Methanol-fueled ship

Abstract

Provided is a methanol-fueled ship that can reduce the weight of a hull while maintaining the volume of a fuel tank. A methanol-fueled ship 1 comprises: a pair of partition wall steel plates 2 disposed so as to form a prescribed gap with respect to hull partition walls (bulkheads 17); a pair of side wall steel plates 3 disposed so as to form a prescribed gap with respect to hull side walls 18; demarcating steel plates 4 that demarcate, to the front and rear, a part of a longitudinal structures (top side 12a, hopper 12b, double bottom 12c, etc.) of the hull; and a top part steel plate 5 disposed so as to form a prescribed gap with respect to an upper deck 11. The methanol-fueled ship 1 uses an internal space, which is formed by the partition wall steel plates 2, the side wall steel plates 3, and the longitudinal structures (here, the top side 12a, the hopper 12b, and the double bottom 12c) as a fuel tank 20.

Description

Methanol-fueled ship

[0001] The present invention relates to a methanol-fueled ship having a hull that can be propelled by methanol fuel.

[0002] In recent years, zero-emissions, which reduce the discharge of pollutants and waste, has been proposed as a means of environmental conservation. For example, the roadmap for achieving zero-emissions in international shipping considers the use of carbon-recycled fuels (methane, methanol, dimethyl ether, etc.).

[0003] Carbon recycled fuel is a fuel that uses carbon recycling technology (CO ２ Carbon recycled fuel is a fuel that is artificially produced using a technology called "carbon separation and recovery for reuse." ２ However, by using carbon recycling technology, CO ２ This can reduce emissions.

[0004] For example, Patent Document 1 discloses that an internal combustion engine that can be operated using methanol as fuel is disposed inside the engine room, a methanol fuel tank, a methanol supply system, and a valve unit are disposed on the upper deck, a methanol drain tank is provided outside the engine room, and the piping portions disposed inside the engine room are configured as double pipes for a second pipe that supplies methanol from the methanol supply system to the valve unit, a third pipe that supplies methanol from the valve unit to the internal combustion engine, and a fourth pipe that discharges methanol drain from the internal combustion engine to the methanol drain tank.

[0005] Japanese Patent Application Laid-Open No. 2015-221645

[0006] As described in Patent Document 1, when a methanol fuel tank is placed on the upper deck, it is difficult to ensure a sufficient tank volume because the fuel volume (volume per calorific value) of methanol is about 2.4 times that of heavy oil. Also, when a methanol fuel tank is placed below the upper deck, a cofferdam (protective compartment) is required around the methanol fuel tank, which poses the problem of increasing the weight of the ship due to the additional members.

[0007] The present invention was devised in view of the above problems, and has as its object to provide a methanol-fueled ship that can reduce the hull weight while ensuring sufficient fuel tank capacity.

[0008] According to the present invention, there is provided a methanol-fueled ship having a hull that can be propelled by methanol fuel, comprising a pair of bulkhead steel plates arranged to form a predetermined gap with a hull bulkhead, a pair of sidewall steel plates arranged to form a predetermined gap with the hull sidewall, and compartment steel plates that divide a part of the hull longitudinal structure into front and rear, wherein the internal space formed by the bulkhead steel plates, the sidewall steel plates, and the longitudinal structure is used as a fuel tank, and the bulkhead steel plates, the sidewall steel plates, and the compartment steel plates are configured to form a cofferdam that surrounds the outer periphery of the fuel tank.

[0009] The longitudinal structure may be a hopper of a cargo hold, a topside of a cargo hold, a double bottom or a double wall structure of a double hull.

[0010] The methanol-fueled ship may include a top steel plate arranged to form a predetermined gap between the top steel plate and the upper deck.

[0011] The methanol-fueled ship may be configured so that the hopper, the double bottom, or the double-wall structure located below the fuel tank is used as the fuel tank.

[0012] The fuel tank may be located amidships or in front of the engine room.

[0013] The methanol-fueled ship may include a cofferdam or fuel supply equipment room located on the upper deck directly above the fuel tank.

[0014] The methanol-fueled ship may include a fuel supply device room located on the upper deck directly above the fuel tank and the cofferdam, and a fuel supply pipe that supplies methanol fuel from the fuel tank to the main engine may be configured to pass through the fuel supply device room and the cofferdam.

[0015] The methanol-fueled vessel may be a bulk carrier.

[0016] In the methanol-fueled ship according to the present invention described above, by arranging bulkhead steel plates and sidewall steel plates to use part of the hull structure as a fuel tank and to use part of the hull structure (longitudinal structure) as a cofferdam, it is possible to reduce the hull weight while ensuring the capacity of the fuel tank.

