KR20140059599A - A system for suppling fuel gas of ship and a method thereof - Google Patents

Abstract

A system for supplying fuel gas of ships according to the present invention supplies fuel gas to a main engine for propulsion of high-pressure gas injection type and to an accessory engine for power generation of low-pressure gas injection type from a storage tank. The system comprises a vent piping for transferring vent gas, obtained after discharging evaporation gas, to control internal pressure of the storage tank, a vent piping for transferring vent gas discharged to control pressures exceeded at each component devices of the system or at connections between component devices, and a low-pressure tank connected with the vent piping to suck the vent gas; and is characterized by transferring vent gas collected in the low-pressure tank to a high-pressure tank to be supplied as additional fuel gas for the accessory engine. The system for supplying fuel gas of ships further comprises a storage tank for storing liquefied fuel, a sucking drum for sucking the liquefied fuel from the storage tank, a vaporizer for transferring the liquefied fuel inside the sucking drum by a booster pump and a high-pressure pump to be vaporized; and is characterized by supplying the liquefied fuel gas, vaporized through the vaporizer, to the main engine and the accessory engine through a transfer piping and a bypass piping, respectively. Further, when the main engine is in a standby mode, fuel gas is supplied to the accessory engine by being bypassed from the transfer piping to the bypass piping rather than being supplied to the main engine.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel gas supply system for a ship,

The present invention relates to a fuel gas supply system and method for a ship, and more particularly, to a fuel supply system for a liquefied fuel transportation vessel that simplifies and simplifies a fuel supply structure from a liquefied fuel storage tank to a cycle engine and a view engine, And a fuel gas supply system and method for utilizing the vent gas discharged from each of the components as an additional fuel for the engine.

Recently, interest in liquefied fuel gas, which is much cheaper than that of heavy oil, but which is a clean energy source, for example, propulsion engines using LNG (or LPG, DME) as fuel is increasing due to the rise in oil prices.

As a marine engine capable of obtaining propulsion power using liquefied fuel gas as a fuel, there is a high pressure gas injection type cycle engine such as ME-GI (Gas Injection Engine of Man B & W).

As an example of LNG carriers using liquefied natural gas (LNG) as a fuel, an LNG tank for storing LNG is located in the LNG carrier. Since the liquefaction temperature of natural gas is a cryogenic temperature of -163 ° C at normal pressure, LNG is evaporated even if its temperature is slightly higher than the normal pressure of -163 ° C. LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank LNG tank Off Gas (BOG) occurs. When the evaporation gas accumulates in the LNG tank, the pressure in the LNG tank rises excessively, so that the evaporated gas is vented (hereinafter referred to as "vent") and discharged to the air or incinerated by the gas burner.

In addition, fuel gas may be vented to the air, or may be sent to the combustor and incinerated if the constituent devices of the fuel gas supply system and the connecting portions of the respective constituent devices inevitably exceed the set pressure range for operational and safety reasons.

Hereinafter, the evaporated gas vented in the liquefied fuel storage tank, and the fuel gas vented at the connecting parts of the constituent devices and the respective constituent devices will be collectively referred to as 'vent gas'.

This amount of vent gas is economically disadvantageous, and when it is discharged into the air without combustion, it acts as a greenhouse gas and causes various environmental problems such as global warming.

As a method for reusing the evaporation gas, the evaporation gas generated in the LNG tank is re-liquefied by the evaporation gas re-liquefaction device and returned to the LNG tank. As the propulsion fuel of the LNG carrier, LNG stored in the LNG tank It is possible to consider a method of using it by vaporizing it. Fig. 1 is a view showing a schematic configuration of a fuel gas supply system of such a conventional LNG carrier. In this system, the evaporated gas discharged from the LNG tank 1 is compressed in the compressor 2 via the evaporated gas discharge line L1, and then re-liquefied through the Reliquefaction Unit 3. The re-liquefied evaporated gas is again sent to the LNG tank (1). The propulsion of the LNG carriers is carried out by extracting the LNG stored in the LNG tank 1, compressing the LNG at a high pressure by the high-pressure pump 5, vaporizing it in the vaporizer 6, and burning it in the cycle engine.

When the vent gas is re-liquefied in such a manner, a process of compressing a large amount of vent gas to a high pressure corresponding to the operating pressure of the cycle turbine and cooling it to a cryogenic temperature is required, which is not economically significant.

