KR102439810B1 - Fuel Supply System with Filter Cleaning Function for Pump of LNG Fuel Tank - Google Patents

Abstract

The present invention relates to a fuel supply system with a filter cleaning function for a liquefied natural gas (LNG) fuel tank pump. To this end, according to the present invention, the fuel supply system with a filter cleaning function for an LNG fuel tank pump is characterized in that it consists of an LNG fuel tank, a supply line, a suction line, a recovery line, a branch line, a boil-off gas (BOG) compression line, a bypass line, and an inlet port. As a result, it is possible to efficiently clean the filter provided in the pump without opening the LNG fuel tank, and there is an effect of blocking in advance the case where the discharge amount of the pump is reduced due to the suction side of the pump being blocked.

Description

Fuel Supply System with Filter Cleaning Function for Pump of LNG Fuel Tank

The present invention relates to a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump capable of efficiently cleaning a filter provided in the pump without opening the LNG fuel tank in a ship using LNG fuel.

In the case of an LNG fuel supply system, natural gas in gaseous state is supplied to the engine after meeting a certain temperature and pressure required by the engine through a pump and a heat exchanger to supply LNG as fuel.

In the case of ships, in order to satisfy a certain pressure of natural gas to be supplied as fuel, a pump (Submerged Pump, hereinafter referred to as 'pump') that is an LNG FEED PUMP is installed inside the LNG fuel tank to supply the pressure required to the engine. A pump pressurization method and a method in which LNG in the tank is increased to the pressure required by the engine without a pump and then supplied to the engine through a heat exchanger are used.

However, in the case of an LNG fuel tank, it is manufactured through many processes, and in the case of a tank that has been manufactured in this way, various metal fragments or sludge remaining during manufacturing, such as washing, remain, and such metal fragments or sludge, etc. In order to prevent inflow into the pump, a fine filter of 10 to 20 mesh is provided on the suction side to prevent inflow.

However, as time passes, when metal fragments or sludge accumulate and accumulate, the fine filter is clogged, and as a result, the suction side filter of the pump is blocked to reduce the discharge amount of the pump.

In such a case, in order to clean the filter provided in the pump in the tank, a method of opening the tank and directly entering and cleaning the tank is widely used.

Accordingly, there is a need to develop a technology for stably and stably supplying fuel by efficiently cleaning the filter provided in the pump without opening the tank.

Republic of Korea Patent Publication 10-2015-0114744 (published date: October 13, 2015) Korean Patent Laid-Open Patent No. 10-2010-0033037 (published on March 29, 2010)

The present invention has been devised to solve the above problems, and provides a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump capable of efficiently cleaning a filter provided in the pump without opening the LNG fuel tank. there is a purpose to

In addition, the present invention can block in advance the case where the discharge amount of the pump is reduced because the suction side of the pump is blocked, and as a result, stable fuel supply is possible, and thus, it is also an object to secure stability according to operation.

Together with this, other objects and advantages of the present invention will be described below, which are further provided by means and combinations within the scope that can be easily derived therefrom, as well as the disclosure of the matters described in the claims of the present invention and examples thereof. It is added that it will be covered in a wide range.

In order to achieve the above object, a fuel supply system with a filter cleaning function for an LNG fuel tank pump according to the present invention accommodates liquid fuel and gaseous fuel, and a first LNG fuel tank in which a first pump is provided in the liquid fuel. ; a first supply line for supplying liquid fuel at a constant pressure from the first pump, in which a first connection valve and a second connection valve are respectively installed; a first suction line connecting the lower side of the first pump and the first connecting valve and the second connecting valve of the first supply line, wherein a fourth connecting valve and a fifth connecting valve are respectively installed; Branched between the first connection valve and the second connection valve of the first supply line and connected to the first LNG fuel tank, a sixth connection valve, a first eject, a first filter, and a seventh connection valve are sequentially a first recovery line installed as a first branch line branched between the fourth connection valve and the fifth connection valve of the first suction line and connected to the first ejector of the first recovery line, in which an eighth connection valve is installed; a first BOG compression line receiving gaseous fuel from the first LNG fuel tank, compressing it, and then supplying it between the sixth connection valve and the first ejection of the recovery line, in which a ninth connection valve is installed; a bypass line interconnecting the inlet and outlet sides of the first connection valve of the first supply line; and a first inlet port through which gas supplied from an external pressure source is introduced between the first pump and the first connection valve of the first supply line.

