JPH10167189A - Electric proplusive type methanol tanker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide efficient electric propulsion by rotating a propeller by electric power generated in a fuel cell by separating hydrogen from mixed gas after reforming methanol to the mixed gas of hydrogen and carbon dioxide and by chemical reaction of this hydrogen and oxygen from a tank for oxygen storage. SOLUTION: A tank 1 for methanol storage, a tank 2 for oxygen storage and a reformer 4 to reform methanol taken out of the tank 1 for methanol storage to mixed gas of hydrogen and carbon dioxide are provided in a hull 14. A hydrogen separator 5 to separate hydrogen from the mixed gas generated in the reformer 4 is provided, and a fuel cell 3 to generate a direct electric current by receiving hydrogen fed and supplied from this separator 5 and oxygen fed and supplied from the tank 2 for oxygen storage through an oxygen supplier 8 is provided. Thereafter, propulsive force is provided by connecting an electric motor 6 for propeller driving to an electric power regulator 7 fed electricity from the fuel cell 3 and rotating a propeller 17 by motive power generated by the electric motor 6 through a reducing gear 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vessel for transporting methanol, and more particularly to a methanol transport vessel capable of generating electric power by utilizing methanol for electric propulsion.

[0002]

2. Description of the Related Art Conventionally, a propulsion type of a ship for transporting a liquid fuel such as methanol, as represented by an oil tanker shown in FIG. 3, uses heavy oil supplied from a heavy oil tank 28 in the hull 14 as fuel. In general, a propulsion system that obtains power from a diesel engine 26 is used. However, as shown in FIG. 4, a liquid fuel, for example, methanol obtained from a liquid fuel tank 29 is vaporized and directly supplied to a spark ignition engine 27. A form of propulsion that obtains power is also conceivable. The power obtained from the diesel engine 26 or the spark ignition engine 27 is directly transmitted to the propeller shaft 16 or the reduction gear
The propeller shaft 16 is transmitted to the propeller shaft 16 via 15 to thereby rotate the propeller 17.

[0003]

When methanol is transported by a propulsion type ship powered by a diesel engine 26 shown in FIG. 3, the methanol contained in the liquid fuel tank 29 has a boiling point of about 65 ° C. For this reason, the liquid fuel is normally in a liquid state, but the pressure in the liquid fuel tank 29 increases due to the vaporization of part of the methanol during transportation.
Normally, since the pressure increase in the liquid fuel tank 29 is dangerous, a part of the vaporized gas is released to the atmosphere to prevent the pressure increase in the liquid fuel tank 29, but methanol is toxic. Therefore, it must be released to the atmosphere after some treatment to make it non-toxic. For this reason, equipment for methanol treatment is required, and the economic efficiency deteriorates.

[0004] Further, release of methanol after treatment into the atmosphere means that a part of the methanol is discarded, which increases the cost of transporting methanol. For this reason, it is economically necessary to effectively use the released methanol. A ship adopting a propulsion system that obtains power using an internal combustion engine using methanol as shown in FIG. 4 instead of releasing methanol into the atmosphere can be considered, but a spark ignition engine is used for an internal combustion engine using methanol as a fuel. 27 is used. However, since the spark ignition engine 27 is generally less efficient and has a higher rotation speed than the diesel engine 26, the spark ignition engine 27 has a propulsion type of high efficiency and low rotation (low rotation in consideration of propeller efficiency) as a propulsion type of a ship. Not. On the other hand, methanol is not suitable for the fuel of the diesel engine 26.

Although a marine gas turbine may be used instead of the spark ignition engine 27, the fuel economy of the diesel engine 26 is far less. In addition, in all of the diesel engine 26, the spark ignition engine 27, and the marine gas turbine, the exhaust gas contains nitrogen oxides, and a device for reducing nitrogen oxides is required to prevent air pollution. .

Accordingly, an object of the present invention is to provide an electric propulsion-type methanol transport ship capable of efficiently generating electric power by using a fuel cell by utilizing hydrogen gas obtained by reforming methanol and efficiently performing electric propulsion. And

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an electric propulsion type methanol transport ship according to the present invention is provided in a ship provided with a methanol storage tank for transporting methanol therein. And a reformer for reforming the methanol taken out of the methanol storage tank into a mixed gas of hydrogen and carbon dioxide, a hydrogen separator for separating hydrogen from the mixed gas, and a hydrogen separator. A fuel cell for generating a direct current by a chemical reaction between hydrogen and oxygen from the oxygen storage tank,
An electric motor that operates with the fuel cell as a power source and rotates a propeller is provided.