On the other hand, the LNG carriers are equipped with a low-pressure gas injection engine, such as a dual fuel diesel electric propulsion system (DFDE) engine or a gas turbine, to produce the necessary electricity in a ship or to be used as an engine for an emergency.

As described above, in the case where a cycle engine used for propulsion and a view engine used for power generation are respectively provided in a ship such as an LNG carrier, a fuel gas supply line, a pump, a vaporizer, and the like are separately installed . This complicates the configuration of the fuel gas supply system of the liquefied fuel gas propulsion vessel such as the LNG carrier and increases the installation space.

In order to solve the above-described problems, the present invention provides a fuel supply system that is economically reusable without exhausting or burning vent gas, simplifies the structure of the fuel supply system by unifying the fuel supply system separately configured for the cycle engine and the view engine, And it is an object of the present invention to provide a fuel gas supply system and method for supplying fuel to a view engine in a stable state without any additional equipment even in a standby state of the engine.

In order to achieve the above object, the present invention provides a fuel gas supply system for a ship, which supplies fuel gas from a storage tank to a propulsion cycle engine of a high pressure gas injection system and a view engine for power generation of a low pressure gas injection system, A vent pipe for transferring the vent gas discharging the evaporation gas to regulate the internal pressure of the storage tank, a vent pipe for transferring the vent gas to control the excess pressure at the connection between each constituent device or the constituent devices of the system And a low pressure tank connected to the vent pipe for sucking the vent gas. The vent gas collected in the low pressure tank is supplied to the high pressure tank as additional fuel gas of the view engine.

Also, the fuel gas supply system of the ship includes a storage tank for storing the liquefied fuel, a suction drum for sucking the liquefied fuel from the storage tank, and a vaporizer for transferring the liquefied fuel in the suction drum through the booster pump and the high- Wherein the vaporized fuel gas passes through the vaporizer and is supplied to the cycle engine and the view engine through the transfer pipe and the bypass pipe, respectively. When the cycle engine is in the standby mode, the fuel gas is not supplied to the cycle engine but is bypassed from the transfer pipe to the bypass pipe and supplied to the view engine.

The present invention has the effect of reducing operating cost and preventing environmental pollution by reusing the vent gas without discharging or burning it. At the same time, it is possible to simplify the structure of the fuel supply system by unifying the fuel supply system with respect to the cycle engine and the view engine, and it is possible to supply the fuel to the engine, .

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a configuration diagram showing a fuel gas supply system for a ship according to the prior art; Fig.
2 is a configuration diagram illustrating a fuel gas supply system for a ship according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The present invention relates to a system and method for i) the economical recycling of vent gas into additional fuel gas of an engine without venting or discharging it into the air, ii) simplifying the structure of the fuel supply system by unifying the fuel supply system of the cycle engine and the view engine And more particularly, to a fuel gas supply system and method for supplying fuel to a view engine in a stable state without a separate facility even in a standby state of a cyclic engine.

First, the structure and operation of i) vent gas reuse will be described in detail.

1 is a schematic view showing a fuel gas supply system for a ship according to an embodiment of the present invention.

One embodiment of the present invention relates to the use of the vapor gas generated in a liquefied fuel storage tank (hereinafter referred to as 'storage tank') as fuel for the engine 200. The storage tank 10 vaporizes the liquefied fuel during operation and generates a large amount of vapor gas. Generally, the generated steam gas is discharged into the air or burned. In an embodiment of the present invention, this vapor gas is vented to the low-pressure tank 300 using vent pipe (v1) without discharging it into the air or burning it. The low pressure tank 300 is installed with a suction compressor 310 at its outlet side to effectively suck the vent gas.

The suction compressor 310 is designed to maintain at least the pressure in the low-pressure tank 300 at a pressure lower than the vent gas discharged from the storage tank 10.

The suction compressor 310 serves to transfer the vent gas to the high-pressure tank 70. At this time, it is preferable to compress the vent gas at least to a pressure at least equal to or higher than the pressure inside the high-pressure tank 70 for smooth transportation.

In order to precisely control the pressure of the vent gas delivered to the high pressure tank 70, an adjusting valve 320 is preferably provided between the suction compressor 310 and the high pressure tank 70. And further includes a pressure sensor 321 so that the vent gas can be delivered to the set pressure.

A logic turn valve 330 is provided between the suction compressor 310 and the high pressure tank 70 so that the fuel gas does not flow back to the suction compressor 310 from the high pressure tank 70.

