KR102111202B1 - Liquefied Gas Treatment System and Liquefied Gas Carrier having the same - Google Patents

Abstract

The present invention relates to a liquefied gas treatment system and a liquefied gas carrier having the same, wherein the liquefied gas treatment system of the present invention is supplied with a second evaporation gas generated in a second liquefied gas storage tank, and a second liquefied gas inside Knockout drum filled with; And heat-exchanging the second liquefied gas filled in the knockout drum with a first liquefied gas supplied from a first liquefied gas storage tank to a consumer, or generated in the first liquefied gas and the first liquefied gas storage tank. It includes a heat exchanger for heat exchange with 1 evaporation gas, the second liquefied gas is in a supercooled state in the heat exchanger, the second evaporation gas is re-liquefied by spraying the second liquefied gas in the knockout drum into the knockout drum It is characterized by being.

Description

Liquefied Gas Treatment System and Liquefied Gas Carrier having the same}

The present invention relates to a liquefied gas treatment system and a liquefied gas carrier having the same.

As the demand for reduction of environmental pollutants such as SO _x , NO _x , and CO ₂ generated during operation in ships increases, and these environmental problems and regulations related to ship and exhaust emissions are strengthened, the existing fuel oil Rather, a ship that operates LNG (Liquefied Natural Gas), which is a clean fuel, is being adopted. Ships using such LNG as propulsion fuel must have a separate device for fueling LNG.

In order to reduce the volume of the first liquefied gas storage tank of a ship using LNG as propulsion fuel, the fuel is stored as liquefied natural gas LNG, and vaporized LNG through a fuel supply device to use LNG as fuel. All the cold heat generated at this time is discharged to the outside.

On the other hand, LPG (Liquefied Petroleum Gas), such as ethylene, ammonia, etc., carriers that store and transport liquefied gas, which is generally stored in a liquid state, in a liquefied gas storage tank and transport the liquefied gas by evaporation due to natural gas intrusion during operation. Boil off gas (BOG) is generated to increase the internal pressure of the liquefied gas storage tank, and to re-liquefy the evaporated gas to eliminate the risk of tank damage caused by the increased pressure inside the liquefied gas storage tank. Various methods have been studied to recycle evaporated gas, such as re-liquefying and recovering it into a liquefied gas storage tank.

However, the re-liquefaction device applied to the existing liquefied gas carriers compresses the evaporation gas generated in the liquefied gas storage tank and liquefies it using seawater.The compressor for compressing the evaporation gas is composed of two or three stages. , Inter-cooler is installed between each compressor to lower the temperature of the fluid, and a part of the liquefied gas liquefied using seawater enters the inter-cooler through Joule Thompson (JT). Flash gas at a temperature is mixed with hot gas that has passed through a compressor to re-liquefy the evaporated gas by lowering the temperature. However, the existing re-liquefaction apparatus includes the above-described complex components, alone or It is configured in parallel and has a problem of increasing energy consumption and system construction cost.

The present invention was created to solve the problems of the prior art as described above, and the object of the present invention is to recover boil-off gas generated from LPG stored in the second liquefied gas storage tank using LNG stored in the first liquefied gas storage tank. By liquefaction, it is to provide a liquefied gas treatment system and a liquefied gas carrier having the same, which can simplify the components of the reliquefaction apparatus and reduce energy consumption and system construction cost of the reliquefaction apparatus.

Another object of the present invention is to increase the temperature of LNG supplied from the first liquefied gas storage tank to the engine by using the boil-off gas generated from the LPG stored in the second liquefied gas storage tank, when LNG to be used as fuel for the engine is vaporized It is to provide a liquefied gas treatment system and a liquefied gas carrier having the same can easily obtain the heat required for the.

Liquefied gas processing system according to an aspect of the present invention is supplied with a second evaporation gas generated in the second liquefied gas storage tank, a knockout drum filled with a second liquefied gas therein; And heat-exchanging the second liquefied gas filled in the knockout drum with a first liquefied gas supplied from a first liquefied gas storage tank to a consumer, or generated in the first liquefied gas and the first liquefied gas storage tank. It includes a heat exchanger for heat exchange with 1 evaporation gas, the second liquefied gas is in a supercooled state in the heat exchanger, the second evaporation gas is re-liquefied by spraying the second liquefied gas in the knockout drum into the knockout drum It is characterized by being.

Specifically, the first liquefied gas is LNG, the second liquefied gas is LPG, and the heat exchanger may be an LNG-LPG heat exchanger or an LNG-LPG-BOG (LNG) heat exchanger.

Specifically, a fuel supply device is provided in a first line connected from the first liquefied gas storage tank to the demand destination, and the fuel supply device includes: the heat exchanger provided on the first line; A first pump provided on the first line between the first liquefied gas storage tank and the heat exchanger to pressurize the first liquefied gas; And a heater provided on the first line between the heat exchanger and the customer and heating the first liquefied gas to a temperature required by the customer.

Specifically, the fuel supply apparatus further includes a compressor provided on a fourth line, one end of which is connected to the upper portion of the first liquefied gas storage tank, and the other end of which is connected to the interior of the first liquefied gas storage tank. can do.

Specifically, the heat exchanger is provided on the fourth line between the compressor and the first liquefied gas storage tank, the compressor. Provided on the fourth line between the first liquefied gas storage tank and the heat exchanger, the first evaporation gas generated in the first liquefied gas storage tank may be pressurized and supplied to the heat exchanger.

Specifically, a second line having one end connected to the upper portion of the second liquefied gas storage tank, the other end connected to the inside of the second liquefied gas storage tank, and one end connected to the second line, the other end A third line connected to the knockout drum is provided with a reliquefaction device, and the reliquefaction device comprises: the knockout drum provided on the second line; The heat exchanger provided on the third line; The knockout drum and the second liquefied gas storage tank are provided on the second line, and the second liquefied gas discharged from the knockout drum is recovered through the second line to the second liquefied gas storage tank or the It may include a second pump to pressurize to supply to the heat exchanger through a third line.

Specifically, the re-liquefaction apparatus further includes a water level control valve provided on the second line downstream of the connection point of the third line connected between the second pump and the second liquefied gas storage tank, The water level control valve is opened when the level of the second liquefied gas inside the knockout drum is higher than a certain level so that the second liquefied gas is recovered through the second line to the second liquefied gas storage tank, If it is lower than a certain water level, it can be closed to control the second liquefied gas to be supplied to the heat exchanger through the third line.

Specifically, the knock-out drum, the second liquefied gas in the supercooled state injected therein to reduce the internal pressure due to re-liquefying the second evaporation gas is generated in the second liquefied gas storage tank the second Since the boil-off gas is continuously drawn in as a natural flow along the second line, it can function as a boil-off gas supply equipment.

A liquefied gas carrier according to another aspect of the invention is characterized by including the liquefied gas treatment system described above.

The liquefied gas treatment system according to the present invention and the liquefied gas carrier having the same are configured such that the fuel supply device and the reliquefaction device are connected, so that the second liquefied gas storage tank using the first liquefied gas stored in the first liquefied gas storage tank It is possible to improve the efficiency of the re-liquefaction of the evaporation gas generated from, thereby simplifying the components of the re-liquefaction device, as well as reducing the energy consumption and system construction cost of the re-liquefaction device.

In addition, the liquefied gas treatment system according to the present invention and the liquefied gas carrier having the same are configured such that the fuel supply device and the reliquefaction device are connected, so that the first liquefied gas supplied from the first liquefied gas storage tank to the engine is second liquefied Heat exchanged with the boil-off gas generated in the gas storage tank, the first liquefied gas to be used as fuel for the engine can be easily obtained from the boil-off gas during vaporization, thereby improving the energy efficiency of LNG fuel supplied to the engine. .

