ML053330025
| ML053330025 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 11/28/2005 |
| From: | Bauer J Exelon Generation Co, Exelon Nuclear |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2010-0209, RS-05-164 | |
| Download: ML053330025 (57) | |
Text
Exeb
- eneration www.exe]oT,.corp.com RS-05-164 November 28, 2005 U.S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, DC 20555-0001 Braidwood Station, Units 1 and 2 Facility Operating License Nos. NPF-72 and NPF-77 NRC Docket Nos. STN 50-456 and STN 50-457 Byron Station, Units 1 and 2 Facility Operating License Nos. NPF-37 and NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455 10 CFR 50.90 Subject :
Response to NRC Request for Additional Information With Respect to Request for License Amendment Related to Application of Alternative Radiological Source Term References :
(1)
Letter from K. R. Jury (Exelon Generation Company, LLC) to NRC, "Request for License Amendment Related to Application of Alternative Radiological Source Term," dated February 15, 2005 (2)
Letter from J. B. Hopkins (NRC) to C. M. Crane (Exelon Generation Company, LLC), "Braidwood Units 1 and 2, and Byron Units 1 and 2 -
Request for Additional Information," dated July 29, 2005 In Reference 1, Exelon Generation Company, LLC (EGC) requested an amendment to Appendix A Technical Specifications (TS), of Facility Operating License Nos. NPF-72, NPF-77, NPF-37, and NPF-66 for Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, respectively. The proposed amendment was requested to support application of an alternative source term methodology in accordance with 10 CFR 50.67, "Accident Source Term." In Reference 2, the NRC informed EGC that additional information was required to support the review of the amendment request. The NRC requested that the response be provided within 120 days from the date of Reference 2. Attachment 1 to this letter provides the EGC responses to the NRC request for information.
This proposed revision does not affect the supporting analysis for the original license amendment request as described in Reference 1. No other information submitted with Reference 1 is affected by this additional information. The No Significant Hazards Consideration and the Environmental Consideration provided in Attachment 1 of Reference 1 are not affected by this additional information.
November 28, 2005 U.S. Nuclear Regulatory Commission Page 2 EGC is providing the State of Illinois with a copy of this letter and its attachments to the designated State Official.
If you have any questions about this letter, please contact J. A. Bauer at (630) 657-2801.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 28'" day of November 2005.
Respectfully, Joseph A. Bauer Manager - Licensing Attachments: : Response to NRC Request for Additional Information : Calculation ATD&356, "Post LOCA Containment Sump pH," Revision 5 : Simplified Diagrams (For Information Only)
BRAIDWOOD STATION UNITS 1 AND 2 Docket Nos. STN 50-456 and STN 50-457 License Nos. NPF-72 and NPF-77 and BYRON STATION UNITS 1 AND 2 Docket Nos. STN 50-454 and STN 50-455 License Nos. NPF-37 and NPF-66 Response to NRC Request for Additional Information
A.
Iodine Leakage After a loss-of-coolant accident (LOCH), a significant portion of the inventory of core iodine is released to the containment and some of this iodine leaks to the outside. In the submittal, two release paths are identified : containment leakage and emergency core cooling systems (ECCS) leakage.
Containment Leakage Path The iodine from the damaged cue is released to the containment as 95% cesium iodide (CsI) and 5% as iodine (12) and hydriodic acid (HI). CsI and HI are soluble in sump water but 12 is scarcely soluble.
If the sump water is acidic some of the ionic iodine from CsI is converted to 1 2 and because of its low solubility it is released into containment atmosphere and some of A will leak to the outside. To prevent this from happening the pH of the sump water has to be maintained at the pH value of ~! 7.
Describe your program for controlling sump pH to maintain it basic. The description should include: (a) chemicals used for sump pH control; (b) the procedure and corresponding calculations for determining the amount of chemicals needed for neutralizing the effect of acidic chemicals in the containment such as boric, hydrochloric or nitric acids.
Response
Response to NRC Request for Additional Information The Byron/Braidwood Updated Final Safety Analysis Report (UFSAR),
Section 6.1.3.3, "Loss-of-Coolant Accident," describes the process for controlling sump pH. In the event of a large-break Loss-of-Coolant Accident (LOCA), both safety injection (SI) and containment spray JCS) will be initiated. The pH of the final sump solution is independent of the number of trains of ECCS and CS pumps in operation. The final sump pH is determined by the quantity of water and concentration of boron in the Refueling Water Storage Tank (RWST), the Reactor Coolant System (RCS), and the Sl accumulators and the quantity of water and concentration of sodium hydroxide (NaOH) educted from the containment spray additive tank (CSAT). The pH of the spray solution is determined by the CS pump suction source and the quantity of NaOH educted from the LSAT. The systems function in the same manner regardless of whether one or two ECCS/CS trains are Aeration. The residual heat removal (RHR) pumps will be transferred to the recirculation mode when the RWST reaches the Lo-2 level setpoint. The charging and SI pumps are then manually aligned for the recirculation mode. The CS pumps will continue to operate with suction from the RWST until the RWST reaches the Lo-3 level setpoint. The operator will then manually align the CS pump suction from the RWST to the recirculation sump. NaOH addition will continue until the CSAT reaches the Lo-2 level regardless of CS pump suction source (i.e., RWST or recirculation sump) and the NaOH addition has continued for a minimum of two hours.
The minimum final sump pH following a LOCA for Byron and Braidwood is established by Calculation ATD-0356, "Post LOCA Containment Sump pH,"
Revision 5, provided as Attachment 2 to this submittal. Calculation ATD-0356 determines the minimum post-LOCA sump pH based on the NaOH quantity, the borated water quantity, and boron concentration in the sump. The calculation differs Page 1 of 9 Response to NRC Request for Additional Information for Unit 1 and Unit 2 because Unit 1 is equipped with replacement steam generators and Unit 2 has its original steam generators.
The sump pH is calculated by determining the equilibrium quantities of the boron ionic species and sodium ionic species in the sump. These are calculated based on the amount of boric add and sodium hydroxide added to the sump, the sump pH, the total water volume in the sump, and the temperature of the sump. Also, the equilibrium quantities of hydronium ion (H30') and hydroxyl ion (OH-) are determined based on the temperature-dependent ionic activity product constant of water and the sump pH. The equilibrium pH is determined when the sum of ionic charges of all species pertinent to the boron and water in the solution and the ionic charge of sodium reduces to zero, defined as when the difference is <1 E-7.
Calculation ATD-0356 establishes three equations to describe the concentrations of all ionic species. The equilibrium pH is obtained analytically by solving the three equations simultaneously, using the Math Solver in MathCAD 5.0. The pH is verified if the sum of all ionic species reduces to zero (i.e., when the difference is <1 E-7).
Calculation ATD-0356 determined that a minimum pH of 8.0 would be established by the addition of a minimum of 2500 gallons of 30 wt% NaOH from the CSAT.
Following the initial chemical addition and stabilization of pH, the sump pH would only be impacted by the nitric acid (HN03) produced by irradiation of water and air and the hydrochloric acid (NCI) produced by irradiation of electrical cable insulation.
The plant-specific application of the guidelines for formation of HN03 and HCI provided in NUREG/CR-5950, "Iodine Evolution and pH Control," (Reference 1) is discussed as follows:
The Executive Summary provided in Reference 1 indicates that during a COCA, the most important acids in the containment will be HN03 produced by irradiation of water and air and HCI produced by irradiation or heating of electrical cable insulation.
The most important bases in the containment will be cesium hydroxide, cesium borate, and pH additives, such as NaOH. Some aspects of the timing of pH change during an accident can be obtained from the fission product release into containment. Initially, the sump water pH becomes basic because of cesium entering the sump water pool as hydroxide, borate, or carbonate. Once the fission products enter the sump water pool, the radiation dose rate is established, and HN03 begins to form and neutralize the basic solutes. A high concentration of fission products that contain basic solutes brings about a high initial pH but also a high radiation dose rate, which results in a relatively high production of HN03. For a typical pressurized water reactor (PWR) plant, the maximum duration that a basic pH may be maintained in the absence of pH control additives is approximately 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />. This time can be further reduced if boric acid or HCI becomes prominent he water pool.
Reference 1, Appendix B, provides the total HCI generation rate (g-mol/s) from gamma and beta radiolysis of Hypalon (i.e., electrical cable insulation) as follows :
R = RyH + RAH
Where:
and Where:
Response to NRC Request for Additional Information R,H = 1.32 x 10"15 x EY x N V
FVH = 8.70 X 10"6 X V
Attachment I Ey total gamma energy release rate (Mev/s)
EP total beta energy release rate (Mev/s)
N = total mass of Hypalon cable insulation (lbs)
V = containment free air volume (cc)
For the given mass of Hypalon and containment free air volume, the HCI generation rate is directly proportional to the post-COCA gamma and beta radiation in the containment.
A review of post-LOCA pH analyses prepared for previously approved alternative source term (AST) license amendments for comparable PWR Stations, including the Seabrook Station, indicates that the reduction in the initial pH of the sump water due to acidic sources such as HN03, HI, and HCI is considerably small because of pH control additives and the increased pH resulting from cesium entering the sump water providing a stronger base to neutralize the effect on the acidic sources produced during a LOCA. The Seabrook Station is comparable to the Braidwood and Byron Stations with respect to key parameters that directly impact the sump pH such as :
" thermal power level (i.e., core activity, the primary source of radiation) ;
containment size (i.e., gamma air borne dose causing radiolysis of air for HN03 and cable insulation (HCI)) ; and containment sump (i.e., gamma sump water dose causing radiolysis of water (HN03))-
Seabrook performed the 30-day containment sump water pH analysis with and without acids produced from irradiation of water, air, and electric cable insulation.
The analysis concluded that the additional acids formed during a LOCA would reduce the initial pH by less than 0.1 pH units (i.e., Reference 2). The NRC staff ependently determined that the production of HCI and HN03 resulted in a change pH of less than 0.1 after 30-days (i.e., Reference 3).
Because a sump water pH analysis has not been performed to establish the effect of the post-LOCA acidic sources on the initial sump pH of 8 at the Braidwood and Byron Stations, the following assessment is provided to establish the potential reduction of the sump water pH due to the effect of post-LOCH acids.
A comparison of the critical parameters used in determining the initial sump pH is provided in Table 1, "Comparison of Critical Parameters Determining Initial Sump Response to NRC Request for Additional Information Water pH," for Byron, Braidwood and Seabrook. Note that the initial Braidwood and Byron sump water pH is 8, which is less than the Seabrook pH value of 8.6.
