KR20100122594A - Apparatus for monitoring an independence type storage tank - Google Patents

Abstract

PURPOSE: An independent storage tank is provided to enable the leakage of liquefied gas to be detected and the leaked amount to be measured since a temperature sensor and a level transmitter are installed on a collecting plate, which is installed on the lower part of the independent storage tank. CONSTITUTION: A monitoring unit of an independent storage tank comprises a collecting plate(10) and a temperature sensor(11). The collecting plate is installed on the lower part of the storage tank and collects the leaked liquefied gas. The temperature sensor is installed on the lower part of the collecting plate and senses the temperature change. A level transmitter(13), which measures the level of the collected liquefied gas, is installed in the collecting plate. An insulating member is attached to the outside of the body(3) of the storage tank, an outlet(5) for discharging the leaked liquefied gas is installed on the lower surface of the insulating member and the collecting plate is installed on the lower part of the discharge.

Description

Tank monitoring device of independent storage tank {APPARATUS FOR MONITORING AN INDEPENDENCE TYPE STORAGE TANK}

The present invention relates to a tank monitoring apparatus of a stand-alone storage tank installed in a liquefied gas carrier that carries LNG, LPG, etc. More specifically, it is possible to detect the leak when liquefied gas leaks from the stand-alone storage tank. In addition, it relates to a tank monitoring device that can help to locate leaks quickly and measure leaks.

Natural gas is transported in a gaseous state through onshore or offshore gas piping, or transported to a distant consumer while being stored in an LNG carrier in the form of liquefied liquefied natural gas (LNG) or liquefied petroleum gas (LPG). Liquefied natural gas is obtained by cooling natural gas to cryogenic temperature (approximately -163 ℃), and its volume is reduced to about 1/600 than natural gas in gas state, so it is very suitable for long distance transportation through sea.

LNG transporter for loading and unloading LNG to land requirements by operating the sea with LNG, or LNG RV (Regasification) that reloads LNG after unloading the sea with LNG for recharging the stored LNG Vessels include storage tanks (commonly referred to as cargo holds) that can withstand the cryogenic temperatures of liquefied natural gas.

Recently, there is a growing demand for floating offshore structures such as LNG Floating, Production, Storage and Offloading (FPSO) or LNG Floating Storage and Regasification Units (FSRUs). Includes a storage tank installed.

LNG FPSO is a floating offshore structure that is used for refining mined natural gas and then liquefying it directly in a storage tank and transferring LNG stored in the storage tank to an LNG carrier if necessary. In addition, the LNG FSRU stores floating LNG unloaded from LNG carriers in storage tanks at seas far from the land, and then vaporizes LNG as needed to supply land demands, thereby eliminating onshore storage and production facilities. It is a structure.

As described above, a storage tank for storing LNG in a cryogenic state is provided in an LNG carrier such as an LNG carrier or an LNG RV for transporting or storing a liquid cargo such as LNG, or an offshore structure such as an LNG FPSO or an LNG FSRU.

These storage tanks can be classified into independent type and membrane type depending on whether the load directly affects the insulation material.Membrane type storage tanks are usually GT NO 96 type and TGZ Mark III type. Independent storage tanks are divided into MOSS type and SPB type. The structure of the MOSS type independent storage tank is described in Korean Patent No. 10-15063 and the like, and the structure of the SPB type independent storage tank is described in Korean Patent No. 10-305513 and the like.

Generally, a standalone storage tank according to the prior art is made by attaching a relatively rigid insulation panel such as polyurethane to a tank body made of aluminum alloy and is placed on a plurality of tank supports arranged on the inner bottom of the hull.

Further, below the independent storage tank according to the prior art, an outlet for discharging the liquid leaked when the liquefied gas leaks, and a collecting plate for collecting the liquid falling from the outlet is provided.

The structures of these outlets and the collecting plate in the independent storage tank according to the prior art are described in Japanese Patent Laid-Open No. Hei 7-52870, Korean Patent No. 10-189306, and the like.

Figure 1 shows a schematic installation position of the outlet and the collecting plate of the stand-alone storage tank according to the prior art, Figure 2 shows one embodiment of the outlet and the collecting plate of the stand-alone storage tank according to the prior art.

