KR101499161B1 - Fuel supply system and fuel supply method - Google Patents

Abstract

Fuel supply system. A fuel supply system according to an embodiment of the present invention is a fuel supply system for supplying fuel gas to an engine of a ship. The fuel supply system includes a storage tank storing liquefied fuel, a first pump connected to the storage tank and compressing the liquefied fuel, A first pump connected to the first pump and compressing the compressed liquefied fuel again, a first vaporizer connected to the second pump and supplying the compressed liquefied fuel to the engine, A second vaporizer for vaporizing the liquefied fuel pumped by the first vaporizer, and a first compression unit connected to the second vaporizer to compress the liquefied fuel vaporized in the second vaporizer and supply the liquefied fuel to the engine.

Description

[0001] Fuel supply system and fuel supply method [0002]

The present invention relates to a fuel supply system and a fuel supply method.

Vessels can be propelled using liquefied natural gas (LNG) as fuel. For this purpose, ships may be equipped with liquefied natural gas storage tanks for storing liquefied natural gas for fuel.

In the case where a high pressure gas injection engine such as the ME-GI engine (a product of MAN B & W Piesel) is used as the propulsion engine of such a vessel, a conventional fuel supply system for supplying fuel to the high pressure gas injection engine includes a liquefied natural gas storage tank Pressure gas injection engine converts low-pressure fuel gas stored in the storage tank to high pressure to supply fuel.

To this end, the fuel supply system may include a compressor for compressing the fuel of the storage tank to a high pressure and a vaporizer for vaporizing the compressed fuel.

The high-pressure gas injection engine may be equipped with a high-pressure pump for compressing the fuel to a high pressure. In case of breakage of such high pressure pump during operation of the vessel, the operation of the vessel shall be stopped and replaced or repaired. In order to replace the high-pressure pump, a new high-pressure pump is generally provided on the ship. Accordingly, in order to provide a high-pressure pump, not only a separate cost is required but also it is difficult to efficiently utilize the space inside the ship.

An embodiment of the present invention is to provide a fuel supply system and a fuel supply method that can operate even when a high-pressure pump is broken even if a separate high-pressure pump is not provided.

A fuel supply system according to one aspect of the present invention is a fuel supply system for supplying a fuel gas to an engine of a ship, comprising: a storage tank storing liquefied fuel; a first pump connected to the storage tank to pressurize the liquefied fuel; A second pump connected to the first pump for pressurizing the pressurized liquefied fuel again; a first vaporizer connected to the second pump and for vaporizing the pressurized liquefied fuel; a second vaporizer connected to the first pump, A second vaporizer for vaporizing the pumped liquefied fuel and a first compression unit connected to the second vaporizer to compress the liquefied fuel vaporized in the second vaporizer and supply the liquefied fuel to the engine.

In this case, when the operation of the second pump is impossible, the controller may block the movement of the liquefied fuel with the second pump.

At this time, the control unit may include a valve provided at a portion branched from the first compression unit on a pipe connecting the first pump and the second pump.

At this time, the valve may be a switch valve that allows the liquefied fuel to be transported to only one of the second pump and the first compression section.

At this time, the first compression unit can compress the object step by step by connecting the compressor and the vaporizer in series with each other alternately.

The system may further include a second compression unit connected to the storage tank and the first compression unit to compress the gaseous liquefied fuel in the storage tank and transfer the compressed liquefied fuel to the first compression unit.

At this time, the second compression unit can compress the object step by step by connecting the compressor and the vaporizer in series with each other alternately.

The fuel supply method according to one aspect of the present invention is a fuel supply method for supplying liquefied fuel stored in the storage tank to the engine in the fuel supply system according to any one of claims 1 to 7, When the failure occurs in the first pump, the liquefied fuel pressurized by the first pump is bypassed to the first compression section, and when the second pump is normally operated, The second pump can be moved to the second pump without being bypassed.

At this time, the liquefied fuel stored in the storage tank may be stepwise pressurized while passing through the first pump and the second pump in a liquid state.

