KR102454778B1 - A simple LNG refueling station that minimizes boil-off gas - Google Patents

Abstract

The present invention relates to a charging station for charging liquefied natural gas (LNG). The charging station includes: at least one dispenser (10) built by civil engineering at a location in which at least an LNG charge demand and safety are satisfied, and connected to an LNG tank of a vehicle to charge LNG; a protective fence (20) installed at a location spaced apart from the dispenser (10) by a predetermined distance, and providing a parking area (P) having a set area therein; a trailer (30) storing a large amount of LNG to be supplied to the dispenser (10), and towed to the parking area (P) and housed in isolation from the outside; a pump unit (40) installed in the parking area (P) or the trailer (30), and transporting the LNG stored in the trailer (30) to the dispenser (10); and a control center (50) installed at a location adjacent to the dispenser (10), and allowing a manager to manage the dispenser (10) or the pump unit (40) therein. Therefore, the present invention can replace a tank facility built to store LNG for a long period, with a LNG transport trailer, thereby having effects of minimizing costs for overall construction, and improving safety through free movement to another charging station in need of LNG as well as reducing boiloff gas produced from long-term storage.

Description

A simple LNG refueling station that minimizes boil-off gas

The present invention relates to a charging station that charges a liquefied natural gas (LNG) vehicle, and more particularly, by replacing a tank facility that is built to store LNG for a long time with a trailer that transports LNG, it is possible to minimize the overall construction cost. As it can be moved to other charging stations that require LNG at any time, it is possible to improve safety and reduce boil-off gas caused by long-term storage. It relates to a simple LNG refueling station that minimizes boil-off gas that can minimize the overall boil-off gas generated during charging or storage by configuring a recovery means for recharging the boil-off gas by converting it into liquefied gas.

Normally, liquefied natural gas (LNG) is an eco-friendly energy source that does not contain sulfur oxides 100%, dust 99%, nitrogen oxides 90%, SOx, and reduces carbon dioxide by 20%. It is expected to be the main energy source for

In the case of ships, with the IMO's 80% NOx reduction regulation taking effect in 2016, European countries are preempting the supply and technology development of new coastal ships operated with LNG as fuel.

In addition, most vehicles (tractors) used for towing containers use diesel fuel, but as they are considered one of the causes of fine dust, the number of cases of remodeling or releasing LNG for these vehicles is gradually increasing.

However, since the number of such LNG vehicles is extremely small compared to existing vehicles, it is expected that many difficulties will arise in recharging fuel because there are not enough charging stations (charging infrastructure) yet.

In addition, the existing LNG refueling station has a problem in that the cost of building the initial refueling station is aggravated because it is necessary to construct a tank lorry for LNG storage in a fixed manner through civil works.

Above all, as mentioned above, since the number of LNG vehicles is small, there is a high possibility that LNG must be stored for a long time in a tank lorry. Measures are also needed.

Meanwhile, as the amendment bill to the enforcement regulations of the City Gas Business Act came into effect, the definition and facility standards for the mobile LNG refueling business were prepared. In other words, in accordance with the policy to expand the use of LNG as a transportation fuel, it was allowed to charge LNG vehicles using a mobile tank lorry.

Republic of Korea Patent Publication No. 10-2011692 (Title of the invention: container mobile LNG supply facility)

The present invention has been proposed to solve the above problems, and by replacing the tank facility that is built to store LNG for a long time with a trailer that transports LNG, it is possible to minimize boil-off gas that can minimize the cost of overall construction. The purpose is to provide a simple LNG refueling station that minimizes boil-off gas.

In addition, the present invention has the purpose of reducing boil-off gas generated due to long-term storage as well as improving safety as it can be moved to other charging stations that require LNG at any time.

In addition, the present invention can minimize the overall BOG generated during charging or storage by configuring a recovery means for converting BOG generated from the trailer into liquefied gas and recharging it together with a pre-cooling means for cooling the pipeline through which LNG flows to a low temperature. The purpose is to provide a simple LNG refueling station that minimizes possible boil-off gas.

