 times the apparent board surface assuming a perfectly smooth surface. Therefore, scaling particulate to surface area without considering surface roughness results in greater than a 4 times over estimate of required surface area.
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Jon Cavallo, Gilbert Zigler, and Stephen Kinsey Rev. 2, November 4, 2013 Figure 2: Marinite Board, ~3 centimeters long, Surface Roughness Ra=6.3 micrometers Furthermore, use of a half inch thick board adds much more mass to the test, allowing any dissolution to proceed to far greater extent than could dissolution of 44 micrometer particles.
Marinite board used as a surrogate for Marinite particulate will have total surface area 25% of the total surface area of number of 44 micron spherical particles calculated to be produced for each break.
References
- 1) CCNPP Calculation CA06940 Rev. 0001, Computation of Aluminum and Marinite Board Debris Loads, March 23, 2009.
- 2) Attachment 3 to AEPNRC: 8054-02, NRC Ascension Number ML08770395
- 3) Fax from Norman R. Scheffer, Product Development, BNZ Materials, to Gilbert Zigler, ENERCON, dated 09/13/2013 (Attached)
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Attachment Fax from Norman R. Scheffer, Product Development, BNZ Materials, to Gilbert Zigler, ENERCON, dated 09/13/2013