USCG Exam PracticeBoiler and steam propulsion fundamentals
In a marine water-tube boiler, what is the primary purpose of the economizer?
- A. To superheat steam above its saturation temperature before it enters the turbine
- ✓ To preheat incoming feedwater using heat recovered from the flue gasCorrect
- C. To remove dissolved oxygen and carbon dioxide from the feedwater
- D. To control the concentration of dissolved solids by skimming surface water
Why B is correct
The economizer is a heat-recovery surface positioned in the flue gas path that preheats incoming feedwater before it enters the drum. The superheater raises steam temperature above saturation; the deaerating feed tank removes dissolved gases; and surface blowdown controls dissolved solids. (NAVEDTRA 14104 §4-1)
Cited:NAVEDTRA 14104 §4-1