Question 1198Deck General70% to pass
LNG boil-off is used as fuel in the dual fuel system to produce steam in the boilers to run the turbines. What happens under slow maneuvering speeds, due to excessive steam being generated?
AI Explanation
The correct answer is C) the steam produced in the boiler, due to the dual fuel system, is dumped to the main condenser.
This is the correct answer because under slow maneuvering speeds, the LNG boil-off generated in the dual fuel system would result in excessive steam production in the boilers. To prevent a dangerous buildup of pressure in the boiler, the excess steam is directed to the main condenser, where it can be condensed and recirculated back into the system.
The other options are incorrect because: A) venting the boil-off to the atmosphere would be wasteful and potentially hazardous; B) the boil-off is specifically permitted to be used as fuel in the dual fuel system; and D) venting the steam to the atmosphere would not be a safe or efficient way to handle the excess steam under slow maneuvering conditions.
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