Table I Comparison of Critical Parameters Determining Initial Sump Water pH
- Values taken from Reference 2 Since the post-LOCH gamma and beta radiations are very important for the irradiation of the sump water, containment air, and cable insulation that cause the acidic source, the parameters that determine the post-LOCA radiation are investigated and compared in Table 2, "Comparison of Design Parameters Determining Post-LOCA Radiation." The core thermal power levels of Seabrook, Braidwood and Byron are the same (i.e., 3,659 MWt). Therefore, the post-LOCA isotopic core inventories in Curie/MWt for these stations will be similar. The post-LOCA core activity release fractions are provided in the Regulatory Guide (RG) 1.183 (i.e., Reference 51 Table 2, "PWR Core Inventory Fraction Released Into Containment," which should be the same for these stations. The parameters that determine the post-LOCA gamma and beta doses that irradiate the containment air, sump water, and cable insulation, include:
0 the size of the containment and sump ;
Page 4 of 9 Description of Braidwood Braidwood Parameter Determining Seabrook Byron Byron Initial Sump Water pH Unit 1 Unit I Unit 2 Refueling Water Storage Tank Volume Released (Maximum 428,000 457,904 457,904 Value) (gal)
Refueling Water Storage Tank Boron Concentration (Maximum 2900 2500 2500 Value) (Kom)
Spray Additive Tank Volume 8520 2500 2500 Release (Minimum Value) (gal)
Spray Additive Tank Sodium Hydroxide Concentration 19 30 30 (Minimum Value) (wt%)
Reactor Coolant System Mass 492,200 620,800 562,457 (Ibm)
Reactor Coolant System Boron Concentration (Maximum value) 4000 2300 2300 (ppm)
Accumulator Volume (Maximum Vslue) (gal in each of four 6596 7217 7217 accumulators)
Accumulator Boron Concentration (Maximum Value) 2900 2400 2400 (ppm)
Calculated Sump Water Initial 81
&0 8.0 pH I
I I
I
Attachment I Response to NRC Request for Additional Information
" the activity removal mechanisms (mainly of the containment spray and containment/ECCS leakage) ;
" the spray removal coefficients for elemental iodine and particulates ; and
" containment and ECCS leak rates.
The similarity in the major key parameters for these stations, for which small variations are considered insignificant, will produce approximately the same post-LOCA gamma and beta integrated dose in the containment air and sump water. This produces similar quantities of acidic sources, which tend to neutralize the initial sump water pH in the same manner as analyzed for the Seabrook Station. The relatively larger containment dilutes the source and the higher containment leakage rate removes the airborne activity faster at the Braidwood and Byron Stations. This results in a slight reduction in the gamma and beta irradiation of the containment air and cable insulation, and thereby produces a correspondingly slightly smaller amount of nitrogen ions and HCL The smaller sump volume concentrates the source at the Braidwood and Byron Stations slightly increasing the gamma and beta irradiation of the sump water and thereby produces a correspondingly slightly larger amount of hydrogen ions which combines with the nitrogen ions generated by irradiation of the containment air to produce the HN03.
Table 2 Comparison of Design Parameters Determining Post-LOCA Radiation
- Values taken from Reference 3 Using the similarity of the parameters contributing to the post-LOCA gamma and beta doses, the parameters for the acidic sources (including the quantity of Page 5 of 9 Description of Braidwood Braidwood Parameters Determining Seabrook Byron Byron Post-LOCA Radiation Unit 1 Unit I Unit 2 Core Thermal Power Level (MWt) 3659 3658 3658 Total Containment Volume (ft) 2.704E+06 2.850E+06 2,850E+06 Sprayed Containment Volume (ft) 2.309E+06 2.350E+06 2.350E+06 Uwspmyed Containment Volume 1950E+05 5100005 TOOOE+05 Air Transfer Rate Between 26,000 130,000 130,000 Containment Regions (cfm)
Containment Spray Removal Rates Before DF is Reached (1/hr)
Elemental Iodine 20 20 20 Particulate 575 6.0 so Containment Leak Raw (%/day}
0-24 hrs 0.15 0.2 0.2
>24 hrs 0.075 0.1 0.1 Containment Sump Volume (m) 69,159 58,506 58,506 ECCS Leak rate (gpm) 1033
Attachment I Response to NRC Request for Additional Information uncovered cable insulation outside of conduit) are compared in Table 3, "Comparison of Critical Parameters for Post-LOCA Acidic Sources." The radiation exposure to covered cable insulation is reduced due to the shielding associated with the steel conduit. The resulting NCI will be confined inside the conduit thereby preventing its intrusion to the sump water due to the sealed conduit, conduit trays, and multi-layer arrangement.
Table 3 Comparison of Critical Parameters for Post-LOCA Acidic Sources
- Values taken from Reference 2 Based on the similarity of the key parameters in Tables 1, 2, and 3 that control the sump pH, the conclusions of the Seabrook Station pH analysis and the NRC staff determination of sump pH, it is concluded that the 30-day post-LOCA containment sump water pH change due to the acidic source at the Braidwood and Byron Stations would be less than 0.1 pH units and that the final sump water pH would be approximately 7.9, which is considerably higher than the pH of 7 required by the RG 1.183 to eliminate any ionic 12 conversion of CsI.
ECCS Recirculation Leakage Path :
(2)
Provide the basis for assuming the value of 276,000 cc/hr for the ECCS recirculation leakage rate used in the AST LOCA analysis. (NO ANSWER REQUIRED)
The NRC determined that question A.2 does not need to be answered because sufficient detail was provided in Reference 4.
In the ECCS leakage path leading to the Borated Water Storage Tank (BWST), the sump water will mix with the remaining borated water in the tank. Since the BWST water contains between 2300 and 2500 ppm of boron in the form of boric acid, the pH of the mixture of sump and BWST water will have lower pH (most probably well below 7). Lowering the pH of the sump water will cause the conversion of ionic iodine into the elemental form and its corresponding release to the reactor water storage tank (RWST) air space. This effect will increase the total release of radioactive iodine from engineering safety features and cause correspondingly higher radiation doses.
Page 6 of 9 Description of Braidwood Braidwood Parameters for Post-LOCH Seabrook Byron Byron Acidic Sources Unit 1 Unit I Unit 2 Mass of Uncovered Electrical Cable 50,000 11,359 11,359 Insulation (Ibm)
Post-LOCA 30-Day Gamma and Beta Integrated Dose in Containment Sump 13E+07 3.3E+07 3.3E+07 Water (rads)
Post-LOCA 30-Day Gamma and Beta 7.1E+07 I
7.1 E+07 I
7.1 E+07 Integrated Dose in Containment Air (rads)
Response
Response to NRC Request for Additional Information Was this effect included in the licensee's analysis? If it was included, provide its description and the analyses for determining its significance to the overall release of radioactivity in the ECCS recirculation leakage path.
For the purposes of this response, the BWST is referred to as the RWST at Byron and Braidwood Stations. Sump leakage back to the RWST was not considered based on the design and operation of the ECCS. The ECCS is depicted in simplified diagrams ECCS-1, "ECCS System," and ECCS-2, "ECCS Ring," provided as to this submittal. During the injection phase of the LOCA, water is injected from the RWST into the RCS cold legs. When the RWST Lo-2 level is reached, Emergency Operating Procedure 1/2B(w)EP ES-1.3 is entered to align the ECCS for the recirculation mode of operation, i.e., suction is switched to the containment sump. The steps for aligning the ECCS for the recirculation mode are summarized below (refer to simplified Diagram ECCS-1):
1. The containment sump isolation valves, 1/2SI881 1A/B, automatically open on the RWST Lo-2 level signal.
3. The containment sump isolation valves, 1/2SI881 1A/B, are verified open.
4. The residual heat removal (RHR) pump suction isolation valves from the RWST (1/2SI8812A/B) are manually closed.
5. The centrifugal charging (CV) pump recirculation valves, 1/2CV8111/8114 and V2CV81 1 W8116, are isolated.
It should be noted that the CV pump recirculation valves return to the pump suction and not the RWST.
6. The recirculation low path to the RWST for the safety injection (SI) pumps is then isolated by closing 1/2SI8814, 1/2SI8920, and 1/2S18813. At this time, the Sl pumps suction is still aligned to the RWST.
If RCS pressure is above the shutoff head of the Sl pumps, the Sl pumps will be shut down.
- 7. The discharge of the RHR trains is then split by closing 1/2RH8716A/B
- 8. The suction header for the CV and Sl pumps is then cross-tied by opening 1/2SI8807A/B, and 1/2SI8924. The RWST is still the suction source to the CV and Sl pumps.
- 9. The CV and Sl pump suction is then aligned to the discharge of the RHR pumps by opening 1/2CV8804A and 1/2SI8804B. At this time, back flow into the RWST is prevented by check valve 1/2SI8926 (on SI pump suction side of 1/2SI8806) and check valve 1/2CV8546 (on CV pump suction side of MY 12D and V2CV1 12E). The check valves are held closed by RHR pump discharge pressure.
10. The RWST is then isolated from the CV and Sl pump suctions by closing 1/2CV1 12D, 1/2CV1 12E, and 1/2SI8806.
When the above steps are completed, the ECCS system is isolated from the RWST on both the suction side and the Sl pump recirculation. The CS pumps are still running with suction aligned to the RWST. The realignment of the CS pumps to the containment sump is performed when the RWST reaches the Lo-3 level setpoint by performing the following steps (refer to simplified Diagram ECCS-2):
B.
Iodine Removal
Response
Response to NRC Request for Additional Information 1. The CS pump suction from the containment sump isolation valves, 1/2CS009A/B are opened.
Note that in this lineup the CS pumps do not have a recirculation flow path back to the RWST. A portion of the CS pump discharge flow is directed through the CS pump eductor back to the pump suction in order to inject NaOH.
As described above, once the ECCS has been realigned for the recirculation mode of operation, potential leakage paths back to the RWST are isolated utilizing at least two valves in series, typically a check valve in combination with a motor operated valve (MOV). For a short period of time during realignment of the RHR pump suctions from the RWST to the containment sump, leakage back to the RWST is prevented by a single check valve (i.e., 1/2SI8958A/B) until the RHR pump suction isolation valves from the RWST (i.e., 1/2S18812A/B) are closed. The ECCS valves are tested in accordance with the Inservice Testing (IST) Program required by Technical Specification 5.5.8, "Inservice Testing Program," to ensure meeting their specified engineered safety position. During testing, check valves 1/2S18926 and 1/2CV8546, preventing back flow to the FWVST, are verified closed utilizing one of the following methods : 1) ultrasonic testing, 2) acoustic testing, or 3) pressure testing. The IST of check valve 1/2Sl8958A/B requires a pressure test be performed. The MOVs used to isolate flow paths back to the RWST are also stroke tested to the closed position in accordance with the IST Program. Additionally, MOVs are tested in accordance with the MOV Program used to satisfy the recommendations in Generic Letter (GL) 89-10, "Safety-Related Motor-Operated Valve Testing and Surveillance," dated June 28, 1989, and GL 96-05, "Periodic Verification of Design Basis Capability of Safety-Related Power-Operated Valves,"
dated September 18, 1996.
Based on the discussion above, back leakage to the RWST is not considered in the analysis, consistent with the current analysis of record.
(4)
Provide the reason why natural deposition of elemental iodine was not considered in your analysis.
RG 1.183, Appendix A, "Assumptions for Evaluating the Radiological Consequences of a LWR Loss-of-Coolant Accident," assumption 3.2 states : "Reduction in airborne radioactivity in the containment by natural deposition within the containment may be credited. Acceptable models for removal of iodine and aerosols are described in Chapter 6.5.2, 'Containment Spray as a Fission Product Cleanup System, ` of the Standard Review Plan (SRP), NUREG-0800 (Ref, A-1) and in NUREGICR-6189, 'A Simplified Model of Aerosol Removal byNatural Containment' (Ref A.2). The latter model is incorporated into the analysis code RADTRAD (Ref. A-3). The prior practice of deterministically assuming that a 50% plateout of iodine is released from the fuel is no longer acceptable to the NRC staff as it is inconsistent with the characteristics of the revised source term."
Page 8 of 9
References Response to NRC Request for Additional Information Table B, "Conformance with Regulatory Guide 1.183 Appendix A (Loss-of-Coolant Accident)," of Attachment 7, "Regulatory Guide Conformance Tables," included in Reference 4 provided the following comment: "For BIB, the RADTRAD computer program, including the Powers Natural Deposition algorithm based on NUREGICR-6189, is used for modeling aerosol deposition in Containment. No natural deposition is assumed for elemental or organic iodine. The lower bound (10%) level of deposition credit is used."
