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.AR LOIT Systems: Welch's Highlighted Notes > .AR CH-CVCS/PHIX/BAC/Gas Stripper (Welch's Highlighted Notes) > Flashcards

.AR CH-CVCS/PHIX/BAC/Gas Stripper (Welch's Highlighted Notes) Flashcards

1
Q

CVCS Design Bases / Functions:

  • ?…
  • ?…
A

CVCS Design Bases / Functions:

  • Compensate for small amounts of RCS leakage.
    • One charging pump has capacity for leaks in small RCS lines (instrument and sample lines).
  • Continuous measurement of RCS fission product activity (RU-155)
  • Maintains Tech Spec activity limits assuming 1% failed fuel condition at 100% RTP.
  • Refueling Water Tank (RWT): source of borated water for SI following a LOCA.
    • 20 minutes (plus 10% margin) of full flow of all ESF pumps prior to reaching RAS.
  • RWT ensures adequate containment sump level to support ECCS recirculation and loss of inventory due to the following:
    • Containment sub-compartments and reservoirs due to containment spray operation.
    • Areas outside containment due to ECCS leakage.
    • Minimum NPSH for ECCS pumps is maintained.
  • Receives, stores, and separates borated water waste for reuse and/or discharge to LRS.
  • Auxiliary spray (Final stages of shutdown and to allow for cooling of the PZR).
  • SFP make-up.
  • Receive discharges from drains and relief valves from the RCS, ECCS, and SDC (RDT/EDT).
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2
Q

CVCS Flow Balance:

Charging flow = Letdown flow + Bleed-off flow (with no RCS leakage).

…?

Letdown limitations:

  • ?…
A

CVCS Flow Balance:

Charging flow = Letdown flow + Bleed-off flow (with no RCS leakage).

Charging Flow (88 gpm)(2 CPs @ 44gpm/CP) and Bleed-off flow (12 gpm)(2-3 gpm/RCP) and Letdown (76 gpm) - constant PZR and VCT level

Letdown limitations:

  • 150 gpm – max flow

140°F – max temp

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3
Q

Delay Coils:

  • ?…
A

Delay Coils:

  • Allow time for N-16 to decay by reducing the velocity.
  • Single 2” letdown line splits into two lines (12’ long, 16” diameter). Lines come back together into one letdown line.
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4
Q

Letdown Line to RHX Valve (CHB-UV-515):

  • Auto closure:
    • ?…​
    • ?…
  • ?…Override avail?
  • ?…
A

Letdown Line to RHX Valve (CHB-UV-515):

  • Auto closure: (SI-Hi)
    • SIAS (B train)
    • High RHX Out Temp 413°F (TS-221)
  • SIAS override available
  • AOP directs jumper if TS failed (no override for Hi temp)
  • LOCAL/REMOTE switch (App. R)
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5
Q

Letdown Line to RHX CIV (CHA-UV-516):

  • CIV?
  • Auto closure:
    • ?…
    • ?…
  • Override?…
A

Letdown Line to RHX CIV (CHA-UV-516):

  • CIV
  • Auto closure: (SI-CI)​
    • SIAS (A train)
    • CIAS (A train)

Override available

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6
Q

Outside CTMT Letdown Isolation Valve (CHB-UV-523):

  • CIV?
  • Auto closure:
    • ?…
    • ?…
  • Override?…
  • ?…
A

Outside CTMT Letdown Isolation Valve (CHB-UV-523):

  • CIV
  • Auto closure: (CI-Hi)
    • CIAS (B train)
    • High LDHX outlet temp 135°F (T-224)
  • CIAS override (HS to close)
  • Hi Temp override (take HS to open)
    • Used for failed TS
    • No white override light
    • If hi temp override does not work, AOP directs jumper install (T-Mod)
    • Hi Temp override does NOT affect CIAS auto closure (remains operable for LCO 3.6.3)
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7
Q

Letdown Control Valves (LV-110P, LV-110Q):

  • Controlled by ?…
  • Fail closed AOVs
  • Controller power?...
  • VPI?…
  • Placed in service?…
A

Letdown Control Valves (LV-110P, LV-110Q):

  • Controlled by PLCS
  • Fail closed AOVs
  • NNN-D11 (Controller power)
  • NKN-D42 (VPI)
  • If both in-service > 1200 psia, may lift LD relief valve
    • Place 2nd valve in-service < 1050 psia
    • Remove 2nd valve from service > 1000 psia
    • OOS valve is locally isolated
  • 30-135 gpm in Auto (prevent flashing and IX channeling)
  • 0-150 gpm in manual control
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8
Q

Letdown Backpressure Control Valves (PV-201P/201Q):

  • Prevents boiling / flashing in …?
  • NOP: how many valves selected?…
A

Letdown Backpressure Control Valves (PV-201P/201Q):

  • Prevents boiling / flashing in the letdown HX.
  • 375 psig: Normal setpoint for upstream pressure (PT-201)
  • Auto closes on High LDHX outlet temp 148°F (T-224)
    • Manual control will override the temp interlock.
  • Fails closed on loss of power to controller (NNN-D12)
    • Transfers to manual upon power restoration.
  • NKN-D42 (VPI)
  • Fail closed AOVs
  • NOP: one valve is selected, other is isolated locally
    • Place 2nd valve in-service < 750 psia
    • Remove 2nd valve from service > 1000 psia

Same train letdown control valve and backpressure control valve should be selected.

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9
Q

Letdown Control Valve Bypass (CHN-HV-526):

  • ?…

Letdown Intermediate Pressure Relief (PSV-345)

  • ?…
A

Letdown Control Valve Bypass (CHN-HV-526):

  • SOV
  • Fails closed (NK)
  • ~ 1/2 gpm bypass flow around letdown control valves
  • Use when placing letdown in-service.
  • Bypass for 4 min if isolated > 22 min and RCS temp is > 130°F
  • Two-position HS: OPEN - LOCK CLOSE (key switch)

Letdown Intermediate Pressure Relief (PSV-345)

  • Protects piping between LDCVs and BPCVs against a flow blockage downstream of the LDHX.
  • Located downstream of the LDCVs.
  • Opens at 600 psig.
  • Relieves to the EDT
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10
Q

Letdown Purification Filters:

  • ?

Boronometer and RM FCV (FV-204):

  • Fails open:
    • ?…
    • ?…
  • Maintains ~ # gpm flow.

Boronometer:

  • ?…
A

Letdown Purification Filters:

  • Removes particulates. Prevent clogging Letdown IXs.
  • One filter is normally in service.

Boronometer and RM FCV (FV-204):

  • Fails open:
    • Loss of Air
    • Loss of Power (Non-class DC power / NKN)
  • Maintains ~ 8 gpm flow.

