Watercraft

Abstract

To provide a ship capable of reducing restriction of arrangement of a fuel tank and a pump and transferring methanol as fuel from the fuel tank by the pump while suppressing vaporization of the methanol.SOLUTION: A ship includes a hull having a pair of broadsides and a bottom, a lowermost deck provided in the hull and defining a double bottom space between the lowermost deck and the bottom, a tank at least partially provided in the double bottom space and capable of storing methanol as fuel, a pump provided outside the tank and below the lowermost deck in the hull and pumping the methanol in the tank, and a combustion device provided in the hull and to which the methanol pumped by the pump is supplied.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to marine vessels. [Background technology]

[0002] A double-hull (double bottom) structure is known as a structure that increases the longitudinal strength of a ship's hull. For example, Patent Document 1 discloses a double-hull cargo ship with a two-layer bottom structure, with a fuel tank for storing fuel in the upper layer and a bottom ballast tank in the lower layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-203980 Summary of the Invention [Problem to be solved by the invention]

[0004] Meanwhile, ships using methanol as fuel are becoming more common. Methanol fuel has the advantage of reducing the sulfur oxides and nitrogen oxides generated during combustion. However, because methanol is highly volatile and easily vaporizes under negative pressure, care must be taken to avoid negative pressure. Therefore, when transferring methanol from a ship's methanol fuel tank using a pump, it is necessary to take measures such as positioning the methanol fuel tank vertically above the pump or installing a submerged pump inside the methanol fuel tank.

[0005] For example, if the methanol fuel tank is located vertically above the pump, the position of the ship's center of gravity may be raised, and space for cargo, etc. may be reduced. On the other hand, when a submerged pump is used, the cost per pump increases. Furthermore, one submerged pump must be provided for each methanol fuel tank, which increases costs. Furthermore, because the submerged pump is provided inside the methanol fuel tank, maintenance is less easy compared to a pump provided outside the methanol fuel tank. Therefore, there is a need for a method that allows methanol to be used as a fuel while mitigating the restrictions on the placement of the fuel tank and pump.

[0006] The present disclosure aims to provide a ship that can reduce restrictions on the placement of fuel tanks and pumps and can prevent methanol transported by the pump from evaporating. [Means for solving the problem]

[0007] In order to solve the above problems, the ship disclosed herein comprises a hull having a pair of side walls and a bottom, a lowermost deck located within the hull and forming a double-bottom space between it and the bottom, a tank at least partially located within the double-bottom space and capable of storing methanol as fuel, a pump located outside the tank below the lowermost deck within the hull and pressurizing the methanol in the tank, and a combustion device located on the hull and supplied with the methanol pressurized by the pump. [Effects of the Invention]

[0008] According to the ship of the present disclosure, it is possible to provide a ship that can reduce restrictions on the placement of fuel tanks and pumps and can prevent methanol transported by the pump from evaporating. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a configuration diagram of a ship according to a first embodiment of the present disclosure. [Figure 2] FIG. 10 is a configuration diagram of a ship according to a modified example of the first embodiment of the present disclosure. [Figure 3]FIG. 10 is a configuration diagram of a ship according to a second embodiment of the present disclosure. [Figure 4] FIG. 10 is a configuration diagram of a ship according to a modified example of the second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] A boat 1 according to an embodiment of the present disclosure will be described below with reference to Figures 1 to 4. Note that Figures 1 to 4 each show an enlarged view of a main part, and the size and positional relationship relative to the entire boat 1 are different from the actual size and positional relationship.

[0011] First Embodiment Hereinafter, a first embodiment of a vessel 1 according to the present disclosure will be described in detail with reference to FIG.

[0012] <Overall configuration of the ship> The ship 1 of this embodiment is capable of sailing using methanol as fuel. As shown in Fig. 1, the ship 1 of this embodiment includes a hull 10, a tank 30, a pump 40, piping 60, and a combustion device 50. The type of ship 1 is not limited to a specific one. Examples of the type of ship 1 include carriers of liquefied gases such as liquefied natural gas (LNG), liquefied carbon dioxide, and liquefied ammonia, ferries, roll-on / roll-off ships (RORO ships), and pure car and truck carriers (PCTCs).