[0017]

[0023] Figures 1A and 1B are diagrams showing a methanol-fueled ship according to a first embodiment of the present invention, where (A) is a side view and (B) is a plan view of the upper deck. Figures 1A and 1B are cross-sectional views of the methanol-fueled ship shown in Figure 1, where (A) is the cargo hold section and (B) is the fuel tank section. Figures 1A and 1B are diagrams showing modified fuel tanks, where (A) is a first modified example, (B) is a second modified example, and (C) is a third modified example. Figures 1A and 1B are cross-sectional views of a methanol-fueled ship according to a second embodiment of the present invention, where (A) is the cargo hold section and (B) is the fuel tank section. Figures 1A and 1B are cross-sectional views of a methanol-fueled ship according to a third embodiment of the present invention, where (A) is a side view and (B) is a plan view of the upper deck. Figures 1A and 1B are cross-sectional views of the methanol-fueled ship shown in Figure 5, where (A) is the cargo hold section, (B) is the fuel tank section, and (C) is a modified example. Figures 1A and 1B are diagrams showing a methanol-fueled ship according to a fourth embodiment of the present invention, where (A) is a side view and (B) is a plan view of the upper deck. 8A and 8B are cross-sectional views of the methanol-fueled ship shown in FIG. 7, where (A) shows the cargo hold section and (B) shows the fuel tank section. Fig. 8 is a schematic configuration diagram showing a modified example of a methanol-fueled ship according to a fourth embodiment.

[0018] Hereinafter, embodiments of the present invention will be described with reference to Figures 1 to 9. Figure 1 shows a methanol-fueled ship according to a first embodiment of the present invention, where (A) is a side view and (B) is a plan view of the upper deck. Figure 2 is a cross-sectional view of the methanol-fueled ship shown in Figure 1, where (A) shows the cargo hold section and (B) shows the fuel tank section.

[0019] The methanol-fueled ship 1 has a hull that can be propelled by methanol fuel, and is equipped with a pair of bulkhead steel plates 2 arranged to form a predetermined gap with the hull bulkhead (bulkhead 17), a pair of sidewall steel plates 3 arranged to form a predetermined gap with the hull sidewall 18, partition steel plates 4 that divide part of the hull longitudinal structure (topside 12a, hopper 12b, double bottom 12c, etc.) into fore and aft parts, and a top steel plate 5 arranged to form a predetermined gap with the upper deck 11. In this specification, the fore-aft direction means the longitudinal direction of the hull, with the bow side being the front and the stern side being the rear.

[0020] Methanol fuel may be derived from recycled carbon or from fossil fuels. Since methanol has a fuel volume (volume per calorific value) that is approximately 2.4 times that of heavy oil, sufficient volume can be easily secured by storing it in the hull (hold) below the upper deck. Methanol fuel refers to fuel for the main engine that is primarily composed of methanol.

[0021] The methanol-fueled ship 1 is, for example, a bulk carrier. A bulk carrier generally includes a plurality of cargo holds 12 for storing cargo below an upper deck 11 (hold), an engine room 13 located aft of the hold, an accommodation space 14 located above the engine room 13, a deck crane 15 located on the upper deck, and a hatch cover 16 for closing the upper opening of the cargo hold 12. Note that the configuration of the bulk carrier shown in the figure is merely an example and is not limited to this.

[0022] The cargo holds in which the cargo holds 12 are arranged have longitudinal structures aligned in the fore-and-aft direction. In this specification, the term "longitudinal structure" refers to a structure that is continuously arranged at the same position in the horizontal direction in the fore-and-aft direction of the cargo holds, and the longitudinal structures at the front and rear may be connected to each other or may be partitioned.

[0023] As shown in FIG. 2(A), the longitudinal structure includes, for example, topsides 12a arranged on both sides of the upper part of the cargo hold 12, hoppers 12b arranged on both sides of the lower part of the cargo hold 12, and a double bottom 12c arranged at the bottom of the cargo hold.

[0024] The topside 12a, for example, forms a tank inside which seawater can be poured and discharged, and has the function of adjusting the inclination of the hull and cargo. The hopper 12b and double bottom 12c form a ballast tank inside which seawater can be poured and discharged. Note that some bulk carriers do not have the topside 12a or hopper 12b.

[0025] Adjacent cargo holds 12 are separated into front and rear sections by a hull bulkhead 17. Each cargo hold 12 is formed of a space surrounded by a hull sidewall 18 made of outer plating, a topside 12a, a hopper 12b, and a double bottom 12c.