To this end, the first supply line is connected to a demand, and a third connection valve and a first main filter are installed, respectively.

And according to a preferred embodiment of the present invention, a second LNG fuel tank accommodating liquid fuel and gaseous fuel, and having a second pump in the liquid fuel; a second supply line for supplying liquid fuel at a constant pressure from the second pump, in which an 11th connection valve and a 12th connection valve are respectively installed; a second suction line connecting the lower side of the second pump and the 11th connection valve and the 12th connection valve of the second supply line, the 14th connection valve and the 15th connection valve being installed respectively; Branched between the 11th connection valve and the 12th connection valve of the second supply line to be connected to the second LNG fuel tank, the 16th connection valve, the second ejection, the second filter, and the 17th connection valve are sequentially a second recovery line to be installed; a second branch line branched between the 14 th connection valve and the 15 th connection valve of the second suction line and connected to the second ejector of the second recovery line, in which an 18 th connection valve is installed; a second BOG compression line that receives gaseous fuel from the second LNG fuel tank, compresses it, and is supplied between the 16th connection valve and the second ejection of the recovery line, in which a 19th connection valve is installed; a bypass line connecting the inlet and outlet sides of the eleventh connection valve of the second supply line; and a second inlet port through which a gas supplied from an external pressure source is introduced between the second pump and the eleventh connection valve of the second supply line, wherein the second supply line includes the first supply line characterized in that it is interconnected with

As described above, according to the present invention, it is possible to efficiently clean the filter provided in the pump without opening the LNG fuel tank, which is expected to significantly reduce the time and cost of cleaning the filter.

In addition, it can be applied to the case of one or more LNG fuel tanks, and the effect of effectively cleaning the filter provided in the pump of the LNG fuel tank is possible only by adding a simple configuration to the existing fuel supply system. is also expected

In addition, since the filter can be periodically cleaned, it is possible to prevent a case in which the discharge amount of the pump is reduced due to blockage of the suction side of the pump.

1 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a first preferred embodiment of the present invention.
2 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a second preferred embodiment of the present invention.
3 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a third preferred embodiment of the present invention.
4 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a fourth preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention and methods of achieving them before the description will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings.

And it should be noted that the terminology used in this specification is for describing the embodiments and is not intended to limit the present invention, and the words indicating a direction in the description are for helping the understanding of the description and may be changed according to time points.

Hereinafter, the present invention will be described in more detail with respect to preferred embodiments of the present invention based on the drawings.

First, the system according to the present invention uses a fuel supply system having a supply line for supplying liquid fuel from an existing LNG fuel tank, further comprising a configuration in which a filter cleaning function for an LNG fuel tank pump is provided. should be understood as

In addition, the embodiment of the present invention is divided into a case in which there is one LNG fuel tank and a case in which there are two LNG fuel tanks. Case 4 corresponds to a case where there are two LNG fuel tanks, and in addition, according to a preferred embodiment of the present invention, the filter cleaning function for the LNG fuel tank pump is to be performed while the pumps are all stopped. bar

1 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a first preferred embodiment of the present invention, and FIG. 2 is an LNG fuel tank according to a second preferred embodiment of the present invention. It is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for a pump.

As mentioned above, FIGS. 1 and 2 show preferred embodiments 1 and 2 according to the present invention, and both correspond to the case of one LNG fuel tank.

1, the present invention is largely a first LNG fuel tank 100, a first supply line 200, a first suction line 300, a first recovery line 400, a first branch line ( 500 ), a first BOG compression line 600 , a bypass line 700 and an inlet port 800 .

