Boil-off gas reliquefaction system with dual cooling sources

A reliquefaction method comprising:

• extracting a Boil-Off Gas (BOG) from a Liquefied Natural Gas (LNG) tank;
• determining a gas consumer load requirement;
• in response to the gas consumer load requirement exceeding a minimum threshold, separating the BOG according to the gas consumer load requirement into a first BOG stream that flows to a heat exchanger to be used as a first cooling source and a second BOG stream that flows directly to a compressor;
• mixing the first BOG stream and the second BOG stream to form a mixture of the first BOG stream and the second BOG stream that is compressed by the compressor;
• separating the compressed mixture into a third BOG stream to be delivered to a gas consumer and a fourth BOG stream to be delivered to the heat exchanger for reliquefaction;
• and
• reliquefying the fourth BOG stream using the first cooling source and a second cooling source provided by a refrigeration loop.

A reliquefaction method comprising:

• extracting BOG from a LNG tank;
• determining that a gas consumer load requirement is at or below a gas consumer load requirement minimum threshold;
• sending the BOG to a heat exchanger to be used as a first cooling source, which flows to a compressor downstream of the heat exchanger that compresses the gas exiting the heat exchanger;
• separating the compressed gas into a consumer stream to be delivered to a gas consumer and a reliquefaction stream to be delivered to the heat exchanger for reliquefaction;
• and reliquefying the reliquefaction stream using the first cooling source and a second cooling source provided by a refrigeration loop.