Boronometer:

  • Internals removed. Vessel remains in place.
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11
Q

{…not highlighted in Welch’s notes…}

Boronometer and RM Bypass Valve (CHE-UV-521):

  • Fails to which position?…

Low Pressure Letdown Relief Valve (PSV-354):

  • Protects what SSC?…
  • ?…
A

{…not highlighted in Welch’s notes…}

Boronometer and RM Bypass Valve (CHE-UV-521):

  • Fails to the BYPASS position:
    • Loss of Air
    • Loss of Powe (Non-class DC power)
    • High LDHX temp 135°F (TS-224)
  • Must be reset after loss of power or hi temp.

Low Pressure Letdown Relief Valve (PSV-354):

  • Protects the boronometer from over pressure.
  • Located downstream of the BPCVs.
  • Opens at 200 psig
  • Relieves to the EDT.
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12
Q

Letdown Ion Exchangers Bypass Valve (UV-520):

  • Protects which SSC?…
  • ?…
A

Letdown Ion Exchangers Bypass Valve (UV-520):

  • Protects the resin from damage due to excessive temperature.
  • Fail to the BYPASS position:
    • High LDHX Out Temp 135°F (TS-224)
    • Loss of air
    • Loss of power (NK)
  • Remains in bypass after loss of power or hi temp. Re-position with the HS.
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13
Q

Process Radiation Monitor (RU-155D):

  • Detect what?…
  • Alarm: at # % ?
A

Process Radiation Monitor (RU-155D):

  • Detect FEFs.
  • Alarm: 1% failed fuel dose rate
  • E-plan required RU (Unusual Event if in Alarm)
  • Constant reading due to 10 mr/hr source
  • Process rad monitor (however, it is located next to the letdown piping and functions like an area monitor)
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14
Q

{…not highlighted in Welch’s notes…}

VCT Inlet Valve (UV-500):

  • ?…
  • ≥ 60% VCT level (227): ?…
  • ≤ 58% VCT level (227): ?…
A

{…not highlighted in Welch’s notes…}

VCT Inlet Valve (UV-500):

  • Fails to the VCT Position on:
    • Loss of air
    • Loss of power (NK)
  • After a loss of power, the valve must be reset with the HS.
  • ≥ 60% VCT level (227): diverts to PHIX position and on to the gas stripper (if aligned) and then to the HUT.
  • ≤ 58% VCT level (227): resets to the VCT position.
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15
Q

{…not highlighted in Welch’s notes…}

Purification Ion Exchangers (D01A, D01B, and D02):

  • 150 gpm max flow… why?…
  • 140°F max…why?…
  • ?…
A

{…not highlighted in Welch’s notes…}

Purification Ion Exchangers (D01A, D01B, and D02):

  • 150 gpm max flow (channeling)
  • 140°F max (damage resin)
  • One IX normally in service (removing particulate, ionic impurities, and radionuclides)
  • One IX placed in service as needed to control RCS lithium concentration for pH control. (Delith)
  • Deborating IX used at EOL to remove remaining RCS boron.
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16
Q

VCT Outlet Valve (UV-501):

  • ?…
  • 501 Auto Features:
    • Closes on…?
    • Opens after the LO-LO level…?
    • Opens if VCT LO-LO Level…?
  • Must be able to close CHN-UV-501 to maintain what…?
A

VCT Outlet Valve (UV-501):

  • Isolates VCT from Charging Pump suctions so alternate suction paths can be aligned from the MCR.
  • Powered from PHA-M35.
    • Backup breaker on NHN-M72.
  • Local controls at NHN-M72
  • 501 Auto Features:
    • Closes on VCT LO-LO level of 5% (LS-227)
    • Opens after the LO-LO level clears (15%)
    • Opens if VCT LO-LO Level is not present and UV-536 is closed.
  • Must be able to close CHN-UV-501 to maintain boration flow paths functional. (TRM bases)
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17
Q

Charging Pump support systems:

Seal Water System

  • Prevents leakage of RCS from…?
  • ?…
  • Pump operation without seal lube water is allowed under emergency conditions for ≤ #? hours.
A

Charging Pump support systems:

Seal Water System

  • Prevents leakage of RCS from the pump seals.
  • Seal water pump auto starts when CHP starts.
  • Pump is run for 10 minutes prior to CHP start to verify proper seal lube pressure
  • Prolongs life of the packing.

Pump operation without seal lube water is allowed under emergency conditions for ≤ 50 hours.

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18
Q

{…not highlighted in Welch’s notes…}

Charging Pump support systems:

Suction Stabilizers

  • ?…

Charging Pump Vent Receiver Tank

  • ?…

Discharge Pulsation Dampeners

  • ?…
A

{…not highlighted in Welch’s notes…}

Charging Pump support systems:

Suction Stabilizers

  • Absorbs pressure surges in the pump suction piping.
  • 19 psig N2 charged bladder and a flow deflector.
  • Ruptured bladder has caused gas binding of the pumps.

Charging Pump Vent Receiver Tank

  • Provides a vent path for each pump to minimize the effects of a common mode failure of the Charging Pumps

Discharge Pulsation Dampeners

  • 1500 psig N2 charged bladder, a spring loaded poppet and a fixed flow diversion baffle.
  • Diversion baffle, poppet and bladder interface to absorb pressure surges.
  • Spring loaded poppet compensates for small pressure changes.
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19
Q

Charging Pump support systems:

Lube Oil System

  • ?…

Charging Pump Oil Drain Tank

  • Collects oil leak-off from…?
A

Charging Pump support systems:

Lube Oil System

  • Shaft driven pump
  • Relief valve maintains pressure normally 30-35 psig.
  • Low pressure alarm at 18 psig (NO pump trip)
  • ARP directs stopping the pump within 60 seconds if low lube oil pressure.

Charging Pump Oil Drain Tank

Collects oil leak-off from Charging Pump plunger box assembly.

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20
Q

Charging Pumps (CHPs) (A, B, E):

  • PDPs or CPs?
  • # gpm at # psig
  • Power Supplies:
    • A pump: ?
    • B pump: ?
    • E pump: either ? or ? (Swap breaker and transfer local disconnect switch)
A

Charging Pumps (CHPs) (A, B, E):

  • Positive displacement pumps
  • 44 gpm at 2375 psig
  • Power Supplies:
    • A pump: PGA-L31
    • B pump: PGB-L32
    • E pump: either PGA-L35 or PGB-L36 (Swap breaker and transfer local disconnect switch)
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21
Q

Charging Pumps suction paths:

  • ?…
  • ?…

Charging Pumps discharge paths:

  • ?…
  • ?…
A

Charging Pumps suction paths:

  • VCT through UV-501
  • Makeup system through UV-210X and/or 210Y
  • BAMP direct discharge through UV-514
  • RWT gravity feed through HV-536
  • Alternate suction from the RWT through V-327

Charging Pumps discharge paths:

  • Charging Header
  • HPSI Train A Cold Leg Injection Lines
  • HPSI Train B Hot Leg Injection Line
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22
Q

Auto-After-Start (Red Flagged) [Manually Started]:

  • ?…

Auto-After-Stop (Green Flagged) [Auto]

  • ?…
A

Auto-After-Start (Red Flagged) [Manually Started]:

  • Pump will NOT respond to PLCS.
  • Trips:
    • Low suction pressure
    • Motor overload
    • BOP ESFAS load shed
  • Must be manually restarted after low pressure or overload trip.