First, the LNG fuel tank 100 contains boil-off gas (hereinafter, referred to as 'gas fuel') in the upper evaporation space and LNG (hereinafter referred to as "liquid fuel") stored in the lower portion, and the liquid fuel contains A first pump (5, Submerged Pump) for supplying liquid fuel to the engine at a constant pressure is provided.

Typically, on the suction side of the first pump 5, a fine filter 45 of 10 to 20 mesh is provided on the suction side to prevent various metal fragments or sludge remaining inside the tank from flowing into the pump. to prevent ingress.

The first supply line 200 supplies the liquid fuel of the first LNG fuel tank from the first pump 5 at a constant pressure, and includes a first connection valve 10 and a second connection valve 20 . are respectively installed from the first pump (5).

Here, the first pump 5 may be composed of two or more as needed, and the fuel supply system leading to the LNG fuel tank, the first pump, and the first supply line 200 is the same as the existing one, It may be sent to a place of use such as a boiler to be described later and connected to be used as fuel, or sent to a separate storage tank, or sent to the atmosphere to pass through a filtering device.

Next, according to a preferred embodiment of the present invention, the first suction line 300 is the lower side of the first pump 5 and the first connection valve 10 and the second connection valve of the first supply line. As a connection between ( 20 ), a fourth connection valve ( 40 ) and a fifth connection valve ( 50 ) are respectively installed from the lower side of the first pump ( 5 ).

The first recovery line 400 is branched between the first connection valve 10 and the second connection valve 20 of the first supply line 200 and is connected to the first LNG fuel tank 100 . That is, the sixth connection valve 60 , the first ejector 25 , the first filter 35 and the seventh connection valve 70 are sequentially installed, respectively.

The first branch line 500 is branched between the fourth connection valve 40 and the fifth connection valve 50 of the first suction line 300 and is connected to the first ejector 25 of the first recovery line and To be connected, the eighth connection valve 80 is installed.

The first BOG compression line 600 receives gaseous fuel from the first LNG fuel tank 100 and compresses it, and then the sixth connection valve 60 and the first ejection 25 of the first recovery line. To be supplied between, the ninth connection valve 90 is installed.

In addition, the inlet and outlet sides of the first connection valve 10 of the first supply line 200 are interconnected by a bypass line 700 , and when the first connection valve 10 is closed, the bypass line (700) is passed.

Between the first pump 5 and the first connection valve 10 of the first supply line 200, an external pressure source, more specifically compressed nitrogen (Compressed N2) or gas such as BOG is introduced One inlet port 800 is provided, and a separate connection valve is also provided in the first inlet port 800 .

First, before describing a preferred embodiment of the present invention, the connection valve installed in each line is a valve that can open and close the flow path, and unless it is specifically stated that it is an open state, it should be understood as a closed state, and also a preferred embodiment of the present invention to clarify once again that the pump is also implemented in a stopped state.

(Example 1)

A first preferred embodiment of the present invention will be described with reference to FIG. 1 as follows.

Here, the first embodiment is an effective embodiment when the pressure inside the LNG fuel tank is relatively high, about 3Bar.

First, when the pressure inside the LNG fuel tank is high, when a higher pressure source, more specifically, compressed nitrogen or BOG is connected to the first inlet port 800 of the first supply line 200 , the first The debris or sludge attached to the filter 45 on the lower side of the pump 5 falls off by the high pressure of compressed nitrogen or BOG, and the lower part of the first LNG fuel tank 100, more specifically, a recessed well-shaped space. will gather at

After the compressed nitrogen or BOG is repeatedly introduced several times through the first inlet port 800 of the first supply line 200 , the fourth connecting valve 40 and the fifth of the first suction line 300 are When the connection valve 50 is opened, the liquid fuel containing the debris or sludge is supplied along the first suction line 300 by the pressure inside the LNG fuel tank 100, and also the second connection valve 20 When it is opened, it is supplied through the first supply line 200 .