The fuel supply system according to an embodiment of the present invention configured as described above can quickly bypass the flow of liquefied fuel to the first compression unit when a failure occurs due to damage to the internal parts of the second pump, The flow to the pump is shut off and the liquefied fuel is compressed by the first pump and the first compression unit to supply fuel to the engine. Accordingly, the operation of the ship can be continued without stopping.

In this manner, in the fuel supply system according to the embodiment of the present invention, the operation of the ship is not stopped when the second pump fails. In addition, since the second pump, which is a high-pressure pump, is not required to be carried on the vessel separately, no additional cost is required for providing the high-pressure pump. In addition, the space inside the vessel can be efficiently utilized as much as the space occupied by the high-pressure pump.

1 is a schematic view showing a fuel supply system according to an embodiment of the present invention;
2 is a schematic view showing a fuel supply system according to another embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" between other parts. Also, when a part is referred to as "including " an element, it does not exclude other elements unless specifically stated otherwise.

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

Referring to FIG. 1, a fuel supply system 100 according to an embodiment of the present invention is a fuel supply system 100 for supplying fuel gas to a ship's engine 101, including a storage tank 110, A first pump 120, a second pump 130, a first vaporizer 140, a second vaporizer 150, and a first compression unit 160.

In the storage tank 110, liquefied fuel is stored. Here, the liquefied fuel may be any one of LNG (Liquefied Natural Gas), LPG (Liquefied Petroleum Gas), and DME (Dimethylether), but is not limited thereto. Hereinafter, for convenience of explanation, it is assumed that the liquefied fuel is LNG.

The liquefied fuel may be stored at a temperature of approximately -163 ° C. The storage tank 110 may be, for example, a storage tank for storing liquefied fuel in a liquefied fuel carrier. Alternatively, the storage tank 110 may be a tank storing a liquefied fuel for use as fuel by providing a separate space for storing the liquefied fuel in the liquefied fuel carrier.

A boosting pump 111 may be disposed inside the storage tank 110. The boosting pump 111 pumps the liquefied fuel stored inside the storage tank 110 to the outside. More preferably, the boosting pump 111 pumps the liquefied fuel into the liquid state to the first pump 120, which will be described later.

The first pump 120 is connected to the storage tank 110 to pressurize the liquefied fuel. The first pump 120 pumps and pressurizes the liquefied fuel in the liquid state transferred from the storage tank 110. The first pump 120 may be a low pressure pump, for example. The low pressure pump pressurizes, for example, the liquefied fuel of approximately 1 bar (gauge pressure) stored in the storage tank 110 to approximately 20 bar.

The second pump 130 is connected to the first pump 120. The second pump 130 pressurizes the pressurized liquefied fuel again. More specifically, the second pump 130 is connected to the first pump 120 on the backward basis with respect to the flow direction of the liquefied fuel, and pressurizes the liquefied fuel pressurized by the first pump 120 again. The second pump 130 may be connected to the first pump 120 by the first pipe L1.

The second pump 130 may be, for example, a high pressure pump. The high pressure pump again pressurizes, for example, approximately 20 bar of liquefied fuel primarily pressurized by the first pump 120 to approximately 250 bar or more.

The first vaporizer 140 is connected to the second pump 130. The first vaporizer 140 vaporizes the pressurized liquefied fuel and supplies it to the engine 101. The first vaporizer 140 may be a heater, for example. The first vaporizer 140 vaporizes the liquid fuel in the liquid state finally pressurized by the second pump 130 and supplies it to the engine 101 of the ship.

On the other hand, the engine 101 installed on the ship receives the liquefied fuel from the first vaporizer 140. The engine 101 may be, for example, a high-pressure gas injection engine 101 operated by high-pressure fuel. The high-pressure gas injection engine 101 may be operated by liquefied fuel at a pressure of about 250 bar or more.

The second vaporizer 150 is connected to the first pump 120 to vaporize the liquefied fuel pumped by the first pump 120. The second vaporizer 150 may be, for example, a heater. The second vaporizer 150 vaporizes the liquefied fuel in the liquid state pressurized by the first pump 120.