[0013] <Hull> The hull 10 comprises a pair of side walls 11 that form its outer hull, a bottom wall 12, and an upper deck. The side walls 11 have a pair of side wall shells that form the port and starboard sides, respectively. The bottom wall 12 has a bottom wall shell that connects the side walls 11. In this embodiment, the upper deck is an exposed deck whose upper surface facing upward in the vertical direction D1 faces the outside. In the following, directions are defined as follows: The direction perpendicular to the vertical direction D1 is the horizontal direction. The horizontal direction in which the bow and stern are aligned is referred to as the bow-stern direction D2, and the horizontal direction in which the pair of side walls 11 face each other is referred to as the ship's beam direction D3. The bow-stern direction D2 and the ship's beam direction D3 are perpendicular to each other.

[0014] The hull 10 also has multiple decks inside, including a lowermost deck 20. The lowermost deck 20 is the deck located at the lowest level among the multiple decks. The lowermost deck 20 forms a double bottom together with the ship's bottom 12. The lowermost deck 20 is located at a distance from the ship's bottom 12 in the vertical direction D1. The lowermost deck 20 is located higher than the ship's bottom 12 in the vertical direction D1. In other words, the lowermost deck 20 is located so as to define a double bottom space 24 between itself and the ship's bottom 12.

[0015] The double bottom space 24 extends in the bow-stern direction D2 and the width direction D3. A ballast tank, a cofferdam, a tank, etc. can be placed in the double bottom space 24. In this embodiment, the double bottom space 24 is provided with a tank 30 capable of storing methanol as a fuel, which will be described later.

[0016] The hull 10 also has a fuel conditioning chamber 25 formed as a compartment within it. The fuel conditioning chamber 25 is located on the lowermost deck 20. The fuel conditioning chamber 25 is a managed room that can appropriately treat vaporized fuel without leaking into the surrounding area, for example, in the event of a fuel leak within the room. The fuel conditioning chamber 25 is equipped with, for example, a heat exchanger and sensors for monitoring and controlling various parameters.

[0017] The fuel regulation chamber 25 of this embodiment includes a fuel regulation chamber main body 26 and a recess 21. The fuel regulation chamber main body 26 is disposed on the lowermost deck 20. The fuel regulation chamber main body 26 houses the above-mentioned heat exchanger, sensors, etc. The recess 21 is formed such that a portion of the lowermost deck 20 forming the bottom surface of the fuel regulation chamber main body 26 is recessed downward in the vertical direction D1. The space within the fuel regulation chamber main body 26 and the space within the recess 21 are in communication.

[0018] The recess 21 is formed to extend in the bow-stern direction D2 and the ship's width direction D3. The recess 21 has a bottom 22 extending in the bow-stern direction D2 and the ship's width direction D3, and side portions 23 rising upward from the periphery of the bottom 22 and extending in the vertical direction D1. The bottom 22 is disposed at a distance from the ship's bottom 12 in the vertical direction D1. A pump 40, which will be described later, can be installed inside the recess 21.

[0019] <Tank> The tank 30 is capable of storing liquefied gas therein. In this embodiment, the tank 30 is capable of storing methanol as fuel for the combustion device 50. The tank 30 may also store liquefied gas that is not used for the navigation of the ship 1. In addition to methanol, examples of liquefied gas that can be stored in the tank 30 include carbon dioxide, LNG, ammonia, etc.

[0020] The tank 30 is disposed within the hull 10. In this embodiment, the tank 30 is configured as part of the hull. Piping 60, which will be described later, is connected to the horizontal surface of the tank 30. At least a portion of the tank 30 is disposed in the double bottom space 24. The tank 30 in this embodiment is disposed so as to penetrate the lowermost deck 20 from top to bottom. The uppermost end of the tank 30 in the vertical direction D1 is disposed above the lowermost deck 20 in the vertical direction D1. The tank 30 is not limited to being configured as part of the hull. For example, the tank 30 may be an independent tank.