1 is a view showing a liquefied gas carrier to which the liquefied gas treatment system according to the present invention is applied.
2 is a conceptual diagram of a liquefied gas treatment system according to a first embodiment of the present invention.
3 is a conceptual diagram of a liquefied gas treatment system according to a second embodiment of the present invention.
4 is a conceptual diagram of a liquefied gas treatment system according to a third embodiment of the present invention.
5 is a conceptual diagram of a liquefied gas treatment system according to a fourth embodiment of the present invention.
6 is a conceptual diagram of a liquefied gas treatment system according to a fifth embodiment of the present invention.
7 is a conceptual diagram of a liquefied gas treatment system according to a sixth embodiment of the present invention.
8 is a conceptual diagram of a liquefied gas treatment system according to a seventh embodiment of the present invention.
9 is a conceptual diagram of a liquefied gas treatment system according to an eighth embodiment of the present invention.
10 is a conceptual diagram of a liquefied gas treatment system according to a ninth embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the accompanying drawings. It should be noted that in this specification, when adding reference numerals to the components of each drawing, the same components have the same number as possible even though they are displayed on different drawings. In addition, in the description of the present invention, when it is determined that detailed descriptions of related known technologies may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

Hereinafter, in the present specification, liquefied gas may be used in a sense to encompass all gas fuels generally stored in a liquid state, such as LNG, LPG, ethylene, ammonia, and the like. Can be expressed as Boil-off gas (BOG) may also be applied.

In addition, in the present invention, LNG is the first liquefied gas and LPG may be referred to as the second liquefied gas, wherein the boiling point of the first liquefied gas may be relatively lower than that of the second liquefied gas. Here, the first liquefied gas may be limited to methane, which is a main component of LNG, and the second liquefied gas may be limited to propane, butane, and ethane, which are components of LPG.

Of course, the present invention does not limit the first liquefied gas and the second liquefied gas to LNG and LPG, respectively, and the first liquefied gas and the second liquefied gas mean not only LNG and LPG, but also all liquefied gases having different boiling points. Can be.

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

1 is a view showing a liquefied gas carrier to which the liquefied gas treatment system according to the present invention is applied.

As shown in FIG. 1, the liquefied gas carrier 1 uses the first liquefied gas stored in the liquid state in the first liquefied gas storage tank 20 as fuel for the engine 30, and inside the hull 10 It may be a vessel that stores the second liquefied gas in a liquid state in a plurality of second liquefied gas storage tanks 40 to be transported from the production area to various consumers.

The liquefied gas carrier 1 includes a fuel supply device for vaporizing the first liquefied gas and a second liquefied gas storage in order to use the first liquefied gas stored in the first liquefied gas storage tank 20 as fuel for the engine 30. Various liquefied gas treatment systems (100, 200, 300, 400, 500, 600, 700, 800, 900) configured to be connected to a reliquefaction device for liquefying the boil-off gas generated in the tank 40 may be provided. Here, the configuration of each of the fuel supply device and the reliquefaction device and their associated configurations can be seen by referring to FIGS. 2 to 10.

In the above, the first liquefied gas storage tank 20 stores the first liquefied gas in a liquid state to be supplied as fuel to the engine 30. The first liquefied gas storage tank 20 must store the first liquefied gas in a liquid state, wherein the first liquefied gas storage tank 20 may have a pressure tank shape. The first liquefied gas storage tank 20 may be installed on the same ship as the liquefied gas carrier 1 using the first liquefied gas as fuel for the engine, or may be installed on the ground. When the first liquefied gas stored in the first liquefied gas storage tank 20 is LNG, the LNG stored in the LNG storage tank 20 has a boiling point of -162 ° C under 1 atmosphere.

The engine 30 may be supplied with the first liquefied gas from the first liquefied gas storage tank 20 to generate power to drive the propeller of the liquefied gas carrier 1, and may be an XDF, DFDE, or MEGI engine.

The engine 30 may be an engine for driving a propeller, but may be an engine for generating power or an engine for generating other power. That is, this embodiment does not specifically limit the type of the engine 30. However, the engine 30 may be an internal combustion engine that generates driving force by combustion of the first liquefied gas.

Of course, the present invention describes a case where the engine 30 is a demand destination using the first liquefied gas as a fuel, but is not limited thereto, and evaporates to a demand location using not only the engine 30 but also the first liquefied gas as fuel. Of course, it may include a gas combustion unit (GCU), a boiler, etc. that incinerates gas.

The second liquefied gas storage tank 40 may be installed at least one on a ship or land, and may store the second liquefied gas in a liquid state. In the present invention, a case where the second liquefied gas storage tank 40 is provided inside the hull 10 will be described.

If the second liquefied gas stored in the second liquefied gas storage tank 40 is LPG, among the components of LPG stored in the LPG storage tank 40, in the order of boiling point, ethane (C ₂ H ₆ ) The boiling point is -89.0 ° C under this 1 atmosphere, propane (C ₃ H ₈ ) has a boiling point -42 ° C under 1 atmosphere, and butane (C ₄ H ₁₀ ) has -0.5 ° C under 1 atmosphere. As described above, it can be seen that LPG is very high even when it is stored for each component or when components are stored in a mixed state, considering that the LNG stored in the LNG storage tank 20 has a boiling point of -162 ° C under 1 atmosphere.

2 is a conceptual diagram of a liquefied gas treatment system according to a first embodiment of the present invention.

As shown in Figure 2, the liquefied gas treatment system 100 according to the first embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 110, the heat exchanger 120, It includes a heater 130, a blower (140), a separator 150, a second pump 160, a reliquefaction unit (RELI unit) 170, and a temperature control valve 180.

In the above, the first pump 110, the heat exchanger 120, the heater 130 may be components of the fuel supply device, the heat exchanger 120, the blower 140, the separator 150, the second pump (160), the re-liquefaction unit 170 may be a component of the re-liquefaction apparatus, and the heat exchanger 120 used in common may be configured to link the fuel supply apparatus and the re-liquefaction apparatus.

The above-described components may be provided on the first line 101, the second line 102, and the third line 103.

Specifically, the first line 101 may be connected to the engine 30 from the first liquefied gas storage tank 20, the first liquefied gas stored in the first liquefied gas storage tank 20 to the engine 30 It can be configured to supply. A first pump 110, a heat exchanger 120, and a heater 130 may be provided on the first line 101.

The second line 102 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end may be connected to the interior of the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. A heat exchanger 120, a blower 140, a separator 150, and a second pump 160 may be provided on each of the second lines 102.

The third line 103 has one end connected to the second line 102 between the second liquefied gas storage tank 40 and the blower 140 to be described later, and the other end of the second pump 160 to be described later. 2 may be connected to the second line 102 between the liquefied gas storage tank 40, it may be configured to re-liquefy the evaporation gas generated inside the second liquefied gas storage tank 40. A reliquefaction unit 170 may be provided on the third line 103.

The first pump 110 is provided on the first line 101 between the first liquefied gas storage tank 20 and the heat exchanger 120 to be described later, the first liquefied gas stored in the first liquefied gas storage tank 20 It is possible to pressurize the first liquefied gas discharged from the first liquefied gas storage tank 20 to a pressure required by the engine 30 to supply the engine 30. Of course, the pressure required by the engine 30 may vary depending on the type of the engine 30, for example, XDF, DFDE, MEGI engine.

The heat exchanger 120 may be provided on the first line 101 and the second line 102, and may be an LNG-BOG (LPG) heat exchanger when the first liquefied gas is LNG and the second liquefied gas is LPG. have.

Specifically, the heat exchanger 120 may be located between the first pump 110 and the heater 130 to be described later in the first line 101, and the blower 140 to be described later in the second line 102. It may be located between the separator 150 to be described later.

In the heat exchanger 120, a first liquefied gas having a relatively low boiling point and a second liquefied gas storage tank 40 supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 101 ) Is generated from the second liquefied gas having a relatively high boiling point stored in the interior of the evaporation gas supplied through the second line 102 for re-liquefaction, heat exchange is made, through the heater 130 to be described later engine ( The first liquefied gas supplied to 30) obtains heat by the heat of the boil-off gas generated from the second liquefied gas, so that when the heater 130 is heated to a temperature required by the engine 30, thermal energy can be reduced. Then, the boil-off gas generated in the second liquefied gas storage tank 40 is re-liquefied by obtaining cold heat of the first liquefied gas, thereby increasing the re-liquefaction efficiency of the boil-off gas generated in the second liquefied gas storage tank 40 I can do it.