[0026] In the methanol-fueled ship 1 according to this embodiment, the internal space formed by the bulkhead steel plates 2, the sidewall steel plates 3, and the longitudinal structure (here, the topside 12a, hopper 12b, and double bottom 12c) is used as a fuel tank 20 that stores methanol fuel. In addition, in the methanol-fueled ship 1 according to this embodiment, the bulkhead steel plates 2, the sidewall steel plates 3, and the compartment steel plates 4 are configured to form a cofferdam 30 that surrounds the outer periphery of the fuel tank 20.

[0027] The bulkhead steel plates 2 are steel plates welded to the inner surfaces of the hull sidewalls 18 and longitudinal structures (here, the topsides 12a, hoppers 12b, and double bottoms 12c) so as to form a cofferdam 30 between the fuel tanks 20 and the hull bulkheads (bulkheads 17). The bulkhead steel plates 2 include a steel plate that forms the front surface of the fuel tanks 20 and a steel plate that forms the rear surface of the fuel tanks 20.

[0028] The sidewall steel plates 3 are steel plates welded to the inner surfaces of the bulkhead steel plates 2 and the longitudinal structure (here, the topside 12a and the hopper 12b) so as to form a cofferdam 30 between the fuel tank 20 and the hull side wall 18. The sidewall steel plates 3 include a steel plate that forms the left side surface of the fuel tank 20 and a steel plate that forms the right side surface of the fuel tank 20.

[0029] The partitioning steel plates 4 are steel plates that divide the internal space of the longitudinal structure into front and rear sections, thereby forming the cofferdam 30. Specifically, the partitioning steel plates 4 are, for example, steel plates that divide the internal space of the topside 12a into front and rear sections, steel plates that divide the internal space of the hopper 12b into front and rear sections, and steel plates that divide the double bottom 12c into front and rear sections, and may be made of the same steel plates as the hull bulkheads (bulkheads 17).

[0030] The top steel plate 5 is a steel plate welded between the front and rear bulkhead steel plates 2 and the left and right top sides 12a so as to form a cofferdam 30 between the fuel tank 20 and the upper deck 11. The top steel plate 5 can be omitted if necessary.

[0031] The methanol-fueled ship 1 according to the first embodiment has a fuel tank 20 located in the center of the hull. As shown in the figure, the fuel tank 20 is located between multiple cargo holds 12. When the fuel tank 20 is located in the center of the hull, the impact on the hull strength and bending stress can be reduced.

[0032] As shown in Figure 2(B), the cofferdam 30 formed by the bulkhead steel plate 2, sidewall steel plate 3, compartment steel plate 4, and top steel plate 5 may be configured to communicate the spaces partitioned by each steel plate. This configuration can reduce gas accumulation and reduce the equipment costs for alarm devices, etc. Note that, to communicate the cofferdams 30, openings can be formed in the steel plates as needed.

[0033] According to the methanol-fueled ship 1 according to the above-described embodiment, by arranging the bulkhead steel plates 2 and the sidewall steel plates 3 to use part of the hull structure as the fuel tank 20 and to use part of the hull structure (longitudinal structure) as the cofferdam 30, it is possible to reduce the hull weight while ensuring the capacity of the fuel tank 20.

[0034] FIG. 3 shows modified fuel tanks, with (A) showing a first modified example, (B) showing a second modified example, and (C) showing a third modified example. In the first modified example shown in FIG. 3(A), the bottom of the fuel tank 20 is configured as a single bottom 12d. That is, in the first modified example, the double bottom 12c located below the fuel tank 20 is used as the fuel tank 20. Because a cofferdam is not required below the water surface, all or part of the inner steel plate constituting the double bottom 12c can be removed. Although not shown, the lower part of the hopper 12b adjacent to the double bottom 12c may also be used as a fuel tank.

[0035] In a second modified example shown in Figure 3(B), the fuel tank 20 is formed on a hull that does not have a hopper 12b. In a third modified example shown in Figure 3(C), the fuel tank 20 is formed on a hull that does not have a topside 12a. Even if the longitudinal structure differs depending on the size of the hull, the type of cargo, etc., the fuel tank 20 and cofferdam 30 can be formed as desired by arranging the bulkhead steel plates 2, sidewall steel plates 3, and compartment steel plates 4.

[0036] Next, a methanol-fueled ship according to a second embodiment of the present invention will be described with reference to Figures 4(A) and 4(B). Figure 4 is a cross-sectional view of the methanol-fueled ship according to the second embodiment of the present invention, with (A) showing the cargo hold section and (B) showing the fuel tank section. Note that components that are the same as those in the first embodiment described above are given the same reference numerals, and duplicate descriptions will be omitted.