[0021] <Pump> The pump 40 is provided so as to be able to pump out methanol in the tank 30. The pump 40 is able to suck out methanol in the tank 30. The pump 40 pumps out the sucked out methanol towards the combustion device 50. The pump 40 is arranged inside the hull 10 but outside the tank 30. The pump 40 is provided in the space within the recess 21. In other words, the pump 40 is provided inside the hull 10, below the lowermost deck 20 in the vertical direction D1. The pump 40 is supported by a base (not shown) provided within the recess 21, specifically on the bottom 22. The pump 40 is fixed so as not to be able to move relative to the hull 10.

[0022] <Combustion equipment> The combustion device 50 is provided inside the hull 10. The combustion device 50 is a device that operates using methanol as fuel. Examples of the combustion device 50 include a main engine, a power generation engine, and a boiler. In this embodiment, the combustion device 50 is the main engine. The number of combustion devices 50 provided in the hull 10 is not limited to one. For example, a configuration in which multiple combustion devices 50 are provided may also be used.

[0023] The combustion unit 50, which is the main engine, is housed in the engine room outside the fuel adjustment room 25. Methanol is supplied to the combustion unit 50 under pressure by a pump 40. The combustion unit 50 is an engine (internal combustion engine) that burns methanol stored in a tank 30 as fuel. The combustion unit 50 converts thermal energy generated by the combustion of methanol into rotational energy that drives a propeller disposed in the hull 10. The combustion unit 50 is connected to the pump 40 by a pipe 60. The combustion unit 50 is located downstream of the pump 40 in terms of the flow of methanol.

[0024] <Piping> The piping 60 is provided to allow methanol to flow through it. The piping 60 can send methanol in a liquid state from the tank 30 to the combustion device 50. The piping 60 has a structure such as a double piping structure to prevent methanol leakage (not shown). The piping 60 is equipped with valves, meters, joints, etc. as necessary. The piping 60 has a first piping 61 and a second piping 62.

[0025] The first pipe 61 connects the tank 30 and the pump 40. The first pipe 61 extends in the fore-and-stern direction D2. The first pipe 61 extends, penetrating the side portion 23 of the recessed portion 21 in the fore-and-stern direction D2. The second pipe 62 connects the pump 40 and the combustion device 50. In this embodiment, the second pipe 62 extends upward from the pump 40 in the vertical direction D1 and is connected to the combustion device 50 through the fuel adjustment chamber 25. Note that the second pipe 62 is not limited to this form. For example, the second pipe 62 may extend, penetrating the side portion 23 of the recessed portion 21 in the fore-and-stern direction D2 or the ship's width direction D3, or may be connected to the combustion device 50 without passing through the fuel adjustment chamber 25.

[0026] In this embodiment, the tank 30, the piping 60, and the pump 40 are positioned relative to one another as follows: The pump 40 is disposed apart from the tank 30 in the horizontal direction. The pump 40 is disposed below the uppermost end of the tank 30 in the vertical direction D1. The first piping 61 is disposed below the uppermost end of the pump 40 in the vertical direction D1.

[0027] <Action and effect> In the vessel 1 described above, at least a portion of the tank 30 capable of storing methanol as fuel is provided inside the double bottom space 24. In addition, a pump 40 for pumping the methanol is disposed outside the tank 30 and below the lowermost deck 20. This brings the liquid level of the methanol contained in the tank 30 closer to the inlet of the pump 40 in the vertical direction D1. This prevents the inlet pressure of the pump 40, which sucks methanol, from decreasing excessively, as occurs when the inlet of the pump 40 is positioned above the liquid level of the methanol in the vertical direction D1 and a head (hydraulic head) acts. Furthermore, because the pump 40 is provided outside the tank 30, the inlet pressure of the pump 40 can be prevented from decreasing excessively even without a configuration such as a submerged pump. This eliminates the need to place the tank 30 at a higher position or to place the pump 40 inside the tank 30, thereby reducing restrictions on the placement of the tank 30 and the pump 40. Furthermore, evaporation of the liquid methanol sucked into the pump 40 can be prevented, thereby preventing gas from flowing into the pump 40.

