Condensate Flashcards
Where does main condenser collects from ?
-Main Turbine Exhaust Steam
-MFWP Exhaust Steam
-Extraction Steam Drains from LPFW Heaters
-Other equipment
How is each condenser section divided into two halves ?
1A,2A
1A,2B
1C,2C
What helps maintain vacuum in the condenser shells ?
Established & maintained by both Condenser Air Removal & condensing action of exhaust steam
What is the vacuum in each condenser shell?
A shell: 1.5 - 2.5HgA
B shell: 2.0 - 2.5HgA
C Shell: 2.8 - 4.3HgA
Why do the tube bundles in each condenser shell get longer ?
Longer in each shell because circulating water gets warmer as it goes through each shell
Where are the AR system installed for each tube bundle ?
AR system installed in middle of each tube bundle
Why is AR system installed in middle of each tube bundle ?
-Minimize condenser pressure & maximize turbine efficiency
-Minimize oxygen concentration in condensate to prevent oxygen from reaching Steam Generator
What’re the Main Condenser Expansion Joints used for ?
-Connects each condenser shell to LP Turbine
-Prevents air leakage into condenser while allowing movement between Turbine Casing & Condenser Sections
Each Main Condenser Expansion Joint has a trough around seal, why would we fill it with water ?
Normally kept dry, but could be filled water if joint seal has hole water will be drawn into condenser instead of air
What water is used to fill the Expansion Joint Seal trough ?
Filled with Condensate Service Header if there’s a hole in joint seal
If water is introduced to trough, why is important to keep it maintained ?
If trough is drained out than it could cause neoprene seal to crack
How is water level maintained in the Expansion Joint Seal trough ?
Maintained by locking makeup valve in throttled position to provide trickle of water to trough
What’re the Main Condenser Equalization Ducts used for?
Protects condenser from damage due to high DP
Where does the condenser equalizing receive its seal water from?
Seal water provided from Condensate Service Header
How do the Condenser Equalizing Ducts work ?
-Allows pressure equalization if pressure DP rises between shell
-Water seal will blow out if temperature difference is 30F
How can you indicate level inside the Condenser Equalizing Ducts ?
There is a local sight glass to monitor level
What’re the Main Condenser Vacuum Breakers used for ?
Installed each condenser section,allows rapid Main Turbine slowing down under normal & emergency conditions
Why is the Vacuum Break Line filled with water? What water is used ?
-Filled with water from Condensate Service Header
-Water ensures any leakage past valve will draw water instead of air into condenser
What does the Vacuum Break Line have on the atmosphere side to prevent debris from entering line ?
There is a conical screen to prevent debris from entering
What does the inner bottom sump do ?
They collect condensate from each half of the condenser shell which is done by a divider plate
What does the divider plate that separates each shell half allow us to do during condenser tube rupture ?
It’ll allow us to isolate main condenser half upon a tube leak
What does the water in the inner bottom sump provide ?
Forms water seal between LP in shell & HP in hotwell
What do the perforated plates at the bottom of inner bottom dumps do ?
Breaks up water & fall more slowly through reheat section
Where does the MFWPT direct it’s exhaust to ?
Exhaust directed to A reheat trays, then through hotwell equalization ducts to B reheat trays , then exhaust goes into C condenser and condenses since there no reheat trays
Which condenser shell pressure are the three hot wells at ?
Since there is no inner bottom sump in ‘C’ Condenser shell, then all hotwells are at ‘C’ Main Condenser
How do we indicate reheat tray level ?
Reheat Tray level sight glass is installed on A & B Condenser halves
How do we collect condensate samples from hotwell?
Allows chemically contaminated condensate to be detected when it enters hotwell
What does the salinity detection cabinet provide for the condenser chemistry ?
Provided required detention time to close circ water valves, & isolate hotwell halves to prevent chemically contaminated water from reaching steam generators
What does condensate sparging do ?
Hotwells can use Aux. Steam directly into Hotwell Reheat Section to preheat condensate secondary plant startup
What power level do we have to reduce to when there is a Main Condenser tube rupture ?
40% power level
How many gallons is maintained in the Main Condenser Hotwells ?
100,000 gallons of condensate storage & volume
What will automatically close the both hotwell makeup valves ?
Both valves are interlocked to close on a CST LO-LO LVL