The present invention relates to a gas treatment system and a ship including the same. The gas treatment system treats liquefied gas as heavier hydrocarbons or ammonia. The gas treatment system includes: a fuel tank storing liquefied gas as a fuel to be supplied to a propulsion engine of a ship; a liquefied gas supply line supplying the liquefied gas of the fuel tank in a liquid phase to the propulsion engine, the liquefied gas supply line having a high pressure pump provided thereon; a reliquefaction apparatus liquefying boil-off gas generated in a cargo tank storing liquefied gas; and a liquefied gas collection line collecting the liquid liquefied gas discharged from the propulsion engine upstream of the high pressure pump. The reliquefaction apparatus transfers the liquefied boil-off gas to the fuel tank, thereby allowing the liquefied boil-off gas to be supplied to the propulsion engine by the high pressure pump.

Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG discharged from a storage tank as a refrigerant; a bypass line through which the BOG is supplied to the compressor after bypassing the heat exchanger; a second valve disposed on a second supply line through which the BOG used as the refrigerant in the heat exchanger is supplied to the compressor, the second valve regulating a flow rate of fluid and opening/closing of the second supply line; and a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger, wherein the compressor includes at least one oil-lubrication type cylinder and the bypass line is joined to the second supply line downstream of the second valve.

Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG discharged from a storage tank as a refrigerant; a bypass line through which the BOG is supplied to the compressor after bypassing the heat exchanger; a second valve disposed on a second supply line through which the BOG used as the refrigerant in the heat exchanger is supplied to the compressor, the second valve regulating a flow rate of fluid and opening/closing of the second supply line; and a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger, wherein the compressor includes at least one oil-lubrication type cylinder and the bypass line is joined to the second supply line downstream of the second valve.

The invention relates to a motorization system for an electrically assisted craft which is intended to allow a user to be transported on water, the invention being used particularly in the field of surfboards, paddleboards or sailboards, and in the field of kayaks or canoes.

The electric motorization system is configured to be connected to an electrical energy source and comprises, on the one hand, a watertight enclosure 1 which is intended to be integrated in or on a craft, in which enclosure 1 a rotor 2 and a stator 3, 7 are arranged, and, on the other hand, a shaft 4 which is connected at a first end to the rotor 2 and which protrudes in a watertight manner outside the enclosure 1 at a second end opposite its first end. The shaft 4 can be connected at its second end to propulsion means of a craft, such as a propeller, so that when the system is supplied with electrical energy, the rotor 2 is rotated and drives the shaft 4 with this rotation.

The system also comprises cooling means 5 which themselves comprise at least one first elongate assembly 5, which is at least partially made of metal, and a first end of which is arranged inside the enclosure 1, the elongate assembly 5 protruding in a watertight manner outside the enclosure 1 at a second end opposite its first end so as to allow conduction of the heat from the inside to the outside of the enclosure 1 along the first elongate assembly 5.

The invention relates to a motorization system for an electrically assisted craft which is intended to allow a user to be transported on water, the invention being used particularly in the field of surfboards, paddleboards or sailboards, and in the field of kayaks or canoes.

The electric motorization system is configured to be connected to an electrical energy source and comprises, on the one hand, a watertight enclosure 1 which is intended to be integrated in or on a craft, in which enclosure 1 a rotor 2 and a stator 3, 7 are arranged, and, on the other hand, a shaft 4 which is connected at a first end to the rotor 2 and which protrudes in a watertight manner outside the enclosure 1 at a second end opposite its first end. The shaft 4 can be connected at its second end to propulsion means of a craft, such as a propeller, so that when the system is supplied with electrical energy, the rotor 2 is rotated and drives the shaft 4 with this rotation.

The system also comprises cooling means 5 which themselves comprise at least one first elongate assembly 5, which is at least partially made of metal, and a first end of which is arranged inside the enclosure 1, the elongate assembly 5 protruding in a watertight manner outside the enclosure 1 at a second end opposite its first end so as to allow conduction of the heat from the inside to the outside of the enclosure 1 along the first elongate assembly 5.

Disclosed herein are a fuel supply system for ships and a fuel supply method using the same. The fuel supply method includes: 1) supplying an excess amount of liquefied gas as fuel to an incompressible fluid-fueled engine (E); 2) cooling unconsumed fuel discharged from the engine (E) through heat exchange with liquefied gas discharged from a storage tank (T); 3) returning the unconsumed fuel discharged from the engine (E) and having been cooled through heat exchange in step 2) to the storage tank (T); and 4) supplying the liquefied gas discharged from the storage tank (T) and having been used as refrigerant for heat exchange in step 2) to the engine (E). The fuel supply method can prevent cavitation in the engine (E) by supplying the excess amount of liquefied gas sufficient to accommodate variation in load of the engine (E) as fuel to the engine (E).

Disclosed herein are a fuel supply system for ships and a fuel supply method using the same. The fuel supply method includes: 1) supplying an excess amount of liquefied gas as fuel to an incompressible fluid-fueled engine (E); 2) cooling unconsumed fuel discharged from the engine (E) through heat exchange with liquefied gas discharged from a storage tank (T); 3) returning the unconsumed fuel discharged from the engine (E) and having been cooled through heat exchange in step 2) to the storage tank (T); and 4) supplying the liquefied gas discharged from the storage tank (T) and having been used as refrigerant for heat exchange in step 2) to the engine (E). The fuel supply method can prevent cavitation in the engine (E) by supplying the excess amount of liquefied gas sufficient to accommodate variation in load of the engine (E) as fuel to the engine (E).

A watercraft (10) including a board (12), a mast (16) extending below the board, (12) the mast (16) carrying a foil (20) and a propeller (30) that is driven by a motor (32), the motor (32) being carried in a tube (18) connected to or extending from the mast (16), wherein a motor controller (34) is also positioned within the tube (18). In this manner, heat generated by the motor controller during use is dissipated into the water through which the watercraft is travelling. The watercraft (10) may also have a receptacle for holding lubricant, the receptacle being located above the motor, wherein the mast has a conduit that provides fluid communication between the receptacle and the lubricant lubricating the motor and/or driveshaft such that lubricant in the receptacle provides a hydrostatic head of pressure to prevent or minimise water ingress around a propeller seal or a driveshaft seal located adjacent a region where the driveshaft exits into the water.

A draining arrangement of a propulsion unit of a marine vessel. The propulsion unit includes a shell structure. The shell structure limiting at least one bottom section configured to receive liquids. The draining arrangement including a pneumatically operated drainage arrangement including an intermediate tank within the shell structure, a pressurizing arrangement functionally connected to the intermediate tank and configured to selectively provide a vacuum in the intermediate tank or an excess pressure in the intermediate tank, a first liquid line that is provided between the intermediate tank and said at least one bottom section, and a second liquid to line that is provided between the intermediate tank and a collector arrangement within the hull of the marine vessel.

A draining arrangement of a propulsion unit of a marine vessel. The propulsion unit includes a shell structure. The shell structure limiting at least one bottom section configured to receive liquids. The draining arrangement including a pneumatically operated drainage arrangement including an intermediate tank within the shell structure, a pressurizing arrangement functionally connected to the intermediate tank and configured to selectively provide a vacuum in the intermediate tank or an excess pressure in the intermediate tank, a first liquid line that is provided between the intermediate tank and said at least one bottom section, and a second liquid to line that is provided between the intermediate tank and a collector arrangement within the hull of the marine vessel.