JP7749478B2 - cargo ship - Google Patents

Description

The present invention relates to a cargo ship for transporting cargo.

Cargo ships that transport cargo are generally known. For example, a bulk carrier that reduces carbon dioxide emissions by improving cargo handling efficiency has been disclosed (see Patent Document 1). Furthermore, many cargo ships use fossil fuels as fuel.

JP 2013-180692 A

However, from the perspective of reducing carbon dioxide emissions, which are of concern due to their impact on the global environment, there is a demand for cargo ships that use fuels other than fossil fuels.
An object of an embodiment of the present invention is to provide a cargo ship that uses fuel such as ethanol.

A cargo ship according to an aspect of the present invention comprises multiple cargo holds for loading cargo, a structure provided on the deck at the bow of the hull and equipped with living quarters, a propulsion device provided at the stern of the hull and consisting of pod thrusters, a single-hull fuel tank arranged on the outside in the width direction of the hull and storing ethanol or methanol as fuel for the propulsion device, and a pump for taking in water from outside the ship.

According to an embodiment of the present invention, a cargo ship that uses ethanol or other fuels can be provided.

1 is a side view showing the configuration of a cargo ship according to a first embodiment of the present invention. FIG. 2 is a top view showing the internal configuration of the hull according to the first embodiment. FIG. 1 is a structural diagram showing a cargo hold portion of a cargo ship according to a first embodiment. 1 is a simplified diagram showing the configuration of an electrohydraulic pump according to a first embodiment; FIG. 1 is a simplified diagram showing the configuration of an electric pump according to a first embodiment. FIG. 2 is a diagram showing the internal configuration of a pump space according to the first embodiment. FIG. 10 is a side view showing the configuration of a cargo ship according to a second embodiment of the present invention. FIG. 10 is a top view showing the internal configuration of the hull according to the second embodiment. FIG. 10 is a side view showing the configuration of a cargo ship according to a third embodiment of the present invention. FIG. 11 is a top view showing the internal configuration of a hull according to a third preferred embodiment of the present invention.

(First embodiment)
Fig. 1 is a side view showing the configuration of a cargo ship 1 according to a first embodiment of the present invention. Fig. 2 is a top view showing the internal configuration of a hull 2 according to this embodiment. The dotted line in Fig. 2 represents the shape of the bottom of the ship. Fig. 3 is a configuration diagram showing a cargo hold 11 of the cargo ship 1 according to this embodiment. Note that identical parts in the drawings are given the same reference numerals, and duplicate explanations will be omitted where appropriate.

Cargo ship 1 is a ship that carries cargo. Cargo ship 1 may be a bulk carrier or a tanker, but may be a ship that carries any type of cargo. For example, cargo ship 1 may be a car carrier or a container ship. Here, cargo ship 1 will be described primarily as a ship type that adopts the layout of a bulk carrier or a tanker.

Cargo ship 1 is a ship that uses ethanol as fuel. The fuel is not limited to high-purity ethanol, and may be bioethanol produced from plants. Furthermore, methanol may be used as fuel instead of ethanol. The following description will be given assuming that the fuel is ethanol. Furthermore, while it is desirable for cargo ship 1 not to use fossil fuels, fossil fuels may be used in part. For example, fossil fuels may be used for equipment (auxiliary machinery, etc.) other than the main engine used to generate propulsion power. Here, cargo ship 1 is described as a ship that navigates the ocean, but it may also be a ship that navigates rivers or lakes.

The cargo ship 1 comprises a hull 2, a bridge 3, a propulsion unit 4, a generator 5, two liquefaction units 6, and multiple pumps 7. The hull 2 includes multiple cargo holds 11, two fuel tanks 12, an engine room 13, multiple ballast tanks 14, and two pump spaces 15.

The bridge 3 is located on the deck at the bow of the cargo ship 1. The bridge 3 is a structure that includes living quarters for the crew. The bridge 3 is located so that it is not directly above the cargo holds 11. Because the bridge 3 is located at the bow, it may be smaller than a typical bridge located at the stern of a ship. By placing the bridge 3 at the bow, forward visibility is improved, more space can be provided on the deck at the stern to install equipment, and the cargo space can be raised.