The present invention relates to a charging station for refueling liquefied natural gas (LNG), comprising: one or more dispensers constructed by civil engineering work at a location where at least the LNG refueling demand and safety are satisfied, and connected to an LNG tank of a vehicle to charge LNG; a protective fence installed at a location spaced apart from the dispenser by a predetermined distance and providing a parking area of a set area therein; a trailer in which a large amount of LNG to be supplied to the dispenser is stored, towed to the parking area and stored in isolation from the outside; a pump unit installed in the parking area or the trailer and transferring the LNG stored in the trailer to a dispenser; and a control center installed at a position adjacent to the dispenser, and in which a manager who manages the dispenser or the pump unit performs duties.

At this time, the trailer according to the present invention, H-type undercarriage frame having a set length and width; a suspension mounted together with a plurality of wheels at the lower end of the chassis frame and absorbing shocks generated from the ground; a manual or electric support leg disposed in front of the chassis frame to support it from the ground; a loading table disposed between the suspension and the supporting legs to accommodate auxiliary wheels or materials; an arc-shaped support frame mounted on the chassis frame, the support legs, and the top of the loading table; a cylindrical tank lorry mounted on the upper end of the support frame and storing a predetermined amount of LNG therein; It is characterized in that it is composed of; a kingpin that is mounted on the lower end of the front side of the tank lorry and connects the towing vehicle and articulation.

In addition, the tank lorry according to the present invention, a cylindrical outer cylinder mounted on the upper end of the support frame; Cylindrical inner cylinder mounted spaced apart from the inside of the outer cylinder at a predetermined distance; An arc-shaped roof frame that is spaced apart so that the upper end of the outer cylinder is wrapped and blocks heat transfer generated from sunlight to suppress evaporation gas; It is characterized in that it is composed of a; arc-shaped insulation frame that is spaced apart mounted on the inner surface of the outer cylinder in close contact with the support frame, and blocks heat transmitted from the floor to suppress boil-off gas.

In addition, the outer cylinder according to the present invention is formed of SS275 having a thickness of 9 mm or more, and the inner cylinder is formed of SUS304 having a thickness of 10 mm or more.

In addition, the outer cylinder and the inner cylinder according to the present invention are mounted at a distance of 240 mm or more from each other, and a vacuum of 1x10 ^-4 Torr or more is formed while filling the urethane foam between the outer / inner cylinder.

In addition, the outer cylinder and the insulating frame according to the present invention are mounted at a distance of 175 mm or more from each other, and a vacuum of 1x10 ^-4 Torr or more is formed while the pearlite powder is filled between the outer cylinder and the insulating frame.

In addition, the LNG charging station according to the present invention further comprises a pre-cooling means for cooling the pipe connected to the dispensing and the pump unit to a low temperature to suppress boil-off gas generated due to a temperature difference when charging the vehicle. .

In addition, the pre-cooling means according to the present invention may include: a nitrogen tank connected by a pipe between the dispensing unit and the pump unit and cooling the pipe to −130° C. or higher by discharging liquid nitrogen before charging LNG into the vehicle; a vacuum pump connected to the LNG discharge pipe of the dispensing and suctioning the cooled pipe in a vacuum to remove residual liquid nitrogen; and a plurality of check valves installed in each pipe connected between the dispensing unit and the pump unit and the nitrogen tank and the vacuum pump to block the reverse flow of liquid nitrogen.

In addition, the LNG refueling station according to the present invention, connected to the trailer, the boil-off gas generated in the upper layer is converted into liquefied gas and a recovery means for recharging it; characterized in that it further comprises.

In addition, the recovery means according to the present invention may include: a main heat exchanger connected to the trailer to receive boil-off gas, and liquefy the supplied boil-off gas to a low temperature; a compressor connected to the main heat exchanger to receive boil-off gas, compress the supplied boil-off gas into liquefied gas and return it to the main heat exchanger; an auxiliary tank receiving the main heat exchanger and the boil-off gas, and temporarily storing the supplied boil-off gas to be converted into liquefied gas; and an auxiliary heat exchanger connected to the trailer and the auxiliary tank, respectively, transferring the stored liquefied gas of the auxiliary tank to the main heat exchanger and supplying the liquefied gas of the main heat exchanger to the trailer.

