Disclosed are a system and method for reliquefaction of boil-off gas of a ship and a system and method for treating off-gas of a reliquefaction apparatus. The boil-off gas reliquefaction system includes: a compressor compressing boil-off gas generated from liquefied gas stored in an on-board storage tank; a heat exchanger cooling the boil-off gas compressed in the compressor; a refrigerant circulation line in which a refrigerant supplied to the heat exchanger circulates; a temperature raising line extending from the storage tank to the compressor; and a heater provided to the temperature raising line, wherein the heater heats the boil-off gas to a suitable input temperature of the compressor.

A vessel including a hull, an upper deck, an accommodation structure extending above the upper deck, a propulsion system powered by ammonia as a fuel, and a tank for storing ammonia for supplying the propulsion system, wherein the tank is located aft of the accommodation structure.

A vessel including a hull, an upper deck, an accommodation structure extending above the upper deck, a propulsion system powered by ammonia as a fuel, and a tank for storing ammonia for supplying the propulsion system, wherein the tank is located aft of the accommodation structure.

A heat exchange system for use on an engine-powered watercraft includes a liquid cooling system for cooling the engine using a first heat exchanger and a water heating system using a second heat exchanger for heating water. Raw water from an external water source is passed through each heat exchanger. Water used to cool the engine coolant inside the first heat exchanger exits the watercraft. Water heated by the second heat exchanger is passed to either an intake conduit or at least one onboard accessory system for flushing thereof to kill aquatic invasive species. A valve inside the second heat exchanger opens to release heated water when the heated water reaches a temperature of at least 140 F. Heated coolant from the first heat exchanger passes through the second heat exchanger to transfer heat to the water inside the second heat exchanger.

A method for operating a cooling system of a ship, having a sea water part system with a sea water pump (14a, 14b) and at least one first cooling water circuit. The first cooling water circuit includes a bypass in a heat exchanger coupling the sea water part system and the first cooling water circuit and a control valve. A position of the control valve determines a cooling water proportion of the first cooling water circuit that is conducted via the heat exchanger and a cooling water proportion of the first cooling water circuit that is conducted via the bypass. The position of the control valve is controlled such that an advance cooling water temperature corresponds to a set point value. The rotational speed of the sea water pump is controlled based on the position of the control valve.

A method for operating a cooling system of a ship, having a sea water part system with a sea water pump (14a, 14b) and at least one first cooling water circuit. The first cooling water circuit includes a bypass in a heat exchanger coupling the sea water part system and the first cooling water circuit and a control valve. A position of the control valve determines a cooling water proportion of the first cooling water circuit that is conducted via the heat exchanger and a cooling water proportion of the first cooling water circuit that is conducted via the bypass. The position of the control valve is controlled such that an advance cooling water temperature corresponds to a set point value. The rotational speed of the sea water pump is controlled based on the position of the control valve.

Disclosed is a water intake system for a floating vessel in a body of water, which includes within the hull of the vessel an intake compartment for taking in water from the body of water and a distribution compartment for distributing and supplying the water to one or more consumer units within the floating vessel. The intake compartment is arranged below a lowest operational draught of the vessel and has an inlet in a bottom region of the intake compartment. The intake compartment is coupled by a conduit to the distribution compartment for allowing water to flow into the distribution compartment. The water intake system further includes a water lift hose that is connected to the inlet and is extendible below the hull of the vessel.

Embodiments of a jet pump system are disclosed where certain embodiments comprise an inlet component, an electronic controller which is cooled via the inflow of water through the inlet component, a combined motor impeller system positioned adjacent to the outflow aperture of the inlet component, and a nozzle pump positioned adjacent to the outflow of the motor impeller system.

Embodiments of a jet pump system are disclosed where certain embodiments comprise an inlet component, an electronic controller which is cooled via the inflow of water through the inlet component, a combined motor impeller system positioned adjacent to the outflow aperture of the inlet component, and a nozzle pump positioned adjacent to the outflow of the motor impeller system.

Embodiments of a jet pump system are disclosed where certain embodiments comprise an inlet component, an electronic controller which is cooled via the inflow of water through the inlet component, a combined motor impeller system positioned adjacent to the outflow aperture of the inlet component, and a nozzle pump positioned adjacent to the outflow of the motor impeller system.