ML17363A257
| ML17363A257 | |
| Person / Time | |
|---|---|
| Site: | 05200046 |
| Issue date: | 12/29/2017 |
| From: | Korea Hydro & Nuclear Power Co, Ltd |
| To: | Office of New Reactors |
| Shared Package | |
| ML17363A255 | List: |
| References | |
| MKD/NW-17-0381L | |
| Download: ML17363A257 (12) | |
Text
06.02.05-12_Rev.2 - 1 / 3 KEPCO/KHNP
REVISED RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION APR1400 Design Certification Korea Electric Power Corporation / Korea Hydro & Nuclear Power Co., LTD Docket No.52-046 RAI No.:
541-8724 SRP Section:
06.02.05 - Combustible Gas Control in Containment Application Section:
6.2.5 Date of RAI Issue:
02/21/2017 Question No. 06.02.05-12 This is a follow up question to KHNPs response to RAI 155-8167, Question 6.2.5-4, regarding passive autocatalytic recombiner (PAR) recombination rates.
10 CFR 52.44(c)(1) requires that a standard design certification applicant must ensure a mixed atmosphere in containment during design-basis and significant beyond design basis accidents.
A mixed atmosphere means that the concentration of combustible gases in any part of the containment is below a level that supports combustion or detonation that could cause loss of containment integrity.
APR1400 Design Control Document (DCD) Tier 2, Section 6.2.5 credits the passive autocatalytic recombiners (PAR) with meeting the above criteria.
However, in DCD Tier 1, Table 2.11.4-1, Containment Hydrogen Control System ITAAC, there is insufficient information to determine that the containment hydrogen control system design meets the above criteria. In DCD Tier 2, Table 6.2.5-1, Location of PARs and His, PAR and hydrogen igniters (HI) locations in containment are provided. This information should either be included in Tier 1, Table 2.11.4-1, or a link to Tier 2, Table 6.2.5-1 should be provided in Tier 1, Table 2.11.4-1.
Also, DCD Tier 2, Table 6.2.5-1 describes the PARs as small, middle, large. The actual PAR recombination rates which form the basis of the hydrogen containment analysis should be provided in the DCD.
The response stated that the equation for the recombination rate for the large (FR1-1500) PARs has the two coefficients, A and B. The staff's review indicates that these coefficients, A and B, should be larger. These coefficients were deduced by comparing the recombination rate that is predicted by the formula to the performance specifications published for an AREVA PAR.
06.02.05-12_Rev.2 - 2 / 3 KEPCO/KHNP
KHNPs response to RAI 472-8564, Question 6.2.5-11, confirmed the larger coefficients above were used by KHNP in their analyses. This is in agreement with the coefficients used in staff's MELCOR confirmatory calculation.
In the original RAI 155-8167, question 6.2.5-4, staff also requested the following:
DCD Tier 2, Table 6.2.5-1 describes the PARs as small, middle, large. The actual PAR recombination rates which form the basis of the hydrogen containment analysis should be provided in the DCD, either:
G Into both Tier 2, Table 6.2.5-1 and Tier 1, Table 2.11.4-1, or G
Into just Tier 2, Table 6.2.5-1, with a link to Tier 2, Table 6.2.5-1 being provided in Tier 1, Table 2.11.4-1.
Please provide the recombination rates of the three sizes of PARs which establish the capacity of the containment hydrogen control system.
Response - (Rev. 2)
The reference data for hydrogen depletion rates by PAR size are provided in the table below.
They will be added to DCD Tier 2 as Table 6.2.5-3.
Reference data of hydrogen depletion rate by PAR size Condition Size Hydrogen 4 v/o (percent by volume)
Hydrogen 8 v/o (percent by volume)
Small 0.9 kg/hr 1.8 kg/hr Medium 1.8 kg/hr 3.6 kg/hr Large 4.0 kg/hr 8.0 kg/hr The hydrogen depletion rates are based on the hydrogen depletion equation from the MAAP manual. The initial condition is of 1.5 bar at 60oC.