In addition, the auxiliary tank according to the present invention is characterized in that the boil-off gas stored therein is mixed with the liquefied gas transferred to the main heat exchanger through the auxiliary heat exchanger.

In addition, the recovery means according to the present invention, each connected between the main heat exchanger and the compressor, the turbo expander having a pair of impellers synchronously rotating in the center together with the input/output ports divided on both sides; characterized in that it is further configured .

In addition, the turbo expander according to the present invention is characterized in that the liquefied gas returned from the compressor to the main heat exchanger generates a compressive force at the input/output port of the other side.

In addition, the turbo expander according to the present invention sucks and compresses boil-off gas from the main heat exchanger through the rotational force generated by the compressor, and mixes it with the liquefied gas transferred to the main heat exchanger through the auxiliary heat exchanger.

In addition, the recovery means according to the present invention, a cooler interposed for each line connected to the compressor, the turbo expander, and the main heat exchanger to cool the liquefied gas; characterized in that it is further configured.

The present invention has been proposed to solve the above problems, and by replacing the tank facility that is built to store LNG for a long time with a trailer that transports LNG, it is possible to minimize boil-off gas that can minimize the cost of overall construction. There is a remarkable effect that can minimize the boil-off gas.

In addition, the present invention has a special effect of reducing boil-off gas generated due to long-term storage as well as safety improvement as it can be moved to other charging stations that require LNG at any time.

In addition, the present invention can minimize the overall BOG generated during charging or storage by configuring a recovery means for converting BOG generated from the trailer into liquefied gas and recharging it together with a pre-cooling means for cooling the pipeline through which LNG flows to a low temperature. can have an effect.

In addition to the above-described effects, the specific effects of the present invention will be described together while describing specific details for carrying out the invention below.

1 is a perspective view of an LNG refueling station according to the present invention as a whole.
2 and 3 are perspective views independently showing a trailer according to the present invention.
4 is a cross-sectional view showing a trailer according to the present invention by cutting it.
5 is a schematic diagram showing an LNG refueling station to which the pre-cooling means according to the present invention is applied.
6 is a schematic diagram showing an LNG refueling station to which the recovery means according to the present invention is applied.
7 is a reference view showing the turbo expander of the recovery means according to the present invention by cutting it.

Hereinafter, various embodiments of the present document will be described with reference to the accompanying drawings. However, it is not intended to limit the technology described in this document to specific embodiments, and it should be understood that various modifications, equivalents, and/or alternatives of the embodiments of this document are included. In connection with the description of the drawings, like reference numerals may be used for like components.

In addition, expressions such as "first," "second," used in this document may modify various elements regardless of order and/or importance, and to distinguish one element from another element. It is used only and does not limit the corresponding components. For example, 'first part' and 'second part' may represent different parts regardless of order or importance. For example, without departing from the scope of the rights described in this document, the first component may be named as the second component, and similarly, the second component may also be renamed as the first component.

In addition, terms used in this document are used only to describe specific embodiments, and may not be intended to limit the scope of other embodiments. The singular expression may include the plural expression unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meanings as commonly understood by one of ordinary skill in the art described in this document. Among the terms used in this document, terms defined in a general dictionary may be interpreted with the same or similar meaning to the meaning in the context of the related art, and unless explicitly defined in this document, ideal or excessively formal meanings is not interpreted as In some cases, even terms defined in this document cannot be construed to exclude embodiments of the present document.

The present invention relates to a charging station for charging liquefied natural gas (LNG), and as shown in FIG. 1, a dispenser 10, a protective fence 20, a trailer 30, a pump unit 40, and a control station 50 are the main components. A simple LNG refueling station that minimizes boil-off gas.

First, as shown in FIG. 1 , the dispenser 10 according to the present invention is constructed in a position where at least the LNG charging demand and safety are satisfied by civil engineering work.