Another embodiment of the present invention relates to reusing the vent gas vented at the connections between each component and each component of the fuel gas supply system.

Here, the above-mentioned constitution means that it includes the suction drum 20, the booster pump 30, the high-pressure pump 40, the orifice 53 of the vaporizer 50, and various tanks, valves, . The connecting portion between the constituent devices is collectively referred to as a pipe of the transfer pipe 51, the bypass pipe 52 and the like, and a joint portion of the constituent device and the pipe.

1, the vent pipe v2 extending from the suction drum 20 is shown as an example. However, the vent pipe v2 is not limited to the suction drum 20 but may be variously connected to the connecting portion between the constituent device and the constituent devices And the vent gas is fed.

The vent pipe v2 leads to the low-pressure tank 300 in the same manner as the vent pipe v1 described above. Then, the vent gas is supplied to the engine 200 through the same process as the above-described embodiment.

The two embodiments may be implemented at the same time by using one low-pressure tank 300, or may be made by using a plurality of low-pressure tanks 300 in some cases.

The above description can be summarized as follows. A venting step of discharging the vent gas to adjust the pressure of the storage tank 10 and the suction drum 20 provided at the outlet side of the storage tank. And a transfer step of transferring the vent gas discharged from the vent stage to the low pressure tank through the vent piping v1 and v2. The low pressure tank 300 connected to the vent piping v1 (v2) And a suction step of collecting the vent gas. Pressure tank 300 to the additional fuel gas of the view engine 200. The low-

1 shows a unified fuel gas supply system for supplying fuel gas to the cycle engine 100 and the view engine 100. However, the reuse of the vent gas described above does not affect the characteristics of the engine 200 ), That is, a unified fuel gas supply system.

Ii) Simplifying the structure of the fuel supply system by unifying the fuel supply system of the cycle engine and the view engine, which is the second feature of the present invention, The supply will be described in detail.

1, a fuel gas supply system for a ship according to the present invention includes a storage tank 10 for storing liquefied fuel, a suction drum 20 for sucking liquefied fuel from the storage tank 10, And a vaporizer (50) for transferring the liquefied fuel in the drum (20) through the booster pump (30) and the high - pressure pump (40) so as to be vaporized.

The fuel gas vaporized while passing through the vaporizer 50 is supplied to the cycle engine 100 and the view engine 200. The fuel gas is supplied to the cycle engine 100 according to the operation conditions of the cycle engine 100 Bypassed from the transfer pipe 51 to the bypass pipe 52, and supplied to the view engine 200 without being bypassed.

The bypass pipe 52 is provided with a regulating valve 60, a high-pressure tank 70, a regulating valve 80 and a heat exchanger 90 to control the pressure of the engine 200 (Low-pressure state).

The above-mentioned vent gas is further introduced into the high-pressure tank 70 and supplied to the view engine 200 together.

An orifice 53 for reducing pressure is provided in front of the adjustment valve 60 and a non-return valve 54 is provided between the adjustment valve 60 and the high-pressure tank 70 .

In the heat exchanger 90, the natural gas bypassed through the bypass pipe 52 is depressurized and transferred through the orifice 53. Since the temperature of the natural gas is reduced during the depressurization (by the Joule-Thomson principle) Temperature to 45 degrees, and can be exchanged with the cooling water through the water jacket or the steam generated from the boiler.

The control valves 60 and 80 are connected to pressure sensors 61 and 81 for sensing the pressure of the fuel gas and controlling the opening degree of the control valves 60 and 80, respectively.

The liquefied fuel is sucked from the storage tank 10 through the suction drum 20 and then the liquefied fuel is supplied to the vaporizer 30 by the booster pump 30 and the high pressure pump 40. In this case, (50).

The liquefied fuel passes through the vaporizer 50 and is vaporized into a fuel gas which is sent to the cycle engine 100 and the view engine 200 when the fuel gas is in a normal operating state, The temperature of the fuel gas supplied is generally 45 degrees and the pressure is maintained at 300 bar.

However, if the cycle engine 100 is in a standby state, that is, in a low load operation or when the ship is anchored, the cycle engine 100 does not use the fuel gas, The fuel gas in the fuel tank must be re-transferred to the suction drum 20 for storage or a separate storage facility must be provided.

