KR101613373B1 - Vaporization Apparatus for Liquefied Natural Gas - Google Patents

Abstract

The present invention relates to a vaporization apparatus of a liquefied natural gas, which can perform smooth delivery of the natural gas in in-between seasons or in winter season and can perform stable natural gas delivery without a defrost driving, by preventing low temperature delivery in the in-between seasons or winter season by heating LNG or NG discharged from an ambient air vaporizer by an auxiliary heater part, by including: an LNG storage tank to store the liquefied natural gas; a plurality of ambient air vaporizers which is supplied with the LNG from the LNG storage tank and vaporizes the LNG; a main supply pipe part which is connected to the LNG storage tank and comprises an LNG pump; a branch supply pipe part which is branched from a main supply pipe plurally and is connected to the plurality of ambient air vaporizers and supplies the LNG in the LNG storage tank to the ambient air vaporizer; a plurality of natural gas discharge pipe parts which is connected to the ambient air vaporizer respectively; a natural gas header part connected to the plurality of natural gas discharge pipe parts; and a plurality of auxiliary heater parts which is comprised in each of the plurality of natural gas discharge pipe parts.

Description

[0001] The present invention relates to a vaporization apparatus for liquefied natural gas,

The present invention relates to a vaporizing apparatus for liquefied natural gas, and more particularly, to a vaporizing apparatus for liquefied natural gas which prevents generation of low temperature discharge of natural gas when an atmospheric vaporizer is used at a natural gas production base.

Generally, natural gas (NG) is gradually being used as a cleaner fossil fuel than coal or petroleum. In general, natural gas is a liquefied natural gas (LNG) Is transported.

The volume of LNG occupies about 1/600 of the volume of natural gas in the same amount of gas, so it is possible to transport natural gas by liquefying it more economically.

In Korea, most of the natural gas is imported, imported from importing countries using large LNG carriers, stored in a large storage facility, that is, LNG storage tank, and vaporized through a vaporizer, And is supplied to each gas supply source. Then, natural gas is supplied from each gas supply station to each use place.

The LNG is vaporized by raising the temperature of the LNG to above the boiling point of the LNG at a predetermined pressure using an atmospheric vaporizer or a vaporized vaporizer.

However, in the case of an apparatus for vaporizing a liquefied natural gas using an atmospheric vaporizer, there is a problem that a low-temperature discharge occurs in the early and late winter periods, and thus the discharge amount is reduced.

The prior art related to the present invention is disclosed in Korean Patent Laid-Open Publication No. 2009-0113312 entitled " Ambient Air Evaporator ", wherein the " ambient air evaporator " is a device for regenerating LNG using ambient air from a storage device, Is used as the defrosting medium and is supplied back to the NG main pipe at the position upstream or downstream of the evaporator after defrosting, or the process is performed in a state in which the reliability of the regeneration itself is low and there is no auxiliary power facility for mechanically recirculating There is a problem that recirculation from the downstream to the upstream is impossible.

It is an object of the present invention to provide a vaporizing apparatus for liquefied natural gas that prevents low-temperature delivery during a snowy or winter season.

The present invention provides a LNG storage tank for storing LNG;

A plurality of atmospheric vaporizers for receiving and vaporizing LNG from the LNG storage tank;

A main supply pipe connected to the LNG storage tank and having an LNG pump;

A branch supply pipe part branched from the main supply pipe part and connected to the plurality of standby type vaporizers to supply the LNG in the LNG storage tank to the atmospheric vaporizer;

A plurality of natural gas discharge pipe portions respectively connected to the discharge ports of the atmospheric vaporizer;

A natural gas header portion to which a plurality of the natural gas discharge pipe portions are connected; And

And a plurality of auxiliary heater portions provided respectively in the plurality of natural gas discharge pipe portions.

In the present invention, the auxiliary heater portion may include an auxiliary heating passage through which the LNG or NG discharged from the atmospheric vaporizer moves in the heater main body, an auxiliary heating fluid which is filled in the heater main body and passes through the auxiliary heating passage through heat exchange, And a trim heater for heating the fluid passing through the auxiliary heating passage through heat exchange between the auxiliary heating medium and the fluid passing through the auxiliary heating passage.