Auto-After-Stop (Green Flagged) [Auto]

  • Allows pump to be operated by PLCS.
  • Breaker will anti-pump if tripped on low suction pressure, overload, always running on a LOOP or LOP, normal running on a LOP.
  • Start signal is from PLCS.
  • Clear Anti-pump by taking HS to STOP and then back to AUTO.
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23
Q

CH Pump low suction pressure protection:

  • ?…

App. R Disconnect Switch (B Pump ONLY):

  • Switch located on PGB-L#?
  • ?…
  • Do low suction pressure and overload trips remain functionoal?…
A

CH Pump low suction pressure protection:

  • Protect from cavitation damage.
    • Trips ≤ 13 psia
    • Resets ≥ 14 psia
  • Take pump HS to STOP to clear the trip.
  • A and B have one pressure switch each.
  • E has two pressure switches (1 per train)

App. R Disconnect Switch (B Pump ONLY):

  • Switch located on PGB-L32.
  • Pump controlled locally at the breaker.
  • Low suction pressure and overload trips remain functional
  • PLCS / BOP-ESFAS auto features no longer functional
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24
Q
  • (Charging Pumps on a…)* SIAS/CSAS (Mode 1):
  • ?…
A

(Charging Pumps on a…) SIAS/CSAS (Mode 1):

  • Pumps are not tripped by SIAS or CSAS
  • Load sequencer prohibits AUTO start for 40 seconds.
  • After 40 seconds, pumps will start in AUTO as demanded by PLCS.
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25
Q
  • (Charging Pumps on a…)* LOP AND SIAS (Mode 2):
  • ?…
A

(Charging Pumps on a…) LOP AND SIAS (Mode 2):

  • Charging pumps are Load Shed.
  • Load sequencer prohibits AUTO start for 40 seconds after DG breaker closes.
  • After 40 seconds, pumps auto starts as required by PLCS.
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26
Q
  • (Charging Pumps on a…) ​*LOP NO SIAS (Mode 3):
  • ?…
A

(Charging Pumps on a…) ​LOP NO SIAS (Mode 3):

  • Running charging pumps stopped and in Anti-Pump.
    • Always running pump due to locked in start signal from PLCS (NKN-D42 never lost power)
    • Normally running pump due to locked in start signal from PLCS (NNN-D11 never lost power)
  • Pumps must be manually restarted by taking HS to STOP.
  • LOP only impacts same train pump(s). (PBA LOP will NOT impact the B charging pump.)
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27
Q
  • (Charging Pumps on a…)* ​Loss of Offsite Power (LOOP):
  • ?…
A

(Charging Pumps on a…) Loss of Offsite Power (LOOP):

  • Always running pump will be in anti-pump condition due to locked in start signal from NKN-D42
  • Normal and Standby will be controlled by PLCS
    • NNN-D11 momentarily lost power and removed the start signal

This assumes instant loss of off-site with no coastdown, this is only way to “momentarily” de-energize NNN-D11. D11 restored once DG ties onto PBA-S03. If coastdown occurs, NNN-D11 will remain energized from the Turbine while the DG is starting.

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28
Q

Pressurizer Level Control System (PLCS):

Normally Running

  • Stops …?
  • Restarts…?

Standby

  • Starts …?
  • Stops …?
A

Pressurizer Level Control System (PLCS):

Normally Running

  • Stops +15% PZR Level deviation
  • Restarts +14% PZR Level deviation

Standby

  • Starts -23% PZR Level deviation
  • Stops -14% PZR Level deviation
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29
Q

Charging Header Isolation Valve (CHA-HV-524):

  • CIV?
  • Motive power from ?
  • Power removed to ensure what?…
A

Charging Header Isolation Valve (CHA-HV-524):

  • CIV
  • Motive power from PHA-M35 (normally de-energized)
  • Indication power from PHA-M33
  • Power removed to ensure aux spray is available
    • TRM SR for Aux Spray
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30
Q

Charging Line Isolation Valve (CHE-HV-239):

  • Prevents the loss of aux spray if ?…
  • ?…
A

Charging Line Isolation Valve (CHE-HV-239):

  • Prevents the loss of aux spray if PDV-240 fails open
    • Not enough back pressure for spray
  • Fails closed [Loss of air or power (NKN)]

Over-voltage relay will de-energize control power to the valve on a high voltage condition. Disconnect switch must be opened and reclosed to reset the relay.

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31
Q

Charging Line Backpressure Control Valves (PDV-240):

  • Maintains charging header backpressure @ # psid?
  • ?…
A

Charging Line Backpressure Control Valves (PDV-240):

  • Maintains charging header backpressure (~105 psid)
    • Ensures seal injection and aux spray flow.
  • Modulates based on Charging Line Backpressure Controller (PDIC-240) output.
  • Controller power: NNN-D12
  • Fails closed [Loss of air or power (NKN) or NNN-D12]

Over-voltage relay will de-energize control power to the valve on a high voltage condition. Disconnect switch must be opened and reclosed to reset the relay.

32
Q

{…not highlighted in Welch’s notes…}

Spring-Loaded Bypass Check Valve (CHE-V435):

  • ?…
A

{…not highlighted in Welch’s notes…}

Spring-Loaded Bypass Check Valve (CHE-V435):

  • Maintains charging flow and sufficient backpressure to supply seal injection and aux spray if PDV-240 and/or HV-239 fail closed.
  • Opens at 200 psid
33
Q

Auxiliary Spray Valves (CHA-HV-205 and CHB-HV-203):

  • F.O. or F.C.?
  • Power: ?
  • Do both valves have a remote switch at RSP?
  • A or B? Train valve has Remote/Local switch (App. R)?
A

Auxiliary Spray Valves (CHA-HV-205 and CHB-HV-203):

  • Fail closed
  • Power: PKB-D22 (HV-203) and PKA-D21 (HV-205)
  • Both valves have a remote switch at RSPs.
  • B Train valve has Remote/Local switch (App. R)
34
Q

Seal Injection Temperature Isolation Valve (CHE-UV-231P):

  • ?…

Seal Injection HX:

  • ?…

RCP Seal Injection Filters:

  • ?…

Seal Injection Containment Isolation Valve (HV-255):

  • ?…
A

Seal Injection Temperature Isolation Valve (CHE-UV-231P):

  • Full open or closed.
  • Fails OPEN
  • Auto closure: Hi-Hi (150°F) or Lo-Lo (70°F) Seal Injection Temp (3 second TD)
  • Does not fail on loss of power to TIC

Seal Injection HX:

  • Originally designed to heat seal injection.
  • Aux Steam piping to the HX has been blanked off.