The heater 130 may be provided on the first line 101 between the engine 30 and the heat exchanger 120, and the first liquefied gas supplied from the first liquefied gas storage tank 20 may be provided to the engine 30. ) Can be heated to the temperature required. In this embodiment, the first liquefied gas supplied to the heater 130 is heated while passing through the heat exchanger 120 provided upstream of the heater 130, so that when the engine 30 is heated to the required temperature, heat energy is You can save.

The heater 130 is used to remove waste heat generated from steam supplied through a boiler (not shown), glycol water supplied from a glycol heater (not shown), electric energy, or a generator or other equipment provided on a ship. Can be used to heat the first liquefied gas.

The blower 140 may be provided on the second line 102 between the second liquefied gas storage tank 40 and the heat exchanger 120, and is generated and discharged inside the second liquefied gas storage tank 40 Pressurized boil-off gas can be supplied to the heat exchanger (120). The blower 140 can reduce power consumption by up to 58% compared to a compressor used in a reliquefaction device.

The separator 150 may be provided on the second line 102 between the heat exchanger 120 and the second pump 160 to be described later, and the liquid phase and gas phase in the evaporated gas cooled while passing through the heat exchanger 120. Can be separated. The separator 150 may recover the second liquefied gas of the liquid-liquid separated liquid into the second liquefied gas storage tank 40.

The second pump 160 may be provided on the second line 102 between the separator 150 and the second liquefied gas storage tank 40, and the second liquefied gas separated in the liquid phase from the separator 150 The second liquefied gas storage tank 40 may be pressurized for easy recovery. The second pump 160 is provided at the rear end of the separator 150 and may be turned on / off according to the level of the second liquefied gas inside the separator 150.

The second liquefied gas separated into the liquid phase from the separator 150 may be recovered into the second liquefied gas storage tank 40 by the compression ratio of the blower 140 and the pressure ratio of the second pump 160, the blower 140 ), The second pump 160 may compensate for a problem that may occur due to a low compression ratio.

The reliquefaction unit 170 may be provided on the third line 103 and re-liquefy the evaporated gas generated in the second liquefied gas storage tank 40.

The reliquefaction unit 170 may be operated in a compatible manner with the heat exchanger 120, for example, may be operated when it is not possible to completely reliquefy the evaporation gas to the heat exchanger 120.

The temperature control valve 180 may be provided on the second line 102 between the heat exchanger 120 and the separator 150.

The temperature control valve 180 is provided at the front end of the separator 150 so as to completely re-liquefy the boil-off gas generated in the second liquefied gas storage tank 40 in the heat exchanger 120, the internal pressure of the separator 150 The degree of opening may be controlled according to the temperature of the front end of the over temperature control valve 180. According to the trajectory of the temperature control valve 180, the amount of the evaporation gas introduced into the heat exchanger 120 is controlled to completely re-liquefy the evaporation gas.

3 is a conceptual diagram of a liquefied gas treatment system according to a second embodiment of the present invention.

As shown in FIG. 3, the liquefied gas treatment system 200 according to the second embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 210 and the heat exchanger 220 , A heater 230, a second pump 240, a separator 250, a reliquefaction unit 260, and an injection nozzle 270.

In the above, the first pump 210, the heat exchanger 220, the heater 230 may be components of the fuel supply device, the heat exchanger 220, the second pump 240, the separator 250, ash The liquefaction unit 260 and the injection nozzle 270 may be components of the reliquefaction apparatus, and the heat exchanger 220 commonly used may be configured to link the fuel supply apparatus and the reliquefaction apparatus.

The above-described components may be provided on the first line 201, the second line 202, and the third line 203.

Specifically, the first line 201 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A first pump 210, a heat exchanger 220, and a heater 230 may be provided on the first line 201.

The second line 202 has one end connected to a second pump 240 to be described later provided on the inner bottom portion of the second liquefied gas storage tank 40, and the other end of the second liquefied gas storage tank 40. It may be connected to the injection nozzle 270 to be described later provided in the interior ceiling portion, it may be configured to circulate the second liquefied gas stored in the interior of the second liquefied gas storage tank 40. A second pump 240, a heat exchanger 220, a separator 250, and a spray nozzle 270 may be provided on the second line 102.

The third line 203 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end is provided in the inner ceiling portion of the second liquefied gas storage tank 40, the injection nozzle 270 to be described later It may be connected to, and may be configured to re-liquefy the boil-off gas generated inside the second liquefied gas storage tank (40). A reliquefaction unit 260 may be provided on the third line 203.

The first pump 210 may be provided on the first line 201 between the first liquefied gas storage tank 20 and the heat exchanger 220 to be described later, the same as the pump 110 of the first embodiment or As a similar component, the description will be omitted here to avoid duplication of the description.

The heat exchanger 220 may be provided on the first line 201 and the second line 202, and may be an LNG-LPG heat exchanger when the first liquefied gas is LNG and the second liquefied gas is LPG.

Specifically, the heat exchanger 220 may be located between the first pump 210 and the heater 230 to be described later in the first line 201, and the second pump 240 to be described later in the second line 202. ) And a separator 250 to be described later.

In the heat exchanger 220, the first liquefied gas having a relatively low boiling point and the second liquefied gas storage tank 40 supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 201 ), The second liquefied gas having a relatively high boiling point, which is recovered through the second line 202 back to the second liquefied gas storage tank 40, is exchanged with each other, and then through the heater 230, which will be described later, the engine 30 ), The first liquefied gas is supplied to the heat by the heat of the second liquefied gas, so that the heater 230 can reduce heat energy when heated to a temperature required by the engine 30, and the second liquefied gas Since the second liquefied gas recovered into the storage tank 40 is cooled to the first liquefied gas to become a supercooled state, generation of evaporated gas in the second liquefied gas storage tank 40 may be fundamentally suppressed.

The heater 230 may be provided on the first line 201 between the engine 30 and the heat exchanger 220, and the same or similar components to the heater 130 of the first embodiment are described here, and thus the overlap of the description will be described. In order to avoid the description will be omitted.

The second pump 240 is provided on the inner bottom portion of the second liquefied gas storage tank 40 and can be connected to the second line 202, and heat exchanges the second liquefied gas stored in the second liquefied gas storage tank 40 The second liquefied gas may be pressurized to be recovered back to the second liquefied gas storage tank 40 via the group 220, the separator 250 to be described later, and the injection nozzle 270 to be described later.

The separator 250 may be provided on the second line 202 between the heat exchanger 220 and the injection nozzle 270 to be described later, and the liquid phase and gas phase in the second liquefied gas via the heat exchanger 220. Separately, the second liquefied gas can be extracted. Since the second liquefied gas passing through the heat exchanger 220 is supercooled by the first liquefied gas, there may be no second liquefied gas in the gas phase inside the separator 250. The separator 250 may allow the second liquefied gas of the liquid-liquid separated liquid to be recovered into the second liquefied gas storage tank 40.

The reliquefaction unit 260 may be provided on the third line 203 and re-liquefy the evaporated gas generated in the second liquefied gas storage tank 40.

A plurality of injection nozzles 270 may be provided on the inner ceiling portion of the second liquefied gas storage tank 40, and may be connected to the second line 202 and the third line 203. The injection nozzle 270 is a second liquefied gas in the supercooled state supplied through the second line 202 and / or the second liquefied gas separated in the liquid phase from the separator 150 supplied through the third line 203. It can be injected from the upper portion of the second liquefied gas storage tank 40, whereby it can be suppressed that the evaporation gas is generated in the second liquefied gas storage tank 40.

4 is a conceptual diagram of a liquefied gas treatment system according to a third embodiment of the present invention.

4, the liquefied gas treatment system 300 according to the third embodiment of the present invention may be provided on a liquefied gas carrier 1, a pump 310, a heat exchanger 320, a compressor ( 330), a separator 340, and a reliquefaction unit 350.