In the present invention, the auxiliary heater unit uses a combustion type carburetor connected to the natural gas discharge pipe.

In the present invention, the natural gas discharge pipe portion may include: a first gas discharge pipe connecting the atmospheric vaporizer and the combustion vaporizer; And a second gas discharge pipe connected to an outlet of the combustion type carburetor.

The apparatus for vaporizing liquefied natural gas according to the present invention further comprises a boost pump provided in the branch supply pipe section.

The apparatus for vaporizing liquefied natural gas according to the present invention further includes an air suction pipe portion for sucking the air drawn through the air fan and the air fan into the heating flow path for heating the vaporization medium fluid in the combustion type vaporizer.

The apparatus for vaporizing liquefied natural gas according to the present invention comprises: an auxiliary branch supply pipe portion branched from the main supply pipe portion and connected to the first gas discharge pipe; A first flow path opening / closing valve provided in the branch supply pipe portion; A second flow path opening / closing valve provided in the auxiliary branch pipe; And a vaporization operation controller connected to the first flow path opening / closing valve and the second flow path opening / closing valve according to the temperature of the atmosphere.

The apparatus for vaporizing liquefied natural gas according to the present invention further includes a third flow path opening / closing valve provided between the atmospheric vaporizer and the sub-branch portion at the first gas discharge pipe.

In the present invention, the vaporization operation control unit may suck air into the first flow path opening / closing valve, the second flow path opening / closing valve, the third flow path opening / closing valve, the air fan, the boost pump, the LNG pump, And a temperature measuring unit connected to the burner that heats the air in the heating channel of the combustion type carburetor and detects the temperature of the atmospheric air, and controls each operation according to the atmospheric temperature condition.

In the present invention, the vaporization operation control unit closes the flow path of the branch supply pipe portion with the first flow path opening / closing valve and opens the second flow path opening / closing valve to connect the LNG of the LNG storage tank to the auxiliary branch Is supplied directly to the combustion type carburetor through a pipe portion and is vaporized by the combustion type carburetor.

In the present invention, when the atmospheric temperature is 18 ° C or higher, the vaporization operation control unit opens the flow path of the branch supply pipe with the first flow path opening / closing valve and closes the second flow path opening / closing valve to connect the LNG of the LNG storage tank to the branch supply pipe To the atmospheric vaporizer and is vaporized by the atmospheric vaporizer.

In the present invention, when the atmospheric temperature is less than 18 캜 and 0 캜 or more, the vaporization operation control unit opens the flow path of the branch supply pipe with the first flow path opening / closing valve and closes the second flow path opening / closing valve to return the LNG in the LNG storage tank And the gas is supplied to the atmospheric evaporator through the branch supply pipe to pass through the atmospheric vaporizer and the combustion vaporizer so that the gasification temperature is 0 ° C or more, and the vaporization operation control unit operates the air fan, In the vaporizer, the vaporized medium is sucked into the heating channel which heats.

In the present invention, the vaporization operation control unit operates the boost pump.

The present invention has the effect of preventing the low-temperature delivery during the snack or winter season so that the natural gas can be smoothly discharged even during the snort or winter season, and the stable natural gas discharge can be performed without operating the sea ice.

In addition, the present invention makes it possible to reliably deliver natural gas in the winter season or in the winter season by simple facilities, thereby simplifying the LNG vaporization facility and reducing the installation cost.

1 is a schematic view showing an example of a vaporizing apparatus for liquefied natural gas according to the present invention;
2 is a schematic view showing another example of the vaporizing apparatus for liquefied natural gas according to the present invention;
FIG. 3 is a graph showing the exit temperature of NG vaporized in an atmospheric vaporizer according to the operation time in a conventional apparatus for vaporizing liquefied natural gas using an atmospheric vaporizer
4 is a graph showing the maximum possible operating time of the atmospheric vaporizer according to relative humidity and wall temperature
5 to 7 are diagrams showing an example of operation according to the atmospheric temperature in the vaporizing apparatus for liquefied natural gas according to the present invention

The present invention will now be described in detail with reference to the accompanying drawings. Hereinafter, a repeated description, a known function that may obscure the gist of the present invention, and a detailed description of the configuration will be omitted. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

1, the apparatus for vaporizing liquefied natural gas according to the present invention comprises an LNG storage tank 10 for storing LNG, And a plurality of atmospheric vaporizers 20 for supplying and vaporizing LNG in the LNG storage tank 10.