The dispenser 10 is configured with a nozzle connected to the LNG tank of the vehicle, and is connected to the pump unit 40 through a pipe to fill the LNG.

Here, the dispenser 10 is preferably constructed in two or more so that several vehicles can be charged at the same time.

And the protective fence 20 according to the present invention is installed at a location spaced apart from the dispenser 10 by a predetermined distance, as shown in FIG. 1 .

This protective fence 20 is to store the trailer 30, and provides a parking area (P) of a set area therein.

That is, the protective fence 20 is to isolate the trailer 30 warehousing from the outside, and can be configured as a building structure that completely blocks the outside in addition to the wire fence shown.

Of course, it can be constructed in the form of an underground bunker according to safety and cost without building it on the ground.

Subsequently, the trailer 30 according to the present invention stores a large amount of LNG to be supplied to the dispenser 10 as shown in FIG. 1 , and is towed to the parking area P by a towing vehicle and stored separately from the outside.

As shown in FIGS. 2 and 3 , the trailer 30 is largely a chassis frame 31 , a suspension 32 , a support leg 33 , a loading stand 34 , a support frame 35 , and a tank lorry 36 . , and a kingpin (37).

The chassis frame 31 is formed in an H-shape, and has a set length and width supporting the rear of the tank lorry 36 .

The suspension 32 is mounted together with a plurality of wheels at the lower end of the chassis frame 31 to absorb shocks generated from the ground.

It is preferable to configure the suspension 32 as a pneumatic control type capable of electronic control rather than a leaf spring.

The support legs 33 are disposed in front of the chassis frame 31 to support them horizontally from the ground.

This support leg 33 is made of a rack and pinion structure, it is preferable to configure the length can be changed automatically by manual or electric motor.

The loading table 34 is disposed between the suspension 32 and the support legs 33 to accommodate auxiliary wheels or materials.

The support frame 35 is formed in an arc shape that can be in close contact with the tank lorry 36 , and is mounted on the upper end of the chassis frame 31 , the support legs 33 , and the loading table 34 .

The tank lorry 36 is formed in a cylindrical shape to store LNG of a predetermined capacity therein, and is fixedly mounted on the upper end of the support frame 35 .

The kingpin 37 is mounted at the lower end of the front side of the tank lorry 36 to connect it to the towing vehicle and articulate it.

At this time, the tank lorry 36 is formed of a large cylindrical outer / inner cylinder (36a, 36b), a roof frame (36c) and a thermal insulation frame (36d) as shown in FIG.

The outer cylinder (36a) is fixedly mounted on the upper end of the support frame (34), and the inner cylinder (36b) is mounted at a distance of 240 mm or more by a baffle frame (not shown) inside the outer cylinder (36a).

Here, the outer cylinder (36a) is preferably formed of SS275 having a thickness of 9 mm or more, and the inner cylinder (36b) is formed of SUS304 having a thickness of 10 mm or more.

And a vacuum of 1x10-4 Torr or more is formed between the outer/inner cylinder (35a) and (35b) with the urethane foam having excellent thermal insulation properties.

The roof frame 36c is formed in an arc shape, and is spaced apart and mounted at a predetermined distance so that the upper end of the outer cylinder 36a is wrapped.

The roof frame 36c blocks heat transfer generated from sunlight to suppress boil-off gas of stored LNG.

The insulating frame (36d) is formed in an arc shape, and is spaced apart and mounted at a distance of 175 mm or more on the inner surface of the outer cylinder (36b) in close contact with the support frame (34).

Here, between the outer cylinder (36b) and the insulating frame (36d) is filled with pearlite powder and a vacuum of 1x10-4 Torr or more is formed.

That is, the heat insulation frame 36d blocks heat transferred from the ground, the chassis frame 31 and the support frame 35 to suppress boil-off gas of stored LNG.

Then, the pump unit 40 according to the present invention transfers the LNG stored in the trailer 30 to the dispenser 10 .

The pump unit 40 is independently installed in the parking area P as shown in FIG. 1 .