RG 1.183, Appendix A, assumption 3.2 does not require crediting natural deposition for elemental iodine. RG 1.183 states that natural deposition of airborne radioactivity may be credited. EGC did not choose to credit natural deposition of elemental iodine because elemental iodine only makes up approximately 4.85% of the total iodine released. Neglecting credit for deposition of elemental iodine results in a more conservative estimate of onsite and offsite dose consequences because more iodine is available to be released.
NUREG/CR-5950, Iodine Evolution and pH Control," December 1992 Letter from M. E. Warner (FPL Energy Seabrook, LLC) to NRC, "Seabrook Station Response to Request for Additional Information Regarding License Amendment Request 03-02," dated May 24, 2004 Letter from V. Verses (NRC) to M. E. Warner (FPL Energy Seabrook, LLC),
"Seabrook Station, Unit No. 1 - Issuance of Amendment Re : Alternative Source Term," dated February 24, 2005 (4)
Letter from K. R. Jury (Exelon Generation Company, LLC), to NRC, "Request for License Amendment Related to Application of alternative Source Term," dated February 15, 2005, (5)
Regulatory Guide (RG) 1.183, "Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Plants," dated July 2000 Page 9 of 9 Response to NRC Request for Additional Information BRAIDWOOD STATION UNITS 1 AND 2 Docket Nos. STN 50-456 and STN 50-457 License Nos. NPF-72 and NPF-77 and BYRON STATION UNITS 1 AND 2 Docket Nos. STN 50-454 and STN 50-455 License Nos. NPF-37 and NPF-66 Calculation ATD-0356, "Post LOCH Containment Sump pH," Revision 5
COMMONWEALTH EDISON COMPANY CALCULATION TABLE OF CONTENTS Exhibit D NEP-12-02 Revision 5 PROJECT NO.
9135-198 CALCULATION NO. ATD-0356 REV. NO. 5 PAGE NO. 5 DESCRIPTION PAGE NO.
SUB-PAGE NO.
T1, 1 TITLE PAGE 2-4 REVISION
SUMMARY
5 TABLE OF CONTENTS 1.0 PURPOSE/OBJECTIVE 6
2.0 METHODOLOGY AND ACCEPTANCE CRITERIA 6
3.0 ASSUMPTIONS 6-7 4.0 DESIGN INPUT 7-9
5.0 REFERENCES
10-11 6.0 CALCULATIONS 11,13-40 7.0
SUMMARY
AND CONCLUSIONS 12 ATTACHMENTS rVa APPENDIX A1-A5
CALCULATION NO. : ATD-0356 PROJECT NO.
PAGE NO. 6 9135-198 1.0 PURPOSE/OBJECTIVE COMMONWEALTH EDISON COMPANY The purpose of this calculation is to determine the minimum final containment recirculation sump pH following a LOCK The result of the calculation will be used to update the design basis for the Byron/Braidwood post LOCA containment sump pH for Units 1 and 2. The Unit I results address the impact of the replacement steam generator (RSG) project.
2.0 METHODOLOGY and ACCEPTANCE CRITERIA Exhibit E PIEP-12-02 Revision5 The minimum post LOCA containment recirculation sump pH is determined based on the sodium hydroxide (NaOH) quantity, the borated water quantity, and boron concentration in the sump for both Units I and 2. The calculation differs for each unit because Unit 1 is equipped with a new steam generator and Unit 2 has its original steam generator.
The sump pH will be calculated by determining the equilibrium quantities of the boron ionic species and sodium ionic species in the sump. These can be calculated based on the amount of boric acid and sodium hydroxide added to the sump, the sump pH, the total water volume in the sump, and the temperature of the sump. Also, the equilibrium quantities of hydronium ion (H30"') and hydroxyl ion (OH-) can be determined based on the temperature-dependent ionic activity product constant of water and the sump pH. The equilibrium pH is determined when the sum of ionic charges of all species pertinent to the boron and water in the solution and the ionic charge of sodium reduces to zero (defined when the difference is < 1 E-7).
This calculation will establish three equations to describe the concentrations of all the ionic species. The equilibrium pH will be obtained analytically by solving the three equations simultaneously, using the Math Solver in MathCAD 5.0. The pH is verified if the sum of all ionic species reduces to zero (defined when the difference is < 1 E-7).
The purpose of this calculation is to determine the minimum containment recirculation sump pH. Technical Specification 3/4.6.2.2 Bases states that the post LOCA sump pH shall be 8.0 to 11.0. This will be used as the acceptance criteria for this calculation, 3.0 ASSUMPTIONS
- 1) The safety injection accumulator water temperature is assumed to be at 900F. This is a conservative estimate of the minimum temperature of this water and will result in a higher density of water (thus the mass of boron).
- 2) All RCS, RWST, CSAT, and Sl accumulator volumes are conservatively assumed to reach the containment recirculation sump.
REVISION NO. : 5
COMMONWEALTH EDISON COMPANY Exhibit E NEP4202 Revision 5 CALCULATION NO. : ATD-0356 PROJECT NO.
PAGE NO.
9135198 3.0 ASSUMPTIONS, contd
- 3) The extended form of the Debye-Huckel equation is applicable to the range of ionic strength considered in this calculation.
- 4) The equation for the molal equilibrium quotient, Q11, is based on ionic strength derived from molality. The ionic strength determined in this calculation is based on molarity. In dilute solutions, molality and molarity are approximately equal. Because this calculation deals with dilute solutions, molality and molarity are assumed to be equal.
- 5) The approximate ionic radii used in this calculation are those at 250C. The effect of temperature on the approximate ionic radii is assumed to be negligible.
- 6) All species and ions in solution are assumed to be in equilibrium; therefore, the results are based on steady state analysis.
- 7) Not used.
- 8) Not used.
- 9) The density of the solution in the containment recirculation sump (containing both borated water and NaOH) is assumed to be the density of pure water at the applicable sump temperature stated in Design Input 15. Increasing the solution from a specific gravity of 1.00 to 1.01 (conservative maximum based on level of boron and caustic in the sump) yielded a negligible difference in the sump pH.
4.0 DESIGN INPUTS
- 1) The density of water at atmospheric pressure and various temperatures used in the calculation for the areas noted is as follows (interpolated as necessary from Ref. 1, page 4-4) :
Use Temperature, OF p,_Ib/ft3 Units1,2 containment recirculation sump 185 (Design Input 15) 60.45 SI accumulator 90 (Assumption 1) 6112 RWST 35 (Design Input 5) 62.42
[REVISION NO. : 5
CALCULATION NO.
- ATD-0356 PROJECT NO.
PAGE NO. 8 1
911354198 1
4.0 DESIGN INPUTS conVd COMMONWEALTH EDISON COMPANY Exhibit E NEP4202 Revision 5
- 2) The pressure, temperature, and density of water used in the-RCS mass determination are shown below. The RCS nominal pressure and temperature conditions are used and the density is interpolated from Ref. 2, based on these conditions.
Pressure, psiq Temperature, 'F 12, lb/ft3 Unit 1 2,235 (Ref. 3) 569.1 (Ref. 25) 4518 Wit 2 2,235 (Ref. 3) 569.1 (Ref. 25) 4&58
- 3) The maximum boron concentration in the RWST is 2,500 ppm (Ref. 6 with clarification on fuel cycle being at or greater than 6 for both units at each station from Ref. 7).
- 4) The maximum RWST volume is 457,904 gal (Ref. 8). This is the full capacity of the RWST defined as 100% top of overflow pipe.
- 5) The RWST water temperature is at its Technical Specification minimum of 35,OF (Ref. 6).
This is conservative because the density of water (thus the mass of boron) is higher at lower temperatures.
- 6) The maximum boron concentration in the SI accumulators is 2,400 ppm (Ref. 9 with clarification on fuel cycle being at or greater than 6 for both units at each station from Ref. 7).
- 7) The maximum S1 accumulator volume is T%217 gal per each of the four Sl accumulators (Ref. 10).
- 8) Per Ref. 11, a 30-36 wt% NaOH solution can be used in the CSAT. A 30 wt% NaOH solution is used in this calculation because it is conservative ; resulting in a smaller mass of NaOH addition to the sump, and therefore, a lower sump pH.
- 9) The minimum NaOH solution addition from the CSAT is 2,500 gallons per Appendix A.
Appendix A calculates where the LSAT LO-2 level alarm must actuate to assure a minimum of 2500 gallons of NaOH is delivered to the containment spray system. Reference A.5.14 determines the CSAT LO-2 level setpoint necessary for alarm actuation at the level calculated in Appendix A.
- 11) The maximum RCS volume of Unit 2 is 12,340 ft3 (Ref. 26). The maximum volume is defined as hot, 0% tubes plugging and includes the steam generator pressurizer steam volume.
PREVISION NO. : 5
4.0 DESIGN INPUTS contd COMMONWEALTH EDISON COMPANY Exhibit E NE1012-02 Revision 5
- 12) The maximum RCS volume of Unit 1 is 13,620 ft3 (Ref. 26). The maximum volume is defined as hot, 0% tubes plugging and includes the steam generator pressurizes steam volume.
- 13) The steam generator pressurizes volume for Units 1 and 2 is 1,800 fe (Ref. 15). The steam generator pressurizes volume increases 1.6% from cold to hot conditions (Ref. 27). This yields a hat beam generator pressurizes volume of 1,828.8 W (1.016 x 1,800 ft).
- 14) The maximum steam generator pressurizes water volume for Units 1 and 2 is 1,656 fe (Ref. 16). The steam generator pressurizes water volume increases 1.6% from cold to hot conditions (Ref. 27). This yields a hot steam generator pressurizes water volume of 1,682.5 ft3 (1.016 x 1,656 ft3).
- 15) A range of containment recirculation sump temperatures from the data and curves in Ref.
27 was examined. The sump temperatures in Ref. 27 are maximum values, and lower temperatures are also possible post-LOCA. The total temperature range for the three scenarios in Ref. 27 over the time period required to drain the minimum CSAT volume were reviewed (approximately 165 - 260'F), down to a temperature of 150OF (to account for lower temperatures). (Note that the time period to drain the minimum CSAT tank volume ranges from : a) 2,500 gal, or the minimum CSAT volume + 120 gpm, or 2 eductors at maximum flow, 21 min to b) 2,500 gal + 55 gpm, or 1 eductor at minimum flow, = 45 min.) Through sample runs, it was determined that a temperature of approximately 1850F minimizes the sump pH.
Also, the sump pH throughout the temperature range of 150 - 260OF did not differ from the pH results at 185OF by more than +0.04. A sump temperature of 185OF was, therefore, selected.
- 16) The approximate effective ionic radii of H+ and 01 in aqueous solutions at 250C are 9.0 and 3.5 respectively (Ref. 18, p. 8A).
- 17) The Debye-Huckel constants for Units I and 2 at the containment recirculation sump temperature of 1850F (see Design input 15) are A = 0.5842 and B = 0.3440 (Ref. 18).
- 18) The molecular weight of boron is 10.81 lb/Ibmol (Ref. 19). The molecular weight of NaOH is 39.997 lb/lbmoI (Ref. 19). The molecular weight of boric acid is 61.84 lb/IbmoI (Ref. 19).
- 19) The temperature of the NaOH solution in the CSAT is 1300F. This is the maximum temperature for the area that the LSAT is located in per the EQ design basis document (Ref.
20). This is conservative because the density of NaOH solution (thus the mass of NaOH) is lower at higher temperatures.
- 20) The density of the 30% NaOH solution at 130OF is 10.898 lb/gal (calculated / interpolated from Ref. 19 using 8.345 lb/gal per 1 gM/CM3 conversion factor).