RCP Seal Injection Filters:

  • Removes impurities to prevent seal damage.
  • Normally one in-service.

Seal Injection Containment Isolation Valve (HV-255):

  • PHB (MOV)
  • No auto features
35
Q

RCP Seal Injection FCVs (FV-241,242,243,244):

  • Controls flow to where?…
  • What type of acting controllers?
  • F.O. or F.C?…
  • Power Supplies?…
A

RCP Seal Injection FCVs (FV-241,242,243,244):

  • Controls flow to RCP seals.
  • Reverse acting controllers (100% - FCV closed)
  • Fails open:
    • Loss of Air (isolated or loss of NKN-D42)
    • Loss of Power to Controller
  • NNN-D11 (1A/1B), NNN-D12 (2A/2B)
36
Q

Seal Bleed-off CIVs (CHA-UV-506 and CHB-UV-505):

  • F.C. or F.O.?
  • Auto Close: ?… (ESFAS signal)
    • Override?
A

Seal Bleed-off CIVs (CHA-UV-506 and CHB-UV-505):

  • Fails closed AOVs:
    • Loss of Air
    • Loss of Power (PK)
  • Auto Close: CSAS
    • Override (white light)
37
Q

Seal Bleed-off Relief Valve Isolation Valve: (CHA-UV-507):

  • ?…

Seal Bleedoff Relief Valve (CHN-PSV-199):

  • ?…
A

Seal Bleed-off Relief Valve Isolation Valve: (CHA-UV-507):

  • Normally open
  • Fails open AOV: Loss of Air or power (PKA)
  • Places SBO relief to the RDT in-service

Seal Bleedoff Relief Valve (CHN-PSV-199):

  • Maintains bleed-off if the normal path is isolated.
  • Directs bleed-off to the RDT
  • Lifts at 225 psig.
38
Q

{…not highlighted in Welch’s Notes…}

Chemical Addition Tank / Pump:

  • ?…
A

{…not highlighted in Welch’s Notes…}

Chemical Addition Tank / Pump:

  • Allows chemicals to be added to the RCS.
  • Lithium added to ↑ pH induced by boric acid addition.

Hydrazine added for oxygen control when RCS is < 250°F.

39
Q

VCT:

  • gallon capacity (%/gal)?…
  • normal level?
  • normal press (min & max)
  • normal H2?

Alarms:

  • ?…
  • ?…
  • ?…
A

VCT:

  • 4900 gallon capacity (41 gal / %)
  • 34-44% normal level
  • 20-25 psig normal pressure
    • 3 psig - min pressure
    • 63 psig - max pressure
  • 25-50 cc/kg normal H2

Alarms:

  • VCT TRBL (VCT Temp Hi, VCT Lvl Hi-Lo, VCT Press Hi-Lo, CHN-UV-512 not in Auto, CHN-UV-500 not in Auto, CHN-UV-567 not in Auto, VCT LT Diff Hi, VCT Auto Makeup Demand.)
  • Lo-Lo VCT level (5%)
  • Hi-Hi VCT level (60%)
40
Q

LT reference legs:

  • LT-226 - ?
  • LT-227 - ?
  • common reference leg tap?
  • ?…
A

LT reference legs:

  • LT-226 - dry reference leg
  • LT-227 - wet reference leg
  • Common reference leg tap
  • Prevents leak on the tap from giving false high reading on both LTs. Prevents gas binding the charging pumps. (Diverting with no auto make-up)
  • VCT Level Differential Alarm at 6” (~ 8% level deviation/difference)
    • Indicates reference leg problems.
41
Q

LT-226:

  • ?…
A

LT-226:

  • MCR indication
  • 34% - Starts an auto makeup
  • 44% - Stops auto makeup
  • Low VCT Level alarms
  • Input to the VCT Level Differential Alarm at 6” (~ 8% level difference)
42
Q

LT-227:

  • ?…
  • 60% - ?
    • ?…
  • 5% - ?…
A

LT-227:

  • Plant Computer indication
  • RSP Indication
  • Local Indication
  • High VCT level alarm
  • 60% - diverts letdown flow (resets at 58%)
    • UV-500 to the Pre-HU Position
    • UV-565 to the Pre-HU IX Position
    • UV-567 to the HUT Position
  • 5% - swaps charging pump suction (resets at 15%)
    • Opens UV-514
    • Closes UV-501
    • Starts a BAMP
    • Closes UV-510
    • Opens HV-536 if UV-514 has lost power
43
Q

Normal VCT Makeup Supply Valve (CHN-UV-512):

  • ?…
A

Normal VCT Makeup Supply Valve (CHN-UV-512):

  • AOV
  • Auto Close:
    • BA or RMW Flow Deviation of ± 10 gpm (Makeup Mode Selector Switch in Auto).
    • 44% VCT level (auto make-up complete) [LT-226]
  • Auto Open:
    • 34% VCT level (Auto Makeup) [LT-226]
44
Q

Makeup to the Charging Pump Suction Valve (CHN-UV-527):

  • ?…
A

Makeup to the Charging Pump Suction Valve (CHN-UV-527):

  • AOV
  • Auto Open: Makeup Mode Selector Switch is taken to Manual, Borate, or Dilute (if in Open-Auto).
  • Auto Close: Makeup Mode Selector Switch is taken to Auto
  • Interlocked with 512. (If 512 is not closed, 527 will close / not open)
45
Q

Boric Acid Makeup to Charging Pump Suction (CHN-UV-514):

  • ?…
A

Boric Acid Makeup to Charging Pump Suction (CHN-UV-514):

  • MOV (NHN)
  • Auto Open: 5% VCT Lo-Lo Level [LT-227]
  • Auto Close: 15% VCT Lo-Lo Level clears [LT-227]
46
Q

RWT Gravity Feed to Charging Pump Suction Valve (CHE-HV-536):

  • MOV (PHA-M35 through NHN-M##?
  • Local controls at M##?
  • Auto opens: ?…
A

RWT Gravity Feed to Charging Pump Suction Valve (CHE-HV-536):

  • MOV (PHA-M35 through NHN-M72)
  • Local controls at M72
  • Auto Opens: VCT Lo-Lo Level (5% on LT-227) if CHN-UV-514 has no power.
47
Q

CVCS MAKEUP FLOW Alarm:

  • ?…
A

CVCS MAKEUP FLOW Alarm:

  • RMW or BAMP flow to the VCT > 3 gpm. Digital makeup will operate satisfactorily at flow rates < 2 gpm.
  • No alarm available if set to low flows. (reactivity control concern)
48
Q

Reactor Makeup Water Tank (RMWT):

  • ?…

Alarms:

  • ?…

RMW Flow Alarming Control:

  • ?…
A

Reactor Makeup Water Tank (RMWT):

  • Stores non-borated water for use in the RCS.
  • 480,000 gallon capacity.
  • Sufficient dilution to allow total recycle of the RCS.
  • Dilution for back-to-back shutdowns and subsequent startups at 90 % core life.
  • Alternate suction source for AFA/AFB pumps.
  • Inputs:
    • Boric acid condensate IX (distillate from BAC)
    • LRW System Recycle Monitor Tanks
    • DI water tank.