Here, the bow portion may be the portion located on the bow side of the compartment in which the cargo holds 11 are located, or the portion located on the bow-most side of the cargo ship 1 when the longitudinal direction of the cargo ship 1 is divided into thirds, or any other portion that would be recognized as the bow portion by a person skilled in the art. Similarly, the stern portion may be the portion located on the stern side of the compartment in which the cargo holds 11 are located, or the portion located on the stern-most side of the cargo ship 1 when the longitudinal direction of the cargo ship 1 is divided into thirds, or any other portion that would be recognized as the stern portion by a person skilled in the art.

The propulsion unit 4 is mounted on the lower part of the stern of the hull 2. The propulsion unit 4 is a pod propulsion unit. The pod propulsion unit is pod-shaped (cocoon-like) and has a propeller attached to it. The propeller is rotated by a motor built into the pod propulsion unit, thereby generating propulsion force for the cargo ship 1. The pod propulsion unit rotates horizontally relative to the hull 2, thereby changing the direction of travel of the cargo ship 1 in any direction. Therefore, the pod propulsion unit acts as a rudder, eliminating the need for a rudder. Furthermore, by using a pod propulsion unit as the propulsion unit 4, the engine room 13 can be made smaller than in ships that use heavy oil-fired engines to generate propulsion force.

The propulsion device 4 may be a single-screw vessel employing single-screw pod propulsion with one pod propeller, or a twin-screw vessel employing twin-screw pod propulsion with two pod propellers. By employing twin-screw pod propulsion, the main engine can be duplicated, ensuring the safe navigation of the cargo ship 1. Furthermore, by making the cargo ship 1 a twin-screw vessel, the stern of the cargo ship 1 is wider than that of a single-screw vessel, allowing for more space to be installed for equipment in the stern.

The generator 5 is mounted on the deck at the stern of the hull 2. The generator 5 is a generator that uses ethanol as fuel. The generator 5 supplies the generated electricity to the propulsion unit 4. In other words, the generator 5 is the power source for the propulsion unit 4. The generator 5 may also supply power to devices other than the propulsion unit 4. For example, the generator 5 is a diesel generator, but any generator that uses ethanol as fuel may be used.

The liquefaction device 6 is installed above the fuel tank 12 or cargo hold 11. The liquefaction device 6 cools and re-liquefies the vaporized ethanol stored in the fuel tank 12 using fresh water or seawater. Re-liquefying the vaporized ethanol inside the fuel tank 12 prevents the internal pressure of the fuel tank 12 from increasing excessively, and prevents the ethanol gas from escaping into the atmosphere. Note that this is not limited to the liquefaction device 6, and any other device may be installed as long as it can prevent the internal pressure of the fuel tank 12 from becoming excessive. For example, instead of the liquefaction device 6, a safety valve may be installed that acts as a vent to release vaporized ethanol inside the fuel tank 12 to the outside.

The pumps 7 are provided in the pump spaces 15 on the bow and stern sides adjacent to the cargo holds 11. The pumps 7 may also be provided in the fuel tanks 12. All of the pumps 7 may be provided in either the pump spaces 15 on the bow or stern sides. The pumps 7 are equipment for taking in seawater (natural water) from outside the ship for use on board. The pumps 7 are generally rod-shaped and vertically extend, sucking up water vertically from the bottom of the ship. The pumps 7 function as vertical piping through which the sucked up water flows. Therefore, the pumps 7 can be installed in narrow spaces horizontally (e.g., the length of the cargo ship 1 or the width direction perpendicular to the length) as long as there is enough space to extend vertically from the bottom of the ship to the deck. For example, the pumps 7 may be submerged pumps (deepwell or submerged pumps, etc.) in which the drive parts (impeller, etc.) are submerged. Any pump can be used as long as it can be installed in a limited space such as the pump spaces 15. Therefore, a submersible pump may be provided along with a floor-standing pump.

For example, the water (seawater) taken in by pump 7 is used as follows: First, it is used as cooling water to cool various equipment such as the generator 5. Second, it is constantly circulated through pipes laid throughout the entire ship and used as water for fire extinguishing. Third, it is used as water to store in ballast tanks 14. Note that each pump 7 may be used for one or more of the above three purposes, or for a purpose other than the above three purposes.

Two example configurations of the pump 7 will be described with reference to Figures 4 and 5. Note that the configurations described here have been simplified for ease of explanation and may not strictly match the configuration of the actual pump.

