DS/DW- Domestic/Demineralized Water Flashcards
What is the purpose of the DW system?
Provides continuous and sufficient supply of demineralized and degasified water to several systems and services
What is the purpose of the DS system?
Supplies potable water within the Power Block for human consumption, eye wash stations, and for other general uses
DW supplies makeup water to which Surge tanks?
Diesel Generator, Essential chilled water, Essential Cooling water, Turbine Cooling Water, Nuclear Cooling water, normal chilled water
What other tanks does DW provide makeup water to?
RMWT, CST, Stator Cooling Coolant Tank
How can DW support CD during a startup?
Can supply water to the Condensate Service Header
Which systems receive seal water from DW? What from DS?
Control building OW sumps and RD
DG sump pumps
How does DS system support ED system?
ED system receives blowdown stack quench water from the DS system
How does DS system support FP system?
FP system receives makeup water from DS
Why is a nitrogen cover gas maintained in the DWST?
To ensure the water remains free of oxygen during storage
What would trip the Demineralized Water Transfer Pumps? What happens when the level is restored?
Low-low level switch provided on the tank, electrical overload
pump auto restarts
What is the status of the Demineralized Water Transfer Pumps under normal operations? What pressure starts the standby DW transfer pump?
One pump (100% capacity) is continuously operating to pressurize the demineralized water supply header with the second pump operated as required by demand as sensed by a low discharge header pressure
96 psig, alarm at 91psig
Where is the control switch for the Demineralized Water Transfer Pumps? Where are the pumps located?
Control Room
south side of the DWST, north yard
How could we get DW if the Transfer Pumps or the Demineralized Water Storage tanks are unavailable?
Can be supplied directly from the Water Reclamation Demineralized Water header via a tank bypass and a valve
What is the purpose of the backflow preventer assembly and what does it consist of?
Designed to prevent any backflow per the Uniform Plumbing Code
Each BPA contains two spring-closed check valves, with a third spring-loaded check valve, which opens to the atmosphere upon a loss of line pressure
Any backflow is vented to atmosphere
Where are the pressure control valves and BPAs located?
North side of 74’ Control Building