I REVISION NO.: 5
CALCULATION NO. : ATD-0356 PROJECT NO.
PAGE NO.
9135198 10
&0 REFERENCES
- 1) "Cameron Hydraulic Data", C. C. Heald, hgersoll Rand, Seventeenth Edition, 1988.
- 2) "Steam Tables", American Society of Mechanical Engineers, Sixth Edition, 1993.
- 3) Calculation 222-7720-A19, Revision 3.
- 4) Deleted.
- 5) Deleted.
COMMONWEALTH EDISON COMPANY Exhibit E NEP42A2 Revision 5
- 6) Braidwood Technical Specification 3/4.5.5, Amendment No. 55 - Unit 2, 56 - Unit 1 ; Byron Technical Specification 3/4.5.5, Amendment No. 65.
- 7) "5 Year Nuclear Division Planned Outage Schedule", Revision 34, 9/26/96.
- 8) NDIT 960009, Revision 0, verified 10/23/96 in "Status Change for NDIT 960009" letter from H. Kim to R. Peterson (N DIT references calculation ATD-0 111 Revision 2).
- 9) Braidwood Technical Specification 3/4.5.1, Amendment No. 55 - Unit 2, 56 - Unit 1 ; Byron Technical Specification 3/4.5.1, Amendment No. 65.
- 10) Braidwood Technical Specification Bases 3/4.5.1, Amendment No. 25 ; Byron Technical Specification Bases 3/4.5.1, Amendment No. 38.
- 11) Braidwood Technical Specification 3/4.6.2.2, Amendment No. 4 ; Byron Technical Specification 3/4.6.2.2, Amendment No. 14.
- 12) NDIT 960181, Revision 0 (NDIT references "Safety Parameter Interaction fist for ComEd Braidwood Cycle 7" dated 10/96).
- 13) Deleted.
- 14) Deleted.
- 15) NDIT 950028, Revision 1 (NDIT references USFAR Table 5.4-9 and Westinghouse calc note CN-TA-93-182 Rev. 0, p. 12).
- 16) Braidwood Technical Specification Bases 3/4.4.3, Amendment No. 33 ; Byron Technical Specification Bases 3/4.4.3, Amendment No. 44.
- 17) Deleted.
[REVISION NO.: 5
5.0 REFERENCES
cont'd COMMONWEALTH EDISON COMPANY CALCULATION NO. : ATD-0356 PROJECT NO.
PAGE NO.
9135-198 11
- 18) "Lange's Handbook of Chemistry", J. A. Dean, McGraw-Hill Company, Fourteenth Edition, 1992.
- 19) "Perry's Chemical Engineering Handbook", Sixth Edition, McGraw-Hill Company.
- 20) EQ Design Basis Document PMED-P-BB-EQ-DBD-00.
- 21) "Basic for Instrument Scaling Methodology", TID-EII&C-21, Rev. 0, 1115/93.
- 22) "Acidity Measurements in Elevated Temperatures. VI. Boric Acid Equilibria", R. E. Mesmer, C. F. Baes, Jr. and F. H. Sweeton, Inorganic Chemistry, Vol. 11, No. 3, 1972.
- 23) "Chemistry of Natural Waters", S. D. Faust and 0. M. Aly, Ann Arbor Science Publishers, Inc., 1981.
- 24) "Aquatic Chemistry", W. Stumm and J. J. Morgan, John Wiley & Sons, 1970.
Exhibit E NEP-12-02 Revision 5
- 25) NDIT 960119, Revision 3 (NDIT References NFS NDIT 960206, Revision 2 "Revised Braidwood Unit 1 Cycle 7 Reload Design Key Parameter Checklist").
- 27) NDIT 960159, Revision 5 (NDIT references WCAP-10326-A and Framatome calculation "Containment LBLOCA Analysis-Long Term Cooling" document number 32-1266155-02 dated 11119197).
6.0 CALCULATIONS The detailed calculations for the minimum post-LOCA containment recirculation sump pH for Unit 2 (with its original steam generator) are shown first (pages 13-26). The detailed calculations for the minimum post-LOCA containment recirculation sump pH for Unit 1 (with its replacement steam generator) are shown second (pages 27-40).
The rest of this page is intentionally left blank.
I REVISION NO. : 5
Exhibit E NEP-12,02 Envision 5 CALCULATION NO.
- ATD-0356 PROJECT NO.
PAGE NO.
91=98 12 7.0
SUMMARY
AND CONCLUSIONS COMMONWEALTH EDISON COMPANY
- 1) Based on the minimum NaOH quantity and the maximum borated water quantity and boron concentration in the recirculation sump, the post LOCA minimum containment recirculation sump equilibrium pH for Unit 2 (with original steam generator) is 8.0.
- 2) Based on the minimum NaOH quantity and the maximum borated water quantity and boron concentration in the recirculation sump, the post LOCA minimum containment recirculation sump equilibrium pH for Unit I (with replacement steam generator) is 8.0.
The rest of this page is intentionally left blank.
REVISION NO. : 5
CALCULATION NO. ATD-0356 6.0 CALCULATIONS -UNIT 2 V RCStot := 12340-8, V PREs : = 1828.8-ft3 V 1103SMst
- = 1682
.5"83 T RCSag : = 569.1 PpRES :=2235 11 PluEssan != Nr PRES - l' PRESUrat V pRES st1n = 146.3 -ft RCSwat - - I RCStot - ' PRESstrn V RCSwat = 1.21937-104 ft3 Ma PRCSwaP=4T5&
lb ft, a14
- =9
.0 a OH
- = 3.5 1481 hl" 13 We 39 Mwt NaOH 1,997 We 11 nest ' 0 457904. gal V accu
- = 28868-gal P NaOH = 10.898-lb gal VNaOH :=2500-gal REVISION NO. 5 COMMONWEALTH EDISON COMPANY PROJECT NO. 9135-198 PAGE NO.
13 Maximum Total RCS volume (Design Input 11)
Steam generator pressurizer volume (Designinput 13)
Maximum steam generator pressurizes water volume (Design Input 14)
Average RCS temperature, F (Design Input 2)
Steam generator pressurizes pressure, psig (Design Input 2)
Minimum pressurizes steam volume um RCS borated water volume EXH03rr E NEP-12-02 Revision 5 RCS water density at nominal pressure and temperature shown above {Destpn input a}
Ionic radius of H* (Design input 16)
Ionic radius of OH- (Design Input '16)
Molecular weight of boron, B (Design input 18)
Molecular weight of sodium hydroxide, NaOH (Design Input 18)
Maximum RWST borated water volume (Design input 4)
Max. borated water quantity in accumulators, 4 x 7,217 gal each (Designinput7)
NaOH solution density at 130E and 30 wt °lo NaOH {Design input 20}
Minimum NaOH solution volume in spray additive tank (Design input 9)
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
14 6.0 CALCULATIONS - UNIT 2 cont'd 2300 B MS 1106 P w185 =60.45 lb Density of water @ 185 *F (Design Input 1) fte I JH r OH ionic activity product of water T :=358.15 K Sump temperature in Kelvin (or 1850F) (Design input 15)
A :=x.5842 B :=x.3440 Debye-Huckel Constants (Design input 17)
CBEB borated water charge balance error CBEN sodium charge balance error Ionic charge of species I
Molecular weight of boric acid (assign inputle) 2500 Pic 6 2400
)1a s Calculate Sl Accumulator borated water density at 90OF and a boron conc. of 2400 porn From Eq. D-10 of Reference 21, calculate the mass fraction of the boric acid solution (expressed as ppm w/o the 106 factor) :
M"03BO3 PPm H3BO3accu ' '- B aocu 1%
rB PPM H3EI03accu -_.01372951 REIFIS101'sl NO. 5 61.84 B0.3 mole COMMONWEALTH EDISON COMPANY RWST boron concentration (Design input 3)
RCS boron concentration (Design Input 10)
Accumulator boron concentration (Design Input 6)
Ionic strength in sump solution activity coefficient of HI ion activity coefficient of OH-ion EXIMBU E NEP-12-02 Whim 5
CALCULATION NO. ATD-0356 PROJECT N. 9135-198 PAGE NO.
15 6.0 CALCULATIONS - UNIT 2 cont'd From Eq. D-11 of Reference 21, calculate the weight % of boric acid within the solution basm
- 0 Wn H3BOMW 100 95C bmxu _-1.37295097 From Eq. D-12 of Reference 21, calculate the weight density of the solution, p BAaccu P w9o : = 62.12-lb Density of water @ 90 *F (Design Input 1) fi3 P BAaccu : " P w9O'[ I + (0.0035. %C baccu) I BAaccu = 62.418507 - lb ft, Calculate borated water quantity in Accumulators, M accu, based on accumulator volume of 28,868 gallons M =11 " V aah P BAaacacu
.40878657-10 5 lb (Based on the conversion I - gal =0.13368056 -ft, )
Calculate RCS borated water density at 569.1 *F and 2235 psia and a boron conc. of 2300 ppm
""' FBB03 PPm H3B03rcs i -, : B rcs
- PMMB03rcs =0,01315745 Mwt B O"C brcs 1'1'm H3B03rcs' 100
%C bres 1.31574468 P BAres
- :-" P RCSwat* I I + (0.0035-%C bres)]
P BA=s = 45,78990075. lb ft, REVISION NO. 5 COMMONWEALTH EDISON COMPANY EXHIBIT E NEP-1202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
16 6.0 CALCULATIONS - UNIT 2 cont'd Calculate borated water Quantity in RCS.
M rcs M rcs :=V RCSwat*P BArcs Mws"15"=13-105.1 (Based on the conversion I
- gal = 0.13368056 -ft3 Calculate RWSTbomted water density at 35*17 and a boron conc. of 2500 ppm Fpm H3B03rwst :
PPM H3B03rwst = 0.0 1430157 0 '
"OC brwst
- -:7 Mtn H3B03rwsf 100
%C brwst =1.43015726 P w35 :=62.42-lb Density of water @ 35 *F (Design Input 1)
W BArwst w35* I I + (0.0035-%C b BArwst = 62.73 244646 - lb fl:3 Calculate boraNd water Quantity in RVIST, 14 rWst ms
, based on RWST volume of 457,904 gallons V P BArwst M
Twst = 3.84003259-106
Ib (Based on the conversion I -gal = 0.13368056 -ft3 Calculate Boron mass, M., in RWST, Accumulators, RCS :
M rwst'B rwst - I-M accu, B accu + B rcs'M rcs MB=1.14623914-0 -lb REVISION NO. 5 COMMONWEALTH EDISON COMPANY MWt H3B03 st Mwt B EXHMrr E NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO. 17 6.0 CALCULATIONS - UNIT 2 cont'd Calculate NaOH mass, MN,OH, in 30% solution (Design Input 8)
M NaOl-IsIn : 7 V NaOH P NaOH M NaOH :7M NaOHsln*0.3 MNaOH =8.1735-103 -lb Calculate net water mass inside containment, MHO 14 1120 4hof rwt + m accu +m res +m NaOHsln) - M B - M NaOH 064686867-10 6 lb Calculate water Volume, V, inside containment (at 185*F per Design Input 15) :
P ms VV "11767521S-l06 d -liter Calculate Molar concentration of boron Mol andNaOH, MolNa0H M B 14 NaOH VAM V V Mwt NaOH 10113 =(122095625-gm-mole Mol NaOH = 0.04258311 -gnmole
~
liter liter REVISION NO. 5 COMMONWEALTH EDISON COMPANY Based on the conversion( I -e =28
.31684659-liter)
EXHIBIT E NEP-1102 Revision 5
6.0 CALCULATIONS - UNIT 2 cont'd
[1-13BOg = H3BO3
[B(OH)4-1 = BOH4 IB2(OH)i] = 13201-17
[B3(01-1) 1a
]
B30HIO
[B4(OH)14-1 B401-114
[H-] = H
[OH-] = OH
[Na"] = Na REVISION NO. 5 COMMONWEALTH EDISON COMPANY CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
18 Setup three equations to solve for equilibrium sump pH :
NOTE : For MathCAD purposes, the concentrations of various species are denoted as follows in all of the following equations:
Condition 1 :
The sum of the molar concentration for all the boron ionic species should be equal to the molar concentration of boron, M01B, in the sump. This yields Equation I below.