In addition, a link to Tier 2, Table 6.2.5-1 in Tier 1, Table 2.11.4-1 (regarding the location of PARs and HIs provided in response to RAI 155-8167, question 6.2.5-4) will be deleted. The PARs and HIs locations will be provided in Tier 1 Table 2.11.4-1 at the qualitative level. The PAR depletion rates will not be provided in Tier 1. The depletion rates are derived from proprietary data and are not appropriate for Tier 1. The hydrogen depletion rates are determined to meet or exceed RG 1.7 criteria of a hydrogen concentration of 10 percent, (by volume), in the containment and IRWST, as discussed in DCD Tier 1 Section 2.11.4.1 and Table 2.11.4-3.
06.02.05-12_Rev.2 - 3 / 3 KEPCO/KHNP
DCD Tier 1 Table 2.11.4-1 will be revised to address the hydrogen depletion rates and location criteria. DCD Tier 1 DCD Table 2.11.4-3 will be revised to address the location and performance criteria. Tier 2 Table 14.3.4-2 will be revised to address the PAR and HI locations.
Impact on DCD DCD Tier 2, Subsections 6.2.5.2.1 and 6.2.8 and Table 14.3.4-2 will be revised and Table 6.2.5-3 will be added as indicated in Attachment 1.
DCD Tier 1, Tables 2.11.4-1 and 2.11.4-3 will be revised as indicated in the Attachment 2.
Impact on PRA There is no impact on the PRA.
Impact on Technical Specifications There is no impact on the Technical Specifications.
Impact on Technical/Topical/Environmental Reports There is no impact on any Technical, Topical, or Environmental Report.
Table 6.2.1-35 Letdown Heat Exchanger and Valve Subcompartments Vent Path Description............................................................................... 6.2-396
Table 6.2.1-36 Mass and Energy Release Data........................................................ 6.2-398
Table 6.2.1-37 Stored Energy Sources..................................................................... 6.2-403
Table 6.2.1-38 Primary Side Resistance Factors Used in FLOOD3 Code.............. 6.2-433
Table 6.2.1-39 Blowdown and Reflood Mass and Energy Release for the Minimum Containment Pressure Analysis...................................... 6.2-434
Table 6.2.2-1 Input Values Used in CSS Evaluation Calculations........................ 6.2-438
Table 6.2.2-2 Containment Spray System Design Parameters.............................. 6.2-439
Table 6.2.2-3 Containment Spray System Failure Modes and Effects Analysis........................................................................................... 6.2-441
Table 6.2.2-4 Containment Spray System Display Instrumentation...................... 6.2-446
Table 6.2.2-5 Mass Mean Diameter....................................................................... 6.2-447
Table 6.2.4-1 List of Containment Penetrations and System Isolation Positions........................................................................................... 6.2-448
Table 6.2.5-1 Location of PARs and HIs............................................................... 6.2-458
Table 6.2.5-2 Hydrogen Monitoring System Failure Modes and Effects Analysis........................................................................................... 6.2-460
Table 6.3.1-1 Responses of APR1400 to TMI Action Plan..................................... 6.3-35
Table 6.3.1-2 Responses of APR1400 to Generic Safety Issues.............................. 6.3-36
Table 6.3.1-3 Responses of APR1400 to Generic Letters....................................... 6.3-37
Table 6.3.2-1 SIS Component Parameters............................................................... 6.3-38
Table 6.3.2-2 Safety Injection System Failure Modes and Effects Analysis........... 6.3-41
Table 6.3.2-3 Safety Injection System Head Loss Requirements............................ 6.3-55
Table 6.3.2-4 Safety Injection System Flow Delivery to RCS (1)............................ 6.3-56
Table 6.4-1 The Accident Radiation Source Description and Radiation Shielding Design for MCR and TSC................................................. 6.4-15
Table 6.4-2 MCR and TSC Doses from Design Basis Accidents......................... 6.4-16
Table 6.4-3 Amounts of Hazardous Chemicals Stored Onsite............................. 6.4-17
Table 6.5-1 Engineered Safety Features Filter Systems - Component Specification...................................................................................... 6.5-24
Table 6.2.5-3 Performance Criteria for Depletion Rates of PARs APR1400 DCD TIER 2 ix 5HY
Reference Data of Hydrogen Depletion Rate by PAR Size RAI 541-8724 Question 06.02.05-12_Rev.1 RAI 541-8724 Question 06.02.05-12 5$,4XHVWLRQB5HY
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The PARs in the containment and inside the IRWST vent stack, and the HIs in the containment are designed to withstand severe accident conditions. The PARs and HIs provide reasonable assurance that the equipment can perform its identified function during severe accident conditions as described in Section 19.2.
