Boric Acid Reclamation Flashcards
What interlock is associated with the holdup pumps?
Interlocked so that they both cannot be operated at the same time.
They are stopped on low hut level, high BAC level, and diversion of letdown flow to the PHIX when contents are being purified (CH-V686 open)
What does the hold up tank do and where is it located?
Stores all recoverable RCS coolant and provides NPSH for the holdup pumps. Located in the RCA yard next to RMWT.
What boric acid concentration is achieved by the BAC?
4000-4400 ppm, the range that is required by the RWT
What is the concern with releasing the distillate vapor from the BAC to atmosphere?
The steam vapor contains tritium as part of the water molecules.
What is the distillate cooled from the BAC used for?
Pump seals and flash tank level instrumentation. The rest is recirced back to the BAC skid.
Where can the concentrates from the BAC be sent to?
HUT for holding until concentration is high enough for the RWT or the liquid Radwaste concentrate monitor tanks for disposal.
Why is there a hole in the BAC pump discharge check valve disc?
To allow some back flow and prevent boric acid solidification
What can running only 1 BAC pump cause?
Heater fouling
What temperature is the outlet of the concentrate cooler maintained at and why?
175F to prevent the Boron solidification in RWT piping when the concentrate outlet valve opens.
How are the demister pads in the vapor separator cleaned?
Spray nozzles using some distillate
Where does the vapor go when it leaves the vapor separator?
Out the plant vent at a maximum flow rate of 9000lbm/hr
Why and when is nitrogen used in the vapor condenser?
During shutdown to keep from pulling excessive vacuum during cool down and inhibit corrosion.
What starts the distillate pumps?
Sufficient level in the condenser. 76% is the high level alarm in the condenser.
Where can the concentrate monitor pumps move water to?
CVCS HUT
LRS concentrate monitor system
RWT