In the above, the pump 310, the heat exchanger 320 may be components of the fuel supply device, the heat exchanger 320, the compressor 330, the separator 340, the reliquefaction unit 350 is a reliquefaction device It may be a component of, and the heat exchanger 320 that is commonly used may be configured to connect a fuel supply device and a reliquefaction device.

The above-described components may be provided on the first line 301, the second line 302, and the third line 303.

Specifically, the first line 301 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A pump 310 and a heat exchanger 320 may be provided on the first line 101.

The second line 302 may have one end connected to the upper portion of the second liquefied gas storage tank 40, the other end connected to the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. A compressor 330, a heat exchanger 320, and a separator 340 may be provided on the second line 302.

The third line 303 is connected to the second line 302 between the compressor 330, which will be described later, and the heat exchanger 320, which will be described later, and the separator 340, which will be described later, and the second liquefied gas storage. It may be connected to the second line 302 between the tanks 40, and may be configured to re-liquefy the boil-off gas generated inside the second liquefied gas storage tank 40. A reliquefaction unit 350 may be provided on the third line 303.

The pump 310 may be provided on the first line 301 between the first liquefied gas storage tank 20 and the heat exchanger 320 to be described later, and the pumps 110 and 210 of the first to second embodiments As the same or similar components, the description will be omitted here to avoid duplication of the description.

The heat exchanger 320 may be provided on the first line 301 and the second line 302, and may be an LNG-BOG (LPG) heat exchanger when the first liquefied gas is LNG and the second liquefied gas is LPG. have.

Specifically, the heat exchanger 320 may be located between the pump 310 and the engine 30 in the first line 301, and in the second line 302 a compressor 330 to be described later and a separator to be described later ( 340).

In the heat exchanger 320, a first liquefied gas having a relatively low boiling point and a second liquefied gas storage tank 40 supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 301 ) Is generated from the second liquefied gas having a relatively high boiling point stored in the interior, the first liquefaction supplied to the engine 30 by heat exchange between the boil-off gas supplied through the second line 302 for re-liquefaction The gas is heated to a temperature required by the engine 30 by the heat of the boil-off gas generated from the second liquefied gas to reduce thermal energy, and the boil-off gas generated in the second liquefied gas storage tank 40 is By re-liquefying by obtaining the cold heat of the first liquefied gas, it is possible to increase the reliquefaction efficiency of the evaporated gas generated in the second liquefied gas storage tank 40.

In the present embodiment, the heating means such as the heaters 130 and 230 of the first or second embodiment is omitted between the heat exchanger 320 and the engine 30, but the present invention is not limited thereto. Or, of course, a heater similar or identical to the heaters 130 and 230 of the second embodiment may be provided.

The compressor 330 may be provided on the second line 302 between the second liquefied gas storage tank 40 and the heat exchanger 320, and is generated and discharged inside the second liquefied gas storage tank 40 The pressurized boil-off gas is pressurized to be supplied to the heat exchanger 320 and the reliquefaction unit 350 to be described later. A plurality of compressors 330 may be provided, and may be arranged in parallel on the second line 302.

The separator 340 may be provided on the second line 302 between the heat exchanger 320 and the second liquefied gas storage tank 40, and the liquid phase from the evaporated gas cooled while passing through the heat exchanger 120. The gas phase can be separated. The separator 340 may allow the second liquefied gas of the gas-liquid separated liquid to be recovered into the second liquefied gas storage tank 40.

The reliquefaction unit 350 may be provided on the third line 303 and re-liquefy the evaporated gas generated in the second liquefied gas storage tank 40 supplied from the compressor 330.

The reliquefaction unit 350 may be operated in a compatible manner with the heat exchanger 320, for example, may be operated when it is not possible to completely reliquefy the evaporation gas to the heat exchanger 320.

5 is a conceptual diagram of a liquefied gas treatment system according to a fourth embodiment of the present invention.

5, the liquefied gas treatment system 400 according to the fourth embodiment of the present invention may be provided on a liquefied gas carrier 1, a pump 410, a heat exchanger 420, a buffer tank 430, a heater 440, a compressor 450, a separator 460.

In the above, the pump 410, the heat exchanger 420, the buffer tank 430, the heater 440 may be components of the fuel supply device, the heat exchanger 420, the buffer tank 430, the compressor 450 ), The separator 460 may be components of the reliquefaction device, and the heat exchanger 420 and the buffer tank 430 commonly used may be configured to link the fuel supply device and the reliquefaction device.

The above-described components may be provided on the first line 401, the second line 402, and the third line 403.

Specifically, the first line 401 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A pump 410, a buffer tank 430, a heat exchanger 420, and a heater 440 may be provided on the first line 4101.

The second line 402 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end may be connected to the interior of the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. A compressor 450, a heat exchanger 420, a separator 460, and a buffer tank 430 may be provided on the second line 402.

The third line 403 has one end connected to the separator 460 to be described later, and the other end connected to the second line 402 between the buffer tank 430 and the second liquefied gas storage tank 40 to be described later. It can be configured to recover the second liquefied gas separated into the liquid in the separator 460 to be described later to the second liquefied gas storage tank 40.

The pump 410 may be provided on the first line 401 between the first liquefied gas storage tank 20 and the buffer tank 430 to be described later, and the pumps 110 and 210 of the first to third embodiments may be provided. 310), the same or similar components will be omitted here to avoid duplication of the description.

The second heat exchanger 420 may be provided on the first line 401 and the second line 402, and when the first liquefied gas is LNG and the second liquefied gas is LPG, LNG-BOG (LPG) heat exchange Can be.

Specifically, the heat exchanger 420 may be located between the buffer tank 430 to be described later in the first line 401 and the heater 440 to be described later, and the compressor 450 to be described later in the second line 402. And a separator 460 to be described later.

In the heat exchanger 420, the first liquefied gas having a relatively low boiling point and the second liquefied gas storage tank 40 supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 401 ) Is generated from the second liquefied gas having a relatively high boiling point stored inside, and circulating through the second line 402 for re-liquefaction, heat exchange between the evaporating gas is performed, and the engine 440 is passed through the heater 440 to be described later. The first liquefied gas supplied to 30) obtains heat by the heat of the boil-off gas generated from the second liquefied gas so that heat energy can be saved when the heater 440 is heated to a temperature required by the engine 30. Then, the boil-off gas generated in the second liquefied gas storage tank 40 is re-liquefied by obtaining cold heat of the first liquefied gas, thereby increasing the re-liquefaction efficiency of the boil-off gas generated in the second liquefied gas storage tank 40 I can do it.

The buffer tank 430 may be provided on the first line 401 and the second line 402, and the first liquefied gas is filled in a certain amount through the first line 401, and the first liquefied gas is The second line 402 may pass through the filled interior. The second line 402 penetrating through the interior of the buffer tank 430 may have various forms including a shell-coil type. The buffer tank 430 may perform an LNG-BOG (LPG) heat exchanger function when the first liquefied gas is LNG and the second liquefied gas is LPG.

Specifically, the buffer tank 430 may be located between the pump 410 in the first line 401 and the heat exchanger 420 to be described later, and the separator 460 and the second line 402 to be described later. 2 may be located between the liquefied gas storage tank 40.

In the buffer tank 430, the first liquefied gas having a relatively low boiling point supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 401, and the gas liquid in the separator 460 to be described later Separately, the second liquefied gas having a relatively high boiling point and circulating through the second line 402 exchanges heat, so that the first liquefied gas supplied to the engine 30 is heated by the evaporation gas. The engine 30 is heated to a temperature required to reduce thermal energy, and the boil-off gas generated in the second liquefied gas storage tank 40 is re-liquefied by obtaining cold heat of the first liquefied gas, thereby liquefying it. It is possible to increase the efficiency of reliquefaction of the evaporated gas generated in the gas storage tank 40.