PARs are considered a 15 percent efficiency reduction for iodine vapor and 10 percent efficiency reduction for cable fire. Thus, a total 25 percent efficiency reduction for the PAR was considered for capacity reduction. The HIs include a consideration of the combustion model of the MAAP computer code.
The PARs and HIs are designed to prevent any significant pocketing of hydrogen in order to minimize the potential for localized hydrogen detonation.
The PARs and HIs are able to withstand the effects of their own operations and are designed to provide reasonable assurance that equipment necessary for achieving and maintaining a safe shutdown of the plant and containment integrity are capable of performing their functions during and after their exposure to hydrogen burning.
The PARs and HIs are located throughout the containment open volumes and compartments.
The following location criteria are used:
- a.
Flow path requirements
- b. Consideration of enclosed spaces
- c.
Equipment performance efficiency
- d. Installation and maintenance
- e.
Consideration of dynamic effect For the surveillance test of PARs, a sample of the PAR cartridges or plates is selected and removed from each PAR. Surveillance bench tests are performed on the removed specimens to confirm continued satisfactory performance. The HIs are capable of attaining the surface temperature that is sufficient for igniting hydrogen gases under any environmental conditions including CS actuation. The HI configuration, including possible spray shields, is supported by combustion test data.
The performance criteria for depletion rates of PARs is provided in Table 6.2.5-3.
APR1400 DCD TIER 2 6.2-75 5HY
The reference data of hydrogen depletion rate by PAR size for PAR surveillance test is provided in Table 6.2.5-3. The reference data is based on the hydrogen depletion equation from MAAP manual (Reference 43) and the initial condition is of 1.5 bar and 60oC.
RAI 541-8724 Question 06.02.05-12_Rev.1 RAI 541-8724 Question 06.02.05-12 5$,4XHVWLRQB5HY
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- 39. ASME Section III, Division 1, Article NE 2300, Fracture Toughness Requirements for Material, The American Society of Mechanical Engineers.
- 40. NUREG-0800, Section 6.2.1.2, Subcompartment Analysis, Rev. 3, U.S. Nuclear Regulatory Commission, March 2007.
- 41. NRC RG 1.141, Containment Isolation Provisions for Fluid Systems.
- 42. APR1400-E-P-NR-14003-P(Proprietary)&NP(Non-Proprietary) Severe Accident Analysis Report, Rev. 1 KHNP, February 2017.
- 43. FAI/12-0005, "MAAP 4.0.8 Transmittal Document," Electric Power Research Institute, February 2012.
APR1400 DCD TIER 2 6.2-93 5HY
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APR1400 DCD TIER 2 Table 6.2.5-2 (6 of 6)
Name/Valve No.