FIG. 4 is a simplified diagram showing the configuration of an electric hydraulic pump 7a according to this embodiment.
The pump 7a includes a control unit 71a, a motor 72a, an impeller 73a, and piping 74a. The control unit 71a is provided on the upper part of the pump 7a. The motor 72a and the impeller 73a are provided on the lower part of the pump 7a and are submerged in water when in use.

The motor 72a is a hydraulic motor. The control unit 71a controls the motor 72a hydraulically. When the motor 72a is driven, the impeller 73a connected to the rotating shaft of the motor 72a rotates. Water is sucked up by the rotation of the impeller 73a and discharged from the top of the pump 7a (e.g., above the deck) through the pipe 74a.

FIG. 5 is a simplified diagram showing the configuration of an electric pump 7b according to this embodiment.
The pump 7b includes a control unit 71b, a motor 72b, an impeller 73b, and piping 74b. The control unit 71b may not be part of the pump 7b, but may be a separate device from the pump 7b. The motor 72b is provided on the upper part of the pump 7b. The impeller 73b is provided on the lower part of the pump 7b and is submerged in water when in use.

Motor 72b is an electric motor. Control unit 71b controls motor 72b. When motor 72b is driven, impeller 73b connected to the rotating shaft of motor 72b rotates. Water is sucked up by the rotation of impeller 73b and discharged from the top of pump 7b (e.g., above the deck) through pipe 74b.

As shown in Figures 4 and 5, by using a pump with a long axis that extends vertically, the piping space for the pump 7 inside the hull 2 can be eliminated, and the size of the pump space 15 can be reduced.

The cargo holds 11 serve as containers for loading cargo to be transported by the cargo ship 1. The cargo holds 11 may also be tanks. The compartment in which the cargo holds 11 are located occupies most of the cargo ship 1, centered around the longitudinal center of the cargo ship 1. The cargo stored in the cargo holds 11 may be gas, liquid, or solid. The cargo ship 1 can increase its cargo carrying capacity by increasing the total capacity of all cargo holds 11.

The fuel tanks 12 are located at the outermost positions in the width direction of the hull 2 of the cargo ship 1, and are provided on both sides of the compartment in which the cargo holds 11 are located. Specifically, a fuel tank 12 is provided on the outside of each of the two cargo holds 11 located furthest aft. The fuel tanks 12 have a single-hull structure. The fuel tanks 12 are tanks that store ethanol, the fuel for the cargo ship 1. Here, the fuel stored in the fuel tanks 12 is ethanol. Even if ethanol leaks into the ocean, it has little impact on the environment. Therefore, the fuel tanks 12 can have a single-hull structure. Note that in order to increase the loading capacity of the fuel tanks 12, for reasons such as ensuring cruising range, an additional compartment in which the fuel tanks 12 are located may be added to part of the compartment in which the cargo holds 11 are located or to the ballast tank 14.

The engine room 13 is a room where equipment related to the navigation of the cargo ship 1 is installed. For example, the engine room 13 is equipped with equipment for operating or controlling the propulsion unit 4.

As shown in Figure 3, ballast tanks 14 are provided on both sides and at the bottom of the ship, surrounding the cargo hold 11. Therefore, the cargo hold 11 has a double-hull structure with the ballast tanks 14 provided on the outside. The ballast tanks 14 are tanks that store water (ballast water) inside and control the attitude of the cargo ship 1.

The pump spaces 15 are provided on the bow and stern sides, adjacent to the compartments where the cargo holds 11 are located. Specifically, the bow-side pump space 15 is provided adjacent to the bow side of the cargo hold 11 located furthest to the bow. The stern-side pump space 15 is provided adjacent to the stern side of the cargo hold 11 located furthest to the stern. For example, the pump space 15 may be a cofferdam provided between the compartments where the cargo holds 11 are located and other compartments on the tanker. Therefore, the pump space 15 may be provided anywhere, as long as it is provided adjacent to the compartments where the cargo holds 11 are located.

The pump space 15 can be a narrow horizontal space, as long as there is enough space extending vertically from the bottom of the ship to the deck. In other words, the pump space 15 can be located anywhere as long as a vertically extending pump 7 can be installed. Therefore, by using dead space with little utility value in the hull 2 as the pump space 15, the limited space in the hull 2 can be used effectively. For example, by making the cargo ship 1 a twin-screw ship, the space on the stern side of the hull 2 will be larger than in a single-screw ship. This makes it easier to secure the pump space 15 on the stern side of the hull 2.

