Condensate System

Question 1

Purpose of the Condensate System

Answer 1

• Supplies water to the MFP suction from the Hotwell
• Can flow through the Polishers
• Provides flow through the LP feedwater heaters and SGBD HXs and Gland Steam Condenser to help heat the condensate and improve plant efficiency.

Question 2

Condensate Pumps

power supplies? Purpose?

Answer 2

• A is 4KV 1
• B is 4KV 4
• Take suction on the condensed LP Turbine Exhaust in the Hotwell, raise the pressure of the fluid and transport the higher pressure water to the suction of the feed pumps

Question 3

Condensate Pump

Loads? Seal water? Starts and Trips

Answer 3

• One pump can support 55-60% load
• Seal water provided from pump discharge or CST.
• Auto start of the standby condensate pump is provided if the other pump trips due to an electrical overload or if there is low discharge pressure.
• Trips include electrical breaker overload, under voltage, or the RTGB switch to STOP.

Question 4

Seal Water Booster Pumps

Purpose? Power supplies? Set points?

Answer 4

• Supplies seal water to the MFP HDPs at low loads and when condensate Pump pressure is no sufficient.
• DP < 30 psi for 30 secs, Lead pump starts
• DP < 30 psi for 40 secs, Lag pump starts
• DP > 100psi, pumps stop
• A MCC-3 B MCC-4

Question 5

MOV V5-3

Location, Power supply, how it works

Answer 5

• South Railing on 2nd level turbine Building
• Powered from MCC-8
• Valve will open 5% from RTGB until the entire Condensate system is pressurized to 300psig, then it will fully open once the switch is moved to open again.

Question 6

HCV-1459
LP Heater Bypass Valve
Purpose? Also causes what?

Answer 6

• IF a loss of Htr. Drn Pump (lose of 30% of MFW suction), this valve opens allowing some condensate flow to bypass the FW Heaters and flow directly to the suction of the MFPs. to increase pump suction pressure.
• If it opens, QVC-10436 CP secondary bypass valve also opens
• 300psi or lower suction on MFP with at least 1 HtD pump. 350psi and lower with no HtD pump

Question 7

RO-1414
What does it do?
What power level is associated with it and what happens?

Answer 7

• Ensures sufficient backpressure to cause adequate flow to the Gland Steam Condenser and SGBD Heat exchangers.
• 30% bypass valve closes to force water through the oriface

Question 8

Quench valves to HDT

Purpose? When do they actuate? how long? Located?

Answer 8

• ES-10 is a Non-return valve on FWH 5A/B that when it closes (steam flashing) the quench valves open to reduce temperature in the HDT to prevent cavitation of the HD Pumps
• They open for 6 minutes.
• 1 is located above the SDAFW
• Other is in the ceiling of the Hot Tool Room

Question 9

Exhaust Hood Spray

Does what? Set points? Protects?

Answer 9

• Opens when exhaust hood steam temp reaches high setpoint, to spray condensate to reduce temp.
• Starts to open at 160F (normally 140F)
• Fully open at 175F
• Protects LP turbine blades from over heating