Potential Failure Mode Plant Condition Symptoms and Local Effect Including Dependent Failure Method of Detection Inherent Compensating Provision Remarks and Other Effects
- 6. Channel B containment monitor discharge to containment CM-010 a) Fails to open on demand Detection of hydrogen in containment building x No safety-related impact on plant x Isolation is achieved by redundant valve Valve information:
x Valve position indication in MCR Isolation is achieved by redundant containment isolation valve (CM-009) x Normally closed x Fail closed b) Fails to close on demand x Loss of electrical power x Receipt of high containment pressure signal x Receipt of low pressurizer pressure signal x No safety-related impact on plant x H2 monitoring line is formed in the closed loop H2 monitoring line is formed in the closed loop 6.2-465 5HY
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Reference Data for Hydrogen Depletion Rate by PAR Size 8 v/o 3.6 8.0 4.0 RAI 541-8724 Question 06.02.05-12_Rev.1 RAI 541-8724 Question 06.02.05-12 5$,4XHVWLRQB5HY
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APR1400 DCD TIER 2 14.3-44 Table 14.3.4-2 (7 of 7)
Item #
Tier 1 Reference Design Features Tier 2 Reference 2-47 2.11.4 Design Description ITAAC #3 The containment hydrogen control system (CHCS) is non-safety-related system. The CHCS is used to maintain hydrogen gas concentration in containment at a level that precludes an uncontrolled hydrogen and oxygen recombination within containment following beyond-design-basis accidents.
The CHCS consists of the passive autocatalytic recombiners (PARs) and hydrogen igniters (HIs). The PARs and HIs are designed to control and allow adiabatic controlled burning of hydrogen at fairly low concentration in containment and in-containment refueling water storage tank (IRWST) from exceeding 10 volume percent during a degraded core accident with 100 percent fuel clad metal-water reaction.
6.2.5 19.1.3 19.2.3 2-48 2.11.4 ITAAC #3 The CHCS provides PARs complemented by HIs to control the containment hydrogen concentration for beyond-design-basis accidents.
6.2.5 19.1.3 19.2.3 2-49 2.11.4 ITAAC #3.a At least 30 PARs and 8 hydrogen igniters are provided inside containment.
6.2.5 19.2.3 2-50 3.2
- a.
The UHS provides the capability to reject the heat under normal and accident conditions (safe shutdown or post-accident) assuming a single active failure concurrent with a loss of offsite power.
9.2.5 19.1.3 5HY
2-53 2.11.4 A report exists and concludes that the hydrogen depletion 6.2.5 ITAAC #3.b rates for each installed PAR and HI will maintain containment 19.2.3 hydrogen concentration of less than or equal to 10 percent by volume.
RAI 541-8724 Question 06.02.05-12_Rev.1 5$,4XHVWLRQB5HY
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APR1400 DCD TIER 1 2.11-59
Table 2.11.4-1 Containment Hydrogen Control System Components List Component Name Item No.
Location(1)
ASME Section III Class Seismic Category Class 1E/Harsh Envir. Qual.
Display/
Control at MCR Display/
Control at RSR Control Signal Active Safety Function Loss of Motive Power Position Passive Autocatalytic Recombiner HR01A/01B ~
HR15A/15B Containment I
-/-
-/-
-/-
No Hydrogen Igniter HI01 ~ HI08 Containment I
No/-
Yes/Yes Yes/Yes No Containment Temperature Element CM-TE-031A Containment I
Yes/Yes Yes/No Yes/No No (1)
Location of PARs and His are provided in DCD Tier 2, Table 6.2.5-1 (2)
Dash (-) indicates not applicable.
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Deleted Replaced with A in next page.
RAI 541-8724 Question 06.02.05-12_Rev.1 RAI 541-8724 Question 06.02.05-12 (1/3)
RAI 541-8724 - Question 06.02.05-12_Rev.2
APR1400 DCD TIER 1 Table 2.11.4-1 Containment Hydrogen Control System Components List Component Name Item No.
General Location ASME Section III Class Seismic Category Class 1E/Harsh Envir. Qual.