In the above-mentioned electric propulsion type methanol transport ship of the present invention, since methanol in the methanol storage tank is directly used as fuel, there is no need to discharge methanol into the atmosphere, which is economically advantageous.

In addition, methanol obtained by reforming methanol in a reformer and passing through a hydrogen separator generates a direct current by a fuel cell utilizing a chemical reaction with oxygen. Since it is used in an apparatus, nitrogen oxides that are a problem in air pollution are not generated. Since the chemical energy of hydrogen and oxygen is directly converted into electric energy by the fuel cell, the power generation efficiency is high, which is economically advantageous. Furthermore, since the propeller is configured to be rotationally driven by the electric motor, it is possible to reduce the rotation, which is advantageous in terms of the propeller efficiency.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic longitudinal sectional view of an electric propulsion type methanol transport ship according to an embodiment of the present invention. FIG. It is a system diagram of equipment.

As shown in FIGS. 1 and 2, this methanol transport ship has methanol (CH ₃ O) inside a hull 14.
In addition to a tank 1 for storing H), an oxygen storage tank 2 and a reformer 4 for reforming methanol taken out from the methanol storage tank 1 into a mixed gas of hydrogen and carbon dioxide are provided. Is provided.

Further, a hydrogen separator 5 for separating hydrogen from the mixed gas generated in the reformer 4 is provided, and the hydrogen supplied from the hydrogen separator 5 and the oxygen storage tank 2 are provided.
A fuel cell 3 is provided, which receives oxygen supplied from the oxygen supply device 8 via an oxygen supply device 8 to generate a DC current.

Water generated by the reaction between hydrogen and oxygen in the fuel cell 3 is led to a water tank 30, which is connected to the reformer 4.

The fuel cell 3 includes an anode 11, a cathode 12, and an electrolyte 13. An electric motor 6 for driving a propeller is provided on a power controller (or an inverter) 7 which is supplied with power via the electrodes 11, 12 or the wiring 23. It is connected. That is, the electric motor 6 is driven by the propeller via the reduction gear 15 and the propeller shaft 16.
17 is rotationally driven. 1 and 2, reference numeral 9 indicates a pipe, and reference numeral 10 indicates a methanol vaporizer and a safety valve.

The methanol in the liquid state stored in the methanol storage tank 1 is vaporized by the methanol vaporizer and the safety valve 10, passes through the pipe 9, and passes through the reformer 4.
It is led to. In the reformer 4, methanol (CH
₃ OH) by the action of copper-based catalysts
The chemical reactions shown in the formulas [1], [2] and [3] occur, and finally hydrogen (H ₂ ) and carbon dioxide (C
O ₂ ). Carbon (C) in methanol becomes carbon monoxide (CO) and carbon dioxide, but carbon monoxide is
The reaction of the formula gives carbon dioxide and hydrogen. Water (H ₂ O)
Is supplied from the water tank 30.

Embedded image CH ₃ OH → CO + 2H ₂ (decomposition reaction)

Embedded image CO + H ₂ O → CO ₂ + H ₂ O (liquid-gas phase change reaction)

Embedded image CH ₃ OH + H ₂ O → CO ₂ + 3H ₂ (reforming reaction)

The gas mixture of hydrogen and carbon dioxide coming out of the reformer 4 is led to a hydrogen separator 5 and then separated into hydrogen and carbon dioxide, and the hydrogen is led to a cathode 12 of the fuel cell 3. . Then, the carbon dioxide is discharged out of the ship by being released into the atmosphere or dissolved in seawater.

In the oxygen storage tank 2, oxygen is usually stored in a liquid form. This oxygen is led to the oxygen supplier 8, vaporized, and then led to the anode 11 of the fuel cell 3.
In the fuel cell 3, when the reaction of the formula [4] takes place, the anode
The movement of ions occurs through the electrolyte 13 sandwiched between the cathode 11 and the cathode 12, and electric power is generated.

Embedded image H ₂ + (1/2) O ₂ → H ₂ O

The anode 11 and the cathode 12 are made of porous carbon or the like, and the electrolyte 13 is made of a polymer polymer, phosphoric acid, an aqueous alkali solution, stabilized zirconia, or the like. Water 22 generated by the reaction in the fuel cell 3 is guided to a water tank 30 and reused as water to be supplied to the reformer 4.

The direct current generated by the fuel cell 3 is connected to a wiring
It is led to the power controller (or inverter) 7 through 23. When the electric motor 6 is a DC motor, the power controller 7 adjusts the output voltage or output current to the motor.
When the electric motor 6 is an AC motor, an inverter is attached to the power controller 7 and converts DC current from the fuel cell 3 into AC current. After that, the output voltage or the output current is adjusted by the power controller 7 and used as the power of the electric motor 6.

