Ice Condenser(NF) Flashcards
What is the purpose of the Ice Condenser Refrigeration System?
- The ice condenser provides a large heat sink to rapidly reduce containment pressure and temperature during:
A. Loss of coolant accident
B. Steam line break - Steam from either casualty is directed through the ice condenser to accomplish:
A. Continues to lower pressure after an accident less than or equal to 15psig
B. Controls iodine by controlling pH in the containment sump by maintaining pH slightly basic
C. Controls chloride and caustic stress corrosion by adjusting pH
D. Provides neutron absorption by maintaining boron in the containment sump from the ice
What is the system designator for the Ice Condenser Refrigeration System?
NF
What is the design/purpose of the Ice Condenser Baskets?
- 12 inches in diameter and approximately 48 feet high
2. Maintain the geometry of the ice and promote heat transfer
What is the design/purpose of the Ice Condenser Floor Cooling System?
- Insulated concrete wear slab with embedded cooling coils
- Two floor cooling pumps circulate glycol through each bay’s set of cooling coils
- Glycol is supplied from the Air Handling Unit Supply Header
What is the design/purpose of the Ice Condenser Drain Valves?
The Ice Condenser Drain Valves allow drainage during an accident directly to the lower containment. Normal drainage is not enough to open the valve. A small drainage line, connected to the 12 inch line, handles normal drainage and is directed to the Containment Floor and Equipment Sump.
What is the design/purpose of the Lower Inlet Doors?
- Normally held shut by the head of the cold air in the Ice Condenser, if removed they will be partially open
- Designed to fully open at 1 lb/ft2 differential pressure
What is the design/purpose of the Intermediate Doors?
- Provide a vapor barrier between the high humidity air in the ice bed and the low humidity air in the upper plenum
- Limits the loss of ice due to sublimation
- Provides a walking surface on top of the ice baskets
What is the purpose of the Turning Vanes?
The Turning Vanes direct steam flow up through the ice baskets
What is the purpose of the Impingement Plates?
The impingement plates on the containment wall prevent erosion of the containment wall from high energy incoming steam
What indications does the Ice Condenser Zone Monitor Panel provide and where is it located?
- Each light on the panel provides indication for four inlet door assemblies(8 doors). They show open and closed indication.
- The panel is located outside of the Ice Condenser Lower Access Door.
What is the design/purpose of the Ice Bed Temperature Monitoring?
- There are 47 RTDS total
- 1-45 are in the ice bed
- RTDs 46 and 47 are located in the Upper Plenum
- Point 48 on the chart recorder is an average of the 47 points
- There is a common annunciator in the Control Room for low and high alarms
How many Air Handling Units are there, and what is the air flow path?
- There are 30 Air Handling Units
- The air flow path is from around the AHU in the upper ice condenser down through the Wall Panels next to the ice beds, and then back up through the Wall Panels to be repeated.
- The AHUs have a backdraft damper to prevent backflow through a non operating AHU
How many Chiller Packages and Glycol Pumps are there in the Ice Condenser Refrigeration System?
- There are 6 Glycol Pumps
- There are 10 Chiller Packages
- There are normally 3 to 4 Chiller Packages in service per unit
What system provides the cooling water to the Chillers?
Recirculated Cooling Water(KR)
How many Glycol Pumps and Chiller Packages are normally in service?
We run one less Glycol Pump than the Chiller Packages that are in service.