Alarms:

  • RMW TRBL (Lo Temp, LVL Hi-Lo, RMWP Disch Press Lo, RMW Filter DP Hi, RMW to VCT flow Hi (differential), RMW to VCT Refueling Shutdown flow Hi, RMW Pump overload, and CHN-UV-512 or 527 not reset)
  • Lo-Lo RMWT level

RMW Flow Alarming Control:

  • Alarm when makeup water flow (10 gpm) exist during refueling operations.
  • Alarm has to be manually enabled with HS on B03.
49
Q

{…not highlighted in Welch’s notes…}

Reactor Makeup Water Pumps (A/B):

    • ?…

RMWP Recirculation Valve (CH-511):

  • Small mini-flow line is provided for pump protection… Does valve failing close have an impact on the pump?
  • Auto open < # gpm?
  • Auto close > ## gpm?
A

{…not highlighted in Welch’s notes…}

Reactor Makeup Water Pumps (A/B):

  • NHN
  • Normally one running, one in STBY
  • Supplies CVCS make-up
  • Supplies Auxiliary Supply Header:
    • Charging pump seals
    • RDT
    • EDT
    • Boric acid eductor
    • Makeup supply header water for the batch tank
    • Resin transfer pump
    • Boric acid concentration for chemical addition tank
    • Gas stripper
    • Recycle drain header
    • Liquid Radwaste System Evap.

RMWP Recirculation Valve (CH-511):

  • Small mini-flow line is provided for pump protection therefore the valve failing closed has no immediate impact on the pumps.
  • Auto open < 10 gpm
  • Auto close > 20 gpm
50
Q

RMWP auto features:

Auto start (preferred, but is normally running):

  • ?…

Auto Stop:

  • ?…

Blue indication on what (…?)

A

RMWP auto features:

Auto start (preferred, but is normally running):

  • Makeup flow controller demand signal.
  • BAC running with no distillate pump running.

Auto Stop:

  • Makeup flow controller stop signal.
  • RMWT lo-lo level (1.5 sec TD).
  • Flow deviation from set-point, if pump was started on automatic demand.
  • Low discharge pressure. (10 sec – alarm, 24 sec TD – trip)
  • Loss of control power.
    • On loss of control power or overload, the other pump will start if in automatic.
  • Electrical protection.

Blue indication (low level, loss of control power, or low discharge pressure trip)

Will NOT auto start after low level or loss of control power trip

Interlock prevents both pumps from operating simultaneously.

An alternator swaps which pump starts on a makeup demand.

51
Q

Reactor Makeup Water Control Valve / Controller (210X):

  • ?…

Deviation from setpoint alarm:

  • ?…
A

Reactor Makeup Water Control Valve / Controller (210X):

  • Controls RMW flow to the VCT or Charging Pump Suction.
  • Fails closed: Loss of Air or power
  • Loss of power to controller:
    • Controller fails to Manual.
    • Valve, if open, will close.
    • FIC stays in Manual with NO output when power is restored.
    • Must be reset manually.
  • 210X auto closes when totalizer completes (auto/dilute/manual)
  • 210X = RMWT water*
  • 210Y =RWT water*

Deviation from setpoint alarm:

  • ± 5 gpm. 16 second TD.
  • During auto makeup closes UV-512 if flow deviation from setpoint is ± 10 gpm.
  • To reset you must take HS-512 to close then place it back in auto.
52
Q

Refueling Water Tank (RWT):

  • gallon capacity?
  • LCO? (volume)
  • # PPM boron?
  • temperature range?

Supplies:

  • ?…

Alarms:

  • ?…
  • % RWT lo-lo level alarm & stops BAMPS?
A

Refueling Water Tank (RWT):

  • 750,000 gallon capacity
  • LCO 3.5.5 volume
  • 4000-4400 ppm boron
  • 60-120°F

Supplies:

  • Boric acid makeup pumps
  • Charging pump alternate suction
  • Spent fuel pool
  • Safety Injection

Alarms:

  • BAM TRBL (BAMP Disch Press Lo, RWT Temp Lo, RWT Lvl Hi-Lo, BAM Filter DP Hi, BAM flow to VCT flow Hi (differential), BAMP overload)
  • 73% RWT Lo-Lo level alarm. Stops BAMPs.
53
Q

BAMP Suction Isolation Valve (CHN-UV-532):

  • Normally hand-jacked open… why?
A

BAMP Suction Isolation Valve (CHN-UV-532):

  • Normally hand-jacked OPEN with air isolated. Prevents inadvertently isolating Boration Flowpaths / Aux Spray (TRM SR).
54
Q

Boric Acid Makeup Pumps:

  • power supply
  • Supply:
    • ?…

Auto start:

  • ?…

Auto stop:

  • ?

Blue indication light on what?…

A

Boric Acid Makeup Pumps:

  • NHN
  • Supply:
    • Borated water to CVCS makeup.
    • Recirc RWT for cleanup.
    • Flow for the boric acid eductor.
    • Transfers RWT to the HUT.

Auto start:

  • Makeup flow controller demand signal
  • VCT Lo-Lo level (5%)

Auto stop:

  • Makeup flow controller stop signal.
  • RWT lo-lo level (73% for 1.5 sec TD)
  • Flow deviation from set-point (if auto started)
  • Low discharge pressure. (16 sec – alarm, 24 sec TD – trip)
  • Loss of control power
    • Loss of control power or overload will start the other pump if in automatic.
  • Electrical protection.

Blue indication (low level, loss of control power, or low discharge pressure trip)

Will NOT auto start after low level or loss of control power trip

Interlock prevents both pumps from operating simultaneously.

An alternator swaps which pump starts on a makeup demand.