The LNG storage tank 10 and the atmospheric vaporizer 20 are connected to the LNG storage tank 10 and include a main supply pipe 30 for discharging the LNG in the LNG storage tank 10, 30 and connected to a plurality of the atmospheric evaporators 20 through a branch supply pipe portion 40 connected to the plurality of atmospheric vaporizers 20. [ That is, the atmospheric vaporizer 20 has a branch supply pipe portion 40 connected to the inlet side, and the main supply pipe portion 30 connected to the branch supply pipe portion 40 and connected to the discharge port of the LNG storage tank 10 The LNG tank is supplied with LNG from the LNG tank.

The main supply pipe 30 is provided with an LNG pump 11 for transferring the LNG in the LNG storage tank 10 to the atmospheric vaporizer 20. That is, the LNG in the LNG storage tank 10 is supplied to the atmospheric evaporator 20 by the operation of the LNG pump 11, and the atmospheric evaporator 20 sucks the atmosphere into the main body and is moved inside The LNG is vaporized by NG through heat exchange between the LNG and the atmosphere, discharged through the natural gas discharge pipe portion 50, and transferred to the natural gas header portion 60.

The plurality of atmospheric vaporizers 20 are each provided with a natural gas discharge pipe portion 50 for transferring the NG gasified at the discharge port to the natural gas header portion 60.

Although not shown, the atmospheric vaporizer 20 has an inlet in the main body of the vaporizer main body connected to the branch supply pipe portion 40, an outlet connected to the natural gas exhaust pipe portion 50, And the LNG passing through the vaporizing flow path is vaporized by sucking the atmosphere into the vaporizer main body through heat exchange between the atmosphere and the vaporizing flow path. This is the same as the structure of the conventional standby type vaporizer 20, .

A plurality of the natural gas discharge pipe sections 50 provided in each of the plurality of standby type vaporizers 20 are connected to the outlet of the atmospheric type vaporizer 20 and the natural gas header section 60, 20 to the natural gas header portion 60. The natural gas header portion 60 has a plurality of natural gas inlet ports.

The natural gas header 60 is connected to a plurality of the atmospheric vaporizers 20 and collects the NG that has been vaporized in each of the atmospheric vaporizers 20 and sends it to each gas supply station via a metering facility.

The natural gas discharge pipe portion 50 is provided with an auxiliary heater portion 70 for heating NG vaporized in the atmospheric vaporizer 20 so that the natural gas is discharged from the atmospheric vaporizer 20 It is preferable to prevent LNG or NG discharged at a temperature lower than 0 占 폚 from being sent out at a low temperature.

The auxiliary heater unit 70 includes an auxiliary heating channel (not shown) in which LNG or NG discharged from the atmospheric vaporizer 20 moves into the heater body, an auxiliary heating channel (not shown) through which the auxiliary heating channel And a trim heater 71 for heating the fluid passing through the auxiliary heating passage through heat exchange between the auxiliary heating medium and the fluid passing through the auxiliary heating passage. do.

The trim heater 71 preferably has a structure for circulating the auxiliary heating medium fluid to maintain the auxiliary heating medium fluid at a predetermined temperature or higher.

2, the auxiliary heater unit 70 is a combustion gasifier 72 connected to the natural gas exhaust pipe 50, and the natural gas exhaust pipe unit 50 includes the natural gas exhaust pipe 50, A first gas discharge pipe 51 connecting the atmospheric vaporizer 20 and the combustion vaporizer 72 and a second gas discharge pipe 52 connected to the discharge port of the combustion gasifier 72. That is, the NG discharged from the combustion type vaporizer 72 is transferred to the natural gas header 60 through the second gas discharge pipe 52.

