WO2021225400A1

WO2021225400A1 - System for preventing temperature rise in lng iso tank

Info

Publication number: WO2021225400A1
Application number: PCT/KR2021/005725
Authority: WO
Inventors: 강영진
Original assignee: 주식회사 에이원글로벌네트웍스코리아
Priority date: 2020-05-08
Filing date: 2021-05-07
Publication date: 2021-11-11
Also published as: KR20210136553A

Abstract

The present invention relates to a system for preventing temperature rise in temperature in an LNG ISO tank and, more specifically, to a system for preventing the temperature and pressure of extremely low temperature liquefied gas inside an LNG ISO tank from rising due to outdoor air heat during transport of the LNG ISO tank. The system for preventing temperature rise in an LNG ISO tank comprises: a plurality of spray nozzles; a tank frame; a plurality of discharge ports; and a plurality of valves. Also, it is preferable for the plurality of spray nozzles to be installed in the vertical direction from the ground surface toward the upper end so as to be offset from each other. Also, it is preferable for a line connecting the discharge ports to be formed as a self-circulating line. The present invention has the effect in which a temperature rise in an inner tank due to outdoor air heat is suppressed by a self-circulating spray system. Also, the present invention has the effect in which rises in pressure and temperature in the inner tank are suppressed with minimal loss of liquefied natural gas contained therein.

Description

Temperature rise prevention system in LNG ISO tank

The present invention relates to a system for preventing temperature rise in an LNG ISO tank, and more particularly, to a system for preventing an increase in the temperature and pressure of an internal cryogenic liquefied gas due to external heat during transportation of an LNG ISO tank.

Natural gas is widely consumed as an economical and eco-friendly energy. However, the cost and efficiency are lowered due to the volume to be transported in the natural gas state.

In order to supplement this point, a method of transporting in the state of liquefied natural gas (LNG) is widely used.

LNG is stored and transported in ISO tanks, which are container tanks manufactured according to ISO (International Standardization Organization) standards. The internal temperature and pressure continue to increase in proportion to time.

As such, in the conventional LNG ISO tank, the temperature inside the tank rises due to the natural evaporation rate of the internal liquefied natural gas and the external heat over time during transportation. In general, to solve this, the internal pressure of the tank is constant When the pressure increases above the pressure, the safety valve is opened to discharge the boil-off gas inside the tank to the outside.

_{BOG is mainly composed of methane (CH 4} ), which has the lowest boiling point among the components constituting LNG, and since the discharge of BOG to control the tank internal pressure ultimately wastes active ingredients, a significant amount of There is a problem in that LNG is lost.

Therefore, the present invention is to solve this problem, and by applying a self-circulating spray system, the temperature inside the tank is lowered and only a minimum amount of LNG is allowed to be discharged, so that the internal pressure of the LNG ISO tank can be lowered. An object of the present invention is to provide an anti-rise system.

According to one aspect of the present invention for achieving the above object, there is provided a system for preventing temperature rise in an LNG ISO tank including a plurality of spray nozzles, a tank frame, a plurality of outlets, and a plurality of valves.

Preferably, the plurality of spray nozzles may be installed to be staggered toward the top in a vertical direction from the ground surface.

Preferably, the line connecting the outlet may be formed as a self-circulation line.

Preferably, the external exposure member may protrude out of the tank.

In the LNG ISO tank temperature rise prevention system according to the present invention, by applying a self-circulating spray system, it is possible to prevent an increase in the temperature inside the tank due to external heat.

In addition, it is possible to prevent an increase in the temperature and pressure inside the tank while allowing a minimum loss of LNG.

1 is a cross-sectional view schematically illustrating a system for preventing temperature rise in an LNG ISO tank according to an embodiment of the present invention.

2 is a logic diagram schematically illustrating a system for preventing temperature rise in an LNG ISO tank according to an embodiment of the present invention.

3 is a schematic diagram showing a partial front view of a liquefied gas distribution pipe according to an embodiment of the present invention.

4 is a diagram schematically showing a partial top view of a liquefied gas distribution pipe according to an embodiment of the present invention.

In order to fully understand the operational advantages of the present invention and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the configuration and operation of the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, in adding reference signs to the elements of each drawing, it should be noted that only the same elements are indicated by the same reference signs as possible even if they are indicated on different drawings.

Hereinafter, a system for preventing temperature rise in an LNG ISO tank according to an embodiment of the present invention will be described with reference to FIGS. 1 to 2 .

1 and 2 , the LNG ISO tank includes an inner tank frame 20 forming an inner tank in which LNG is directly stored, and an inner tank frame 20 at a predetermined distance from the inner tank frame 20 . It includes an outer tank frame 40 provided in a surrounding form.

The system for preventing temperature rise in an LNG ISO tank according to an embodiment of the present invention includes a liquefied gas distribution pipe 10 provided in an inner tank frame 20 , a plurality of spray nozzles 11 , and a plurality of outlets N1 . , N2, N4, N5).

In addition, the system for preventing temperature rise in the LNG ISO tank of this embodiment further includes a plurality of valves 12 and an external exposure member 30 of the tank.

The liquefied gas distribution pipe 10 of this embodiment is installed in the form of a long rod on the upper part of the inner tank 20 , and a plurality of spray nozzles 11 may be inserted therein.