The above-described buffer tank 430 heats the first liquefied gas supplied from the first liquefied gas storage tank 20 to the engine 30 to a temperature required by the engine 30 similarly to the heat exchanger 420 and removes the liquefied gas. 2 It is possible to perform a function of cooling to a temperature capable of re-liquefying the evaporated gas generated in the liquefied gas storage tank 40, whereby this embodiment is the first by the heat exchanger 420 and the buffer tank 430 The heating of the liquefied gas is performed over the second time, and the re-liquefaction of the evaporated gas is performed over the second time, so that the engine 30 is heated to a temperature required to further reduce thermal energy, and the second liquefied gas is stored. It is possible to further increase the efficiency of reliquefaction of the boil-off gas generated inside the tank 40.

The amount of re-liquefaction of the boil-off gas generated in the second liquefied gas storage tank 40 may be changed according to the load of the engine 20, because the amount of the first liquefied gas used as cold heat is changed. That is, when the load of the engine 20 is large or small, there is a problem that the amount of re-liquefaction must be large or small, which is the amount of re-liquefaction by adjusting the level of the first liquefied gas filled in the buffer tank 430. The level can be controlled. In other words, when the level of the first liquefied gas filled in the buffer tank 430 is increased or decreased, the area where the second line 402 penetrating the inside of the buffer tank 430 contacts the first liquefied gas increases or decreases. The amount of re-liquefaction can be adjusted.

A pump for the purpose of pressurization may be additionally installed at the rear end of the buffer tank 430 according to the required pressure of the engine 20.

The first liquefied gas filled in the inside of the buffer tank 430 may be vaporized while being heat exchanged with the evaporated gas supplied from the second liquefied gas storage tank 40, and the first liquefied gas vaporized inside the buffer tank 430 The boil-off gas of the gas may be recovered to the first liquefied gas storage tank 20 through the fourth line 404 or supplied to the heater 440 through the fifth line 405.

The heater 440 may be provided on the first line 401 between the engine 30 and the heat exchanger 420, and the same or similar components as the heaters 130 and 230 of the first to second embodiments Here, the description will be omitted to avoid duplication of the description.

The compressor 450 may be provided on the second line 402 between the second liquefied gas storage tank 40 and the heat exchanger 420, and is generated and discharged inside the second liquefied gas storage tank 40 Pressurized boil-off gas can be supplied to the heat exchanger (420).

The separator 460 may be provided on the second line 402 between the heat exchanger 420 and the buffer tank 430, and separate the liquid phase and the gas phase from the evaporated gas cooled while passing through the heat exchanger 420. Can be. The separator 460 may allow the vaporized gas of the gas-liquid separated gas phase to be supplied to the buffer tank 430, and the second liquefied gas of the liquid-liquid separated liquid may be recovered to the second liquefied gas storage tank 40. .

That is, the vaporized gas separated in the gas phase from the separator 460 may be supplied to the butter tank 430 through the second line 402 and re-liquefied to be recovered into the second liquefied gas storage tank 40. Further, the second liquefied gas separated into the liquid phase from the separator 460 may be recovered into the second liquefied gas storage tank 40 through the third line 403.

6 is a conceptual diagram of a liquefied gas treatment system according to a fifth embodiment of the present invention.

As shown in Figure 6, the liquefied gas treatment system 500 according to the fifth embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 510, the heat exchanger 520, It includes a heater 530, a knock out drum 540, a second pump 550, and a water level control valve 560.

In the above, the first pump 510, the heat exchanger 520, the heater 530 may be components of the fuel supply device, the heat exchanger 520, the knockout drum 540, the second pump 550, The water level control valve 560 may be components of the reliquefaction device, and the heat exchanger 520 commonly used may be configured to connect the fuel supply device and the reliquefaction device.

The above-described components may be provided on the first line 501, the second line 502, and the third line 503.

Specifically, the first line 501 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A first pump 510, a heat exchanger 520, and a heater 530 may be provided on the first line 501.

The second line 502 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end may be connected to the interior of the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. A knockout drum 540, a second pump 550, and a water level control valve 560 may be provided on the second line 502.

The third line 503 has one end connected to the second line 502 between the second liquefied gas storage tank 40 and the second pump 550 to be described later, and the other end to the knockout drum 540 to be described later. It may be connected, and may be configured to re-liquefy the boil-off gas generated inside the second liquefied gas storage tank 40. A heat exchanger 520 may be provided on the third line 503.

The first pump 510 may be provided on the first line 501 between the first liquefied gas storage tank 20 and the heat exchanger 520 to be described later, and the pumps 110, 1 to 4 of the first embodiment 210, 310, and 410), which are the same or similar components, and thus description will be omitted to avoid duplication of the description.

The heat exchanger 520 may be provided on the first line 501 and the third line 503, and may be an LNG-LPG heat exchanger when the first liquefied gas is LNG and the second liquefied gas is LPG.

Specifically, the heat exchanger 520 may be located between the first pump 510 and the heater 530 to be described later in the first line 501, and may be located in a part of the third line 503.

In the heat exchanger 520, the first liquefied gas having a relatively low boiling point supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 501 and the knockout drum 540 to be described later Since the second liquefied gas having a relatively high boiling point filled therein is exchanged with each other, the first liquefied gas supplied to the engine 30 via the heater 530 to be described later is heated by the evaporation gas generated from the second liquefied gas. When heat is obtained by heating the heater 530 to a temperature required by the engine 30, heat energy can be reduced, and the boil-off drum generated in the second liquefied gas storage tank 40 will be described later. By re-liquefying at 540, it is possible to increase the re-liquefaction efficiency of the evaporated gas generated inside the second liquefied gas storage tank 40.

The boil-off gas generated in the second liquefied gas storage tank 40 may be re-liquefied in the knockout drum 540, which will be described later, which is the second liquefied gas filled in the knockout drum 540, which will be described later, of the heat exchanger 520. ) To become a sub-cooling state, and the second liquefied gas in the supercooled state may be re-liquefied by cooling the boil-off gas supplied into the knockout drum 540 through the second line 502. It is.

The heater 530 may be provided on the first line 501 between the engine 30 and the heat exchanger 520, and is the same as the heaters 130, 230, and 440 of the first to second and fourth embodiments. Or, as a similar component, the description will be omitted to avoid duplication of the description.

Knockout drum 540 is provided on the second line 502 can be supplied to the boil-off gas generated in the second liquefied gas storage tank 40, is connected to the other end of the third line 503 heat exchanger A second liquefied gas that has been supercooled by 520 may be configured to be injected therein. In the present embodiment, instead of directly recovering the supercooled second liquefied gas to the second liquefied gas storage tank 40, by spraying the knockout drum 540, the thermal shock of the second liquefied gas storage tank 40 is performed. It is possible to prevent.

The second liquefied gas filled in the knockout drum 540 goes into a supercooled state through the heat exchanger 520, and the second liquefied gas in the supercooled state is supplied into the knockout drum 540 through the second line 502. The evaporated gas to be cooled can be re-liquefied.

The second liquefied gas inside the knockout drum 540 may be filled at the time of loading or using a cargo pump, an existing reliquefaction device, etc., and the present embodiment is not limited to this, and the inside of the knockout drum 540 by various means. Of course, the second liquefied gas can always be filled with a certain amount.

Since the second liquefied gas in the supercooled state injected into the knockout drum 540 re-liquefies the evaporated gas, the pressure inside the knockout drum 540 decreases, and the boiled gas generated in the second liquefied gas storage tank 40 A may be continuously drawn in as a free flow along the second line 502. For this reason, in the present embodiment, the knockout drum 540 also functions as an evaporation gas supply equipment of the reliquefaction apparatus, thereby eliminating the evaporation gas supply equipment to be installed in the reliquefaction apparatus including a blower, a compressor, and the like.

The second pump 550 may be provided on the second line 502 between the knockout drum 540 and the second liquefied gas storage tank 40, and the second liquefied gas discharged from the knockout drum 540 may be provided. It may be pressurized to recover to the second liquefied gas storage tank 40 through the second line 502 or to be supplied to the heat exchanger 520 through the third line 503.

The second pump 550 may adjust the flow rate or pressure of the second liquefied gas supplied to the heat exchanger 520.