55
Q

BAMP Recirc Valve (CHN-UV-510):

  • ?…
  • Auto closes:
    • ?…
  • Auto Opens:
    • ?…
A

BAMP Recirc Valve (CHN-UV-510):

  • Fails closed.
  • Allows recirc thru filter. Mini-flow lines also provided.
  • Auto closes:
    • > 20 gpm
    • 5% VCT lo-lo level
  • Auto Opens:
    • < 10 gpm
    • VCT level lo-lo reset (15%)
56
Q

Boric Acid Makeup Control Valve (210Y):

  • ?…

Deviation from setpoint alarm:

  • ?…
A

Boric Acid Makeup Control Valve (210Y):

  • Fails closed: Loss of Air or power
  • Flow is set < 40 gpm. If needed, raise > 40 gpm after flow established. Prevents hunting.
  • Loss of power to FIC will place it in manual with no output. Has to be manually reset.
  • Auto closes when totalizer completes (auto/dilute/manual)

Deviation from setpoint alarm:

  • ± 5 gpm. 16 second TD.
  • During auto makeup closes UV-512 if flow deviation from setpoint is ± 10 gpm.
  • To reset you must take HS-512 to close then place it back in auto.
57
Q

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Automatic: (Normally set to 100 gpm total):

  • 34% VCT level (226)…?
  • Pumps auto start.
  • 512 opens…
  • ?…
A

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Automatic: (Normally set to 100 gpm total):

  • 34% VCT level (226) – make-up starts
  • Pumps auto start.
  • 512 opens (makeup flow to VCT).
  • 210X and 210Y modulate open to preset values
  • > 20 gpm - recirculation valves will close.
  • 44% VCT level (226) – auto makeup stops; components go back to normal
58
Q

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Manual:

  • 527 opens…?
  • Pump must be manually started?…
A

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Manual:

  • 527 opens (flow to charging pump suction).
  • Pump must be manually started.
  • 210X and 210Y will modulate open to the preset values
  • > 20 gpm - recirculation valves will close.
  • When manual makeup is complete, pumps must be manually stopped. Valves automatically go back to normal.

Per the procedure, borate, dilute, or manual blend can be directed to VCT (instead of charging pump suction) by opening 512 prior to starting. Interlock will prevent 527 from opening.

59
Q

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Borate:

  • ?…
  • 527 opens…?
  • ?…
A

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Borate:

  • Batch amount manually set on the boric acid flow integrator.
  • BAMP auto start.
  • 527 opens (flow to charging pump suction)
  • 210Y modulates open to preset value.
  • > 20 gpm - recirculation valve (510) will close.
  • When batch amount is completed, 210Y will auto close with recirc (510) opening (< 10 gpm).
  • When Switch moved out of BORATE position, pump will automatically stop and 527 will close.

Per the procedure, borate, dilute, or manual blend can be directed to VCT (instead of charging pump suction) by opening 512 prior to starting. Interlock will prevent 527 from opening.

60
Q

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Dilute:

  • ?…
  • 527 opens…?
  • ?…
A

{…not highlighted in Welch’s Notes…}

Make-up Mode Selector Switch (HS-210):

Dilute:

  • Batch amount must be manually set on the Reactor Makeup Water flow integrator.
  • RMWP will auto start if not already running
  • 527 opens (flow to charging pump suction)
  • 210X modulates open to preset value.
  • > 20 gpm - recirculation valve (511) will close.
  • When batch amount is completed, 210X will automatically close with recirc (511) opening (< 10 gpm).
  • When switch is moved out of DILUTE position, pump will automatically stop and 527 will close.

Per the procedure, borate, dilute, or manual blend can be directed to VCT (instead of charging pump suction) by opening 512 prior to starting. Interlock will prevent 527 from opening.

61
Q

LCO 3.5.5 Refueling Water Tank (RWT) [Modes 1 – 4]:

  • ?…
  • ?…
A

LCO 3.5.5 Refueling Water Tank (RWT) [Modes 1 – 4]:

  • 8 hr LCO for boron and temperature OOS
  • 1 hr LCO or RICT for any other reason (level)
  • Level limits bases:
    • Volume transferred to CTMT prior to reaching a low level switchover. This ESF Reserve Volume ensures that the pump suction will not be aligned to the sump until the point at which 75% of the minimum design flow of one HPSI pump is capable of meeting or exceeding the decay heat boil-off rate.
    • Prevents vortexing and ensures adequate NPSH to support ESF pump operation on sump recirc.
    • Supports Containment Spray as credited in the CTMT pressure and temperature analyses.
    • Ensures SDM is maintained during a LOCA.
  • Minimum boron (4000 ppm):
    • Ensures that, following a LOCA with a minimum level in the RWT, the reactor will remain subcritical in cold conditions following mixing of the RWT and RCS water volumes. BOL is most limiting.
    • SB LOCAs assumes all rods are inserted, except CEA of highest worth.
    • LB LOCAs assume that all CEAs remain withdrawn. (core voiding adds the negative reactivity)
  • Maximum boron (4400 ppm):
    • Minimize boron precipitation in the core following a LOCA.
  • Temperature limits based on accident analysis assumptions.
62
Q

TLCO 3.1.100 Flow Paths – Shutdown [Mode 5 & 6]:

  • ?…

TLCO 3.1.102 Charging Pumps – Shutdown [Mode 5 & 6]:

  • ?…

TLCO 3.1.104 Borated Sources – Shutdown [Mode 5 & 6]:

  • ?…

Shutdown TRs not met: immediately stop…what activity?…

A

TLCO 3.1.100 Flow Paths – Shutdown [Mode 5 & 6]:

  • One flow path required.
    • From the SFP via a gravity feed connection and a charging pump to the RCS.
    • From the RWT via either a charging pump, a HPSI pump, or a LPSI pump to the RCS.
  • If none, immediately suspend core alts and positive reactivity additions.

TLCO 3.1.102 Charging Pumps – Shutdown [Mode 5 & 6]:

  • At least one charging pump or one HPSI pump or one LPSI pump in the boron injection flow path and capable of being powered from an operable emergency power source (normal or DG).

TLCO 3.1.104 Borated Sources – Shutdown [Mode 5 & 6]:

  • SFP or RWT shall be functional (≥ 33,500 gallons, 4000 – 4400 ppm)
    • RWT: 60 – 120°F
    • SFP: 60 – 180°F

Shutdown TRs not met: immediately stop core alts and positive reactivity changes.

63
Q

TLCO 3.1.101 Flow Paths – Operating [Mode 1-4]:

  • ?…

TLCO 3.1.103 Charging Pumps – Operating [Mode 1-4]:

  • ?…

TLCO 3.1.105 Borated Sources – Operating [Mode 1-4]:

  • ?…

Operating TRs not met: restore in ## hours…?

A

TLCO 3.1.101 Flow Paths – Operating [Mode 1-4]:

  • Two of the three flow paths required (Sources – charging pump – RCS)
    • Gravity feed from RWT or SFP thru CH-536 and a charging pump to the RCS
    • Gravity feed from RWT thru CH_-327_ (RWT Gravity Feed/SI System Isolation Valve) and a charging pump to the RCS
    • Gravity feed from RWT or SFP through CH-164 (BA Filter Bypass Valve) and a charging pump to the RCS.
  • Flow rate: ≥ 26 gpm for one pump and ≥ 68 gpm for two charging pumps (RCS at NOP)

TLCO 3.1.103 Charging Pumps – Operating [Mode 1-4]:

  • At least two charging pumps shall be functional.

TLCO 3.1.105 Borated Sources – Operating [Mode 1-4]:

  • SFP shall be functional (level based on Tcold) (RWT operability covered by LCO 3.5.5)

Operating TRs not met: restore in 72 hours.