[0037] The methanol-fueled ship 1 according to the second embodiment is designed for a ship with a double hull (double hull structure), as shown in Figure 4(A). In this embodiment, the sections corresponding to the topside 12a, hopper 12b, and double bottom 12c shown in Figure 2(A) are constructed with a double-wall structure 19. In other words, when the ship has a double hull (double hull structure), the longitudinal structure is constructed with a double-wall structure 19, and as shown in Figure 4(B), the section of the double-wall structure 19 is used as a fuel tank 20.

[0038] Next, a methanol-fueled ship according to a third embodiment of the present invention will be described with reference to Figures 5(A) to 6(C). Figure 5 shows a methanol-fueled ship according to the third embodiment of the present invention, with (A) being a side view and (B) being a plan view of the upper deck. Figure 6 shows a cross-sectional view of the methanol-fueled ship shown in Figure 5, with (A) showing the cargo hold section, (B) showing the fuel tank section, and (C) showing a modified example. Note that components that are the same as those in the first embodiment described above are designated by the same reference numerals, and redundant explanations will be omitted.

[0039] As shown in Figures 5(A), 5(B), and 6(B), the methanol-fueled ship 1 according to the third embodiment has a fuel supply device room 21 installed on the upper deck 11 directly above the fuel tank 20. In the fuel supply device room 21, a fuel supply device that supplies methanol fuel from the fuel tank 20 to the main engine in the engine room 13 is disposed.

[0040] In the third embodiment, since there is no need to provide a cofferdam between the fuel supply device chamber 21 and the fuel tank 20, the top steel plate 5 in the first embodiment can be omitted, as shown in Fig. 6(B). Also, as shown in Fig. 5(B), it is preferable that the outer periphery of the fuel supply device chamber 21 is larger than the upper opening of the fuel tank 20 in a plan view. With this configuration, the outer periphery of the fuel tank 20 can be reliably surrounded by a cofferdam.

[0041] 6(C), in cases where the space required for installing the fuel supply device is small, the fuel supply device room 21 and the cofferdam 22 may be installed on the upper deck 11 directly above the fuel tank 20, and the auxiliary compartment room 23 may be installed in the space above the cofferdam 22. In the auxiliary compartment room 23, for example, an inert gas supply device or the like may be arranged.

[0042] Although not shown, the entire fuel supply device room 21 shown in Figure 6(B) may be configured as a cofferdam. In this case, the ceiling height can be lowered because the fuel supply device and the like are not installed inside. In this case, the fuel supply device must be installed separately on the upper deck 11, but there is no need to install a top steel plate 5 on the fuel tank 20, and the volume of the fuel tank 20 can be increased.

[0043] Next, a methanol-fueled ship according to a fourth embodiment of the present invention will be described with reference to Figures 7(A) to 9. Here, Figure 7 shows a methanol-fueled ship according to the fourth embodiment of the present invention, with (A) being a side view and (B) being a plan view of the upper deck. Figure 8 is a cross-sectional view of the methanol-fueled ship shown in Figure 7, with (A) showing the cargo hold section and (B) showing the fuel tank section. Note that the same components as those in the first embodiment described above are designated by the same reference numerals, and redundant explanations will be omitted.

[0044] 7(A) and 7(B), the methanol-fueled ship 1 according to the fourth embodiment has the fuel tank 20 located in front of the engine room 13. With this configuration, the length of the piping that supplies methanol fuel from the fuel tank 20 to the main engine in the engine room 13 can be shortened.

[0045] The bulkhead steel plate 2 that forms the front surface of the fuel tank 20 is arranged so as to have a predetermined gap with the hull bulkhead (bulkhead 17) that forms the aft-most cargo hold 12. The bulkhead steel plate 2 that forms the aft surface of the fuel tank 20 is arranged so as to have a predetermined gap with the front hull bulkhead that defines the engine room 13.

[0046] 9 is a schematic diagram showing a modified example of the methanol-fueled ship according to the fourth embodiment. In the modified example shown in the figure, the fuel tank 20 is located in front of the engine room 13, and a fuel supply device room 21 is installed on the upper deck 11 directly above the cofferdam 30 formed between the fuel tank 20 and the engine room 13.

[0047] The fuel supply device room 21 contains devices necessary for fuel supply, such as a fuel supply device 80, a service tank 81, and a fuel valve train 82. A pump 83 that sucks out methanol fuel is installed in the fuel tank 20. The methanol fuel sucked out by the pump 83 is temporarily stored in the service tank 81.