At this time, the first supply line 200 is the same as the supply line of the existing fuel supply system, and is connected to a boiler to be described later and used as fuel, or is sent to a separate storage tank, or sent to the atmosphere to filter the device. You can also make it go through.

On the other hand, according to a preferred embodiment of the present invention, the first supply line 200 may be connected to a demand destination as shown in FIG. 1 , and in this case, the first supply line 200 has a third connection valve 30 . and a first main filter 15 are installed, respectively.

That is, the liquid fuel from which debris or sludge has been removed through the first main filter 15 is supplied to a consumer at a relatively lower pressure than the internal pressure of the LNG fuel tank 100 , for example, the boiler 7 (Boiler). and can be consumed as fuel.

(Example 2)

A second preferred embodiment of the present invention will be described with reference to FIG. 2 as follows.

First, when the ninth connection valve 90 of the first BOG compression line 600 is opened, the gas fuel is supplied from the first LNG fuel tank 100 and the compressed BOG is supplied to the first recovery line 400 . and distributed to both sides. At this time, when the sixth connecting valve 60 and the seventh connecting valve 70 are opened, a portion of the compressed BOG passes through the first ejection 25 and the first filter 35 and then the LNG fuel tank The remaining portion is supplied to the first supply line 200 and is introduced into the pump 5 through the bypass line 700 .

As a result, debris or sludge attached to the filter 45 on the lower side of the pump 5 falls by the BOG compressed with a high forward force from the first BOG compression line 600 , so that the lower portion of the first LNG fuel tank 100 . , more specifically, they gather in a recessed well-shaped space.

At this time, the first ejector 25 provided in the first recovery line 400 is operated, and the fourth connection valve 40 of the first suction line 300 and the eighth connection valve of the first branch line 500 are operated. When the 80 is opened, the debris or sludge separated from the filter 45 on the lower side of the pump 5 by the first ejector 25 is sucked into the first suction line 300 and the first branch line 500 ) is introduced into the first ejector 25 , and the introduced debris or sludge passes through the first ejector 25 and is caught in the first filter 35 .

If this process is repeated several times, the debris or sludge attached to the filter 45 on the lower side of the pump 5 is repeatedly dropped by the BOG compressed with a high forward force, so that the can be caught

The above second embodiment can be said to be a useful embodiment when the pressure inside the LNG fuel tank is relatively lower than the compressed BOG supplied with gaseous fuel from the first LNG fuel tank 100 .

3 is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for an LNG fuel tank pump according to a third preferred embodiment of the present invention, and FIG. 4 is an LNG fuel tank according to a fourth preferred embodiment of the present invention. It is a schematic configuration diagram of a fuel supply system equipped with a filter cleaning function for a pump.

As mentioned above, Examples 3 and 4 both correspond to the case of having two LNG fuel tanks, and as shown in FIGS. 3 and 4 , the same configuration as all the configurations mentioned in Example 1 is further included. should be understood to be

Therefore, the configuration mentioned in Example 1 above will be cited as it is because it is the same, and in order to be distinguished only from the configuration mentioned in Example 1 above, the additionally provided configuration is "first" -> "second" and They are marked together, and only the reference numerals of the connection valves are different, but the terms referring to them are to be marked the same.

That is, the second LNG fuel tank 100', the second supply line 200', the second suction line 300', the second recovery line 400', the second separation line 500', the second All configurations consisting of the BOG compression line 600 ′, the second bypass line 700 ′ and the second inlet port 800 ′ are the first LNG fuel tank 100 , the first supply line 200 , and the first The suction line 300 , the first recovery line 400 , the first separation line 500 , the first BOG compression line 600 , the first bypass line 700 , and the second inlet port 800 are the same. .

However, according to a preferred embodiment of the present invention, as shown in FIGS. 3 and 4 , the second supply line 200 ′ is characterized in that it is interconnected with the first supply line 200 . More specifically, the second supply line 200 ′ is preferably connected between the second connection valve 20 and the third connection valve 30 of the first supply line 200 .

