Ammonia fuel supply system and cold energy utilization system thereof

The utility model provides a marine ammonia fuel supply system and a cold energy utilization system thereof, the cold energy utilization system conveys ammonia fuel to an ammonia fuel cold energy absorption heat exchanger, and the ammonia fuel is utilized to provide cold energy for the ammonia fuel cold energy absorption heat exchanger; a refrigerating medium on the ship is directly conveyed to the ammonia fuel cold energy absorption heat exchanger to absorb cold energy, or a cold energy recovery medium absorbs the cold energy and then exchanges heat with the refrigerating medium on the ship, so that cyclic utilization of the cold energy of the ammonia fuel is realized. The low-temperature cold energy, about-30 DEG C, of the ammonia fuel is transmitted to the refrigerating system on the ship for cooling on the ship in a heat exchange manner, so that the cold energy of the ammonia fuel is utilized; the energy consumption of other refrigerating systems or ice-making systems on the ship can be saved, the heat en