As illustrated in FIGS. 1 and 2, a standalone storage tank according to the prior art is made by attaching a relatively hard insulating material 4 such as polyurethane foam to the outside of the tank body 3.

At the bottom of the tank body 3, discharge ports 5 for discharging the liquid leaked from at least four corners are provided, and these discharge ports 5 are mounted on the lower surface of the heat insulating material 4.

Below the outlet 5, a collecting plate 6 for collecting the liquid discharged through the outlet 5, ie liquefied gas, is located, and between the collecting plate 6 and the hull inner surface 1 is insulated. (7) is interposed so that the collection plate 6 may be spaced apart from the inner surface 1 of the hull by a predetermined distance.

As described above, according to the related art, even in an emergency in which liquefied gas leaks from the storage tank, the leaked liquefied gas is prevented from falling directly on the inner surface 1 of the ship body, thereby securing the safety of the ship.

However, the outlet 5 and the collecting plate 6 of the independent storage tank according to the prior art merely prevent the leaked liquefied gas from contacting the hull inner surface 1 and can detect whether the liquefied gas is leaked. Since the gas detector detects the evaporation gas generated while the liquefied gas dropped on the collecting plate 6 has evaporated, it is judged whether or not the liquefied gas leaks.

Further, according to the outlet 5 and the collection plate 6 of the independent storage tank according to the prior art, not only can not detect whether the liquefied gas leaks, but also the amount of leak and the leak position can not be confirmed at all. Therefore, there is a problem that quick and accurate situation determination and countermeasures cannot be made in an emergency where leakage of liquefied gas actually occurs due to breakage of the storage tank.

The present invention for solving these problems, by installing a temperature sensor and a level transmitter on the collecting plate installed below the stand-alone storage tank to collect the leaked liquefied gas, when the liquefied gas leaks from the storage tank The aim is to provide a tank monitoring device that not only detects leaks but also helps to quickly locate leaks and measure leaks.

According to an aspect of the present invention for achieving the above object, as a tank monitoring device of the stand-alone storage tank for monitoring whether the liquefied gas leaked in the stand-alone storage tank, so as to collect the liquefied gas leaked when the liquefied gas leak A collecting plate installed below the storage tank; A temperature sensor installed at a lower portion of the collecting plate to detect a change in temperature; Tank monitoring device comprising a.

The tank monitoring device preferably includes a level transmitter for measuring the level of the liquefied gas collected in the collection plate.

The storage tank is made of a heat insulating material attached to the outside of the tank body, the lower surface of the heat insulating material from the bottom of the tank body is provided with a discharge port for discharging the leaked liquefied gas, the collection plate is located below the discharge port It is preferable to install.

The temperature sensor is preferably installed directly below the outlet.

The collection plate preferably has an extension portion that is bent and extended toward the inside of the collection plate at an upper end, so that the liquefied gas collected in the collection plate can be prevented from overflowing even when the hull swings.

It is preferable that the said collection plate is installed in several places under the tank body, and the said temperature sensor is installed in each of the said several collection plate.

Preferably, the tank monitoring device further includes a control unit for determining whether the liquefied gas leaks or not, based on temperature information transmitted from each of the temperature sensors.

The plurality of collection plates are each provided with a level transmitter for measuring the level of the collected liquefied gas, the control unit preferably determines the degree of damage of the storage tank based on the water level information transmitted from each of the level transmitter. Do.

In addition, according to another aspect of the present invention, as a tank monitoring device of the independent storage tank for monitoring whether the liquefied gas leaked in the independent storage tank, the storage tank to collect the liquefied gas leaked when the liquefied gas leakage A collecting plate installed at the bottom of the; A level transmitter for measuring the level of liquefied gas collected in the collection plate; Tank monitoring device comprising a.

In addition, according to another aspect of the present invention, as a tank monitoring method of the standalone storage tank for monitoring whether the liquefied gas contained in the standalone storage tank leaks, by detecting the temperature change by the leaked liquefied gas by the temperature sensor liquefied gas Tank monitoring method is provided, characterized in that for determining whether the leak.

Preferably, the tank monitoring method further includes a step of determining a leak position through temperature change information according to time detected by the temperature sensor installed at a plurality of locations below the storage tank.