The power generated by the electric motor 6 is transmitted directly to the propeller shaft 16 or transmitted to the propeller shaft 16 via the reduction gear 15 to rotate the propeller 17.

In the above-described embodiment, since methanol in the methanol storage tank 1 is directly used as fuel, there is no need to release methanol into the atmosphere, which is economically excellent. Further, since methanol is reformed into hydrogen in the reformer 4 and a direct current is generated by the fuel cell 3 utilizing a chemical reaction between the hydrogen and oxygen, the electric power is used as the electric power for the propulsion motor 6.
Nitrogen oxides that are a problem in air pollution are not generated. Therefore, there is no need for a device for reducing nitrogen oxides, which is economically excellent. Further, since sulfur components are not contained in methanol, sulfur oxides that are a problem in air pollution are not generated, and it is not necessary to provide a device for removing sulfur oxides.

Further, since chemical energy of hydrogen and oxygen is directly converted into electric energy by the fuel cell 3,
It has high power generation efficiency and is economically excellent. Further, since the propeller 17 is rotated by the electric motor 6 to generate a thrust, the rotation of the propeller 17 can be reduced, which is advantageous in terms of efficiency. The use of the electric motor 6 makes it possible to provide a ship having lower vibration and lower noise than the diesel engine 26 and the spark ignition engine 27. Further, since the volume of oxygen to be stored can be reduced by liquid oxygen, the size of the oxygen storage tank 2 can be reduced. Since methanol is in a liquid state at normal temperature, the methanol storage tank 1 does not require any special heat insulating material or safety device, and is economically excellent.

[0023]

As described in detail above, the electric propulsion type methanol transport ship of the present invention has the following effects. (1) Since methanol in the methanol storage tank is used directly as fuel, there is no need to release methanol into the atmosphere, which is economically superior. (2) Methanol is reformed into hydrogen in a reformer, and a direct current is generated by a fuel cell utilizing the chemical reaction between the hydrogen and oxygen, which is used as power for the propulsion motor. No oxides are generated. Therefore, there is no need for a device for reducing nitrogen oxides, which is economically excellent. (3) Since methanol does not contain a sulfur component, sulfur oxides, which pose a problem in air pollution, are not generated, and there is no need to provide a device for removing sulfur oxides. (4) Since the chemical energy of hydrogen and oxygen is directly converted into electric energy by the fuel cell, the power generation efficiency is high,
Excellent financially. (5) Since the thrust is generated by rotating the propeller by the electric motor, it is possible to reduce the rotation, which is advantageous for the propeller efficiency. (6) By using an electric motor, a ship with lower vibration and lower noise can be provided as compared with a diesel engine or a spark ignition engine. (7) Since the volume of oxygen to be stored can be reduced by liquid oxygen, the size of the oxygen storage tank can be reduced. (8) Since methanol is in a liquid state at room temperature, the methanol storage tank does not require special heat insulating materials or safety devices, and is economically excellent.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view schematically showing an electric propulsion type methanol transport ship as one embodiment of the present invention.

FIG. 2 is a system diagram showing an electric propulsion facility of the ship of FIG.

FIG. 3 is a longitudinal sectional view of a conventional liquid fuel transport ship having a propulsion type using heavy oil as fuel.

FIG. 4 is a longitudinal sectional view of a conventional liquid fuel transport ship having a propulsion type using methanol as a fuel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Methanol storage tank 2 Oxygen storage tank 3 Fuel cell 4 Reformer 5 Hydrogen separator 6 Electric motor 7 Power controller or inverter 8 Oxygen supply 9 Piping 10 Methanol vaporizer and safety valve 11 Anode 12 Cathode 13 Electrolyte 14 Hull 15 Reduction gear 16 Propeller shaft 17 Propeller 23 Wiring 26 Diesel engine 27 Spark ignition engine 28 Fuel oil tank 29 Liquid fuel tank 30 Water tank

Claims (1)

[Claims] In a ship provided with a methanol storage tank for transporting methanol therein, an oxygen storage tank and methanol extracted from the methanol storage tank are converted into a mixed gas of hydrogen and carbon dioxide. A hydrogen separator for separating hydrogen from the mixed gas, and a direct current for generating a direct current by a chemical reaction between hydrogen from the hydrogen separator and oxygen from the oxygen storage tank. An electrically propelled methanol transport ship, comprising: a fuel cell; and an electric motor that operates using the fuel cell as a power source and rotates a propeller.