The second vaporizer 150 may be installed on the second pipe L2 branched from the first pipe L1. That is, one end of the second pipe L2 may be branched from a part of the first pipe L1 and the other end may be connected to the first compression unit 160, which will be described later.

The first compression unit 160 is connected to the second vaporizer 150 and compresses the vaporized liquefied fuel in the second vaporizer 150 and supplies the compressed liquefied fuel to the engine 101. The first compression unit 160 compresses the gaseous liquefied fuel unlike the first pump 120 and the second pump 130 described above. This first compression portion 160 is pressurized by the first pump 120 to bring the liquefied fuel having a pressure of approximately 20 bar to a pressure of approximately 250 bar or more.

The detailed structure of the first compression unit 160 for this purpose may be one in which the compressor and the vaporizer are alternately connected in series to compress the object step by step. Here, the object may be a boil-off gas (BOG) formed in the storage tank 110 or a liquefied fuel vaporized by the second vaporizer 150. The liquefied fuel vaporized in the second vaporizer (150) can be compressed in multiple stages by the first compression unit (160).

Meanwhile, the fuel supply system 100 according to an embodiment of the present invention may include a control unit not shown. If the operation of the second pump 130 is not possible, the control unit blocks the movement of the liquefied fuel by the second pump 130. The control unit may be, for example, a microprocessor.

The detailed structure of the control part for this purpose may include, for example, a valve not shown. The valve may be installed on a portion of the piping connecting the first pump 120 and the second pump 130 to the first compression portion 160. More specifically, the valve may be installed at a portion where the second pipe L2 branches from the first pipe L1.

Such a valve may be a switch valve that allows the liquefied fuel to be delivered only to either the second pump 130 or the first compression section 160. If the operation of the second pump 130 is not possible by the switch valve, the flow of the liquefied fuel to the second pump 130 is blocked to prevent the liquefied fuel from being transferred to the second pump 130. In the state where the second pump 130 operates normally, the liquefied fuel can be moved only to the second pump 130 through the first pump 120.

In the fuel supply system 100 according to an embodiment of the present invention configured as described above, when a failure occurs due to damage to internal parts of the second pump 130, The first pump 120 and the first compression unit 160 compress the liquefied fuel to supply the fuel to the engine 101. The first pump 120 and the first compression unit 160 compress the liquefied fuel. Accordingly, the operation of the ship can be continued without stopping.

In this way, in the fuel supply system 100 according to the embodiment of the present invention, even if the failure of the second pump 130 occurs, the operation of the ship may not be stopped. In addition, since the second pump 130, which is a high-pressure pump, is not additionally provided on two or more vessels, no additional cost is required for providing the high-pressure pump. In addition, the space inside the vessel can be efficiently utilized as much as the space occupied by the high-pressure pump.

2 is a schematic view showing a fuel supply system according to another embodiment of the present invention.

Referring to FIG. 2, the fuel supply system 200 according to another embodiment of the present invention may further include a second compression unit 270.

The second compression unit 270 is configured to connect the storage tank and the first compression unit 160 to compress the gaseous liquefied fuel in the storage tank and transfer it to the first compression unit 160. More specifically, the second compression unit 270 may be formed on the third pipe L3 connecting the second pipe L2 and the storage tank 110. [ One end of the third pipe L3 may be branched from a portion of the second pipe L2 and the other end may be formed to communicate with the upper side of the storage tank 110. [ The detailed structure of the second compression unit 270 for this purpose may be one in which the compressor and the vaporizer are alternately connected in series to compress the object step by step. Here, the object may be vaporized gas formed in the storage tank 110. The vaporized gas can be compressed in multiple stages by the second compression unit (270).

The fuel supply system 100 according to an embodiment of the present invention may be configured to supply fuel to the engine by the second compression unit 270 in two ways.

One method is to use a boil-off gas (BOG) formed on the upper side of the interior of the storage tank 110 as fuel for the engine 101. In this method, the gasified gas is compressed through the second compression portion 270. The compressed gasified gas is compressed again through the first compression unit 160. The compressed vaporized gas again is supplied to the engine 101 so that the engine 101 can be operated.

