KR102027305B1 - Cooling system with energy saving for refeer container - Google Patents

Abstract

The present invention relates to an energy-saving cooling system for a refrigerated container, and more specifically, to an energy-saving cooling system for a refrigerated container which reduces power consumption by cooling a refrigerated container by using vaporization heat of liquefied LNG in a container ship using the liquefied LNG as fuel. The cooling system used in the container ship having a cargo hold capable of loading the refrigerated container comprises: an LNG tank in which the liquefied LNG is stored; a high-pressure pump moving the liquefied LNG from the LNG tank; an evaporator evaporating the liquefied LNG moved by the high-pressure pump; a glycol line installed to allow heat exchange with the evaporator; and a cargo hold fan installed in the cargo hold to allow the air inside the cargo hold to undergo convection movement.

Description

Energy-saving refrigerated container cooling system {Cooling system with energy saving for refeer container}

The present invention relates to an energy-saving refrigerated container cooling system, and more particularly, by cooling the refrigerated container by using the vaporization heat of the liquefied LNG in a container ship that uses liquefied LNG as fuel, the energy-saving refrigeration is reduced power consumption. A container cooling system.

In general, containers are used for long distance logistics such as exports and imports arising from trade between countries. In order to reduce the logistics cost and mass transportation, most ships are used. Due to problems such as exhaust gas, conventionally used diesel engines have been designed to use other engines.

In Liquified Natural Gas Carrier, a method of supplementing liquefied LNG, BOG (Boil Off Gas), which is naturally vaporized, is used as a supplementary fuel.However, due to the above-mentioned problem, an engine using LNG as a main fuel is used. Container ships have been developed for loading, storing and operating liquefied LNG.

The container ship is moved by lashing the container in the cargo hold. As described above, the container can be transported by storing various kinds of cargo that can be exported and imported.

Among the items that need to be refrigerated or frozen, a separate refrigeration container is provided, which is equipped with a separate refrigeration and freezing device, which enables refrigeration such as individual refrigeration and freezing. Since it is necessary to maintain a constant temperature continuously, the power required for this can be a factor that increases the operating cost in the ship that supplies power through its own generator.

In order to maintain the cooling performance of the refrigerated container using the minimum power, as a method of using the cooling heat due to the vaporization of the liquefied LNG used as the engine of the ship, a method to circulate the cooling heat directly to the refrigerated container is devised However, this has a problem that the cooling is not maintained when the ship is stopped or the container is unloaded, even if the ship is in operation. In addition, the existing design has a problem that it is difficult to apply a general purpose, such as a separate configuration that must be supplied directly to the refrigeration container, that is, the refrigerated container must be individually modified or reproduced.

KR 10-2017-0078507 A KR 10-1567856 B1

The present invention has been invented to solve the above problems, by supplying the air cooled by the cooling heat in the cargo hold where the refrigerated container is stored, thereby increasing the cooling efficiency of the refrigerated container to be cooled by using the cooled air The purpose is to provide an energy-saving refrigerated container cooling system with reduced power consumption.

The object of the present invention is not limited to the above-mentioned object, and other objects which are not mentioned will be clearly understood from the following description.

Energy-saving refrigerated container cooling system according to the present invention for achieving the above object is a cooling system used in a container ship equipped with a cargo hold for loading the refrigerated container, the engine using a liquefied LNG, the liquefaction LNG tank where LNG is stored; A high pressure pump for moving the liquefied LNG from the LNG tank; A vaporizer for vaporizing the liquefied LNG moved by the high pressure pump; A glycol line installed to allow heat exchange with the vaporizer; And a cargo hold fan installed at the cargo hold to allow air inside the cargo hold to be convection.

The present invention by the above configuration can be expected the following effects.

As the cooling performance of the refrigerated container is improved, the power consumed to maintain the cooling temperature inside the refrigerated container can be reduced. In consideration of the fact that this is a ship that produces power used in an isolated environment by a generator provided therein, a reduction in power consumption may result in lowering a required operation rate of the generator, thereby obtaining a substantial effect.