(Example 3)

Hereinafter, a third preferred embodiment of the present invention will be described with reference to FIG. 3 .

The third embodiment can be called a useful embodiment when the internal pressure of the first LNG fuel tank 100 is relatively higher than the internal pressure of the second LNG fuel tank 100'.

First, as shown, when the pressure inside the first LNG fuel tank 100 is high, a higher pressure source, more specifically, compressed nitrogen or BOG is supplied to the first inlet port of the first supply line 200 . When connected to 800, the debris or sludge attached to the filter 45 on the lower side of the first pump 5 falls off by the high pressure of compressed nitrogen or BOG to the lower part of the first LNG fuel tank 100, More specifically, they gather in a hollow well-shaped space.

At this time, the fourth connection valve 40 and the fifth connection valve 50 of the first suction line 300 provided on the side of the first LNG fuel tank 100 , and the second connection of the first supply line 200 . The valve 20 is opened, and the 12th connection valve 20' of the second supply line 200' provided on the side of the second LNG fuel tank 100' and the 16th of the second recovery line 400' are opened. When the connection valve 60' and the 17th connection valve 70' are opened, the internal pressure of the first LNG fuel tank 100 is relatively higher than the internal pressure of the second LNG fuel tank 100'. The debris or sludge passes through the first suction line 300, the first supply line 200, the second supply line 200', and the second recovery line 400' together with the liquid fuel in sequence to the second LNG fuel tank. (100') will be supplied.

The debris or sludge passing through the second ejector 25' of the second recovery line 400' is caught in the second filter 35', and if this process is repeated several times, compressed nitrogen or BOG The debris or sludge attached to the filter 45 on the lower side of the pump 5 of the first LNG fuel tank 100 repeatedly falls by the high pressure of the They can all be caught by the second filter 35'.

(Example 4)

Next, FIG. 4 describes a fourth preferred embodiment of the present invention as follows.

Conversely, the fourth embodiment can be called a useful embodiment when the internal pressure of the first LNG fuel tank 100 is relatively lower than the internal pressure of the second LNG fuel tank 100'.

First, as shown, the eleventh connection valve 10 ′ and the twelfth connection valve 20 ′ of the second supply line 200 ′, and the second connection valve 20 of the first supply line 200 are connected to each other. When opened, the liquid fuel is supplied to the first supply line 200 through the second supply line 200 ′ at a high pressure by the pump 5 ′ of the second LNG fuel tank 100 ′.

At this time, when the sixth connection valve 60 and the seventh connection valve 70 of the first recovery line 400 are opened and the first connection valve 10 of the first supply line 200 is closed, the first supply line Part of the liquid fuel passing through 200 flows into the first recovery line 400 and flows into the first LNG fuel tank 100 , and the remaining part flows through the first bypass line 700 through the pump 5 ) is introduced into

As a result, debris or sludge attached to the filter 45 on the lower side of the pump 5 falls from the pump 5' of the second LNG fuel tank 100' by the high pressure liquid fuel, and the first LNG They are gathered in the lower part of the fuel tank 100 , more specifically in a recessed well-shaped space.

At this time, the first ejector 25 provided in the first recovery line 400 is operated, and the fourth connection valve 40 of the first suction line 300 and the eighth connection valve of the first branch line 500 are operated. When the 80 is opened, the debris or sludge separated from the filter 45 on the lower side of the pump 5 by the first ejector 25 is sucked into the first suction line 300 and the first branch line 500 ) is introduced into the first ejector 25 , and the introduced debris or sludge passes through the first ejector 25 and is caught in the first filter 35 .

If this process is repeated several times, the debris or sludge attached to the filter 45 on the lower side of the pump 5 is repeatedly dropped by the liquid fuel of the high front force and finally completely caught by the first filter 35. can get

On the other hand, on the other hand, it goes without saying that debris or sludge attached to the filter on the lower side of the pump 5' of the second LNG fuel tank 100' can also be removed when this method is applied.