Of course, although not shown in a separate drawing, it may be integrally mounted on the rear side of the trailer 30 .

Finally, the control center 50 according to the present invention provides a space for the manager who manages the dispenser 10 to the pump unit 40 to perform work.

The control station 50 is installed in a position adjacent to the dispenser 10 as shown in FIG. 1 , but it is preferable to configure it as a container in consideration of cost and convenience.

Here, the control station 50 may establish an on-line system that interworks with an observer that detects seismic waves or a seismic observatory.

That is, the observer or system automatically and quickly stops the operation of the dispenser 10 or the pump unit 40 when an earthquake occurs to prevent a major accident.

Meanwhile, the LNG refueling station according to the present invention may further include a pre-cooling means 60 as shown in FIG. 5 .

That is, the pre-cooling means 60 cools the pipe connected to the dispense 10 and the pump unit 40 to a low temperature, thereby suppressing the boil-off gas generated due to a temperature difference when charging the vehicle.

The pre-cooling means 50 includes a nitrogen tank 61 , a vacuum pump 62 , and a plurality of check valves 63 .

The nitrogen tank 61 stores liquid nitrogen, and is connected by a pipe between the dispense 10 and the pump unit 40 .

That is, the nitrogen tank 61 discharges liquid nitrogen according to a signal before charging the LNG to the vehicle to cool the pipe between the dispense 10 and the pump unit 40 to −130° C. or higher.

The vacuum pump 62 is connected to the LNG discharge pipe of the dispensing 10 and sucks the cooled pipe in a vacuum to remove liquid nitrogen remaining in the pipe.

The check valve 63 is installed for each pipe connected between the dispense 10 and the pump unit 40 and the nitrogen tank 61 and the vacuum pump 62 to block the reverse flow of liquid nitrogen.

Since the pre-cooling means 60 uses safe nitrogen, it is possible to significantly lower the risk factor.

And by using liquid nitrogen with a low boiling point (-191℃ below zero), the time required for pre-cooling can be shortened.

Above all, since the price of nitrogen is relatively low, the cost of pre-cooling can be greatly reduced.

In addition, the LNG refueling station according to the present invention may further include a recovery means 70 as shown in FIG. 6 .

That is, the recovery means 70 converts the boil-off gas generated in the upper inner part of the tank lorry 36 into liquefied gas and recharges it.

The recovery means 70 includes a main heat exchanger 71 , a compressor 72 , an auxiliary tank 73 , and an auxiliary heat exchanger 74 .

The main heat exchanger 71 is a parallel flow type aluminum heat exchanger, and is connected to the tank lorry 36 , the compressor 72 , the auxiliary tank 73 , and the auxiliary heat exchanger 74 .

That is, the main heat exchanger 71 is connected to the tank lorry 36 to receive boil-off gas and to receive liquefied gas from the compressor 72 .

The main heat exchanger 71 liquefies the boil-off gas supplied through the liquefied gas introduced from the compressor 72 at a low temperature.

And the liquefied gas is recharged in the tank lorry 36 through the auxiliary heat exchanger 74 , and the boil-off gas is supplied to the auxiliary tank 73 .

The compressor 72 is connected to the main heat exchanger 71 to compress the boil-off gas into liquefied gas and returns it to the main heat exchanger 71 .

The auxiliary tank 73 receives the boil-off gas from the main heat exchanger 71 and provides a buffer space to convert the turbo expander 75 to be described later into liquefied gas.

That is, the liquefied gas in the lower layer of the auxiliary tank 73 is transferred to the main heat exchanger 71 through the auxiliary heat exchanger 74 .

Here, the boil-off gas in the upper layer is discharged to the outlet line so as to be mixed and delivered to the liquefied gas transferred to the main heat exchanger 71 through the auxiliary heat exchanger 74 .

The auxiliary heat exchanger 74 transfers the liquefied gas of the auxiliary tank 73 to the main heat exchanger 71 and fills the tank lorry 36 with the liquefied gas of the main heat exchanger 71 .

