Tankerman · Gas Carrier — Boil-Off Gas
On a liquefied gas carrier, cargo boil-off gas (BOG) results from:
- AAdding oxygen to the cargo
- BHeat leaking into the refrigerated/pressurized cargo, vaporizing some liquid that must be managed (reliquefied or burned)✓ Correct
- CLoading too slowly
- DCooling the cargo below absolute zero
Explanation
Despite insulation, ambient heat reaches the cold cargo and vaporizes a fraction (boil-off). BOG is handled by reliquefaction plant, by burning it as fuel (e.g., in boilers or dual-fuel engines), or by controlled venting only in emergencies — never simply released, given the flammability.
Authority: IGC Code; gas carrier operations
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