Therefore, in this case, the high-pressure fuel gas is cut off through the gas train (not shown) in the cycle engine 100 itself, and then the high-pressure fuel gas is supplied to the transfer pipe 51 after the vaporizer 50, The bypass pipe 52 to the view engine 200, thereby eliminating the safety problem due to the high pressure, and eliminating the need to install a separate recovery and storage facility.

In other words, the orifice 53 provided on the bypass pipe 52 is decompressed while the high-pressure fuel gas passes through the regulator valve 60. Subsequently, the solenoid valve 54 and the high-pressure tank 70, The valve 80 and the heat exchanger 90 are sequentially supplied to the view engine 200. The above-mentioned vent gas is further introduced into the high-pressure tank 70 and supplied to the view engine 200 together.

The high-pressure fuel gas passing through the orifice 53 is reduced in pressure and cooled down to zero. The fuel gas is heat-exchanged while passing through the heat exchanger 90, and is supplied to the engine 200 in a state where the temperature is raised to 45 degrees.

At this time, the pressure of the fuel gas required in the view engine 200 is usually about 4 to 6 bar. The pressure of the fuel gas generated through the vaporizer 50 is 300 bar, and the orifice 53 And the gas pressure required by the engine 200 is adjusted.

If the pressure of the fuel gas passing through the orifice 53 is sensed by the pressure sensor 61 of the regulating valve 60, the opening degree of the regulating valve 60 is appropriately adjusted.

In addition, the high-pressure tank 70 plays a role of buffering and serves to catch the gas pulsation phenomenon according to the engine load.

The control valve 80 after the high-pressure tank 70 is also provided with a pressure sensor 81 to sense the pressure of the fuel gas passing through the high-pressure tank 70 and appropriately adjust the opening of the control valve 80 .

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims and their equivalents. It will be possible. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

10: Storage tank 20: Suction drum
30: booster pump 40: high pressure pump
50: vaporizer 51: transfer pipe
52: bypass piping 53: orifice
54: logic turn valve 60: adjustment valve
61: pressure sensor 70: high pressure tank
80: regulating valve 81: pressure sensor
90: Heat exchanger 100: Cycle engine
200: view engine 300: low pressure tank
310: Suction compressor 320: Adjustment valve
321: pressure sensor 330: logic turn valve
v1, v2: Vent piping

Claims (20)