Mola = H3803+BU44+2220'7+3-830H,0+4-B40H14 Eq. 1 Condition 2 :
The borated water charge balance error, CEEB, represents the sum of the ionic charges of all species pertinent to boron and water in solution. The ionic charge of H+ is 1. The is charge of OH -, B(OH)4-, B2(OH)f, and 83(OH)10- is -1. The ionic charge of B4(OH)j is -2. Ionic charge values are from Ref. 22. CEEB is then defined as follows:
CEEB =
H - OH - BOH 4 - B20H 7 - B30H 10 B40H 1 4 EMMU E NEP-1202 Revision 5 The sodium charge balance error, CBEN, represents the ionic charge of sodium (defined as +1 per Ref. 18) and is defined as follows:
CBEN = Na Electroneutrality requires that the sum of ciz i (c is molarfty and z is ionic charge) of all species and ions in solution equals 0, thus the sum of CEEB and CBEN equals 0. This yields Equation 2 below.
-Na = 14 - OH-BOH 4 - B201 B30H 10- 2-B40H 14 Eq. 2
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
19 6.0 CALCULATIONS - UNIT 2 cont'd Condition j :
The ionic strength, 1, of solution is calculated as follows :
I = 0.5(c,Z,2 + c2z22............ + cZ,2)
(Ref. 18) where c is molarity and z is ionic charge. Utilizing the ionic charges defined in the Condition 2 section with the above equation yields Equation 3 below.
2-1 = Na+H+0H+B0H44B2UU7+B30H1 All the variables in Eqs. 1, 2 and 3 will be defined in terms of pH, H3BO3, and 1.
Per Ref. 22, the boron ionic species can be defined from equilibrium quotients as follows:
BOH4 =
Q 1I-H3B03-OH B201-1, = Q21-H3B03 2_ OH B30H IO =
Q31-H3B033.014 13401-114 = Q42-H3BO3 4.OH2 Per Ref. 22, the molal equilibrium quotients, Q,,, Q21, Q31 and Q42 are defined as follows and can be reduced, given : T=358.15 K Q11 = 10 Q11 =
=+28.6059+0.01207&T-13.2258-log(T) +(0.3250- 0.00033-T).I- 0.0912.
T
/2756.1 _ 18.966+ 5.8354*LK T)
Q 21 :--10 ~ T REVISION NO. 5 Q 21 = 4.288921-103 COMMONWEALTH EDISON COMPANY 3.544684 + (0.206811).l - 0
.0912
.I1'5
+ (B4014 14).4 Eq. 3 EXH[Brr E NEP4202 RKhm 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
20 6.0 CALCULATIONS - UNIT 2 cont'd 3339.5 8'084+1.497. 1og(T)
Q31 :=10( T Q42 :=10
-log q yielding :
Per Ref. 23, the equilibrium quantifies of the H and OH ions are defined as follows :
THIWI10401-11 = k,,,
and YH1H+1 = I O-PH yielding :
H =
I JH Per Ref. 18, individual a of the Debye-Huckel theory :
41 =
10 l0",
.10
.511 YOH =
10 [ (I +B.. 0H.1 0.5)]
Per Ref. 24, the ionic activity product constant of water, k,, is calculated as follows :
pk, = -log k,,,,
4470.99 _ &OV5+031700T T
REVISION NO. 5 Q 31 = 1.15808569° 1 Os 820.0 134.50+42.105,108( 1)
Q 42 = 5.94241376-10g Acz J1 Is I +Baf 1.5 VA' COMMONWEALTH EDISON COMPANY OH kw try OH coefficient, 1,, may be estimated using the following equation kG1 "P.5 EXIMIT E NFP4202 Revision 5
CALCULATION NO, ATD-0356 PROJECT NO. 9135-198 PAGE NO.
21 OH =
6.0 CALCULATIONS - UNIT 2 cont'd yielding :
Given : T =35&15 YH =
10
=3.11811884" 10 -"
Substitute Na : -- Mol NaOH REVISION 1410. 5 "70.99 b.0875 +4.0120&T1 T
(0.5842)-10-5 11 +(0.3440).9.0-10.51 COMMONWEALTH EDISON COMPANY H=9 a OH =31 YOH =
10 and 3, and given the following, all unknowns can be determined.
=(122095625 _ g nrw mole Mol NaOH =0.0425831 1 - gnvnuAe liter liter Na = (104258311 - gnmWe liter A=0.5842 B =0.344 (0.5842)-1D.5 (0.3440-3.5-10.5L T OH and k w into the expressions for H and OH to obtain :
Using the expressions and values developed for Q1 0203040 IFI and OH with Equations 1, 2 E&MU E NEP4212 R=Wm 5 Also far simplicity, define a variable V for 1-131303, Equations 1, 2, and 3 can be rewritten in terms of three variables (namely pH, l and V).
With three equations and three variables, the variables can be solved simultaneously.
The forms of the equations to be solved are shown on the net page. The Math Solver in MathCAD 5.0
', used to solve the equations.
¢.Il CALCULATIONS UNIT-2 rQnt'd Guess values:
Given Equation 1 0.22095625=V + 10 Equation 2 0.04258311=,
10P" A,103 Equation 3 10 2 1=0.04258311 +
REVISION NO
. 5 10 107 PH A.10.5 11 + (8-9.0-103)1 0104307249 i Find(I, V,pH) = 0.14340439
~ 8.05381635 ;
COMMONWEALTH EDISON COMPANY CALCULATION NO. ATD-0356 PROJECT NO
. 9135-198 PAGE NO.
22 I =0.045200 V =0.1426000 p14 =8.05 3.5"684+ (0.206811)-1-0,09121 1 '
lo-p" to lo-pH. 10 w
A
, 10'5
[,+ cB.3.5.10.5)l J
k w
(
A _P
/
l0'PH.10 [1+(a1
[ 1 +
(B~3.Sd0.5) l
+
(2.Q 21) 5"6843-(0.206811)1 _
0.091211' MEBr[ E NEP-12-02 R-6im 5 IO PH, 10 3.344614+(0106810 0.09121"' ]
[ +183.3.10.3}l1 10 -PH_10 A10 5 0'
5
[1+(B-15.10.3)]
I
+ (3.Q 31)
_V3.
w Q21 0"
IO-PH-10 (Q21)'V 2
A d0
. 5 0 [1 + (0,3.3.10.5) rA10" lI 1+1B
, 3.5?.5311
+ (4.Q42)
. V4.
A10.5 10' PH.10 Q 31' lo-,H, 10 (Q 31)' V3 A-10'5
[i+(8.3.3.10.5)1 10-P11
. 10 [1+(8-3.5.10.
(2-Q 42). V4 k w, 0.5 IO pH, 10 [t+ 1e~3.s (4-Q 42). VA 10 Pt
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
23 6.0 CALCULATIONS - UNIT 2 cont'd To verify the equilibrium sump pH ; the pH, H,B03, and the ionic strength (l) that were calculated on the previous page are put into the following calculations. The pH is verified when three conditions are met :
- 1) the absolute difference between the concentration of boron used to develop the equations on the previous page and the concentration of boron resulting from the following calculations is < 1 E-7.
- 2) the sum of ionic charges of all species pertinent to boron and water in solution and the ionic charge of sodium reduces to zero (defined when the absolute difference is < 1 E-7).
- 3) the absolute difference between the ionic strength calculated on the previous page and the the ionic strength resulting from the following calculations is < 1 E-7.
(a) Assume the solution ionic strength, 1 : :::0,04307249 The a y H =0.84369386 The activity coefficient of OH -,
y 0H Js :
A,12.10.5 70H := 10 1 `1+B-'01F10
.5
)J 7 OH = 0.799825 (b) Assume an equilibrium sump pH :
PH := 8.05381635 product constant of water, kw, at 185 °F (358.15 Kelvin) is:
The ionic a T =358.15 The equilbrium quantity of Ht is 1
p 4470.99 _ 6,0875 +0.01706-T)
T 811884 " 10 13 H = 1.04712556" 10-8 REVISION NO. 5 COMMONWEALTH EDISON COMPANY 2 05 coefficient of H, y H, is :
A.1 a
\\1+B
.3 H10.S1 0
EXHIBrr E NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
24 6.0 CALCULATIONS - UNIT 2 cont'd The equilbrium quantity of OH-is OH : = ---
w 1400H 0141 = 141279789-10-5 (c) Assume H31303 Molal'ty of 0.14340439 :
H3B03 =0.14340439 The Molal equilibrium quotients of boric acid are :
T
}28.6059-0.012078.T-13.2258-log(T)+(0.3250-0.00033-T).1-0.0912.1 1.5 Q11 :=10 1 Q 1I = 3.57089321 -1 Q 31 = 1, 15808569-10 Q 42 = 5.94241376-10 8 REVISION NO. 5 Q 21 = 4.288921 -10 12756.1 _ 18.966 + 5.835-IoLX T)
Q21 := 10 ~-T
~3339.5 _ 8.084+1.497-1og(T)
Q 31 := 10
~
T 112920.0 _ 134
.36+a2
.105 log(T)
Q42 :--10 k T
COMMONWEALTH EDISON COMPANY EMMBU E NEPAM Revision 5
CALCULATION NO. ATO-0356 PROJECT NO. 9135-198 PAGE NO.
25 6.0 CALCULATIONS - UNIT 2 cont'd The equilibrium quantities of boric acid species are :
BOH4 :=Q 11 -MB010H BOH 4 = 0.02259713 B20H 7
- =Q 21-H3BO3
- 2. OH B20H 7 =0.00389213 B30H I 0 := Q 3 1 -H3B033. OH B40H 14 := Q 42-F1313034 OH2
B40H 14 =4.89373837 " 1 Concentration of boron, based on the above equilibrium quantities, is :
Cone B := 1-131303 + BOH 4 + 2-13201-17 + 3-1330H 10 + 4-1340H 14 Cone B = 0,22095627 Cone B -.22095625 = 2-10-8 (Condition 1 is met) which is the same as Check Borated water charge balance error, CEEB, is CBEB := H - OH - BOH 4 - B20H 7 - B30H CBEB =-0.04258313 Sodium charge balance error, CBEN, is COMMONWEALTH EDISON COMPANY 8301-10 = 0.0 15071
- 2. B40H 14 MEN
- z Mol NaOH (divide by unit to eliminate dimensions) mole gn ---
liter CBEN = 0.04258311 CBEB + CBEN = 10-S (Condition 2 is met)
REVISION NO. 5 0.22095625 - gmmole liter EMIEBU E NEP-1202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
26 6.0 CALCULATIONS - UNIT 2 cont'd Verify ionic strength of the solution :
I so Na := CBEN Na + H + OH + BOH 4 + B20H 7 + B30H 10+ (1340H 14).2
=aOWOW COMMONWEALTH EDISON COMPANY 2
which is the same as assumption (a) 1 =0.04307249
- I = 1. 10-8
(Condition 3 is met)
Since conditions 1, 2 and 3 are met, the equilibrium sump pH=8.05381635 The rest of this page is intentionally left blank.
