Question 949Deck General70% to pass
During the ballast voyage, how are the tanks kept cold on an LNG tanker?
AI Explanation
The correct answer is D) spraying LNG heel through spray nozzles in the tanks.
During a ballast voyage, the LNG tanks on a tanker need to be kept cold to maintain the liquefaction of the natural gas. This is achieved by spraying a small amount of the remaining LNG (called the "heel") through nozzles installed in the tanks. The LNG heel acts as a coolant, helping to maintain the cryogenic temperatures required to keep the LNG in a liquid state. The other options, such as aggressive gas compression or venting gas, would not effectively maintain the tank temperatures during the ballast voyage.
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