Method and system for reducing heating value of natural gas

A Ship comprising:

• a natural gas tank containing liquefied natural gas (LNG);
• a vaporizer connected to the tank and configured to gasify LNG from the tank to produce vaporized natural gas;
• a first heat exchanger connected to the vaporizer and configured to receive and heat exchange at least part of the vaporized natural gas, thereby liquefying a portion thereof, wherein the first heat exchanger employs cold heat generated upon regasification of the LNG to liquefy the portion of the vaporized natural gas;
• a gas-liquid separator connected to the first heat exchanger and configured to separate a liquefied portion from the heat exchanged natural gas;
• a second heat exchanger connected to the gas-liquid separator and configured to receive and heat exchange at least part of the remainder of the heat exchanged natural gas after the gas-liquid separator separates the liquefied portion from the heat exchanged natural gas, wherein the second heat exchanger employs cold heat generated upon regasification of the LNG to liquefy the remainder;
• a first output of the gas-liquid separator configured to supply all the liquefied portion to at least one combustion device of the ship such that all of the liquefied portion is consumed in the ship;
• a second output of the gas-liquid separator configured to supply at least part of the remainder of the heat exchanged natural gas to a nitrogen adding mechanism;
• and the nitrogen adding mechanism configured to receive the at least part of the remainder and add nitrogen thereto.