REVISION NO. 5 EXHMrr E NER1202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
27 6.0 CALCULATIONS -UNIT 1 V RCStot = 13620-ft, Maximum Total RCS volume (Design input 12)
V pRES :
1828.8-ft3 Steam generator pressurizer volume (Design Input 13)
V PRESwat = 1682.5-ft' Maximum steam generator pressurizer water volume {Design Input 14}
T RCSavg : = 569.1 Average RCS temperature, F (Design Input 2)
P pRES
- = 2235 Steam generator pressurizer pressure, prig (Design input 2)
V PRESstrn ] = V PRES -
Sstm ' 1463 -ft3 Minimum pressurizer steam volume P
V RCSwat V RCStot - V PRESstrn V RCSwat 1,34737-104 ft3 Maximum RCS borated water volume PRCSwaf=4508
. lb RCS water density at nominal pressure and temperature shown above (Design Input 2)
= 9.0 a OH
- = 3.5 MwtB :=
10.81 ode 39 Mwt NaOH -
.997 mole rwst
~ = 457904. gal Maximum RWST borated water volume (Design input 4)
V accu
- = 28868-gal PNaOH [=I0T9& lb gal
- = 2500- gal REVISION NO. 5 fe COMMONWEALTH EDISON COMPANY Ionic radius of H" (Design Input 16)
Ionic radius of OH- (Design Input 16)
Molecular weight of boron, B (Design Input 18)
Molecular weight of sodium hydroxide, NaOH (Design Input 18)
Max. borated water quart EMMU E NEP4202 Whim 5 in accumulators, 4 x 7,217 gal each
{Design input7)
NaOH solution density at 130E and 30 wt % NaOH (Desi put 20)
Minimum NaOH solution volume in spray additive tank (Design input 9)
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
28 6.0 CALCULATIONS -UNIT 1 cont'd B
I FH PPM F131303accu REVISION NO. 5 accu MwtB PP'H3B03accu ".01372951 COMMONWEALTH EDISON COMPANY RCS boron concentration (Design Input 10)
Accumulator boron concentration (oesign Input s)
PwI85 :=60A5-lb Density of water @ 185 *F (Design Input l) ft3 f
ionic strength in sump solution activity coefficient of H+ ion activity coefficient of 01 ion 70H k w ionic activity product of water T :=358.15 K Sump temperature in Kelvin (or 185°F) (Design Input 15)
A :=0.5842 B =03440 Debye-Huckel Constants (Design Input 17)
CBEB borated water charge balance error CBEIN sodium charge balance error Ionic charge of species i MW'H3Btjj'-
61.84 Molecular weight of boric acid (Design input 18)
We Calculate Sl Accumulator borated water density at 90OF and a boron conc. of 2400 ppM From Eq. D-10 of Reference 21, calculate the mass frac the 106 factor) :
Mwt H3BO3 EXIMBU E NEP4202 Revision 5 n of the boric acid solution {expressed as ppm w/o
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
29 6.0 CALCULATIONS - UNIT I cont'd From Eq. D-11 of Reference 21, calculate the weight % of boric acid within the solution
%C baccu.
PPm MB03accu' 100
%C baccu 1.37295097 From Eq. D-12 of Reference 21, calculate the weight density of the solution, P BAaccu P w9o 62.12 - lb Density of water @ 90 *F (Design Input 1) ft P BAaccu, P w90' I I + ( 0.0035-%C baccu)
P BAaccu = 62.418507 - lb ft, Calculate borated water quantity in Accumulators, M accu, based on accumulator volume of 28,868 gallons M accu :=v accu*P BAaccu M accu =2.40878657-105 Ib (Based on the conversion I -gal =0.13368056 -fta Calculate RCS borated water density at 569.1 *F and 2235 n0a and
-a boron conc. of 2300 prom PPM H3BO3rcs
REVISION NO. 5 PPM MB03rcs = 0.0 1315745
%C brcs PPm MB03rcs'] 00
%C brcs 1.31574468 P BArcs P RCSwat'l I +
(0.0035-%C brcs)
P BArcs 45.78990075. lb ft, COMMONWEALTH EDISON COMPANY EMMU E NEP4202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
30 6.0 CALCULATIONS - UNIT I cont'd Calculate borated water auantitv in RCS.
rcs : = V RCSwat'P BAms rcs "k 16959386-105.1b (Based on the conversion 1, gal = 0.13368056 -ft3 Calculate-RWST borated water density at 35'F and a boron conc. of 2500 ppm AMM"t PPM H3 1303s"t i o B rwSt H31303 Mwt B PPM 1-131303rwst = 0.0 1430157
%C brwst
. = PPm H3BO3rwst' 100
%C brwst =1.43015726 P w35 62.42-lb Density of water @ 35 *F (Design input 1) fl~
P BArwst ~ = P w35* I I + (0.0035.%C brW5 01 P BArwst = 62.73 244646 -
lb ft3 Calculate borated water quantity in RWST, M rwst, based on RWST volume of 457,904 gallons rust V rwst'P Bhmst rwst 3.84003259-106 -lb
{Based on the conversion I - gal =0.13368056 -ft' Calculate Boron mass, M., in RWST, Accumulators, RCS 14 B : = 14 nxt 1B rwst REVISION NO. 5 MB=1.15971968-104 -lb COMMONWEALTH EDISON COMPANY accu + B res, M ITS rcs EXINBU E NEP4202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO. 31 6.0 CALCULATIONS - UNIT I cont'd Calculate NaOH mass WaOH, in 30% solution (Design Input 8)
M NaOHsin ~' V NaOH' P NaOH Hsln' 0.3 MNaOH =&I735-I0' -lb Calculate net water mass inside containment, MH20 st + M accu + M rcs + M NaoHsln) - M B - M NaOH
=4.70534493 " 10 6 -lb Calculate water Volume. V.. inside containment (at 185*17 per Design Input 15) :
P Q85 W =120414443-10' -liter Calculate Molar concentration of boron Mole, and NaOH, Mo l NaOH
=(122077659 ymm-mole REVISION NO. 5 COMMONWEALTH EDISON COMPANY Based on the conversion( 1
, 3 = 28.31684659 -liter)
M NaOH NaOH V W' Mwt NaOH M01 NaOH = 0.04205391 - gnmole liter EXMrr E NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO. 32 6.0 CALCULATIONS - UNIT I cont'd E04 up three __eqWaj equations to solve for equilibrium sump-DH-;
NOTE : For MathCAID purposes, the concentrations of various species are denoted as follows in all of the following equations :
[1-13BO~J = 1-131303
[B(OH)4] = BOH4
[B2(OH)7-1 = B201-17
[B3(OH)10-]
B30HIO
[B4(OH)14-1 13401-114
[H-) = H
[01-11 = OR Nal = Na Condition 1 :
The sum of the molar concentration for all the boron ionic species should be equal to the molar concentration of boron, MoI B, in the sump. This yields Equation 1 below.
REVISION NO. 5 CBEN = Na COMMONWEALTH EDISON COMPANY IBB03 + BOH 4 + 2,B20H B30H io + 4-B40H 14 Eq. 1 EMBNE NEP-1202 Revision 5 Condition 2 :
The borated water charge balance error, CEEB, represents the sum of the ionic charges of all species pertinent to boron and water in solution. The ionic charge of H+ is 1. The ionic charge of OH -, B(OH)4-, B2(OH)f, and B3(OH)10- is -1. The ionic charge of B4(OH)14 is -2. Ionic charge values are from Ref. 22. CEEB is then defined as follows:
CBEB =
H - OH-BOH 4 - B20H 7 - B30H 10 - 1B40H 14 The sodium charge balance error, CBEN, represents the ionic charge of sodium (defined as +1 per Ref. 18) and is defined as follows :
Electroneutrality requires that the sum of c,z, (c is molarity and z is ionic charge) of all species and ions in solution equals 0, thus the sum of CEEB and CBEN equals 0. This yields Equation 2 below.
-Na =
14 - OH - BOH 4 - B20H 7 - B30H 10 B40H 14 Eq. 2
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
33 6.0 CALCULATIONS - UNIT I cont'd Condition 3 :
The ionic strength, 1, of solution is calculated as follows :
All the variables in Eqs. 1, 2 and 3 will be defined in terms of pH, H31303, and 1.
Per Ref. 22, the boron ionic species can be defined from equilibrium quotients as follows :
BOH4 =
Q II-H3B03-OH B20H7 = Q2j-H3BO32OH B30H10 = Q31'H3BO33.014 B40H14 = Q42-H3BO34OH2 Per Ref. 22, the molal equilibrium quotients, Q1 1 1 Q211 Q31 and Q42 are defined as follows and can be reduced, given : T =358.15 K 1573.21 +28.6059+0.01207&T-13.2258-log(T) +(0.3250- 0.00033-T)-l- 0.0912-1 1.5 Q11 = 101 T
Q11 =
I = 0.5(c,z,2 + c2z22.
........... + CnZn2)
(Ref. 18) where c is molarity and z is ionic charge. Utilizing the ionic charges defined in the Condition 2 section with the above equation yields Equation 3 below.
2.1 = Na+H+OH+BOH4+B2OH7 +B30H,o+(B40HI4)-4 Eq. 3 12756.1 _ 18.966+ 5.$35. log( T)
Q21 :=10 ~ -T REVISION NO. 5 Q 21 = 4.288921 - 103 COMMONWEALTH EDISON COMPANY 3.544684+ (0,206811).l - 0.0912-11'S1 EXMrr E NEP-1202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO, 34 6.0 CALCULATIONS - UNIT I cont'd 3339.5 8.84+
01.497. JoE(T)
Q31~10( T
-109 1';
yielding :
REVISION NO. 5 Q 31 =1. 15808569-105 82o Q42~10
(
12 T
.0 134 56+4ZI05-log(T)
Q 42 = 5.94241376-10, Per Ref. 23, the equilibrium quantities of the H and OH ions are defined as follows :
and IH[H+l = 1 O-PH THIH%H[OH1 = k.
yielding :
H =
I JH Per Ref. 18, individual activity coefficient, ji, may be estimated using the following equation of the Debye-Huckel theory :
Ac z 12.10.5 I + B-a i. P.5 VA, M
W&')
COMMONWEALTH EDISON COMPANY OH = H,y Fry OH Per Ref. 24, the ionic activity product constant of water, kw, is calculated as follows:
pk, = -log kw 44M99 _ 6.0875 + 0.01706-T T
Y OH =
10
&01 "15 (I +B'$ 00'5 )
ENMIT E NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
35 6.0 CALCULATIONS - UNIT I cont'd yielding :
Given
- r=35&15 Substitute
- 14470.99-6.0873--0+
.01706.
10 ~- -
T T)
=3.11811884 " 10 1'
7 JH OH kw 11111101H Na : = Mol NaOH solved simultaneously.
REVISION NO. 5 (0.5842)-l0' 5 11 +- (0.3440).9.0.1 0.51 0.22077659
-pi-mole liter
]I = 9 a OH = 30 A = 0.5842 B =0.344 T OH and k w into the expressions for H and OH to obtain 10" pH 11PH 7 JH COMMONWEALTH EDISON COMPANY "I IT I OH Na =0.04205391 - grmmole liter 1
(0.5942).Io" 10H= 10 [5 +(0.3440 ).3.5,10-111 ImPTIm and 3, and given the following, all unknowns can be determined.