The tank monitoring method preferably further comprises the step of measuring the level of the leaked liquefied gas by the level measuring means to determine whether the liquefied gas leaks and at the same time determine the degree of breakage of the storage tank.

According to the present invention as described above, by installing a temperature sensor and a level transmitter on the collecting plate installed below the stand-alone storage tank to collect the leaked liquefied gas, whether or not leaked when the liquefied gas leaks from the storage tank In addition to being able to detect, tank monitoring can be provided to aid in the quick identification of leaks and to measure leaks.

According to the tank monitoring device of the independent storage tank of the present invention, since the leakage amount of the liquefied gas can be measured, the degree of breakage of the storage tank can be predicted, and planning of maintenance work becomes easy.

In addition, according to the tank monitoring device of the independent storage tank of the present invention, since the temperature change information sensed by the temperature sensor installed in each collection plate can be synthesized to roughly grasp the leak location, the leak location is confirmed and repaired. This saves time and effort.

Hereinafter, a tank monitoring apparatus of a standalone storage tank according to a preferred embodiment of the present invention will be described in detail with reference to the drawings.

3 shows a tank monitoring device of a standalone storage tank according to a preferred embodiment of the present invention. As shown in FIG. 3, the tank monitoring apparatus of a standalone storage tank according to a preferred embodiment of the present invention includes a collecting plate 10 installed below the standalone storage tank and collecting the leaked liquefied gas, and the collecting plate. And a temperature sensor 11 installed below the 10.

In the independent storage tank, a relatively hard heat insulating material 4 is attached to the outside of the tank body 3 as in the prior art, such as polyurethane foam. On the lower surface of the heat insulating material 4 below the tank body 3, discharge ports 5 for discharging the leaked liquid are provided, and these discharge ports 5 are mounted on the lower surface of the heat insulating material 4. .

The installation position of the outlet 5 can be formed at each of these four corners when the tank body 3 has a quadrilateral bottom, and a pump well at the bottom of the tank body 3, although not shown. When the concave portion is formed as described above, the outlet 5 may be installed below it.

In addition, the installation position and the number of installation of the discharge port 5 can be changed according to the size or shape of the tank body (3), of course.

Below the outlet 5, a collecting plate 10 for collecting liquid, ie liquefied gas, which has leaked from the tank body 3 and is discharged through the outlet 5 is located, and this collecting plate 10 and An insulating material 7 is interposed between the inner surface 1 of the hull so that the collecting plate 10 can be spaced apart from the inner surface 1 of the hull by a predetermined distance.

As described above, according to the present invention, even in an emergency in which liquefied gas leaks from the storage tank, the leaked liquefied gas is prevented from falling directly on the inner surface 1 of the hull to secure the safety of the hull. That is, the tank body 3 may serve as a primary barrier for preventing leakage of liquefied gas, and the collecting plate 10 may serve as a secondary barrier.

Furthermore, according to the tank monitoring device according to the present invention, since the temperature sensor 11 is provided in the lower portion of the collecting plate 10, the liquefied gas in a low temperature state falls from the discharge port 5 to the collecting plate 10. It is possible to detect whether the liquefied gas leaks through the temperature change of the collecting plate 10 when it is dropped.

According to the present invention, the temperature sensor 11 detects a change in temperature and transmits this temperature information to a controller (not shown), and the controller controls the liquefied gas based on the temperature information transmitted from each temperature sensor 11. Determine if there is a leak. In addition, the control unit can determine the approximate position of leakage of the liquefied gas based on the difference between the times at which the temperature change of each temperature sensor 11 occurs.

Here, the temperature sensor 11 is installed directly below the outlet 5, that is, directly below the outlet 5 as shown by the dashed-dotted line in FIG. 3 so that leakage of the liquefied gas can be detected quickly. It is preferable.

On the other hand, the tank monitoring device according to the present invention measures the level of the liquefied gas collected inside the collecting plate 10 and transmits a level transmitter 13 as a level measuring means for transmitting the level information to the control unit. It may include. The level transmitter may be used to measure the water level using a laser, and any configuration may be used as long as the level of the liquefied gas in the cryogenic state may be measured.

The controller may determine whether the liquefied gas leaks based on the water level information transmitted from each level transmitter 13. In addition, the control unit may determine the approximate leakage position of the liquefied gas or the degree of damage based on the change in the water level with time of each level transmitter 13.