In particular, the above-described savings will ultimately lead to a reduction in logistics costs, so that the operator can maximize the profits from trade.

In container ships using liquefied LNG as the main raw material for engine driving, the cooling performance is raised by using the heat of cooling generated during the vaporization process of liquefied LNG, which is essential for driving by using liquefied LNG. In particular, it is possible to obtain an effect, and in particular, it is applied to an LNG engine with less leakage of exhaust gas, and thus can be adopted by many carriers, thereby preventing environmental pollution.

In order to supply cooling heat to each of the conventionally designed refrigerating containers, a separate facility for circulating the cooled air in each refrigerating container should be provided, or each refrigerating container should be remodeled. This is economically efficient and simple to apply.

In particular, in consideration of the diversity of the environment in which a ship operates, the heat of cooling due to vaporization of liquefied LNG is used when passing through a cold region requiring cooling, and a general fan is used when passing through a cold region where cooling is unnecessary. It can be operated in a dual way to restrain unnecessary cooling system operation, resulting in greater power consumption savings.

1 is an overall configuration diagram of an energy-saving refrigerated container cooling system according to an embodiment of the present invention.
Figure 2 is a flow chart of the cooler operation of the glycol line according to an embodiment of the present invention.

Hereinafter, described in detail with reference to the accompanying drawings an energy-saving refrigerated container cooling system according to a preferred embodiment of the present invention.

1 is an overall configuration of the energy-saving refrigerated container cooling system according to an embodiment of the present invention and Figure 2 is a flow chart of the cooler operation of the glycol line according to an embodiment of the present invention.

Energy-saving refrigerated container cooling system according to a preferred embodiment of the present invention is LNG tank 100, high pressure pump 200, vaporizer 300, glycol line 400 and cargo hold pan 500 as shown in FIG. It is composed of

First, look at the vessel that can be provided with the present invention.

The present invention relates to an apparatus for reducing the power consumption of the cooling device of the refrigerated container by cooling the cargo hold 10 of the container ship by using the cooling heat generated in the process of vaporizing to use the liquefied LNG as an engine.

Therefore, the vessel to which the present invention can be applied should be able to operate the engine for the operation of the vessel using the liquefied LNG. In addition, the present invention is intended to improve the cooling efficiency of the refrigerated container mounted on the container ship as described above, should correspond to the container ship.

However, liquefied LNG and an engine used in parallel with a general diesel engine may also be provided, so the engine is not necessarily operated by liquefied LNG. In addition, in the case of ship type, since the ship is able to form various ship types according to the demand of the ship owner, it may be dried so that other cargoes can be loaded in addition to the container, and in extreme cases carrying the container and the liquefied LNG together. It is not necessarily confined to container ships either.

However, since the present invention improves the cooling efficiency of the refrigerated container by supplying the cooling heat according to the vaporization of the liquefied LNG to the cargo hold 10 equipped with the refrigerated container, the cargo hold 10 and the individual cooling function loaded thereon Refrigerating containers with must be provided.

First, look at the LNG tank (100).

The LNG tank 100 is a space in which the liquefied LNG is stored, and may be thermally insulated to maintain cryogenic temperature of −163 ° C. or less, which is the vaporization point of LNG at atmospheric pressure.

In addition, since leakage of liquid liquefied LNG and a pressure excess may cause a large accident such as an explosion, the shape may have a specific type of membrane type or Moss type in consideration of structural stability. Various forms may be possible depending on spatial constraints or requirements such as utilization and stability.

Next, look at the high-pressure pump 200.

The high pressure pump 200 to move the liquefied LNG to the vaporizer 300 to be described later. In general, the high-pressure pump 200 may generate a high pressure for the transport of the material to make the liquefied LNG from the LNG tank 100 by making a pressure difference.