Display/
Control at MCR Display/
Control at RSR Control Signal Active Safety Function Loss of Motive Power Position Large PAR HR01A/01B ~
HR04A/04B Containment Dome Area I
-/-
-/-
-/-
No HR05A/05B ~
HR06A/06B Steam Generator Compartment HR07A/07B ~
HR08A/08B Upper Compartment Medium PAR HR09A/09B ~
HR10A/10B Inside IRWST HR11A/11B ~
HR13A/13B Lower Compartment Small PAR HR14A/14B Reactor Detector Tube Compartment, Cavity Region HR15A/15B Regenerative heat exchanger and Pressurizer compartment Hydrogen Igniter HI01 Cavity access area I
No/-
Yes/Yes Yes/Yes No HI02 Regenerative heat exchanger Room HI03~HI04 Pressurizer Compartment HI05~HI08 Steam Generator Compartment Containment Temperature Element CM-TE-031A Containment I
Yes/Yes Yes/No Yes/No No (1) Dash (-) indicates not applicable.
RAI 541-8724 Question 06.02.05-12_Rev.1 A (2/3)
RAI 541-8724 - Question 06.02.05-12_Rev.2
APR1400 DCD TIER 1 2.11-61
Table 2.11.4-3 (1 of 2)
Containment Hydrogen Control System ITAAC Design Commitment Inspections, Tests, Analyses Acceptance Criteria
- 1.
The functional arrangement of the CHCS is as described in the Design Description of Subsection 2.11.4.1 and in Table 2.11.4-1 and as shown in Figure 2.11.4-1.
- 1.
Inspection of the as-built CHCS will be conducted.
- 1.
The as-built CHCS conforms with the functional arrangement as described in the Design Description of Subsection 2.11.4.1 and in Table 2.11.4-1 and as shown in Figure 2.11.4-1.
- 2.
The seismic Category I components identified in Table 2.11.4-1 withstand seismic design basis loads without loss of safety function.
- 2.
Inspections will be performed to verify that the as-built seismic Category I components are located in the seismic Category I structure.
- 2.
The as-built seismic Category I components identified in Table 2.11.4-1 are located in a seismic Category I structure.
- 3.
The CHCS provides PARs complemented by HIs to control the containment hydrogen concentration for beyond design basis accidents.
3.a Inspection for the number of PARs and hydrogen igniters will be performed.
3.a At least thirty PARs and eight hydrogen igniters are provided inside containment.
3.b Operability testing will be performed on the PARs and hydrogen igniters.
3.b A report exists and concludes that the PAR depletion rate for each installed PAR is equal to or greater than that of predetermined PAR hydrogen depletion capacity.
For hydrogen igniters, the surface temperature exceeds 1,700 °F
- 4.
The electrical power for HIs is supplied from the Class 1E division. On loss of offsite power and failure of the emergency diesel generator to start or run, the HIs have the alternate power supply from the alternate alternating current (AAC) generator. Also, HIs are powered by battery back-up.
- 4.
Tests will be performed on the as-built HIs.
- 4.
The as-built HIs listed in Table 2.11.4-1 are powered from class 1E division, the emergency diesel generator, the AAC generator, and DC battery.
5.a Controls exist in the MCR to start and stop the HIs identified in Table 2.11.4-1.
5.a Tests will be performed using the controls in the MCR.
5.a Controls in the as-built MCR start and stop the hydrogen igniters listed in Table 2.11.4-1.
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RAI 541-8724 Question 06.02.05-12_Rev.1 A report exists and concludes that the hydrogen depletion rates for each installed PAR and HI will maintain containment hydrogen concentration of less than or equal to 10 percent by volume.
and their general location,as described in Table 2.11.4-1, RAI 541-8724 - Question 06.02.05-12_Rev.2 (3/3) the installed PARs and HIs will maintain containment hydrogen concentration, both locally and globally, of less than or equal to 10 percent by volume, or avoids DDT or detonation in order to maintain containment integrity.
RAI 541-8724 Question 06.02.05-12_Rev.2