[0028] In addition, in the ship 1, the recess 21 is formed by recessing a portion of the lowermost deck 20 downward. The pump 40 is provided in the recess 21 thus formed. This allows the pump 40, which is located below the lowest deck 20, to be easily accessed from the compartment immediately above the lowest deck 20. Therefore, the pump 40 can be positioned below the lowest deck 20, similar to the tank 30, while reducing the burden on workers when performing maintenance on the pump 40.

[0029] In the above-described boat 1, the recess 21 forms a part of the fuel adjustment chamber 25, and the recess 21 and the fuel adjustment chamber main body 26 are in communication with each other. That is, the pump 40 is disposed in the fuel adjustment chamber 25. This eliminates the need to connect the pump 40 and the fuel adjustment chamber 25 with a double pipe or to take measures to prevent methanol leakage from a compartment that houses the pump 40 separate from the fuel adjustment chamber 25. This makes it possible to suppress increases in the manufacturing costs of the boat 1.

[0030] The tank 30 of this embodiment is provided so as to penetrate the lowermost deck 20 in the vertical direction D1. This makes it possible to place a tank 30 with a larger capacity while effectively utilizing the double bottom space 24 as storage space for the tank 30. In addition, by locating a portion of the tank 30 above the lowermost deck 20 in the vertical direction D1, the maintainability of the tank 30 can also be improved.

[0031] Furthermore, in this embodiment, the pump 40 is not provided inside the tank 30, such as a submerged pump. Therefore, the pump 40 can be accessed more easily than if the pump 40 were provided inside the tank 30. Therefore, the maintainability of the pump 40 can be improved.

[0032] Furthermore, the arrangement of the tanks 30 and pumps 40 as in this embodiment allows for a larger space to be provided above the horizontal plane of the lowermost deck 20. This allows for a larger space to be provided for loading cargo, for example. Furthermore, by positioning the tanks 30 and pumps 40 within the hull 10 closer to the bottom 12 in the vertical direction D1, the center of gravity of the ship 1 can be lowered.

[0033] <Modification of the first embodiment> Next, a modified example of the first embodiment will be described with reference to Fig. 2. In the modified example of the first embodiment, the same components as those in the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted.

[0034] A ship 1A according to a modification of the first embodiment differs from the first embodiment in the arrangement of tanks 30A and the structure of the lowermost deck 20A. The tank 30A according to the modification of the first embodiment is entirely disposed inside the double bottom space 24. The lowermost deck 20A according to the modification of the first embodiment is provided above the tank 30A in the vertical direction D1. The lowermost deck 20A and the tank 30A are disposed spaced apart in the vertical direction D1. However, this is not limited to this configuration, and for example, the lowermost deck 20A and the tank 30A may be in contact with each other.

[0035] <Action and effect> In the vessel 1A according to a modification of the first embodiment, a tank 30A capable of storing methanol as fuel is disposed below the lowermost deck 20A in the vertical direction D1. As a result, the tank 30A is not disposed in the space above the lowermost deck 20A in the vertical direction D1. Therefore, it is possible to provide a large space above the lowermost deck 20A in the vertical direction D1.

[0036] Second Embodiment Next, a second embodiment will be described with reference to Fig. 3. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0037] A vessel 1B according to the second embodiment differs from the first embodiment in the arrangement of a pump 40A and the structure of a lowermost deck 20B. The lowermost deck 20B according to the second embodiment does not have the recess 21 of the first embodiment. In the second embodiment, the pump 40A is arranged inside the double bottom space 24. The pump 40A is supported by a base (not shown) provided inside the double bottom space 24. The pump 40A is fixed so as not to move relative to the hull 10. Furthermore, the first piping 61 according to the second embodiment extends in the bow-stern direction D2, as in the first embodiment.

[0038] <Action and effect> In the vessel 1B according to the second embodiment, the pump 40A is disposed inside the double bottom space 24. This eliminates the need to form a recess 21 in the lowermost deck 20B for disposing the pump 40A, thereby simplifying the structure of the lowermost deck 20B.