In addition, as shown in FIGS. 3 and 4 , the plurality of spray nozzles 11 are installed to face the upper end of the distal surface of the inner tank 20, and 45° to each other based on 0° of the distal surface. They can be installed alternately.

The outlet of this embodiment includes a liquefied gas circulation inlet (N2) for discharging the LNG stored in the inner tank and a liquefied gas circulation for re-supplying at least a portion of the LNG discharged through the liquefied gas circulation inlet (N2) to the inner tank. The outlet (N1), the gas outlet (N4) for regulating the pressure for discharging the gas stored in the inner tank to the outside of the inner tank, and for the purpose of discharging gas from the inner tank for the purpose of checking whether the temperature rise prevention system operates normally Includes a cock outlet (N5) for checking icing.

As shown in Figure 2, the liquefied gas circulation inlet (N2) of this embodiment may be provided at the lower end of the inner tank, the liquefied gas circulation outlet (N1), the gas outlet for pressure control (N4) and the coke outlet for checking icing (N5) may be provided at the upper end of the inner tank.

In addition, as shown in Figure 2, the liquefied gas distribution pipe 10 of this embodiment is connected to the liquefied gas circulation outlet (N1).

That is, the liquefied natural gas stored in the internal tank is discharged to the lower part of the internal tank through the liquefied gas circulation inlet (N2), and the liquefied gas circulation inlet (N2) and the liquefied gas circulation outlet (N1) are connected. It is re-supplied to the upper end of the inner tank through the liquefied gas circulation outlet (N1) at the upper end of the inner tank along the connecting circulation line (reference numeral not given). The LNG introduced into the liquefied gas distribution pipe 10 through the liquefied gas circulation outlet N1 is injected and supplied from the upper end of the inner tank through a plurality of spray nozzles 11 provided in the liquefied gas distribution pipe 10 .

The low-temperature liquefied natural gas is vaporized while being sprayed through the plurality of spray nozzles 11, thereby lowering the temperature of the internal tank.

The increase in internal pressure caused by vaporization as the liquefied natural gas is sprayed through the plurality of spray nozzles 11 can be prevented by venting the boil-off gas at the top of the inner tank through the gas outlet for pressure control (N4). have.

According to this embodiment, as a means for confirming whether the temperature rise prevention system according to this embodiment is operating normally, a cock outlet (N5) for checking icing for discharging vaporized liquefied natural gas from the internal tank and It is connected to the cock discharge port (N5) for checking icing and includes a tank external exposure member (30) that is exposed to the outside of the inner tank.

The vaporized liquefied gas is discharged from the inner tank through the cock outlet (N5) for checking icing, and at this time, the vaporized liquefied gas passes through the cock outlet (N5) for checking the icing and is frozen in the exposed member (30) outside the tank Whether the phenomenon occurs can be confirmed by visually observing from the outside of the external tank 40 .

The present invention is not limited to the above embodiments, and it is apparent to those of ordinary skill in the art that various modifications or variations can be implemented without departing from the technical gist of the present invention. did it

10: liquefied gas distribution pipe

11: spray nozzle

12 : valve

20: inner tank frame

30: external exposure member of the tank

40: outer tank frame

N1: liquefied gas circulation inlet

N2: liquefied gas circulation outlet

N4: gas outlet for pressure control

N5 : Cock outlet for checking icing

Claims

an internal tank in which liquefied natural gas is stored;

a liquefied gas circulation inlet provided at the lower end of the inner tank and discharging the liquefied natural gas from the inner tank;

a liquefied gas circulation outlet provided at the upper end of the inner tank and supplying liquefied natural gas to the inner tank;

a plurality of spray nozzles provided at the upper end of the inner tank and spraying and supplying liquefied natural gas; and

a circulation line connecting the liquefied gas circulation inlet and the liquefied gas circulation outlet, and supplying the liquefied natural gas discharged through the liquefied gas circulation inlet to the inner tank through the liquefied gas circulation outlet; and

An LNG ISO tank temperature rise prevention system for lowering the temperature of the inner tank by spraying and vaporizing the liquefied natural gas of the inner tank through the plurality of spray nozzles.
The method according to claim 1,

It is provided at the upper end of the inner tank, and releases the pressure of the gas that rises as the liquefied natural gas sprayed through the plurality of spray nozzles is vaporized, thereby lowering the inner pressure of the inner tank. ISO tank temperature rise prevention system.
The method according to claim 1,

It further comprises a;

When the vaporized liquefied natural gas discharged through the coke outlet for checking icing causes freezing, it can be determined that the gas is operating normally, the LNG ISO tank temperature rise prevention system.
4. The method according to claim 3,

It further includes; a tank external exposure member that is connected to the cock outlet for checking the icing and is exposed to the outside of the inner tank,

A system for preventing temperature rise in an LNG ISO tank that can visually determine whether or not the vaporized liquefied natural gas discharged through the coke outlet for checking icing causes freezing of the exposed member outside the tank.
The method according to claim 1,

It further includes; a liquefied gas distribution pipe connected to the liquefied gas circulation outlet, provided with the plurality of spray nozzles on the surface, and installed in the form of a rod on the upper end of the inner tank,

The plurality of spray nozzles are installed alternately from the ground surface toward the top in the vertical direction, the LNG ISO tank temperature rise prevention system.