Although not shown, the combustion type carburetor 72 is filled with a vaporizing medium fluid inside the vaporizer main body, is connected to the natural gas exhaust pipe portion 50, passes through the vaporization medium fluid, and is discharged from the atmospheric vaporizer 20 A vaporization flow path through which the LNG or NG flows and a heating flow path for heating the vaporization medium are formed.

The combustion type carburetor 72 is configured to introduce air heated by a burner or the like into the heating flow path or to heat the air in the heating flow path by a burner or the like to pass the heating flow path, Temperature or more, that is, LNG or NG passing through the vaporizing flow path can be heated to 0 ° C or higher, and LNG or NG passing through the vaporizing flow path can be heated to 0 ° C or higher. This is the same as the structure of the normal combustion type carburetor 72, and a detailed description thereof is omitted.

The combustion type carburetor 72 prevents the NG from being sent out at a low temperature by regenerating and heating the low temperature LNG or NG discharged from the atmospheric vaporizer 20 at a temperature of 0 ° C or lower.

The apparatus for vaporizing liquefied natural gas according to the present invention is provided in the branched supply pipe portion 40 to prevent the pressure of the gas passing through the atmospheric vaporizer 20 and the combustion vaporizer 72 from being lowered And a boost pump (80) for boosting the exhaust gas.

The boost pump 80 serves to increase the pressure of the gas passing through the atmospheric vaporizer 20 and the combustion vaporizer 72.

The apparatus for vaporizing liquefied natural gas according to the present invention includes an air suction pipe portion 91 for sucking the air sucked through the air fan 90 and the air fan 90 into the heating channel of the combustion type carburetor 72 ).

The air fan 90 is operated when the atmospheric temperature is less than 18 ° C and 0 ° C or more to suck air into the heating channel to maintain the temperature of the vaporizing medium in the combustion vaporizer 72 .

When the atmospheric temperature is lower than 0 ° C, air heated by a burner or the like is introduced into the vaporization flow path, or air in the vaporization flow path is heated by a burner or the like to pass through the vaporization flow path, The temperature of the intermediate fluid is maintained to keep the temperature rise.

The apparatus for vaporizing liquefied natural gas according to the present invention comprises: an auxiliary branch pipe section (100) branched from the main supply pipe section (30) and connected to the first gas discharge pipe (51);

A first flow path opening / closing valve (110) provided in the branch supply pipe portion (40);

A second flow path opening / closing valve 120 provided in the auxiliary branch pipe portion 100; And

And a vaporization operation control unit 140 connected to the first and second flow path switching valves 110 and 120 according to the atmospheric temperature.

The air conditioner further includes a third flow path opening / closing valve (130) provided between the atmospheric vaporizer (20) and the auxiliary branch pipe portion (100) It is preferable to prevent the movement of LNG or NG passing through the evaporator 20. [

The auxiliary branch pipe portion 100 branches off from the main supply pipe portion 30 and passes LNG in the LNG storage tank 10 through the combustion type vaporizer 72 without passing through the atmospheric vaporizer 20, .

The vaporization operation control unit 140 controls the operation of the air pump 90, the boost pump 80, the LNG pump 11, a fan for sucking air into the atmospheric vaporizer 20, And a temperature measuring unit 141 connected to a burner or the like for heating the air in the heating channel and sensing the temperature of the atmosphere, and controls each operation according to an atmospheric temperature condition. 2 and 5 to 7, the vaporization operation control unit 140 is connected to only one line of the standby-type vaporizer 20, but it is also connected to another line of the standby-type vaporizer 20, Note that the connection line is omitted for simplicity.

3 is a graph of the outlet temperature of NG vaporized in the atmospheric vaporizer 20 according to the operating time in the apparatus for vaporizing liquefied natural gas using the conventional atmospheric vaporizer 20 from January to December Respectively.

3, the temperature of the natural gas passing through the atmospheric vaporizer 20 continuously decreases according to the operation time of the atmospheric vaporizer 20, and the outlet temperature of the NG gas An auxiliary heat source for heating the NG that has passed through the atmospheric vaporizer 20, that is, the heat supply by the auxiliary heater unit 70 is indispensable.

