Normal temperature of Deaerating Feed Tank (DFT)

Normal temperature of Deaerating Feed Tank (DFT)

• A. 250°F
• B. 200°F
• C. 300°F
• D. 150°F

Answer: (A)

Deaeration works by heating the feedwater so dissolved gases, mainly oxygen and carbon dioxide, are released and vented away. The Deaerating Feed Tank is kept hot but not boiling, typically around 250°F, which balances effective gas release with avoiding steam formation inside the tank. At this temperature (given the tank’s operating pressure), the water is near its saturation point enough to drive off gases, yet pressure prevents flashing into steam and carryover. If the water were cooler, less gas would come out of solution; if it were much hotter, you’d risk boiling and possible carryover, reducing deaeration efficiency. So 250°F is the normal operating temperature for proper deaeration and corrosion control.

Deaeration works by heating the feedwater so dissolved gases, mainly oxygen and carbon dioxide, are released and vented away. The Deaerating Feed Tank is kept hot but not boiling, typically around 250°F, which balances effective gas release with avoiding steam formation inside the tank. At this temperature (given the tank’s operating pressure), the water is near its saturation point enough to drive off gases, yet pressure prevents flashing into steam and carryover. If the water were cooler, less gas would come out of solution; if it were much hotter, you’d risk boiling and possible carryover, reducing deaeration efficiency. So 250°F is the normal operating temperature for proper deaeration and corrosion control.