Aux Steam Flashcards
What are the secondary uses for aux steam?
MSRs for blanketing steam when the main turbine is offline.
Gland sealing steam to the main turbine and FW pumps during startup.
What is the purpose of the aux steam system?
Provides low pressure steam to:
Gas stripper for degassification of the RCS.
Liquid radwaste system evaporator for water reclamation.
Boric acid concentrator for boron reclamation
Where can a given unit receive aux steam from?
Aux steam may come from the aux steam system of any other unit.
What cooling water is on the tube side of the vent condenser heat exchanger?
Nuclear cooling water.
Where is the condensate water directed if the aux steam discharge has high levels of radiation by RU7?
The liquid radwaste system low TDS holdup tank.
Where do the condensate transfer pumps receive power from?
NH
What systems are impacted with the loss of NH in relation to the aux steam system?
Aux steam in the aux building must be secured until power is restored.
Gas stripper, LRS evaporator and BAC no longer available.
What is the makeup water source for the Aux Steam system?
Demineralized water (DW)
Where is aux steam delivered after it is utilized?
The main condenser.
What is aux steam used for in the feed water pump turbine system?
Provides steam for overspeed testing of the feed water pump turbines.
What is the purpose of the condensate receiver tank in the aux steam system?
Collection point for condensate returning from the aux steam system. It provides NPSH required for condensate receiver transfer pumps.
If the rad monitor RU-7 detects high levels of radiation (closing ASN-RV-11A and opening ASN-RV-11B) what happens with the valves once the high level condition clears?
Nothing occurs automatically. The 11A valve must be manually reset by lifting the latch lever upward until it engages with the latch.
What happens to ASN-RV-11A and ASN-RV-11B upon loss of instrument air?
11A fails closed (main condenser system return)
11B fails open (rad waste low TDS holdup tank)
What happens to valves PV-331, 332 in the aux steam system when 1 of 20 pressure switches detects a 1.0 psig variance?
The valves will fail closed.
Pneumatically operated and must be manually reset once the cause of the over pressurization has been corrected.
What happens when the condensate transfer pump control switch is placed in auto?
Pump is controlled via level switches and will start automatically on high level in the receiver tank.
The standby pump starts on a hi hi tank level.
Both pumps stop on a low level in the receiver tank.