M01 NaOH = 0.042053 91 - gin-mole liter 3.11811884 13 10
( 0.5842)l O 'S 1+(0.3440).3.5.1 0.5h Using the expressions and values developed for Q1 I IQ21,Q31 IQ42, H and OH with Equations 1, 2 Also for simplicity, define a variable V for H3BO3, Equations 1, 2, and 3 can be rewritten in terms EAMU E NEP-1202 Revision 5 of three variables (namely pH, 1 and V}. VVith three equations and three variables, the variables can be The forms of the equations to be solved are shown on the next page. The Math Solver in MathCAD 5.0 3 used to solve the equations.
CALCULATION NO. ATO-0356 PROJECT NO. 9135-196 PAGE NO 36 6.0 CALCULATIONS -UNT1c_onfdd Guess values:
I =0.045200 V =0.1426000 pH =8.05 Given EquationI 0.22077659--Vi
- 1013 544684+ (0.206811)1 _ 0.0912.11'54 Equation 2 0.04205391=
Equation 3 10 2.1=0.04205391 +
10- P11
-. /A 10
' 5 (8-9.0.1ti.5\\
REVISION NO. 5 0.0425323 1
Find(I,V,pH)= 0.14402951 8.0455942 COMMONWEALTH EDISON COMPANY
. w A,10.5~
IOP" 10~(1+(Ba.1.10")
10"p" 10 L w
+(2'Q21).V2.
A.10.5
,1+
EmmI7 E NEP-12-02 Revision 5 3.544684+( 0206811 )J -0.0912 41 )
1 C~
3.544684+(0.206811) 4 _ 0091211' 5). V.
+ (3.Q 31 ;
10-01 10 A,10.5
[t + 1Ba.sP )J
~~
/11,10.3 5
10" Px -10 1+
3.510 Q 21' (Qzl) V 2
I f A. P'S 19 01-1 0 tl+(B-3.s.30.s ~
J
+ (4"Q 42), V4.
A40.5 10"rx.10 IOPH 10 10-PH.10 A.10'5 11+ 1H~3.S~I 'S~)
A10.5
,2 (1+(83.3.10- })1 V3
.. W (Q 31)
A105 lo-Px, 10 ()+(e-3.5-10"
( 2 Q 42)
(4-Q 42) V4+
IO Px 10 A10
.5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
37 6.0 CALCULATIONS - UNIT 1 cont°d To verify the equilibrium sump pH ; the pH, H3BO3, and the ionic strength (I) that were calculated on the previous page are put into the following calculations. The pH is verified when three conditions are met:
- 1) the absolute difference between the concentration of boron used to develop the equations on the previous page and the concentration of boron resulting from the following calculations is < 1 E-7.
- 2) the sum of ionic charges of all species pertinent to boron and water in solution and the ionic charge of sodium reduces to zero (defined when the absolute difference is < 1 E-7).
- 3) the absolute difference between the ionic strength calculated on the previous page and the the ionic strength resulting from the following calculations is < 1 E-7.
(a) Assume the solution ionic strength, 1 : ::0.0425323 The activity coefficient of H*, Y H, is Y H = 0.84424457 The activity coefficient of OH-, Y OH Js Y OH =0.80072577 (b) Assume an equilibrium sump pH :
pH :=8.0455942 roduct constant of water, k.,,, at 185 °F (358.15 Kelvin) is :
The ionic ac T =358.15
=3.11811884-10 13 The equilbrium quantity of H* is 10-pH YH H = 1.06644269" 10 REVISION NO. 5 COMMONWEALTH EDISON COMPANY
_ 6.0875 i-0.01206-T1 YOH.-_
Err E
NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
3 8 6.0 CALCULATIONS - UNIT I cont'd The equilbrium quantity of OH-is OH :=
k w 11, fly OH OH = 4.32516875-10-s (c) Assume H,BO3 morality of 0.14402951 :
1 143B03 :=0.14402951 The Moral equilibrium quotients of boric acid are :
!=+28,6059+0.012078-T-13.2258-IoL( T)+(0.3250-0.00033-T).1-0.0912-I 1.51 101 T rN,VISION NO. 5 Q11=31015401 03 r2756.1 - 18
.9b6+5
.$35-14T})
Q) 21 - 10
` -T Q 21 = 4.288921 - 103
/3339.5 _ 8.084+ 1.497-1ojKT)
Q1 31 -10 ~-T Q 31 = 1.15808569 " 10' 12820.0 _ 134.56 + 42.105-log( T)
T Q42 :--10 Q 42 = 5.94241376-101 COMMONWEALTH EDISON COMPANY EXHIBIT E NEP-1202 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
39 6.0 CALCULATIONS - UNIT 1 cont'd The equilibrium quantities of boric acid species are :
BOH B20H 7 := Q 21-H313032
. OH B20H 7 = 0.00384817 B30H 10 :_
134011 14,=
12 Q A,).H3BO3 4. OH Z B40H 14 = 4.78382113 -107' Concentration of boron, based on the above equilibrium quantities, is :
Comnc C"" B = 0.22077661 022077659 z= 2-1 Check Borated water charge balance error, CEEB, is CEEB :=H-OH-BOH 4 - B20H 7 - B30H CBEB =-0.04205392 Sodium charge balance error, CBEN, is CBEN Mod NaOH (divide by unit to eliminate dimensions)
We CBEN =0.04205391 ASION NO. 5 B03-OH H31303 3 OH COMMONWEALTH EDISON COMPANY BOH 4 = 0.02224001 830H 10 = 0.0 1496574 2-B20H7 + 3-830H 10 + 4-1340111 which is the same as (Condition I is met) 2-B40H I CBEB + CBEN =-2 " 10 *
(Condition 2 is met)
=(122077659-g nmr-nmuoAl e liter EXHI]Brr E NEP-12-02 Revision 5
CALCULATION NO. ATD-0356 PROJECT NO. 9135-198 PAGE NO.
40 (Final) 6.0 CALCULATIONS - UNIT I cont'd Verify ionic strength of the solution :
Na +H+ OH +BOH4+B2OH7+B30HIO+ (1340H 14)'
sol 2
so, = 0.04253231 which is the same as assumption (a)
I =0.0425323 Na :=CBEN The rest of this page is intentionally left blank.
IISION NO. 5 COMMONWEALTH EDISON COMPANY (Condition 3 is met)
Since conditions 1, 2 and 3 are met, the equilibrium sump pH = 8.0455942 MMMU E NEP4202 Revision 5
FROM :
SGRP REVISICN-NO. : 04 5 nx r6 II52Z43114 COMMONWEALTH EDISON COMPANY I CALCULATION NO.
- ATD-0356 PROJECT NO. 9135-196 PAGE N{). A1 Byron/Braidwood Unit 1 and Unit 2 Determination of Minimum Delivered Volume of NaOH Prepared By/Date :
Reviewea By/Date App; ovea BylOa:e :
Appendix A
-!6-9'7 1 :*16 P.02 Essh E NEP-1202 NO%
5
FROM SGRP
^Mi'. t+6 iE-13-97 A.1 PurposelObjective A.2 Moth odologytAcceptance Criteria tr = 1r A.3 Assumptions A.3.1 Deleted.
2 Deleted.
REVISION NO. :-1)4-15 COMMONWEALTH EDISON COMPANY 1 CALCULATION NO.
- ATO-0356 PROJECT NO. 9135-196 PAGE NO. A2 The purpose of this appendix is to determine the highest final Containment Spray Additive Tank (CSAT) level, cased on the lowest initial CSAT level, required to deliver a minimum of 2500 gallons of NaOH to the Containment Spray System. Past revisions of this calculation have demonstrated that delivering a minimum of 2500 gallons of NaOH (30 wt/0 at 130°F) will satisfy recimulation sump minimum pH -equiremenis
. The highest final CSAT level required to supply 2500 gallons is used as the System Safety Limit for calculating the CSAT 1-4-2 level alattn setpoint per Reference A.5.14. Therefore, minimum recirculation sump pH will be calculated Dried on a minimum volume of 2500 gallons NaOH delivered to the Containment Spray System.
The tank is a right circular cylinder with flanged and dished heaos (Reference A.5.3 and A.5.4).
This calculation is only concerned with the cylindrical portion of the tanK since the hearts are outside the scan of the level measuring instruments. The volume of a right circular cylinder is :
The highest final CSAT level is based upon the lowest initial CSAT level mina: the change m level corresponding to 2500 gallons.
Initial CSAT level is based on the lowest permissible fill level of ;he tanK minus (2)1Ll-CS021 instrument uncertainty Minimum sump pH is calculated assuming 30% NaOH concentration at 130°F ;design inputs 8 and 20). These assumptions result in the lowest allowable Na0H specific gravity and the lowest NaOH mass avsfable to the Contairment Spray System. which i5 Conservative Level transmitter (2)1LT-CS021 scaling is based cn higher NaOH specific gravity (per Byront6raidwood EWCS Equipment/Corn ponert Engineering Oata), therefore, actual CSAT lever would be higher than indicated level used on these specific gravity conditions. 9y assuming the lowest specific gravity NaOH solution
. the total mass of NaOH delivered to the Cc-ntwnment Spray System is conservative (lowest) regardless of level measurement unce,i'tainty assoc.ateci with variation in NsOH specific gravity
. Therefore. allowances for vanation in NaOH concentration or temperature are not necessary in determining (2)11-1-03021 level indicator uncena:nty Funhermore. the CSAT LO-2 level alarm setpoint calculated in Reference A.5.14 accounts for the maximum potential change in NaCH specific gravity from calibrated conditions. Therefore. level measurement uncertainty associateo with changes in NaOl-1 specific gravity is bounded for determination of rec,rcuiation sump minimum pH.
The results of this calculation a e used as input for other calculations. There are no direct acceptance criteria foi the results of this calculation Erhibit E N EP-12-02 Revision 5 A.3.3
.1 'IS essurned that the operator c ores the CS eduztor additive valves (2)1C5019AIB ediately after ?ne Spray Additive TanK LO-2 level alarm is received. and that spray tt " I.
P.33
FROM SGRP I CALCULATION NO. - ATO-056 PROJECT NO. 9135-196 PAGE NO. A3 A.3.4 The volume displaced by the pipe wall of the fill line is assumed to be pegligible. (Per Reference A.5.12, the area of metal ir. 4" Schedule 40 pipe is 3.174 in', which equals approximately 0.16 gal/ft of pipe.)
A.4 Design input AAA Tank Dimensions per Reference A 5.3 ono A,5,4:
A*2 The minimum fill level for the CSAT is 78.8% per References A.5.13, A.5.9 and A.5.10.
A.4.3 Deleted.
AAA Deleted.
A.4.5 The maximum uncertainty (excluding changes in NaOH concentration) of (2)lLI-CS021 is
+/- 5.0% per Reference A.5.11.
AX References A. 5.1 Calculation SM-C$046A, Revision A. "Containment Spray Additive Tank Level Switch 01 LS-CS046A." (Byron & Braidwooa)
A.5.2 Calculation 5M-C$0468. Revision A. 'Containment Spray AaCitive Tank Level Switch (2)ILS-CS0468.' (Byron & Braidwood)
A.5.3 Vendor Orawing NL-10753. Revision 15. "8'-0" O.D. x 13*-4" High (Tan. To Tan.)