Referring to Figure 6, the internal configuration of the pump space 15 on the stern side will be explained. The pump space 15 on the bow side has the same configuration as the pump space 15 on the stern side, except that there are no fuel tanks 12 located on either side.

Fuel tanks 12 are located on both sides of the pump space 15 on the stern side. A simple cavity may be provided instead of the fuel tanks 12. A high sea chest (intake) 31 is provided at the bottom of the port (or starboard) side of the pump space 15 to pass through the fuel tank 12 and take in water (e.g., seawater) from the outside (e.g., the sea). In addition, another low sea chest 31 is provided at the bottom of the pump space 15.

When water is to be taken into the ship, either the high sea chest 31 or the low sea chest 31 is opened. Normally, the low sea chest 31 located on the bottom of the ship is opened. If the cargo ship 1 is in shallow waters, opening the sea chest 31 located on the bottom of the ship could result in mud and other debris being taken into the ship along with the water. In such cases, the high sea chest 31 located on the side of the hull 2 is opened.

Water taken into the pump space 15 from the sea chest 31 is filtered by the strainer 33, which removes debris and other contaminants from the water. The filtered water is then pumped into the bottom of the ship where the pump 7 is installed. The pump 7 then pumps the filtered water up to the deck 32, located above the pump space 15. The water pumped up by the pump 7 passes through a piping network installed on the deck and is supplied to various locations on the ship (such as the ballast tank 14) for various purposes.

According to this embodiment, it is possible to provide an ethanol-fueled cargo ship 1 that has the same output and maximum cargo capacity as a cargo ship of the same size that uses heavy oil as fuel.

Here, a cargo ship 1 that uses ethanol as fuel requires approximately twice the amount of fuel to achieve the same output as a cargo ship that uses heavy oil as fuel. Therefore, the fuel tank 12 needs to have approximately twice the capacity of a fuel tank that uses heavy oil as fuel.

By installing the bridge 3 at the bow, new space is secured on the deck at the stern. This allows the generator 5 and other equipment to be installed on the deck. By using pod thrusters as the cargo ship 1's propulsion device 4, the size of the engine room located at the stern is reduced. By using a single-hull structure for the fuel tank 12, installation space is reduced compared to a double-hull structure. This allows the fuel tanks 12 to be located on both sides of the cargo hold 11. In this way, the capacity of the fuel tanks 12 can be increased while still securing a compartment for the cargo hold 11.

In addition, by using a pump (e.g., a submersible pump) that is rod-shaped and extends vertically overall as the pump 7 for taking in water, and that functions as a vertically extending pipe through which the sucked up water flows, the pump space 15 in which the pump 7 is installed can be made smaller than a pump room in which a floor-mounted pump is installed.

Second Embodiment
Fig. 7 is a side view showing the configuration of a cargo ship 1A according to a second embodiment of the present invention. Fig. 8 is a top view showing the internal configuration of a hull 2A according to this embodiment. The dotted line in Fig. 8 represents the shape of the ship bottom.

The cargo ship 1A is similar to the cargo ship 1 of the first embodiment, except that instead of the hull 2, a hull 2A is provided in which the pump spaces 15 are combined into one and repositioned.

The pump space 15 is provided in the compartment where the cargo holds 11 are located. Specifically, the pump space 15 is provided between the cargo hold 11 located furthest aft and the cargo hold 11 adjacent to this cargo hold 11 on the bow side. The pump space 15 may be provided anywhere in the compartment where cargo holds 11 are located. For example, by providing a pump space 15 between two adjacent cargo holds 11, it may also serve as a partition separating the two cargo holds 11.

The cofferdam 16 is a space provided between the compartment in which the cargo hold 11 is located and other compartments. The cofferdam 16 is provided depending on the type of cargo hold 11, but it does not have to be provided. Optional equipment may also be installed in the cofferdam 16.

In addition to the advantageous effects of the first embodiment, this embodiment ensures that each pump space 15 is larger than the pump space 15 in the first embodiment.

The cargo ship 1A is shaped so that its bow and stern sides are narrower than its longitudinal center section. To increase cargo carrying capacity, the compartments where the cargo holds 11 are located are located in the central section where the cargo holds 11 are wider. For this reason, if pump spaces 15 are located on the bow and stern sides, it is difficult to ensure that the pump spaces 15 are wide, especially in the width direction, and the number of pumps 7 that can be installed in each pump space 15 is reduced. Therefore, by providing pump spaces 15 in the compartments where the cargo holds 11 are located, the number of pumps 7 that can be installed in each pump space 15 can be increased.