4, when the relative humidity is 62% and the wall surface temperature is -100 ° C, the maximum possible operating time is predicted according to the atmospheric temperature, and the operation is possible without thaw operation for several days in one operation. The bypass line of the unit 70 and the feedback line for the sea ice operation are unnecessary.

The process of vaporizing the LNG in the LNG storage tank 10 by the vaporization operation control unit 140 according to the atmospheric temperature condition is as follows.

5, the vaporization operation control unit 140 closes the flow path of the branch supply pipe portion 40 to the first flow path opening / closing valve 110 when the atmospheric temperature is lower than 0 ° C, Closing valve 120 and opening the LNG storage tank 10 through the auxiliary branch pipe 100 so as to open the second gas opening / (72) and vaporized by the combustion type carburetor (72).

At this time, fuel for operating the burner is supplied to the combustion type carburetor 72 to heat air in the heating passage by operating the burner, or air heated by the operation of the burner flows into the heating passage, Thereby raising the temperature of the vaporization medium in the combustion vaporizer 72. That is, the combustion type carburetor 72 can be independently operated independently of the atmospheric type vaporizer 20, and independently operated when the vaporization effect by the atmospheric type vaporizer 20 is insufficient, such as during the winter season, To prevent unnecessary energy consumption.

6, the LNG in the LNG storage tank 10 can be sufficiently vaporized to 0 ° C. or more by using the atmospheric vaporizer 20 only when the ambient temperature is 18 ° C. or higher. Therefore, the vaporization operation control unit 140 The flow path of the branch supply pipe portion 40 is opened by the first flow path opening and closing valve 110 and the flow path of the first gas discharge pipe 51 is opened by the third flow path opening and closing valve 130, The valve 120 is closed and the LNG of the LNG storage tank 10 is supplied to the atmospheric vaporizer 20 through the branch supply pipe portion 40 and is vaporized by the atmospheric vaporizer 20.

At this time, the vaporization operation control unit 140 activates the boost pump 80 to increase the pressure of the gas discharged from the atmospheric vaporizer 20 to communicate with the combustion type vaporizer 72, and the combustion gasifier The air fan 90 and the burner for heating the vaporization-mediating fluid in the heat exchanger 72 are deactivated.

7, when the atmospheric temperature is lower than 18 deg. C and equal to or higher than 0 deg. C, the vaporization operation control unit 140 opens the flow path of the branch supply pipe portion 40 to the first flow path opening / closing valve 110, The LNG storage tank 10 is opened by opening the flow path of the first gas discharge pipe 51 with the 3-way opening / closing valve 130 and closing the second flow path opening / closing valve 120 to connect the LNG storage tank 10 to the branch supply pipe portion 40 Is supplied to the atmospheric vaporizer (20) through the atmospheric vaporizer (20) and the combustion vaporizer (72) so that the vaporization temperature is 0 ° C or higher.

At this time, the vaporization operation control unit 140 operates the air fan 90 to suck and pass an atmosphere of 0 ° C or less below 18 ° C through the heating flow path of the combustion type carburetor 72, The temperature of the vaporization medium is heated to ensure that the temperature of NG that is finally vaporized and discharged is 0 DEG C or higher.

In other words, during the period of atmospheric temperature lower than 18 ° C and 0 ° C or higher, the discharge temperature of the NG gas can be 0 ° C or more without consuming any fuel through two vaporization processes using the ambient temperature.

The present invention prevents the low-temperature delivery in the early season or the winter season, so that the natural gas can be smoothly discharged even during the winter season or the winter season, and stable natural gas discharge can be performed without operating the sea ice.

In addition, the present invention makes it possible to reliably deliver natural gas in the early season or the winter season by simple facilities, thereby simplifying the LNG vaporization facility and reducing the installation cost.

The present invention prevents the low-temperature delivery in the early season or the winter season, so that the natural gas can be smoothly discharged even during the winter season or the winter season, and stable natural gas discharge can be performed without operating the sea ice.

In addition, the present invention makes it possible to reliably deliver natural gas in the early season or the winter season by simple facilities, thereby simplifying the LNG vaporization facility and reducing the installation cost.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the above teachings. will be.