[0039] <Modification of the second embodiment> Next, a modified example of the second embodiment will be described with reference to Fig. 4. In the modified example of the second embodiment, the same components as those in the first embodiment, the modified example of the first embodiment, and the second embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted.

[0040] The vessel 1C according to the modification of the second embodiment differs from the first embodiment in the arrangement of the pump 40A, the structure of the lowermost deck 20C, and the arrangement of the tank 30A. The tank 30A is the same as that of the modification of the first embodiment. The lowermost deck 20C according to the second embodiment does not have the recess 21 of the first embodiment. Moreover, the lowermost deck 20C does not have the penetration portion of the first embodiment. That is, the lowermost deck 20C is provided above the tank 30A in the vertical direction D1. Moreover, the lowermost deck 20C and the tank 30A are arranged spaced apart in the vertical direction D1.

[0041] <Action and effect> In the marine vessel 1C according to the second embodiment, a tank 30A capable of storing methanol as fuel is disposed below the lowermost deck 20C in the vertical direction D1. The pump 40A is disposed inside the double bottom space 24. This eliminates the need for the tank 30A to be disposed in the space above the lowermost deck 20C in the vertical direction D1. Furthermore, there is no need to form a recess 21 in the lowermost deck 20C for disposing the pump 40A. This allows for a larger space to be provided above the lowermost deck 20C in the vertical direction D1. Furthermore, the structure of the lowermost deck 20C can be simplified.

[0042] <Other embodiments> Each embodiment of the present disclosure has been described above in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present disclosure.

[0043] In the ships 1, 1A, 1B, and 1C according to an embodiment, equipment other than the piping 60 may be provided between the pumps 40, 40A and the combustion device 50. For example, a small tank capable of storing methanol as fuel may be provided between the pumps 40, 40A and the combustion device 50.

[0044] Furthermore, a combination of multiple embodiments of the present disclosure may be used. For example, a ship may be provided with a tank 30 that penetrates the lowest deck in the vertical direction D1 and a tank 30A that is provided below the lowest deck. This allows for increased flexibility in designing the interior space of the hull 10 while ensuring the required fuel capacity.

[0045] Furthermore, the tank 30, 30A according to one embodiment may be connected to the first pipe 61 on a surface facing downward in the vertical direction D1.

[0046] Furthermore, a plurality of tanks 30, 30A according to one embodiment may be provided. For example, two tanks 30, 30A, each capable of storing methanol as fuel, may be arranged so as not to abut on each other. According to this aspect, even when there are two tanks 30, 30A, it is sufficient to provide one pump 40, 40A. This makes it possible to reduce the number of pumps 40, 40A and reduce the manufacturing cost of the vessel 1. Note that three or more tanks 30, 30A may be provided.

[0047] Furthermore, according to one embodiment, a plurality of pumps 40, 40A may be provided. For example, the number of tanks 30, 30A and the number of pumps 40, 40A may be the same, or the number of pumps 40, 40A may be greater than the number of tanks 30, 30A.

[0048] Furthermore, the recess 21 according to one embodiment may be provided so as not to communicate with the fuel regulation chamber 25. In other words, the recess 21 may not be formed in the fuel regulation chamber 25. In this embodiment, the pump 40 is provided in the space within the recess 21. That is, the pump 40 is disposed inside the hull 10 and outside the fuel regulation chamber 25.

[0049] <Additional Notes> The ships 1, 1A, 1B, and 1C described in each embodiment can be understood, for example, as follows.

[0050] (1) A ship 1, 1A, 1B, 1C according to a first embodiment comprises a hull 10 having a pair of side walls 11 and a bottom 12, a lowermost deck 20, 20A, 20B, 20C provided within the hull 10 and defining a double bottom space 24 between the hull 10 and the bottom 12, tanks 30, 30A at least a portion of which are provided within the double bottom space 24 and capable of storing methanol as fuel, pumps 40, 40A provided outside the tanks 30, 30A and below the lowermost deck 20, 20A, 20B, 20C within the hull 10 for pumping the methanol in the tanks 30, 30A, and a combustion device 50 provided in the hull 10 to which the methanol pumped by the pumps 40, 40A is supplied.