The water level control valve 560 continues to increase the water level due to the re-liquefaction of the boil-off gas supplied from the second liquefied gas storage tank 40 in the second liquefied gas inside the knockout drum 540, inside the knockout drum 540 The second liquefied gas may be further provided at the rear end of the second pump 550 to maintain a constant level.

The water level control valve 560 is a second line 502 between the second pump 540 and the second liquefied gas storage tank 40, specifically, the second pump 540 and the second liquefied gas storage tank 40 ) May be provided on the second line 502 downstream of the connection point of the third line 503 connected between them.

The water level control valve 560 is opened when the level of the second liquefied gas inside the knockout drum 540 becomes higher than a certain level, and the second liquefied gas is stored in the second liquefied gas storage tank 40 through the second line 502. It can be recovered, and if it is lower than a certain water level, it is closed to control the second liquefied gas to be supplied to the heat exchanger 520 through the third line 503.

7 is a conceptual diagram of a liquefied gas treatment system according to a sixth embodiment of the present invention.

As illustrated in FIG. 7, the liquefied gas treatment system 600 according to the sixth embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 610, the heat exchanger 620, It includes a heater 630, a knockout drum 640, a second pump 650, a water level control valve 660, a compressor 670.

In the above, the first pump 610, the heat exchanger 620, the heater 630, the compressor 670 may be components of the fuel supply device, the heat exchanger 620, the knockout drum 640, the second The pump 650 and the water level control valve 660 may be components of the reliquefaction device, and the heat exchanger 620 commonly used may be configured to link the fuel supply device and the reliquefaction device.

The above-described components may be provided on the first line 601, the second line 602, the third line 603, and the fourth line 604.

Specifically, the first line 601 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A first pump 610, a heat exchanger 620, and a heater 630 may be provided on the first line 601.

The second line 602 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end may be connected to the interior of the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. On the second line 602, a knockout drum 640, a second pump 650, and a water level control valve 660 may be provided.

The third line 603 has one end connected to the second line 602 between the second liquefied gas storage tank 40 and the second pump 650 to be described later, and the other end to the knockout drum 640 to be described later. It may be connected, and may be configured to re-liquefy the boil-off gas generated inside the second liquefied gas storage tank 40. A heat exchanger 620 may be provided on the third line 603.

The fourth line 604 has one end connected to the upper portion of the first liquefied gas storage tank 20, the other end may be connected to the interior of the first liquefied gas storage tank 20, and the first liquefied gas storage tank ( 20) may be configured to re-liquefy the boil-off gas generated inside. A compressor 670 and a heat exchanger 620 may be provided on the fourth line 604.

The first pump 610 may be provided on the first line 601 between the first liquefied gas storage tank 20 and the heat exchanger 620, which will be described later, or the same as the pump 510 of the fifth embodiment or As a similar component, the description will be omitted here to avoid duplication of the description.

The heat exchanger 620 may be provided on the first line 601, the third line 603, and the fourth line 604, LNG- when the first liquefied gas is LNG and the second liquefied gas is LPG It may be an LPG-BOG (LNG) heat exchanger. That is, the heat exchanger 620 is composed of a three-stream (3-stream), which is a large amount of evaporation gas generated in the first liquefied gas storage tank 20 and the second liquefied gas storage tank 40 inside It may be suitable when the amount of evaporated gas generated is small.

Specifically, the heat exchanger 620 may be located between the first pump 610 and the heater 630 to be described later in the first line 601, and in the fourth line 604, the first liquefied gas storage tank ( 20) and the compressor 670, and may be located in a part of the third line 603.

In the heat exchanger 620, the first liquefied gas having a relatively low boiling point supplied from the first liquefied gas storage tank 20 to the engine 30 through the first line 601 and the knockout drum 640 to be described later Generated from the second liquefied gas having a relatively high boiling point filled therein, and a first liquefied gas having a relatively high boiling point stored inside the first liquefied gas storage tank 20, the fourth line 602 is re-liquefied. The first liquefied gas supplied to the engine 30 via the heater 630, which will be described later, is exchanged through the volatile gas circulating through the evaporation gas generated from the first liquefied gas and the second liquefied gas. Evaporation gas generated by the second liquefied gas storage tank 40 enables heat energy to be reduced when the engine 30 is heated to a temperature required by the engine 30 by obtaining heat by each heat of gas. Re-liquefaction in knockout drum 640 to be described later By, it is possible to increase the efficiency of re-liquefaction of the evaporated gas generated in the second liquefied gas storage tank 40, the evaporated gas generated in the first liquefied gas storage tank 20 by the cold heat of the first liquefied gas By re-liquefying, it is possible to increase the re-liquefaction efficiency of the evaporated gas generated inside the first liquefied gas storage tank 20.

The boil-off gas generated in the second liquefied gas storage tank 40 may be re-liquefied in the knockout drum 640, which will be described later, which is the second liquefied gas filled in the knockout drum 640, which will be described later, of the heat exchanger 620 ) To become a sub-cooling state, and the second liquefied gas in the super-cooled state may be re-liquefied by cooling the boil-off gas supplied into the knockout drum 640 through the second line 602. It is.

The heater 630 may be provided on the first line 601 between the engine 30 and the heat exchanger 620, and is the same or similar component to the heater 530 of the fifth embodiment. In order to avoid the description will be omitted.

Knockout drum 640 is provided on the second line 602 can be supplied with the boil-off gas generated in the second liquefied gas storage tank 40, is connected to the other end of the third line 603 heat exchanger It may be configured to inject the second liquefied gas that has been supercooled by 620 therein, and the same or similar components to the knockout drum 540 of the fifth embodiment will be described herein to avoid duplication of description. It will be omitted.

The second pump 650 may be provided on the second line 102 between the knockout drum 640 and the second liquefied gas storage tank 40, the same as the second pump 550 of the fifth embodiment or As a similar component, the description will be omitted here to avoid duplication of the description.

The water level control valve 660 may be provided at the rear end of the second pump 650 to maintain a constant level of the second liquefied gas inside the knockout drum 640, and the water level control valve 560 of the fifth embodiment As the same or similar components, the description will be omitted here to avoid duplication of the description.

The compressor 670 may be provided on the fourth line 604 between the first liquefied gas storage tank 20 and the heat exchanger 620, and is generated and discharged inside the first liquefied gas storage tank 20 Pressurized boil-off gas can be supplied to the heat exchanger (620).

8 is a conceptual diagram of a liquefied gas treatment system according to a seventh embodiment of the present invention.

8, the liquefied gas treatment system 700 according to the seventh embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 710, the knockout drum 720, It includes a heater 730, a second pump 740, a water level control valve 750.

In the above, the first pump 710, the knockout drum 720, the heater 730 may be components of the fuel supply device, the knockout drum 720, the second pump 740, the water level control valve 750 May be a component of the reliquefaction device, and the knockout drum 720 commonly used may be a structure in which the fuel supply device and the reliquefaction device are connected.

The above-described components may be provided on the first line 701, the second line 702, and the third line 703.

Specifically, the first line 701 may be connected from the first liquefied gas storage tank 20 to the engine 30, and heat the first liquefied gas stored in the first liquefied gas storage tank 20 to heat the engine 30 ). A first pump 710, a knockout drum 720, and a heater 730 may be provided on the first line 701.

The second line 702 has one end connected to the upper portion of the second liquefied gas storage tank 40, the other end may be connected to the interior of the second liquefied gas storage tank 40, and the second liquefied gas storage tank ( 40) may be configured to re-liquefy the boil-off gas generated inside. A knockout drum 720, a second pump 740, and a water level control valve 750 may be provided on the second line 702.

The third line 703 has one end connected to the second line 702 between the second liquefied gas storage tank 40 and the second pump 740 to be described later, and the other end to the knockout drum 720 to be described later. It may be connected, and may be configured to re-liquefy the boil-off gas generated inside the second liquefied gas storage tank 40.