That is, the auxiliary heat exchanger 74 heat-exchanges the liquefied gas of the auxiliary tank 73 and the liquefied gas of the main heat exchanger 71 to have the same temperature.

At this time, the turbo expander 75 respectively connected between the main heat exchanger 71 and the compressor 72 is further configured.

The turbo expander 75 has a structure in which a pair of impellers synchronously rotating in the center together with the input/output ports divided into both sides are built-in as shown in FIG. 7 .

That is, the high-speed flow of liquefied gas returned from the compressor 72 to the main heat exchanger 71 is passed to generate a rotational force (pressure feeding) at the input/output port of the other side.

The boil-off gas is sucked and compressed from the main heat exchanger 71 through the rotational force generated at the input/output port on the other side.

The compressed boil-off gas is mixed with the liquefied gas transferred to the main heat exchanger 71 through the auxiliary heat exchanger 74 .

When the closed circuit of the tank lorry 36 and the recovery means 70 is continuously passed, all of the boil-off gas of the tank lorry 36 is converted (recovered) into liquefied gas.

Meanwhile, coolers 76 for cooling the liquefied gas are interposed in the piping connected to the compressor 72 , the turbo expander 75 , and the main heat exchanger 71 .

In addition, nitrogen, which is a purge gas that fills the empty space of the converted boil-off gas, may be filled in the tank lorry 36 .

In the above, preferred embodiments of the present invention have been illustrated and described, but the present invention is not limited to the specific embodiments described above, and it is common in the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Of course, various modifications may be made by those having the knowledge of

P: parking area
10: dispenser
20: protective fence
30: trailer
31: chassis frame
32: suspension
33: support legs
34: loading stand
35: support frame
36: tank lorry
36a: outer cylinder
36b: inner tube
36c: roof frame
36d: insulation frame
37: Kingpin
40: pump unit
50: control station
60: pre-cooling means
61: nitrogen tank
62: vacuum pump
63: check valve
70: recovery means
71: main heat exchanger
72: compressor
73: auxiliary tank
74: auxiliary heat exchanger
75: turbo expander
76: cooler

Claims (12)