[0048] A main engine 84 driven by methanol fuel is installed in the engine room 13, and the methanol fuel is supplied to the main engine 84 from a fuel supply device 80 via a fuel supply pipe 85. A fuel valve train 82 is disposed midway along the fuel supply pipe 85. The fuel valve train 82 is a valve system that controls the amount of methanol fuel supplied.

[0049] The methanol-fueled ship 1 according to the fourth embodiment has a cofferdam 30 between the fuel tank 20 and the engine room 13, and by locating the fuel supply device room 21 directly above the fuel tank 20 and the cofferdam 30, a fuel supply pipe 85 can be laid from the fuel supply device room 21 through the cofferdam 30 to the main engine 84 in the engine room 13.

[0050] When laying the fuel supply piping 85 in a compartment or exposed area where crew members may enter, such as the engine room 13, the fuel supply piping 85 needs to have a double-pipe structure (including a duct structure through which the fuel supply piping 85 passes), but by routing the fuel supply piping 85 from the fuel supply device room 21 through the cofferdam 30, the length requiring the double-pipe structure can be shortened, thereby enabling a reduction in the weight of the ship. As shown in the figure, in this embodiment, the double-pipe structure 86 is formed only in the section where the piping is laid inside the engine room 13.

[0051] 9, the fuel tank 20 is disposed in front of the engine room 13, but the fuel tank 20 may be disposed in the center of the hull. In this case, too, the fuel supply pipe 85 is routed from the fuel supply device room 12 through the cofferdam 30, thereby shortening the required length of the double pipe structure and reducing the weight of the hull.

[0052] Furthermore, although not shown, in the above-described third and fourth embodiments (including their respective modified examples), if the hull of the methanol-fueled ship 1 has a double hull (double hull structure) as in the second embodiment shown in FIG. 4 , the double-hull double-wall structure can be used as the fuel tank 20.

[0053] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0054] 1 Methanol fuel ship, 2 Bulkhead steel plate, 3 Sidewall steel plate, 4 Compartment steel plate, 5 Top steel plate, 11 Upper deck, 12 Cargo hold, 12a Topside (longitudinal structure), 12b Hopper (longitudinal structure), 12c Double bottom (longitudinal structure), 12d Single bottom, 13 Engine room, 14 Accommodation space, 15 Deck crane, 16 Hatch cover, 17 Bulkhead (hull bulkhead), 18 Hull sidewall, 19 Double wall structure (longitudinal structure), 20 Fuel tank, 21 Fuel supply equipment room, 22, 30 Cofferdam, 23 Auxiliary compartment, 80 Fuel supply equipment, 81 Service tank, 82 Fuel valve train, 83 Pump, 84 Main engine, 85 Fuel supply piping, 86 Double pipe structure

Claims

1. A methanol-fueled ship having a hull that can be propelled by methanol fuel, comprising: a pair of bulkhead steel plates arranged to form a specified gap with a hull bulkhead; a pair of sidewall steel plates arranged to form a specified gap with the hull sidewall; and partition steel plates which divide a part of the hull's longitudinal structure into front and rear parts, wherein an internal space formed by the bulkhead steel plates, the sidewall steel plates and the longitudinal structure is used as a fuel tank, and the bulkhead steel plates, the sidewall steel plates and the partition steel plates are configured to form a cofferdam that surrounds the outer periphery of the fuel tank.

2. The methanol-fueled ship according to claim 1, wherein the longitudinal structure is a hopper of a cargo hold, a topside of a cargo hold, a double bottom or a double-hull double-wall structure.

3. A methanol-fueled ship as described in claim 1, comprising a top steel plate arranged to form a predetermined gap with the upper deck.

4. A methanol-fueled ship according to claim 2, wherein the hopper, the double bottom or the double wall structure located below the fuel tank is utilized as the fuel tank.

5. A methanol-fueled ship as described in claim 1, wherein the fuel tank is located in the center of the hull or in front of the engine room.

6. A methanol-fueled ship as described in claim 1, comprising a cofferdam or fuel supply equipment room located on the upper deck directly above the fuel tank.

7. A methanol-fueled ship as described in claim 1, further comprising a fuel supply equipment room located on the upper deck directly above the fuel tank and the cofferdam, and a fuel supply piping for supplying carbon recycled fuel from the fuel tank to the main engine is configured to pass through the fuel supply equipment room and the cofferdam.

8. The methanol-fueled vessel of claim 1, wherein the methanol-fueled vessel is a bulk carrier.

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