64
Q

TRM Boration System Bases:

  • ?…
  • ?…
A

TRM Boration System Bases:

  • Control reactivity during power changes, maintain SDM, makeup for reduction in RCS volume due to contraction and nominal system losses, makeup for losses due to small breaks in the RCS, provide RCP seal injection, and control RCS pressure with auxiliary spray when required.
  • Two charging pumps ensures mitigation of a small break in the RCS. Consideration of a single failure is not required. Nominal net charging rate of 68 gpm from two charging pumps (i.e., 26 gpm + 42 gpm) exceeds the max break flow and will prevent violation of fuel design limits during the subsequent controlled cooldown.
  • Paths that use normal charging pump suction are not functional unless VCT outlet valve CH-501 can be closed.
  • Availability of an additional flow path from the charging pump discharge to the RCS is implied.
  • Actions outside the control room required for aligning the flowpaths.
65
Q

Reactor Drain Tank (RDT):

  • Receives water/steam from:
    • ?…
  • # – # psig N2 blanket?
  • # psig – high pressure alarm?
  • ## psig – RDT isolates [Outlet valve (560) and Vent Valve (540) close]?
  • #% - minimum quench volume / low level alarm / pump trip?
  • ## % - high level alarm?
  • ### psid - Rupture disc opens to CTMT?
  • ## °F – High temp alarm?
  • Vent to Gaseous Radwaste when < ## psig?.
  • Vent to CTMT through RDT Remote Manual Vent Valve (HV-923) when > ## psig?
  • Preferred method when pumping the RDT?…. (Gas stripper is normally bypassed)…
A

Reactor Drain Tank (RDT):

  • Receives water/steam from:
    • PZR safeties
    • SDC/SI relief valves
    • RCP Vapor Seal leak-off
    • Gravity drains / leakage of reactor grade quality water from components in CTMT
    • RCP Seal Bleed-off via 225 psig relief valve
    • PZR / Reactor Head Vents
  • 0.5 – 5 psig N2 blanket
  • 5 psig – high pressure alarm
  • 10 psig – RDT isolates [Outlet valve (560) and Vent Valve (540) close]
  • 52% - minimum quench volume / low level alarm / pump trip
  • 75% - high level alarm
  • 120 psid - Rupture disc opens to CTMT
  • 140°F – High temp alarm
  • Vent to Gaseous Radwaste when < 10 psig.
  • Vent to CTMT through RDT Remote Manual Vent Valve (HV-923) when > 10 psig.
  • Pumping RDT to the HUT, through the PHIX and Gas Stripper, is the preferred method when pumping the RDT. (Gas stripper is normally bypassed)
66
Q

CHA-UV-560 (RDT Outlet Isolation Valve):

  • ?…

CHB-UV-561 (RDT Outlet Isolation Valve):

  • ?…
A

CHA-UV-560 (RDT Outlet Isolation Valve):

  • AOV, Fails closed (loss of air / power)
  • Isolates:
    • CIAS (can be overridden)
    • 10 psig in RDT

CHB-UV-561 (RDT Outlet Isolation Valve):

  • AOV, Fails closed (loss of air / power)
  • Isolates: CIAS (can be overridden)
67
Q

CHN-UV-540 (RDT Vent Valve):

  • ?…

CHN-HV-923 (RDT Remote Manual Vent Valve):

  • ?…

CHA-UV-580 (RDT Makeup Supply Isolation Valve):

  • ?…
A

CHN-UV-540 (RDT Vent Valve):

  • AOV, Fails closed (loss of air / power)
  • Isolates: 10 psig in RDT

CHN-HV-923 (RDT Remote Manual Vent Valve):

  • SOV
  • Fails closed (loss of power)
  • Vents to CTMT, used if > 10 psig in RDT

CHA-UV-580 (RDT Makeup Supply Isolation Valve):

  • Fails closed (loss of air / power)
  • RMW must be manually aligned in the Aux Bldg.
68
Q

Equipment Drain Tank:

  • Receives water from:
    • ?…
  • # psig N2 blanket to exclude oxygen?
  • Vented to where?
  • # psig - auto isolates?
  • ##% - minimum quench volume / alarm / pump trip?
  • Relief valve (## psig). Relieves to non-ESF sump?
A

Equipment Drain Tank:

  • Receives water from:
    • Recycle drain header
    • Ion exchanger drain header
    • Gas stripper bypass for up to 30 minutes.
      • Gas stripper originally designed to process letdown flow to the HUT automatically.
      • EDT sized to accept 30 minutes of letdown flow if Gas Stripper was not able to accept flow.
    • Discharge from miscellaneous relief valves outside CTMT. (Letdown / ECCS / etc.)
  • 3 psig N2 blanket to exclude oxygen.
  • Vented to Aux Building HVAC Exhaust through CHN-PCV-568 to reduce EDT pressure.
  • 7 psig - auto isolates
  • 35% - minimum quench volume / alarm / pump trip
  • Relief valve (30 psig). Relieves to non-ESF sump.
69
Q

{…Not highlighted in Welch’s Notes…}

Equipment Drain Tank:

CHN-UV-562 (Misc Drains to EDT FCV):

  • ?…

CHN-UV-563 (Suction to RDT Pumps from EDT):

  • ?…

CHN-UV-564 (EDT to Gas Analyzer Isolation):

  • ?…
A

{…Not highlighted in Welch’s Notes…}

Equipment Drain Tank:

CHN-UV-562 (Misc Drains to EDT FCV):

  • Fails closed (loss of air / power)
  • Isolates: 7 psig in EDT

CHN-UV-563 (Suction to RDT Pumps from EDT):

  • Fails closed (loss of air / power)
  • Isolates: 7 psig in EDT

CHN-UV-564 (EDT to Gas Analyzer Isolation):

  • Fails closed (loss of air / power)
  • Isolates: 7 psig in EDT
70
Q

{…Not highlighted in Welch’s Notes…}

Reactor Drain Pumps:

  • ?…
  • Interlocks:
    • Only one RDP can be operated at a time?
    • Auto Stop (loss of suction protection):
      • ?…
A

{…Not highlighted in Welch’s Notes…}

Reactor Drain Pumps:

  • Transfers the contents of RDT or EDT to the HUT.
  • Flow path (using or bypassing Gas Stripper or PHIX) - based on chemistry and radiological condition of the water.
  • 165 gpm capacity
  • Interlocks:
    • Only one RDP can be operated at a time.
    • Auto Stop (loss of suction protection):
      • Low RDT level (if pumps aligned to RDT)
      • Low EDT level (if pumps aligned to EDT)
      • Loss of suction path (560 or 561 and 563 closed)
      • Diversion of letdown flow to PHIX (operation of UV-500)
      • Must be manually restarted once the initiating condition clears.
71
Q

Pre Holdup Ion Exchanger (PHIX):

  • Purifies: ?…
  • used whenever…?
  • When is PHIX bypassed?…

CHE-UV-565 (PHIX Temperature Bypass Valve):

  • Fail to the WHICH position?
  • Shifts to IX position on:
    • ?…
    • ?…

CHE-UV-566 (PHIX Outlet Valve):

  • ?…

CHN-UV-567 (Gas Stripper Outlet Valve):

  • Fails to WHICH position?…
  • Shifts to HUT position on:
    • ?…
    • ?…
A

Pre Holdup Ion Exchanger (PHIX):

  • Purifies: Reactor drain pump discharge, VCT diversion (Letdown flow), HUT Pumps
  • Used whenever flow is directed through the gas stripper to the HUT for storage.
  • If letdown flow is to be returned to the VCT, then the PHIX is bypassed.