Additive Tank." (Byron)
A.5.4 Vendor )Drawing NL- 0758, Revision 15. "8'-8" O.D. x 13'-4" High {Tar?. To Tan.} Spray Additive Tank.' (Braiawooci)
A5.5 1 HwEP-1. Revision I A "Loss of Reactor or Seconcary Coolant unit I." 'c6raidwood)
A.5.6 26wEP-I
. Revision IA. "Loss of Reactor or Seconaary Coolant Vnit 2."(BraiclW000)
A. 5.7 1 IBEP - 1. Revi slor, 1
. "Loss of Reactor or Secondary C o ol am Unit 1 " (Byron)
A.5 8 2BEP-1, Revision 1, 'Loss of Reactor or Secondary Coolant knit 2," (Byron)
A,5.9 SWOP CS-8. Revision 4 'Filling the Containment A510 BOP GS-6, Revision 8. "Filling the C=aiament Spray Additive Tank." (Byron)
F -
REVISION NO. : -0* 5-r C4 X h G.
C,152 :4772-'
COMMONWEALTH EDISON COMPANY additive flow ceases immediately, This is conservative, since it will minimize the amount of spray additive deiiverea to the cc ntainmerit Diameter:
8 tt Wall Thickness:
0.41 in Distance Between Instrument Taps :
2 x (6'6 1/2" - 3/4*)
Distance from Tap to Center Lire,
6161 1/20 -
31/4' Fill Pipe!
4" Schedule 44 Exhibit E NE P-12-02 W&W 5
ray Additive Tank.' (Bradwood) ray
4M "
=AX ha.
21 s2-~~-~=
COMMONWEALTH EDISON COMPANY CALCULATION NO.
- ATO-0356 PROJECT NO. 9135-196 PAGE NO A4 A.5.11 NDIT-BB-EXT-1218, 12/18196, 'CSA7 Level Indicator Loop Inaccuracies." (Byron 8 Braidwood )
A.5.12 Crane Technicai Paper Number410, 'Flow of Fluids Through Valves, Fittings, and Pipe,*
1988.
A.5. 13 Braiawood 182 Technical Specifications. Amendment 76 and Byron 1 &2 Technical Specifications. Amendment 83. Section LCO 3:6.2.2.
A.5.14 A.515 NDIT RSG-97-019. dated 6120197. Subject : Transmittal of design assure S&L calculation revisions dealing with tire CSAT level setpoin1s.
AX Calculations Calculation SRW-97-02741BYR97-165 Revision 1, "Containment Spray Additive Tank Level Switch Lo-Lo Setpoint Analysis' (Byron & Bmidwood)
A_8,1 Minimum Initial CSAT Level hrneer = % ever x Distance Between Taps 100 149.5'x 0_05 = 7.475" hiAriftm"mmor S h
^+tai - Uncertainty
_0
~so3
)alvi/i i 77
= 0.786(2(6'6'!' - 1'1.'))
=97928
=9.792ft-7.475 ft 12
= 9,169 ft 11- :e-97 11-17 P.05 EZhibit E NEP-x2-02 Rn'ision 5 Per References A.5.13, A.5.9. and A.5.10, the lowest CSAT fill level is 78.8% per level indicator (2)1 U-CS021. (Mote that the (2)1LT-CS021 upper and lower instrument taps are at the same elevation as the CSAT upper and lower tank taps per Reference A.5.14 reference drawings). This tanx level converted to distance above the (2)1LT-CS021 and CSAT instrument lower tap Is :
Per Reference 7,.5.11, the uncertainty of (2)1LI--CS021 is equal to +/-5%. Based on the (2)1LT-CS021 instrument span of 149 5' (distance between instrument taps per Design Input A.4 Y), the associated level uncertainty is :
The mininum initial CSAT level is equal to the total height above the (2)1LT-CS021 instrument and CSAT lower tap corresoonding to 78.60/c indicated level minus al,owance for instrument uncertainty :
onsforthe
FROM!
SGPP j CALCULATION NO, : AT A.5.2 CSAT Final Level Requirea to Deliver 2500 gallons N2OH Basea on previous revis!ons of this calculation. it is known that minimum sump pH requiremenis are satisfied if a minimum of 2500 gallons of NaOH are supplied to the Containment Spray system. The to!lowing calculation determines the highest level (lla m,.,m~m: above the CSAT lower tap to assure 2500 gallons cf NsOH are supplied:
2300 gallons x (ft'/?.48 gal) = 334.225 ft' 4
AJ Summary and Conclusions
=ax No. :
_~5 :: ;4a~;24
- i-1e-9
COMMONWEALTH EOISON COMPANY
-0356 PROJECT NO. 9135-196
= z (8 ft - b^ (0.41 /121n A" (9.169 ft - hr,,w.~,,,. m.rr) = 334=5 ft' 4
hSnnlmezrnum = 2.40 ft Exhibit E NEP-I2-02 Revision 5 The CSAT LO-2 level alartr must actuate at a maximum of 2.40 feet above the CSAT lower tap to assure a minimum volume of 2500 gallons NaOH is delivered to the Containment Spray System.
Reference A.5.14 determines the CSAT 1-t?-2 level setpoint necessary for alarm actufon at or below 2.40 feet above the CSAT lower tap including allowances for (2;1 LS-CS04SA/B instrument uncertainty, NaOH specific gravity uncertainty, and differences in tap elevation for the CSAT, level transmitters (2)1LT-CS021, and level transmitters (2)1LS-CS046A/B.
Per References A.5.5 througn A.5.8. the CS eductor spray addictive valves are closed when the CSAT LO-2 level is reached. Assuming that the operator closes the valves immediately and the system responos instantaneously {Assumption A.3.3). the final level in the CSAT will be at the LO-2 level
. This is conservative since this resu;ts in a smaller delivered Na0H volume.
in conclusion, calculation of sump minimum pH will be based on delivering a minimum of 2500 gallons of NaOH (30 wl% at 130), which is assured fry the CSAT 1.0-2 level setpoint per Reference A_5.14 acct.nng at or t:elow 2.40 ft 2oove the CSAT 'ower instrument tap.
~}rr,st3
- ~/v,/f 797 rFINAL]
P.36 Response to NRC Request for Additional Information BRAIDWOOD STATION UNITS 1 AND 2 Docket Nos. STN 50-456 and STN 50-457 License Nos. NPF-72 and NPF-77 and BYRON STATION UNITS 1 AND 2 Docket Nos. STN 50-454 and STN 50-455 License Nos. NPF-37 and NPF-66 Simplified Diagrams (Provided for Information Only)
ECCS-1, ECCS System, Revision 6 ECCS-2, ECCS Ring, Revision 6
SLACUUMULAMORS, 2M?2&0 MPNA1, 31-63 1 ~
(Ahn-33.5,'60P'~)
602-647pig
(;Alarms NOW) 700psig relief valves to Crant.
Initial Coin cooling on Large Break LOCA.
hviyatlopy.
S18808s auto up,
P-jl or ST
-9
--S-2600psidShuu 2500 Inid (,- 15 600-id,a sin, Modes 1-3 : Cannot close R118716's (will only injrr' MadeA-Aftut close I of the RH8716s (prevent lifting non-running R11 train mlief), bid pmver nuist he available & capable of 01wn tram tire b9C1J.
15001,,OSra4t, 1200 psid tp 41 800 psO 'a 6.50 goin CI*18110/8111 Close Rff'STLO-2 (46.79'0) 214 Channels
{with StSignal)
?T.)
200psidShwqlj 165 psid Cg 3 000 gpin 1251y,vid a~ 5000gpin CUUPUAU6 Close 1448psig and en 164.3 psig S Pressure. (with SISIgnal) v vifc.hes rim',, 164-7#,
are < 1448 #, with an St signal, V8114 & CV8116 illj4il Open (EIC)
B M P11 R WK Sol JU wu Hi: 96%
Lo: 90090 tech Specs: &9° Ln-P d6'%
Lo=.' :
&-7-"
1 ln~
NAIS :
d 012 switches)
IZR Press < 1829 pstg (2f4) v Steandine Press < 640 psig (213 on 114 SIG's) *9
- 4. Caw Hi-1 > 3.4 prig (2/3)
N Blocked < 11~41 9 Rate Sensitive 8
Ibcuti Bn Ji 01 CCSI, ECCS SYSTEM SEP 11, 20OZ REV 6 FOR TRAINING USE ONIY
c no longer used in the EPs ng Environmentally Qualified.
. SI8811 A & B Auto epee (RWST Lvl & Sit
- 2. Fstablkh CC flow to Rli HK's
- 3. Check adequate door water Ievei, close S18812A &
B 4 ail ptnnps discharge to cold legs A. CV8110, 8111, 8114 & 8116 close B. S18813,8814 & 8920 (SI recites) manually closed Brevants radioactive water to Rt5"ST)
C. R118716A & B (RH trains tie) Manually closed (Preens fault an one train starving bath trains)
D. S18807A, B & 8924 (CV to S0 manually opened iSingie lot train cnn supply ail ECCS Pompsi E. Open CV88(WA & S18904B (RH It, CV &
St Pi's) 5
. Reset SI signal to reposition valves 6
. CV 112D, E & S18806 mamoilly closed (Isolates all 0-paths from RWST to ECCS pumps 7
. At RWST Level Lo-3 alarm Open CS009AIB (Sump suctions), and Close CS0ol VB(RWSTsections)
HOT LEGAECIRCULATION (EP ES-1.4):
(Between 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> and 50 minutes and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and 10 mirnnes after SI, prepare for hot leg recite 4 boors and 50 minutes afiet ST]
'A' RH sod & C: lint Legs,'B' Rid to SI & C4 Pit',
ST to not Legs, CV to Cold I.,egs (Nlnv not be sure of whore the beak is located at)
I
. Close SI8809A & B 2
. Open RI78716A 3
. Open 518840 for RH to A &
C Hot Legs 4
. Stop A S1 Pump, close 518821 A and open 818802A 5
. Restart A St pump to A & D I lot Legs 6
. Perform same step for B SI Pump CS001 7
. ('lose S18835 of
+
114" Crimt Floor (377')
(Vlv #2 must be closed to open Vlv #1 Vlv#1 -4:~- Vlv#2 (Vlv #2 must be open to open Vlv #1 Vlv #I Vie #2 RESIDUAL HEAT REM()A'AL 518807 (To open either vlv, the other must be closed) 8 rV8116 CV811 9
CV8114 CVS DC TTY REASONS FOR HOT LEG RECIRC' I. Increases Core flow (assuming Cold Leg break)
- 2. Prevent plating out (due to boiling) which would:
a Block flow Channels
- b. Reduce heat transfer.
INJECTION PIIASE:
fd4'S I & A ccumul.tors gn to i,"old I.eg, I. CV Ptnnp, star
- 2. CVI12D&Eopen,then CVI12B&Cclose
- 3. SI8801A&Bopen
- 4. ST pumps start iniectmg thracuah S1882IA, B &
SI8835
- 5. RI I Pumps start injecting Ii
,, oe
- . S18909A & B 6_ CV Charging (CV 8105 & n I n,s ; close 7, i1 '8110&8lltcinsee kuc!Lv-2 8_
t V8114&at16c1 ._
'p-1 41,
- 9. CIAeeomv.ah+e=c ;>znut, :d-dartsign)mnjMa Normal COT !)-I, STo RCP Charging Seals 1
18801B CV 112D cV854(,
A&(-'
II O'(
LEGS C
SVAG
. VALVES (8):
(De-energize per Tech Specs)
Modes I-3 1
. 518806 open 2
. 518835 Open 3
. 518813 Open
- 4. SI8802A, B Closed Modes 1-4 (ILL. Injections) l. S18809A, B Open
- 2. 518840 Closed 6
ALARMS:
bevel High : 96.0%
I.ow: 90.0°,
Lo-2
- 46.7%
Lo-3
- 12.0°,
U P A
HOT ECCS-2, ECCS RING MAR 8, 2004, REV.
FOR TRAINING USE ONLY