The liquefied LNG stored in the LNG tank 100 is to be supplied for driving the ship engine, it is to move the LNG in the liquid state by the action of the high-pressure pump (200).

In the embodiment of Figure 1, the upper and lower path formed in the upper path of the liquefied LNG supply line (A), the movement of the liquefied LNG by the high pressure pump 200 is made in the liquid state, which will be described later The vaporization of the liquefied LNG is carried out by the vaporizer 300 to utilize the cooling heat generated. On the other hand, the path formed at the lower part is a BOG supply line (B), and since BOG naturally occurring in the LNG tank 100 is in a gaseous state, cooling heat due to vaporization cannot be obtained, and the high pressure pump 200 can move it. Since it is not necessary, the high pressure pump 200 may be provided only in the upper path.

Next, look at the vaporizer 300.

The vaporizer 300 is installed between the high-pressure pump 200 and the engine, by applying heat to the liquefied LNG moved by the high-pressure pump 200 to cause a phase change to the liquid LNG to make a gaseous state Can be.

When LNG is a gaseous gas, it can be used as a fuel of an engine. For convenience of storage and large-sized transportation, the LNG is transported in a liquid state in which the volume is reduced to 1/250 compared to the gaseous state.

Therefore, the vaporizer 300 should be installed so as to cause phase change again in order to use the liquid LNG as the main fuel. In the case of the BOG, as described above, the vaporizer 300 is unnecessary.

In order to cause the phase change of the LNG from the liquid to the gas, heat must be applied to the liquid LNG at normal pressure, so that the heat exchange is performed in the vaporizer 300.

Due to this heat exchange, the material which transfers heat to the liquid LNG is cooled by the counterpart, and this property can be used to achieve the object of the present invention.

Next, look at the glycol line (400).

As described above, heat exchange in the vaporizer 300 is performed by the glycol line 400.

In the past, seawater or propane gas was used as a heating medium for vaporization of liquid LNG. However, due to the deterioration of durability due to the use of seawater and safety problems due to the use of propane gas, Glycol, which is used as an antifreeze while having the property of alcohol, may be used.

The glycol line 400 may include a glycol tank 410, a glycol heater 430, and a cooler 450.

The glycol tank 410 is a place to store the glycol, it is connected to the vaporizer 300 may supply the glycol so that the heat exchange with the liquid LNG.

After the heat exchange is performed with the liquid LNG, the cooled glycol may be heated by the glycol heater 430 to be at a constant temperature since the heat exchange with the liquid LNG should be performed again through circulation. Even if the cooling heat of the glycol cooled by the cooler 450 to be described later is supplied to the cargo hold 10, since the glycol does not recover back to the temperature before heat exchange, the glycol heater 430 should be heated up to a predetermined temperature. Can be.

The glycol heater 430 may be formed at one side of the glycol tank 410 to heat the glycol before the glycol is supplied for heat exchange with the vaporizer 300.

The glycol supplied to the vaporizer 300 from the glycol tank 410 is heat-exchanged with the liquid LNG in the vaporizer 300, the heat of the glycol is transferred to the liquid LNG, the glycol is cooled.

Due to the cooling heat, the cooled glycol may act as a refrigerant, and the air cooled by the refrigerant may be supplied to the cargo hold 10 by the cooler 450 provided with the cooling fan 451.

Looking at the operation of the glycol line 400, the glycol supplied from the glycol tank 410 is supplied for heat exchange with the vaporizer (300).

Through heat exchange, the liquid LNG is vaporized and fed to the engine, and the glycol is cooled and moved.

The cooler 450 cools the air by using the cooled glycol as a refrigerant, and the air cooled by the cooling fan 451 included in the cooler 450 is supplied to the cargo hold 10.

The cooled glycol is heated again after being used as a refrigerant, but needs to be reheated for heat exchange in the vaporizer 300 again by circulation, and may be reheated by the glycol heater 430.