10: LNG storage tank 20: atmospheric vaporizer
30: main supply pipe 11: LNG pump
40: branch supply pipe 50: natural gas discharge pipe
51: first gas discharge pipe 52: second gas discharge pipe
60: natural gas header part 70: auxiliary heater part
71: Trim heater 72: Combustion carburetor
80: Boost pump 90: Air fan
91: atmospheric air suction pipe part 100: auxiliary branch pipe part
110: first flow path opening / closing valve 120: second flow path opening / closing valve
130: third-flow opening / closing valve 140: vaporization-
141: Temperature measuring unit

Claims (13)

An LNG storage tank for storing LNG;
A plurality of atmospheric vaporizers for receiving and vaporizing LNG from the LNG storage tank;
A main supply pipe connected to the LNG storage tank and having an LNG pump;
A branch supply pipe part branched from the main supply pipe part and connected to the plurality of standby type vaporizers to supply the LNG in the LNG storage tank to the atmospheric vaporizer;
A plurality of natural gas discharge pipe portions respectively connected to the discharge ports of the atmospheric vaporizer;
A natural gas header portion to which a plurality of the natural gas discharge pipe portions are connected; And
And a plurality of auxiliary heater portions respectively provided in the plurality of natural gas discharge pipe portions,
The auxiliary heater is a combustion type carburetor connected to the natural gas exhaust pipe,
The natural gas discharge pipe portion
A first gas discharge pipe connecting the atmospheric vaporizer and the combustion vaporizer; And
And a second gas exhaust pipe connected to an exhaust port of the combustion type carburetor,
A boost pump provided in the branch supply pipe;
An air suction pipe unit for sucking the air sucked through the air fan and the air fan into the heating channel for heating the vaporization medium fluid in the combustion type carburetor;
An auxiliary branch pipe branching from the main supply pipe and connected to the first gas discharge pipe;
A first flow path opening / closing valve provided in the branch supply pipe portion;
A second flow path opening / closing valve provided in the auxiliary branch pipe; And
Further comprising a vaporization operation control unit connected to the first flow path opening / closing valve and the second flow path opening / closing valve according to an atmospheric temperature. delete delete delete delete delete delete The method according to claim 1,
Further comprising a third flow path opening / closing valve provided between the atmospheric vaporizer and the sub-branch portion of the first gas discharge pipe. The method of claim 8,
Wherein the vaporization operation control unit is configured to control the vaporization operation of the at least one of the first flow path switching valve, the second flow path opening / closing valve, the third flow path switching valve, the air fan, the boost pump, the LNG pump, And a temperature measuring unit connected to a burner that heats the air in the heating channel of the combustion type carburetor and detects the temperature of the atmosphere, and controls each operation according to an atmospheric temperature condition. The method of claim 9,
Wherein the vaporization operation control unit closes the flow path of the branch supply pipe with the first flow path opening and closing valve and opens the second flow path opening and closing valve to connect the LNG of the LNG storage tank through the auxiliary branch pipe And the gas is directly supplied to the combustion type carburetor and is vaporized by the combustion type vaporizer. The method of claim 9,
Wherein the vaporization operation control unit opens the flow path of the branch supply pipe portion to the first flow path opening and closing valve and closes the second flow path opening and closing valve to transfer the LNG of the LNG storage tank through the branch supply pipe portion Is supplied to an atmospheric vaporizer and is vaporized by the atmospheric vaporizer. The method of claim 9,
Wherein the vaporization operation control unit opens the flow path of the branch supply pipe portion with the first flow path opening / closing valve and closes the second flow path opening / closing valve to transfer the LNG in the LNG storage tank to the branch supply pipe portion Is supplied to the atmospheric vaporizer through the atmospheric vaporizer and the combustion vaporizer so that the vaporization temperature is 0 ° C or higher,
Wherein the vaporization operation control unit operates the air fan to suck air into the heating flow path for heating the vaporization medium fluid in the combustion type vaporizer. The method according to claim 11 or 12,
And the vaporization operation control unit operates the boost pump.

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