[0051] According to the above configuration, the tanks 30, 30A and the pumps 40, 40A are both positioned within the hull 10 close to the bottom 12 in the vertical direction D1. This makes it possible to prevent negative pressure from occurring when methanol is transferred from the tanks 30, 30A to the pumps 40, 40A, even when methanol is used as fuel. Therefore, the ship 1 of this aspect can alleviate restrictions on the placement of the tanks 30, 30A and the pumps 40, and can prevent the methanol transferred by the pumps 40, 40A from evaporating.

[0052] (2) The ships 1, 1A, 1B, and 1C according to the second aspect are the ships 1, 1A, 1B, and 1C of (1), in which a recess 21 is formed by recessing a portion of the lowermost deck 20, 20A, 20B, and 20C downward, and the pump 40 is provided in the space within the recess 21.

[0053] According to the above configuration, the tank 30 can be disposed further downward in the vertical direction D1 because the pump 40 is provided in the recess 21. Therefore, the degree of freedom in disposing the tank 30 and the pump 40 in the vessel 1 can be further increased.

[0054] (3) The ships 1, 1A, 1B, and 1C according to the third aspect are the ships 1, 1A, 1B, and 1C of (2), and are provided with a fuel adjustment chamber 25 having a fuel adjustment chamber main body 26 located on the lowest deck 20, 20A, 20B, and 20C, and the recess 21 communicating with the fuel adjustment chamber main body 26.

[0055] According to the above configuration, the space within the recess 21 and the fuel adjustment chamber 25 are connected to each other. That is, the pump 40 is disposed in the fuel adjustment chamber 25. This eliminates the need to provide a separate space for controlling the pump 40. By integrating the fuel adjustment chamber 25 and the space in which the pump 40 is disposed, the number of spaces to be managed within the hull 10 can be reduced.

[0056] (4) The ships 1, 1A, 1B, and 1C according to the fourth aspect are the ships 1, 1A, 1B, and 1C according to (1) to (3), and the tank 30 is arranged to penetrate the lowermost deck 20, 20A, 20B, and 20C in the vertical direction.

[0057] According to the above configuration, the tank 30 is provided so as to penetrate the lowermost decks 20, 20A, 20B, 20C in the vertical direction D1. The tank 30 is also arranged so that at least a portion of the tank 30 is provided in the double bottom space 24. This makes it possible to arrange a tank 30 with a large capacity. [Explanation of symbols]

[0058] 1, 1A, 1B, 1C Vessel 10 Hull 11 side 12 Ship's Bottom 20, 20A, 20B, 20C Lower deck 21 Recess 22 Bottom 23 Side 24 Double bottom space 25 Fuel adjustment room 26 Fuel adjustment chamber body 30, 30A tank 40, 40A pump 50 Combustion Device 60 Piping 61 First Piping 62 Second piping D1 Vertical direction D2 Fore and aft direction D3 Ship width direction

Claims

1. a hull having a pair of sides and a bottom; A lowermost deck is provided in the hull and defines a double bottom space between the hull and the bottom of the ship. a tank at least a portion of which is provided within the double bottom space and capable of storing methanol as fuel; a pump that is provided outside the tank and below the lowermost deck within the hull, and that pumps out the methanol in the tank; a combustion device provided on the hull and supplied with the methanol pressure-fed by the pump; A vessel equipped with:

2. A recess is formed so that a portion of the lowest deck is recessed downward, The watercraft according to claim 1, wherein the pump is provided in a space within the recess.

3. The ship according to claim 2 , further comprising a fuel regulation chamber having a fuel regulation chamber main body located on the lowermost deck and the recess communicating with the fuel regulation chamber main body.

4. The ship according to any one of claims 1 to 3, wherein the tank is provided so as to penetrate the lowermost deck in the vertical direction.

Images