Furthermore, the pump space 15 may be located anywhere in the compartment in which the cargo holds 11 are located. For example, the pump space 15 can be located between two adjacent cargo holds 11, with little impact on the layout of the cargo holds 11. This allows the cargo holds 11 to be arranged arbitrarily without having to consider the position of the pump space 15. Although one pump space 15 is preferable, two or more may be provided.

(Third embodiment)
Fig. 9 is a side view showing the configuration of a cargo ship 1B according to a third embodiment of the present invention. Fig. 10 is a top view showing the internal configuration of a hull 2B according to this embodiment. The dotted line in Fig. 10 represents the shape of the ship bottom.

The cargo ship 1B is the cargo ship 1 of the first embodiment, except that the hull 2A is provided instead of the hull 2. The hull 2A is the hull 2 of the first embodiment, except that the pump room 17 in which the pump 7B is installed is provided instead of the pump space 15 in which the pump 7 is installed. In all other respects, it is the same as the first embodiment.

The pump room 17 is located under the bottom of a portion of the cargo hold 11B located furthest aft. A pump 7B is installed in the pump room 17. For example, the pump 7B is a floor-mounted type. However, any type of pump 7B may be used.

The bottom surface of cargo hold 11B, located above pump chamber 17, has a section below which pump chamber 17 is located and a section below which pump chamber 17 is not located. The bottom surface where pump chamber 17 is located is higher than the bottom surface where pump chamber 17 is not located. The bottom surface where pump chamber 17 is located has a slope SL so that the side of the bottom surface where pump chamber 17 is not located is lower.

By providing an inclined SL, gravity acts to move cargo loaded on the bottom surface where the pump chamber 17 is located toward the bottom surface where the pump chamber 17 is not located. As a result, if the cargo is liquid or powdery, when the amount of cargo in cargo hold 11B decreases, all of the cargo will accumulate on the bottom surface where the pump chamber 17 is not located. This makes it easier to remove all of the cargo stored in cargo hold 11B without leaving any behind.

This embodiment provides the same effects as the first embodiment. Furthermore, by providing a pump chamber 17 instead of the pump space 15 of the first embodiment, a floor-mounted pump 7B can be provided. This allows for the use of a pump 7B of a different type than the pump 7 of the first embodiment.

Additional advantages and modifications may readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

1...Cargo ship, 2...Hull, 3...Bridge, 4...Propulsion unit, 5...Generator, 6...Liquefaction unit, 7...Pump, 11...Cargo hold, 12...Fuel tank, 13...Engine room, 14...Ballast tank, 15...Pump space.

Claims (10)

a plurality of cargo holds for loading cargo;
A structure provided on the deck of the bow portion of the hull and equipped with a living area;
a propulsion device provided at the stern of the hull and configured with pod propulsors;
A fuel tank arranged on the outer side of the hull in the width direction, storing ethanol or methanol as fuel for the propulsion device, and configured as a single hull;
A cargo ship characterized by being equipped with a pump that takes in water from outside the ship. 2. The cargo ship according to claim 1, wherein the pump has a rod shape extending generally vertically and functions as a vertically extending pipe through which the pumped water flows. 3. The cargo ship according to claim 2, wherein the pump is provided in a pump space adjacent to the cargo hold. 3. The cargo ship according to claim 2, wherein the pump is provided in a pump space adjacent to a compartment in which the cargo hold is provided. 3. The cargo ship according to claim 2, wherein the pump is provided in a pump space provided in a compartment in which the cargo hold is provided. 3. The cargo ship according to claim 2, wherein the pump is provided in a pump space provided between two adjacent cargo holds. 2. The cargo ship according to claim 1, wherein the pump is provided in a pump room located under the cargo hold and is a floor-mounted pump. 2. The cargo ship according to claim 1, wherein the propulsion device comprises two pod thrusters. 2. The cargo ship according to claim 1, further comprising a generator that generates electricity using ethanol or methanol stored in the fuel tank as fuel and supplies the electricity to the propulsion device. 10. The cargo ship according to claim 9, wherein the generator is provided on the deck of the stern portion of the hull.