1. A fuel gas supply system for a ship that supplies fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high-pressure gas injection system and a view engine for power generation of a low-pressure gas injection system,
A vent pipe (v1) for transferring vent gas discharged from the storage tank (10) to regulate the internal pressure of the storage tank (10); And
And a low pressure tank (300) connected to the vent pipe (v1) for sucking the vent gas,
Pressure tank (300) to the additional fuel gas of the view engine (200).
1. A fuel gas supply system for a ship that supplies fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high-pressure gas injection system and a view engine for power generation of a low-pressure gas injection system,
A vent pipe (v2) connected to a connecting portion between the constituent devices or the constituent devices of the system, for transferring the vent gas discharged to control the excess pressure; And
And a low pressure tank (300) connected to the vent pipe (v2) and sucking the vent gas,
Pressure tank (300) to the additional fuel gas of the view engine (200).
1. A fuel gas supply system for a ship that supplies fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high-pressure gas injection system and a view engine for power generation of a low-pressure gas injection system,
A vent pipe (v1) for transferring vent gas discharged from the storage tank (10) to regulate the internal pressure of the storage tank (10);
A vent pipe (v2) for transferring the discharged vent gas to control excess pressure at a connection between each constituent device or constituent device of the system; And
And a low pressure tank (300) connected to the vent pipe (v1) (v2) for sucking the vent gas,
Pressure tank (300) to the additional fuel gas of the view engine (200).
The method according to claim 2 or 3,
Characterized in that the constituent device comprises a suction drum (20).
4. The method according to any one of claims 1 to 3,
Pressure tank 300 and maintains the internal pressure of the low-pressure tank 300 at a pressure lower than the pressure of the vent gas discharged from the storage tank 10 to the inside of the low-pressure tank 300 And a suction compressor (310) for introducing the vent gas.
4. The method according to any one of claims 1 to 3,
A suction drum (20) for sucking liquefied fuel from the storage tank;
A pump unit connected to the suction drum to compress and convey the liquefied fuel; And
And a carburetor (50) for vaporizing the liquefied fuel transferred through the pump section into a fuel gas,
The vaporized fuel gas is supplied to the cycle engine 100 and the view engine 200 through the transfer pipe 51 and the bypass pipe 52 while passing through the vaporizer 50. [
The method of claim 6,
The fuel gas is bypassed from the transfer pipe 51 to the bypass pipe 52 without being supplied to the cycle engine 100 so that the engine 200 is operated in the standby mode, To the fuel gas supply system.
The method according to claim 6,
Wherein the pump unit comprises a booster pump (30) and a high-pressure pump (40).
The method according to claim 6,
The bypass pipe 52 is provided with an orifice 53 for reducing pressure and an adjusting valve 60 for supplying combustion gas in a state in which the pressure is adjusted by the view engine 200 and a high pressure tank 70, 80) and a heat exchanger (90).
6. The method of claim 5,
Wherein the suction compressor (310) compresses the vent gas at a pressure equal to or higher than the internal pressure of the high pressure tank (70).
The method according to claim 6,
The control valve 320 may further include a control valve 320 disposed between the suction compressor 310 and the high-pressure tank 70 so that the pressure of the vent gas transferred from the suction compressor 310 to the high- And the fuel gas supply system of the ship.
12. The method of claim 11,
Wherein a logic turn valve (54) (330) is provided between the adjustment valve (60) (320) and the high-pressure tank (70).
13. The method of claim 12,
Wherein the control valves (60), (80) and (320) are connected to pressure sensors (61), (81) and (321) for detecting the outlet side pressure, respectively.
A method for supplying fuel gas to a ship for supplying fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high pressure gas injection system and a view engine (200) for power generation of a low pressure gas injection system,
A vent stage for discharging the evaporation gas as a vent gas to regulate the internal pressure of the storage tank;
A transfer step of transferring the vent gas discharged from the vent stage to the low pressure tank through the vent pipe v1; And
And a suction step of collecting the vent gas into a low pressure tank (300) connected to the vent pipe (v1)
Pressure tank (300) to the additional fuel gas of the view engine (200).
A method for supplying fuel gas to a ship for supplying fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high pressure gas injection system and a view engine (200) for power generation of a low pressure gas injection system,
A vent stage for discharging the vent gas from the suction drum (20) provided at the outlet side of the storage tank (10);
A transfer step of transferring the vent gas discharged from the vent stage to the low pressure tank 300 through the vent pipe v2; And
And a suction step of collecting the vent gas into a low pressure tank (300) connected to the vent pipe (v2)
Pressure tank (300) to the additional fuel gas of the view engine (200).
A method for supplying fuel gas to a ship for supplying fuel gas from a storage tank (10) to a propulsion cycle engine (100) of a high pressure gas injection system and a view engine (200) for power generation of a low pressure gas injection system,
A vent stage for discharging the vent gas to adjust the pressure of the storage tank (10) and the suction drum (20) provided at the outlet side of the storage tank;
A transfer step of transferring the vent gas discharged from the vent stage to the low pressure tank through the vent pipe v1 (v2); And
And a suction step of collecting the vent gas into a low pressure tank (300) connected to the vent pipe (v1) (v2)
Pressure tank (300) to the additional fuel gas of the view engine (200).
17. The method according to any one of claims 14 to 16,
Wherein,
A suction compressor 310 is provided at the outlet of the low pressure tank 300 to maintain the internal pressure of the low pressure tank 300 at a pressure lower than the pressure of the vent gas discharged from the storage tank 10, Wherein the vent gas is introduced into the vessel (300).
17. The method according to any one of claims 14 to 16,
Suck liquefied fuel into the suction drum 20 connected to the storage tank 10,
The liquefied fuel is compressed and transferred to the booster pump 30 and the high-pressure pump 40, which are sequentially connected to the suction drum,
The compressed and transferred liquefied fuel is vaporized in the vaporizer (50) into a fuel gas,
Wherein the vaporized fuel gas is supplied to the cycle engine (100) and the view engine (200) through the transfer pipe (51) and the bypass pipe (52) while passing through the vaporizer (50).
19. The method of claim 18,
The fuel gas is bypassed from the transfer pipe 51 to the bypass pipe 52 without being supplied to the cycle engine 100 so that the engine 200 is operated in the standby mode, ) Of the fuel gas to be supplied to the ship.
20. The method of claim 19,
An orifice 53 is provided in the bypass pipe 52 so as to reduce the pressure of the fuel gas and further includes a regulating valve 60, a high-pressure tank 70, a regulating valve 80 and a heat exchanger 90, So that the combustion gas is supplied to the engine (200) while the pressure is adjusted.

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