What is the driving force for feedwater to reach the Deaerating Feed Tank (DFT)?

What is the driving force for feedwater to reach the Deaerating Feed Tank (DFT)?

• A. Suction from main or auxiliary condenser
• B. Pump discharge pressure
• C. Gravity feed from storage tank
• D. Boiler pressure

Answer: (A)

The driving force is the suction created by condensate pumps pulling condensate from the condenser hotwell into the Deaerating Feed Tank. Condensate from the main and auxiliary condensers returns to the hotwell, and the pump’s suction lowers the pressure at the DFT inlet, drawing the condensate into the DFT where it is deaerated and stored for boiler feed. Gravity from a storage tank wouldn’t reliably move the condensate, boiler pressure would tend to push water back or oppose the flow, and using pump discharge pressure wouldn’t pull water into the DFT. The condensate pump suction on the condenser side provides the continuous driving force.

The driving force is the suction created by condensate pumps pulling condensate from the condenser hotwell into the Deaerating Feed Tank. Condensate from the main and auxiliary condensers returns to the hotwell, and the pump’s suction lowers the pressure at the DFT inlet, drawing the condensate into the DFT where it is deaerated and stored for boiler feed. Gravity from a storage tank wouldn’t reliably move the condensate, boiler pressure would tend to push water back or oppose the flow, and using pump discharge pressure wouldn’t pull water into the DFT. The condensate pump suction on the condenser side provides the continuous driving force.