Alternatively, the liquefied fuel in the liquid state stored in the storage tank 110 is used as the fuel for the engine 101 in another method. The liquefied fuel in the liquid state is pumped by the boosting pump 111 and is preferentially pressurized by the first pump 120 and pressurized by the second pump 130 again. The liquefied fuel in the pressurized liquid state is supplied to the engine 101 through the first vaporizer 140 again. When the second pump 130 fails, the liquefied fuel passes through the first pump 120 and the first compression unit 170 and is compressed and supplied to the engine.

When the vaporized gas is sufficiently formed in the storage tank 110 as described above, the vaporized gas is used as the fuel for the engine 101. [ Alternatively, when the vaporized gas is not sufficient inside the storage tank 110, the liquefied fuel in the liquid state is used as the fuel for the engine 101. [ That is, the fuel supply system 100 according to another embodiment of the present invention may be configured to selectively use the vaporized gas and the liquefied fuel in the storage tank 110.

According to another aspect of the present invention, there is provided a fuel supply method for supplying liquefied fuel stored in a storage tank in a fuel supply system constructed as described above to the engine, , The liquefied fuel pressurized by the first pump is bypassed to the first compression unit. When the second pump is normally operated, the liquefied fuel pressurized by the first pump is allowed to move to the second pump without being bypassed to the first compression unit. With this fuel supply method, as described above, even if a failure occurs in the second pump, the engine can be continuously operated.

Meanwhile, the liquefied fuel stored in the storage tank may be stepwise pressurized while passing through the first pump and the second pump in a liquid state. The method of stepwise pressurizing the liquefied fuel can improve the pressurization reliability and prevent the pump from overloading because it does not need to increase the pressure suddenly, as compared with pressurizing the liquefied fuel at a time.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, And are not used to limit the scope of the present invention described in the scope. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: fuel supply system 101: engine
110: Storage tank 111: Boosting pump
120: first pump 130: second pump
140: first vaporizer 150: second vaporizer
160: first compression section 270: second compression section
L1: first pipe L2: second pipe
L3: Third piping

Claims (9)

A fuel supply system for supplying fuel gas to an engine of a ship,
A storage tank in which the liquefied fuel is stored,
A first pump connected to the storage tank for pressurizing the liquefied fuel,
A second pump connected to the first pump for pressurizing the pressurized liquefied fuel again,
A first vaporizer connected to the second pump for vaporizing the pressurized liquefied fuel,
A second vaporizer connected to the first pump for vaporizing the liquefied fuel pumped by the first pump, and
And a first compression unit connected to the second vaporizer for compressing and supplying the liquefied fuel vaporized in the second vaporizer to the engine. The method according to claim 1,
And a control unit for blocking the movement of the liquefied fuel with the second pump when the operation of the second pump is impossible. 3. The method of claim 2,
Wherein,
And a valve provided on a portion of the piping connecting the first pump and the second pump to be branched to the first compression portion. The method of claim 3,
Wherein the valve is a switch valve that causes the liquefied fuel to be delivered only to either the second pump or the first compression section. The method according to claim 1,
Wherein the first compression unit comprises:
A fuel supply system in which a compressor and a vaporizer are alternately connected in series to compress an object stepwise. The method according to claim 1,
Further comprising: a second compression unit configured to connect the storage tank and the first compression unit and compress the gaseous liquefied fuel in the storage tank to transfer the gaseous liquefied fuel to the first compression unit. The method according to claim 6,
Wherein the second compression unit comprises:
A fuel supply system in which a compressor and a vaporizer are alternately connected in series to compress an object stepwise. 8. A fuel supply method for supplying liquefied fuel stored in the storage tank to the engine in the fuel supply system according to any one of claims 1 to 7,
When a failure occurs in the second pump, the liquefied fuel pressurized by the first pump is bypassed to the first compression unit,
Wherein when the second pump is normally operated, the liquefied fuel pressurized by the first pump is moved to the second pump without being bypassed to the first compression section. 9. The method of claim 8,
Wherein the liquefied fuel stored in the storage tank is stepwise pressurized while passing through the first pump and the second pump in a liquid state.

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