The reheated glycol may be stored in the glycol tank 410 and may repeat the above process.

Looking at the whole process of the glycol line 400, glycol is made of two heat exchange in the vaporizer 300 and the cooler 450.

Finally, the cargo hold fan 500 will be described.

The cargo hold fan 500 may be installed at one side of the cargo hold 10 to allow the air inside the cargo hold 10 to be convection. Cargo hold 10 may be formed as a closed space, it is generally an element that can be provided so a detailed description will be omitted.

Based on the above-described components, look at the selective operation process of the present invention.

By the glycol line 400 which is the above-described component, the cooled air is supplied to the cargo hold 10, and the air cooled by the cargo hold fan 500 is convexed in the cargo hold 10, whereby cargo The temperature inside the hold 10 can be kept low.

As described above, the refrigerating container can be individually cooled, but since the individual cooling of the refrigerating container is made by condensation of air in the cargo hold 10, the temperature of the inside of the cargo hold 10 is kept low, thereby freezing the container. The individual cooling efficiency of is increased. As a result, the increase in the individual cooling efficiency of each refrigerated container to reduce the power consumption required, it is possible to save energy, which is the object of the present invention.

In addition, the cooler 450 of the glycol line 400 may be controlled according to the environment in which the ship operates.
When the outside temperature is higher than the cargo hold set temperature, the cooler 450 is operated. When the outside temperature is lower than the cargo hold set temperature, the cooler 450 is stopped in accordance with the outside air temperature by stopping the cooler 450. Can be selectively operated.

That is, when the temperature at which the vessel is operated is a harsh environment, the air inside the cargo hold 10 may be kept low, and thus the cooler 450 of the glycol line 400 may not be operated. On the contrary, when the temperature at which the vessel is operated is in a harsh or warm environment, the air temperature inside the cargo hold 10 may be lower than the cooling temperature, so that the cargo hold is operated by operating the cooler 450 of the glycol line 400. (10) The temperature inside can be lowered.

The cargo hold fan 500 is constantly operated, and a circulation system may be provided to circulate air in the cargo hold 10.

The above embodiments are merely exemplary, and those having ordinary skill in the art may have other embodiments modified in various ways.

Therefore, the true technical protection scope of the present invention should include not only the above embodiment but also various other embodiments modified by the technical spirit of the invention described in the claims below.

100: LNG tank
200: high pressure pump
300: carburetor
400: glycol line
410: glycol tank
430 glycol glycol
450: cooler
451: cooling fan
500: cargo hold pan
10: Cargohold
A: Liquefied LNG Supply Line
B: BOG Supply Line

Claims (4)

In a cooling system used for a container ship equipped with a cargo hold for loading a refrigerated container is used an engine using a liquefied LNG,
An LNG tank in which the liquefied LNG is stored;
A BOG supply line which is a path through which the BOG generated in the LNG tank moves;
A liquefied LNG supply line which is a path through which the liquefied LNG moves;
A high pressure pump for moving the liquefied LNG from the LNG tank through the liquefied LNG supply line;
A vaporizer for vaporizing the liquefied LNG moved by the high pressure pump;
A glycol line installed to allow heat exchange with the vaporizer; And
Is installed in the cargo hold but is configured to include a cargo hold fan to allow the air inside the cargo hold,

The glycol line is,
Glycol tanks in which glycols are stored;
A glycol heater installed at one side of the glycol tank to increase a temperature of the glycol flowing into the glycol tank; And
And a cooler configured to supply cold air to the cargo hold using the glycol cooled by heat exchange with the vaporizer as a refrigerant.

And operate the cooler when the outside air temperature is higher than the cargo hold set temperature, and stop the cooler when the outside air temperature is lower than the cargo hold set temperature. delete delete The method of claim 1,
Energy-saving refrigerated container cooling system further comprises an air circulation system for circulating the air in the cargo hold.

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