The level transmitter 13 may be installed in place of the above-described temperature sensor 11 so as to determine whether the liquefied gas leaks and the leaked position, and cooperate with the temperature sensor 11 to obtain more accurate information. It may be installed.

In addition, the collecting plate 10 of the present invention has an extension portion 10a that is bent and extended toward the inner side of the collecting plate at an upper end thereof to prevent the liquefied gas collected in the collecting plate 10 from overflowing even when the hull swings. Can be.

The tank monitoring apparatus of the present invention as described above may be applied to any floating marine structure provided with an independent storage tank. That is, the tank monitoring apparatus of the present invention can store a liquefied gas carrier that carries liquefied natural gas (LNG) or liquefied petroleum gas (LPG), a vessel such as LNG RV, or LNG or LPG while floating at sea. It can be applied to both floating offshore structures such as offshore plants such as LNG FPSO and LNG FSRU.

As described above, the tank monitoring apparatus of the independent storage tank according to the present invention has been described with reference to the illustrated drawings, but the present invention is not limited by the embodiments and drawings described above, and the present invention within the claims. Of course, various modifications and variations can be made by those skilled in the art.

1 is a plan view of the main part of a stand-alone storage tank according to the prior art,

Figure 2 is a side cross-sectional view of the oil portion of the independent storage tank according to the prior art, and

Figure 3 is a side cross-sectional view of the tank monitoring device of the independent storage tank according to the present invention.

Description of the Related Art

1 hull inner surface 3 tank body

4, 7: insulation material 5: outlet

10: collecting plate 10a: extension

11: temperature sensor 13: level transmitter

Claims (12)

A tank monitoring device of a standalone storage tank that monitors leakage of liquefied gas contained in a standalone storage tank. A collecting plate installed below the storage tank to collect the leaked liquefied gas when the liquefied gas leaks; A temperature sensor installed at a lower portion of the collecting plate to detect a change in temperature; Tank monitoring device comprising a. The method according to claim 1, Tank monitoring device comprising a level transmitter for measuring the level of the liquefied gas collected in the collection plate. The method according to claim 1, The storage tank is made of a heat insulating material attached to the outside of the tank body, the lower surface of the heat insulating material from the bottom of the tank body is provided with a discharge port for discharging the leaked liquefied gas, the collection plate is located below the discharge port Tank monitoring device, characterized in that installed. The method according to claim 3, The temperature sensor is a tank monitoring device, characterized in that installed below the outlet. The method according to claim 1, The collection plate, the tank monitoring device, characterized in that the upper end has an extension that extends bent toward the inside of the collection plate, the liquefied gas collected in the collection plate can be prevented from overflowing even if the hull swings. The method according to claim 1, The collection plate is installed in a plurality of places at the bottom of the tank body, the temperature sensor is a tank monitoring device, characterized in that installed in each of the plurality of collection plates. The method according to claim 6, And a control unit for determining whether or not the liquefied gas leaks at the same time based on temperature information transmitted from each of the temperature sensors. The method of claim 7, The plurality of collection plates are each provided with a level transmitter for measuring the level of the collected liquefied gas, the control unit for determining the damage level of the storage tank based on the water level information transmitted from each of the level transmitter Tank monitoring device, characterized in that. A tank monitoring apparatus of a stand-alone storage tank for monitoring the leakage of liquefied gas contained in the stand-alone storage tank, comprising: a collecting plate installed below the storage tank to collect the liquefied gas leaked when the liquefied gas leaks; A level transmitter for measuring the level of liquefied gas collected in the collection plate; Tank monitoring device comprising a. Tank monitoring method of a stand-alone storage tank that monitors the leakage of liquefied gas contained in the stand-alone storage tank, Tank monitoring method, characterized in that by detecting the temperature change by the leaked liquefied gas by the temperature sensor to determine whether the liquefied gas leak. The method according to claim 10, The tank monitoring method further comprising the step of determining the leak position through the temperature change information according to the time detected by the temperature sensor installed in a plurality of places at the bottom of the storage tank. The method according to claim 10, And measuring the level of the leaked liquefied gas by a level measuring unit to determine whether the liquefied gas is leaked and to determine the degree of breakage of the storage tank.

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