The first pump 710 may be provided on the first line 701 between the first liquefied gas storage tank 20 and the knockout drum 720, which will be described later, or the same as the pump 510 of the fifth embodiment or As a similar component, the description will be omitted here to avoid duplication of the description.

The knockout drum 720 is provided on the first line 701 and the second line 702, and the second liquefied gas storage tank 40 through the second line 701 while the first line 701 penetrates the inside. The evaporation gas generated therein may be supplied, and may be configured to be connected to the other end of the third line 703 to inject the second liquefied gas that has become supercooled. In the present embodiment, instead of directly recovering the supercooled second liquefied gas to the second liquefied gas storage tank 40, by spraying the knockout drum 720, the thermal shock of the second liquefied gas storage tank 40 is performed. It is possible to prevent.

The first line 701 penetrating the inside of the knockout drum 720 may have various forms such as a “U” tube or a straight tube, and so on. The knockout drum 720 may function as an LNG-LPG heat exchanger when the first liquefied gas is LNG and the second liquefied gas is LPG.

The second liquefied gas filled in the knockout drum 720 is circulated through the third line 703 by a second pump 740 to be described later provided in the second line 702, and the second liquefied gas circulated As it is injected into the first line 701 of various types through which the first liquefied gas flows through the inside of the knockout drum 720, it is heat exchanged with the first liquefied gas to become a supercooled state, and the second liquefied gas in the supercooled state is second By cooling the boil-off gas of the second liquefied gas supplied into the knockout drum 720 through the line 702 to be re-liquefied, the efficiency of re-liquefying the boil-off gas generated in the second liquefied gas storage tank 40 is increased. At this time, the first liquefied gas is the boil-out drum 720, the second liquefied gas and / or the second liquefied gas storage tank 40 in the supercooled state injected into the knock-out drum 720, the boil-off gas supplied into the knock-out drum 720 By heat exchange with the engine through the heater 530 to be described later ( The first liquefied gas supplied to 30) obtains heat by the heat of the boil-off gas generated from the second liquefied gas to reduce thermal energy when heating the heater 530 to a temperature required by the engine 30. .

The second liquefied gas inside the knockout drum 720 may be filled at the time of loading or using a cargo pump, an existing reliquefaction device, etc., and this embodiment is not limited thereto, and the inside of the knockout drum 720 by various means. Of course, the second liquefied gas can always be filled with a certain amount.

Since the second liquefied gas in the supercooled state injected into the knockout drum 720 re-liquefies the evaporated gas, the pressure inside the knockout drum 720 decreases, and the boiled gas generated in the second liquefied gas storage tank 40 A may be continuously drawn in as a free flow along the second line 702. For this reason, in the present embodiment, the knockout drum 720 functions as an evaporation gas supply equipment of the reliquefaction apparatus, thereby eliminating the evaporation gas supply equipment to be installed in the reliquefaction apparatus including a blower and a compressor.

The heater 730 may be provided on the first line 701 between the engine 30 and the knockout drum 720, and the same or similar components as the heater 530 of the fifth embodiment are described here, so that overlapping descriptions are made. In order to avoid the description will be omitted.

The second pump 740 may be provided on the second line 702 between the knockout drum 720 and the second liquefied gas storage tank 40, the same or similar to the knockout drum 540 of the fifth embodiment As a component, the description will be omitted here to avoid duplication of the description.

The water level control valve 750 continues to increase the water level due to the re-liquefaction of the boil-off gas supplied from the second liquefied gas storage tank 40 in the second liquefied gas inside the knockout drum 720, inside the knockout drum 720 The second liquefied gas may be further provided at the rear end of the second pump 740 to maintain a constant level.

The water level control valve 750 includes a second line 702 between the second pump 740 and the second liquefied gas storage tank 40, specifically, the second pump 740 and the second liquefied gas storage tank 40 ) May be provided on the second line 702 downstream of the connection point of the third line 703.

The water level control valve 750 is opened when the level of the second liquefied gas inside the knockout drum 720 is higher than a certain level, and the second liquefied gas is stored in the second liquefied gas storage tank 40 through the second line 702. It can be recovered, and if it is lower than a certain water level, it is closed to control the second liquefied gas to be supplied to the knockout drum 720 through the third line 703.

9 is a conceptual diagram of a liquefied gas treatment system according to an eighth embodiment of the present invention.

9, the liquefied gas processing system 800 according to the eighth embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 810, a pair of knockout drums ( 820a, 820b), a heater 830, a pair of second pumps 840a, 840b, and a pair of water level control valves 850a, 850b.

In the above, the first pump 810, a pair of knockout drums 820a, 820b, and a heater 830 may be components of a fuel supply device, a pair of knockout drums 820a, 820b, a pair The second pumps 840a, 840b, and a pair of water level control valves 850a, 850b may be components of a reliquefaction device, and a pair of knockout drums 820a, 820b commonly used are provided with a fuel supply device. It may be configured to link the reliquefaction device.

The above-described components may be provided on the first line 801, the pair of second lines 802a, 802b, and the pair of third lines 803a, 803b. The first line 801 is the same or similar to the first line 701 of the seventh embodiment, and each of the pair of second lines 802a and 802b is the same or similar to the second line 702 of the seventh embodiment In addition, each of the pair of third lines 803a and 803b is the same or similar component to the third line 703 of the seventh embodiment, and thus description is omitted to avoid duplication of the description.

The liquefied gas processing system 800 according to the eighth embodiment of the present invention is compared to the first pump 810 and the heater 830 in contrast to the liquefied gas processing system 700 according to the seventh embodiment of the present invention described above. The reliquefaction device configured in may be different. That is, the liquefaction device of the liquefied gas treatment system 700 according to the seventh embodiment is composed of a knockout drum 720, a second pump 740, and a water level control valve 750, while the liquefaction according to the eighth embodiment The re-liquefaction device of the gas treatment system 800 is composed of a pair of knockout drums 820a and 820b, a pair of second pumps 840a and 840b, and a pair of level control valves 850a and 850b.

However, the reliquefaction device of the liquefied gas treatment system 800 according to the eighth embodiment is one re-liquefaction with one knockout drum 820a, one second pump 840a, and one level control valve 850a. Constituting the device, the other knockout drum (820b), another second pump (840b), the other water level control valve (850b) to form another re-liquefaction device, one re-liquefaction device and the other The re-liquefaction device is disposed in series between the first pump 810 and the heater 830 and may be configured identically.

A pair of knockout drums 820a and 820b, a pair of second pumps 840a and 840b, and a pair of water level control valves 850a and 850b, each of which forms one reliquefaction device and another reliquefaction device The re-liquefaction device of the liquefied gas treatment system 700 according to the seventh embodiment is the same or similar component to each of the knockout drum 720, the second pump 740, and the water level control valve 750. In order to avoid, the description will be omitted.

Each of the first pump 810 and the heater 830 of the present embodiment is also the same or similar component to the first pump 710 and the heater 730 of the seventh embodiment, and thus, the description will be omitted to avoid duplication of description. do.

The liquefied gas treatment system 800 according to the eighth embodiment of the present invention is to install a re-liquefaction device configured between the first pump 810 and the heater 830 in multiple stages, wherein a plurality of second liquefaction The type of second liquefied gas stored in the gas storage tank 40 may be different, and a reliquefaction device may be installed for each of the plurality of second liquefied gas storage tanks 40.

If the type of the second liquefied gas is different, the boiling point of the second liquefied gas stored in the first second liquefied gas storage tank 40 is the lowest, and the second and third is stored in the second liquefied gas storage tank 40 It may be advantageous for the second liquefied gas to have a higher boiling point to re-liquefy the boil-off gas generated from the second liquefied gas stored in different types.

For example, in a plurality of second liquefied gas storage tanks 40, ethane (C ₂ H ₆ ) having a boiling point of -89.0 ° C. is stored in the first second liquefied gas storage tank 40, and the second second Propane (C ₃ H ₈ ) having a boiling point of -42 ° C is stored in the liquefied gas storage tank 40, and butane (C ₄ H ₁₀ ) having a boiling point of -0.5 ° C in a third second liquefied gas storage tank 40. When this is stored, it is possible to re-liquefy the evaporation gas by installing the re-liquefaction device in multiple stages as in the present embodiment.