CHE-UV-565 (PHIX Temperature Bypass Valve):

  • Fail to the BYPASS position
  • Bypass position on:
    • IX Hi Inlet Temp 140 °F
      • Manually reset ≤ 135 °F
  • Shifts to IX position on:
    • Hi-Hi VCT Level of 60% if no Hi Inlet Temperature present.
    • Returns to the Bypass position when Hi-Hi VCT Level Clears (58%)

CHE-UV-566 (PHIX Outlet Valve):

  • Fails to EDT position
  • Shifts to the EDT position on Gas Stripper Hi-Hi level if HS in AUTO.

CHN-UV-_567 (Gas Stripper Outlet Valve)_:

  • Fails to HUT position
  • Shifts to HUT position on:
    • Hi-Hi VCT Level (60%)
    • Returns to VCT position when Hi-Hi VCT Level Clears (58%)
72
Q

{…Not highlighted in Welch’s Notes…}

Gas Stripper operation:

  • ?…
A

{…Not highlighted in Welch’s Notes…}

Gas Stripper operation:

  • Degasses process fluid in the system.
  • Non-condensable gases and trace quantities of water vapor, are discharged to the waste gas surge tank.
  • Water passes through the heat recovery HX.
  • Small portion of the outlet flow from the stripper column is diverted to the reboiler where it is converted to steam and directed back to the stripper column.
  • Steam rises through the packing, condenses, and joins the spray flow.
  • Combination of high temperature, spraying and impingement into the packing and further heating in the packing causes gasses to rise above the spray line into the overhead condenser.
  • Gas temperature is reduced to < 140ºF, maintained at 3-7 psig by PCV (PV-706) and directed to the waste gas surge tank and gas analyzer.
  • The discharge pumps (CHN-P10A, B) send the degassed flow from the bottom of the stripper column through the heat recovery heat exchanger and the after cooler where it is cooled down to a ≤ 130ºF for return through LCV to the HUT of VCT.
  • During shutdown conditions, the gas stripper is maintained with a low pressure N2 blanket.
73
Q

{…Not highlighted in Welch’s Notes…}

Boric Acid Reclamation:

  • ?…
A

{…Not highlighted in Welch’s Notes…}

Boric Acid Reclamation:

  • Store and process relatively clean borated water for re-use and/or for volume reduction.
  • Water is stored in the HUT and processed by the BAC.
  • Borated “concentrates” are re-used or stored for further processing for disposal, and the water that is boiled off may be condensed into liquid for re-use or released as vapor for volume reduction.
  • Designed to operate with boric acid concentrations below the point where precipitation could occur.
  • Boric acid batching tank and RWT concentrator (BAC) concentrate discharge line to the solid radwaste system are the only portions of the system requiring heat tracing to preclude boric acid precipitation. Can contain fluid concentrated to 12 weight percent boric acid.
  • Remaining portions of the system contain a lower boric acid (< 4400 ppm).
74
Q

Boric Acid Concentrator Flow Paths:

  • EDT, RDT, and RCS Letdown Diversion are directed to where?….
  • Then pumped directly to the BAC and concentrated to desired boron concentration by evaporation…?…
  • Auxiliary steam (AS) system provides what to BAC?…
  • Distillate is condensed using which cooling water system? at the BAC Condenser?…
  • ?…
  • A BAC steam vapor release to the plant vent requires what type of Permit?… (Steam vapor contains tritium as part of the water molecule)
A

Boric Acid Concentrator Flow Paths:

  • EDT, RDT, and RCS Letdown Diversion are directed to the HUT for storage.
  • Then pumped directly to the BAC and concentrated to desired boron concentration by evaporation (boiling).
    • Concentrates are normally sent to the RWT for reuse in the plant.
    • Concentrates could also be sent to the LRW Concentrate Monitor Tanks for disposal.
  • Auxiliary steam (AS) system provides steam to the BAC.
  • Distillate is condensed using NCW at the BAC Condenser.
  • Portion of this distillate is used for pump seals and Flash Tank level instrumentation
  • Remaining liquid distillate is recirced back to the BAC skid or sent to Boric Acid Condensate IX and then to RMWT for reuse.
    • Distillate (steam) can also be sent to the Plant Vent.
  • The original intent of this was to reduce RCS Tritium concentration. It is important to realize that the ability to release distillate as steam makes the BAC essential to the continued operation of the plant because “new” water (that didn’t originate from the primary or primary connected systems) enters Radwaste. This is due to limited Radwaste/Plant primary side water storage capacity and no reasonable alternate method of reducing excess Radwaste/Plant primary side water inventory.
  • A BAC steam vapor release to the plant vent requires a Radioactive Effluents Discharge Permit. (Steam vapor contains tritium as part of the water molecule)
75
Q

Holdup Tank (HUT):

  • Stores what?
  • Capacity?
  • temperature? maintained how?
  • level in ft. to start processing?
  • Normally vented to where?

Holdup Tank (HUT) Pumps:

  • Transfer HUT to where?…
  • Controlled how/where?…
  • Can we operate two pumps at same time (interlocked)?
  • Trips:
    • ?…
    • ?…
    • ?…
    • ?…
A

Holdup Tank (HUT):

  • Stores all recoverable reactor coolant and provides NPSH for holdup pumps.
  • 550,000 gallon capacity
    • Designed to store all recoverable water from back-to-back cold shutdowns to 5% subcritical and subsequent startup at 90% core life.
  • Maintained > 60ºF by two sets heaters.
  • ~ 17 ft - BAC is used to start processing
  • Normally vented to FB vent system.

Holdup Tank (HUT) Pumps:

  • Transfer HUT to the BAC
  • Locally controlled at the HUT
  • Cannot operate two pumps at same time (interlocked)
  • Trips:
    • Lo-Lo Level in HUT (28”)
    • Hi-Hi BAC flash tank level
    • Diversion of letdown flow (CH-500 to the PHIX) when the HUT contents are being re-purified (CH-V686 open).
    • Second pump is started.

.AR LOIT Systems: Welch's Highlighted Notes (60 decks)

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