In a charging station that fills liquefied natural gas (LNG),
One or more dispensers (10) constructed by civil engineering work at a location where at least the LNG filling demand and safety are satisfied, and connected to the vehicle's LNG tank to charge LNG;
a protective fence 20 installed at a location spaced apart from the dispenser 10 by a predetermined distance and providing a parking area P of a set area therein;
a trailer 30 in which a large amount of LNG to be supplied to the dispenser 10 is stored, towed to the parking area P and stored in isolation from the outside;
a pump unit (40) installed in the parking area (P) or the trailer (30) and transferring the LNG stored in the trailer (30) to the dispenser (10);
A control center 50 installed at a position adjacent to the dispenser 10, and a manager who manages the dispenser 10 to the pump unit 40 performs business; including,
The LNG refueling station is
It further includes; recovery means (70) connected to the trailer (30) to convert the boil-off gas generated in the upper layer into liquefied gas and recharge it;
The recovery means 70,
a main heat exchanger 71 connected to the trailer 30 to receive BOG and liquefy the BOG at a low temperature;
a compressor (72) connected to the main heat exchanger (71) to receive boil-off gas, compress the supplied boil-off gas into liquefied gas and return it to the main heat exchanger (71);
an auxiliary tank 73 receiving the main heat exchanger 71 and BOG, and temporarily storing the BOG supplied to be converted into liquefied gas;
It is connected to the trailer 30 and the auxiliary tank 73, respectively, and transfers the stored liquefied gas in the auxiliary tank 73 to the main heat exchanger 71, and transfers the liquefied gas in the main heat exchanger 71 to the trailer 30 ) to the auxiliary heat exchanger (74) supplied to; Consisting of,
The auxiliary tank (73) is a simple LNG refueling station that minimizes boil-off gas, characterized in that the boil-off gas stored therein is mixed with the liquefied gas transferred to the main heat exchanger (71) through the auxiliary heat exchanger (74).
The method according to claim 1,
The trailer 30 is
H-shaped undercarriage frame 31 having a set length and width;
a suspension 32 mounted together with a plurality of wheels at the lower end of the chassis frame 31 and absorbing shocks generated from the ground;
a manual or electric support leg 33 disposed in front of the chassis frame 31 to support it from the ground;
a loading table (34) disposed between the suspension (32) and the supporting legs (33) to accommodate auxiliary wheels or materials;
an arc-shaped support frame 35 mounted on the upper end of the chassis frame 31, the supporting legs 33, and the loading table 34;
a cylindrical tank lorry (36) mounted on the upper end of the support frame (35) and storing a predetermined amount of LNG therein;
a kingpin (37) mounted on the lower end of the front side of the tank lorry (36) and refractably connected to the towing vehicle;
A simple LNG refueling station that minimizes boil-off gas, characterized in that it consists of
3. The method according to claim 2,
The tank lorry 36,
Cylindrical outer cylinder (36a) mounted on the upper end of the support frame (35);
Cylindrical inner cylinder (36b) which is spaced apart mounted at a predetermined distance inside the outer cylinder (36a);
An arc-shaped roof frame (36c) which is mounted so that the upper end of the outer cylinder (36a) is wrapped and spaced apart and blocks heat transfer generated from sunlight to suppress boil-off gas;
An arc-shaped insulating frame (36d) which is spaced apart mounted on the inner surface of the outer cylinder (36b) in close contact with the support frame (35) and blocks heat transferred from the floor to suppress boil-off gas;
A simple LNG refueling station that minimizes boil-off gas, characterized in that it consists of
4. The method of claim 3,
The outer cylinder (36a) is formed of SS275 having a thickness of 9 mm or more, and the inner cylinder (36b) is formed of SUS304 having a thickness of 10 mm or more.
4. The method of claim 3,
The outer cylinder (36a) and the inner cylinder (36b) are mounted at a distance of 240 mm or more from each other, and a vacuum of 1x10 ^-4 Torr or more is formed while the urethane foam is filled between the outer / inner cylinder (36a) and (36b) A simple LNG refueling station that minimizes boil-off gas.
4. The method of claim 3,
The outer cylinder (36a) and the insulating frame (36d) are mounted to be spaced apart from each other at a distance of 175 mm or more, and between the outer cylinder (36b) and the insulating frame (36d) is filled with pearlite powder and a vacuum of 1x10 ^-4 Torr or more is formed A simple LNG refueling station that minimizes boil-off gas, characterized in that.
The method according to claim 1,
The LNG refueling station is
a pre-cooling means (60) for cooling the pipe connected to the dispenser (10) and the pump unit (40) to a low temperature to suppress boil-off gas generated due to a temperature difference when charging the vehicle;
A simple LNG refueling station that minimizes boil-off gas, characterized in that it further comprises.
8. The method of claim 7,
The pre-cooling means (60),
a nitrogen tank 61 connected by a pipe between the dispenser 10 and the pump unit 40 and cooling the pipe to −130° C. or higher by discharging liquid nitrogen before charging LNG into the vehicle;
a vacuum pump 62 connected to the LNG discharge pipe of the dispenser 10 and removing residual liquid nitrogen by sucking the cooled pipe into a vacuum;
a plurality of check valves 63 installed for each pipe connected between the dispenser 10 and the pump unit 40 and the nitrogen tank 61 and the vacuum pump 62 to block the reverse flow of liquid nitrogen;
A simple LNG refueling station that minimizes boil-off gas, characterized in that it consists of
delete delete delete The method according to claim 1,
The recovery means 70,
A turbo expander 75 having a pair of impellers connected between the main heat exchanger 71 and the compressor 72, respectively, and synchronously rotating in the center with input/output ports divided on both sides; is configured,
The turbo expander 75,
A simple LNG refueling station that minimizes boil-off gas, characterized in that the liquefied gas returned from the compressor (72) to the main heat exchanger (71) is passed through to generate a compressive force at the input/output port of the other side.

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