10 is a conceptual diagram of a liquefied gas treatment system according to a ninth embodiment of the present invention.

10, the liquefied gas treatment system 900 according to the ninth embodiment of the present invention may be provided on the liquefied gas carrier 1, the first pump 910, the re-condenser 920, a knockout drum 930, a heater 940, a second pump 950, a water level control valve 960, and a compressor 970.

In the above, the first pump 910, the re-condenser 920, the knockout drum 930, the heater 940 may be components of the fuel supply device, the knockout drum 930, the second pump 950, The water level control valve 960 may be components of the reliquefaction device, and the knockout drum 930 commonly used may be configured to link the fuel supply device and the reliquefaction device.

The above-described components may be provided on the first line 901, the second line 902, the third line 903, and the fourth line 904.

In the ninth embodiment of the present invention, the rest of the components 901 and 902 except for the recondenser 920 provided on the first line 901 and the compressor 970 provided on the fourth line 904 , 903, 910, 930, 940, 950, 960, each component 701, 702, 703, 710, 720, 730, 740 in the liquefied gas treatment system 700 of the seventh embodiment of the present invention to be described above , 750), the description will be omitted in order to avoid duplication of the description, and only the components different from the seventh embodiment of the present invention and parts different from it will be described.

The re-condenser 920 may be provided on the first line 901 between the first pump 910 and the knockout drum 930. The re-condenser 920 may be of an in-line type, and may be configured in various forms other than the in-line type.

The compressor 970 may be provided on the fourth line 904 and pressurize the boil-off gas generated inside the first liquefied gas storage tank 20 to supply it to the re-condenser. Here, the fourth line 904 may have one end connected to the upper portion of the first liquefied gas storage tank 20 and the other end connected to the recondenser 920.

In the above, the re-condenser 920 re-liquefies the evaporation gas of the first liquefied gas supplied by the compressor 970 to be used as fuel for the engine 30. The first liquefied gas discharged from the first liquefied gas storage tank 20 may lose some of the cold heat in the process of re-liquefying the evaporated gas upstream of the knockout drum 930.

The present embodiment including the re-condenser 920 and the compressor 970 is a large amount of evaporation gas generated in the first liquefied gas storage tank 20 and the second liquefied gas storage tank 40 It may be suitable when the amount of evaporation gas is small.

The present invention is not limited to the first to ninth embodiments described above, and a combination of the first to ninth embodiments or a combination of at least one of the first to ninth embodiments and a known technology It can be included as another embodiment.

As described above, the present embodiment is configured such that the fuel supply device and the reliquefaction device are connected, and evaporation generated in the second liquefied gas storage tank 40 using the first liquefied gas stored in the first liquefied gas storage tank 20 It is possible to improve the reliquefaction efficiency of the gas, thereby simplifying the components of the reliquefaction apparatus and reducing the energy consumption and system construction cost of the reliquefaction apparatus.

In addition, in the present embodiment, the first liquefied gas supplied from the first liquefied gas storage tank 20 to the engine 30 is configured to be connected to the fuel supply device and the reliquefaction device, so that the second liquefied gas storage tank 40 Heat exchanged with the boil-off gas generated in the engine 30, the first liquefied gas to be used as fuel for the engine 30 can easily obtain the amount of heat required for vaporization from the boil-off gas, improving the energy efficiency of LNG fuel supplied to the engine 30 I can do it.

In the above, the present invention has been described based on the embodiments of the present invention, but this is merely an example and does not limit the present invention, and those skilled in the art to which the present invention pertains will not depart from the essential technical content of the present embodiment. It will be appreciated that various combinations or variations and applications not illustrated in the examples are possible in the scope. Accordingly, technical contents related to modifications and applications that can be easily derived from the embodiments of the present invention should be interpreted as being included in the present invention.

1: Liquefied gas carrier 10: Hull
20: first liquefied gas storage tank 30: engine
40: second liquefied gas storage tank 100 to 900: liquefied gas treatment system
110, 160, 210, 240, 310, 410, 510, 550, 610, 650, 710, 740, 810, 840a,
840b, 910, 950: pump
120, 220, 320, 420, 520, 620: heat exchanger
130, 230, 440, 530, 630, 730, 830, 940: heater
140: blower 150, 250, 340, 460: separator
170, 260, 350: reliquefaction unit 180: temperature control valve
270: injection nozzle 330, 450, 670, 970: compressor
430: buffer tank
540, 640, 720, 820a, 820b, 930: knockout drum
560. 660, 750, 850a, 850b, 960: water level control valve
920: recondenser

Claims (9)

A knockout drum in which the second evaporation gas generated in the second liquefied gas storage tank is supplied and the second liquefied gas is filled therein; And
And a heat exchanger for exchanging the second liquefied gas filled in the knockout drum with a first liquefied gas supplied from a first liquefied gas storage tank to a consumer.
The second liquefied gas is in a supercooled state in the heat exchanger, and the second evaporation gas is re-liquefied by injecting the second liquefied gas in the knockout drum into the liquefied gas processing system. According to claim 1,
The liquefied gas processing system, characterized in that the first liquefied gas is LNG, the second liquefied gas is LPG, and the heat exchanger is an LNG-LPG heat exchanger. According to claim 1,
A fuel supply device is provided in a first line connected from the first liquefied gas storage tank to the demand destination,
The fuel supply device,
The heat exchanger provided on the first line;
A first pump provided on the first line between the first liquefied gas storage tank and the heat exchanger to pressurize the first liquefied gas; And
And a heater provided on the first line between the heat exchanger and the customer, and heating the first liquefied gas to a temperature required by the customer. According to claim 3, The fuel supply device,
A liquefied gas treatment system further comprising a compressor provided on a fourth line of which one end is connected to the upper portion of the first liquefied gas storage tank and the other end is connected to the interior of the first liquefied gas storage tank. . The method of claim 4, wherein the heat exchanger,
The first liquefied gas that is provided on the fourth line between the compressor and the first liquefied gas storage tank, and supplies the second liquefied gas filled in the knockout drum from the first liquefied gas storage tank to the customer. It is composed of a 3-stream heat-exchanging with, and also exchanging heat with the first evaporation gas generated in the first liquefied gas storage tank,
The compressor,
Liquefied gas, which is provided on the fourth line between the first liquefied gas storage tank and the heat exchanger, and pressurizes the first evaporation gas generated in the first liquefied gas storage tank and supplies it to the heat exchanger. Processing system. According to claim 1,
A second line having one end connected to the upper portion of the second liquefied gas storage tank, the other end connected to the interior of the second liquefied gas storage tank, and one end connected to the second line, and the other end to the knockout A third line connected to the drum is provided with a reliquefaction device,
The reliquefaction device,
The knockout drum provided on the second line;
The heat exchanger provided on the third line;
The knockout drum and the second liquefied gas storage tank are provided on the second line, and the second liquefied gas discharged from the knockout drum is recovered through the second line to the second liquefied gas storage tank or the And a second pump pressurized to supply the heat exchanger through a third line. The method of claim 6, wherein the re-liquefaction device,
Further comprising a water level control valve provided on the second line downstream of the connection point of the third line connected between the second pump and the second liquefied gas storage tank,
The water level control valve,
When the level of the second liquefied gas inside the knockout drum is higher than a certain level, it is opened to recover the second liquefied gas to the second liquefied gas storage tank through the second line, and closed when it is lower than a certain level And the second liquefied gas is controlled to be supplied to the heat exchanger through the third line. According to claim 6, The knockout drum,
The second liquefied gas sprayed therein reduces the internal pressure by re-liquefying the second evaporation gas, so that the second evaporation gas generated in the second liquefied gas storage tank connects the second line. Accordingly, by being continuously introduced into the natural flow, the liquefied gas treatment system characterized in that it also functions as an evaporation gas supply equipment. A liquefied gas carrier, characterized in that the liquefied gas treatment system according to any one of claims 1 to 8 is provided.

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