Therefore, according to the present invention, debris or sludge attached to the filter on the lower side of the pump of the LNG fuel tank can be removed without opening the fuel tank. Or it has the advantage that it is only replaced.

In addition, it can be applied to the case of one or more LNG fuel tanks, and it is possible to effectively clean the filter provided in the pump of the LNG fuel tank only by adding a simple configuration to the existing fuel supply system.

And, above all, it is possible to periodically clean the filter, so that the suction side of the pump is clogged and the discharge amount of the pump is reduced in advance.

The above description is merely illustrative of the technical idea of the present invention, and a person skilled in the art to which the present invention pertains may make various modifications, changes and substitutions within the scope without departing from the essential characteristics of the present invention. is of course

100, 100': 1st, 2nd LNG fuel tank 200, 200': 1st, 2nd supply line
300, 300': first and second suction lines 400, 400': first and second return lines
500, 500': 1st, 2nd branch line 600, 600': 1st, 2nd BOG compression line
700, 700': first and second bypass lines 800, 800': first and second inlet ports

Claims (3)

a first LNG fuel tank accommodating liquid fuel and gaseous fuel and having a first pump in the liquid fuel;
a first supply line for supplying liquid fuel at a constant pressure from the first pump, in which a first connection valve and a second connection valve are respectively installed;
a first suction line connecting the lower side of the first pump and the first connecting valve and the second connecting valve of the first supply line, wherein a fourth connecting valve and a fifth connecting valve are respectively installed;
Branched between the first connection valve and the second connection valve of the first supply line and connected to the first LNG fuel tank, a sixth connection valve, a first eject, a first filter, and a seventh connection valve are sequentially a first recovery line installed as
a first branch line branched between the fourth connection valve and the fifth connection valve of the first suction line and connected to the first ejector of the first recovery line, in which an eighth connection valve is installed;
a first BOG compression line that receives gaseous fuel from the first LNG fuel tank, compresses it, and is supplied between the sixth connection valve and the first ejection line of the recovery line, in which a ninth connection valve is installed;
a bypass line interconnecting the inlet and outlet sides of the first connection valve of the first supply line; and
Between the first pump and the first connection valve of the first supply line, a first inlet port through which gas supplied from an external pressure source is introduced is provided. fuel supply system.
The method of claim 1,
The first supply line is connected to a customer, and a fuel supply system with a filter cleaning function for an LNG fuel tank pump, characterized in that a third connection valve and a first main filter are installed, respectively.
The method of claim 1,
a second LNG fuel tank accommodating liquid fuel and gaseous fuel and having a second pump in the liquid fuel;
a second supply line for supplying liquid fuel at a constant pressure from the second pump, in which an 11th connection valve and a 12th connection valve are respectively installed;
a second suction line connecting the lower side of the second pump and the 11th connection valve and the 12th connection valve of the second supply line, the 14th connection valve and the 15th connection valve being installed respectively;
Branched between the 11th connection valve and the 12th connection valve of the second supply line to be connected to the second LNG fuel tank, the 16th connection valve, the second ejection, the second filter, and the 17th connection valve are sequentially a second recovery line to be installed;
a second branch line branched between the 14 th connection valve and the 15 th connection valve of the second suction line and connected to the second ejector of the second recovery line, in which an 18 th connection valve is installed;
a second BOG compression line that receives gaseous fuel from the second LNG fuel tank, compresses it, and is supplied between the 16th connection valve and the second ejection of the recovery line, in which a 19th connection valve is installed;
a bypass line connecting the inlet and outlet sides of the eleventh connection valve of the second supply line; and
Between the second pump and the eleventh connection valve of the second supply line, a second inlet port through which a gas supplied from an external pressure source is introduced further comprises,
The second supply line,
A fuel supply system having a filter cleaning function for an LNG fuel tank pump, characterized in that it is interconnected with the first supply line.

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