KR102426720B1 - Cryogenic liquid pump using pneumatic motor and transfer method of cryogenic liquid using the same - Google Patents

Abstract

Disclosed are a cryogenic liquid transport system using a pneumatic motor and a cryogenic liquid transport method using the same. According to an aspect of the present invention, a pumping unit for transferring the cryogenic liquid provided from the storage tank to the outside; and a driving unit providing compressed gas for driving to the pumping unit, wherein the compressed gas is partially or entirely provided from the cryogenic liquid, and the driving unit is a pneumatic motor driven by rotation by the pressure of the compressed gas Containing, a cryogenic liquid transport system may be provided. The transport system and transport method of the present invention can reduce transport loss of cryogenic liquid due to heat.

Description

Cryogenic liquid pump using pneumatic motor and cryogenic liquid transfer method using the same

The present invention relates to a cryogenic liquid pump for transporting a cryogenic liquid such as liquefied natural gas, and a cryogenic liquid transport method using the same.

In general, a pump is a device that generates a differential pressure by rotating an impeller, a gear, and the like, and moves a fluid using the generated differential pressure. An electric motor driven pump is used to transport cryogenic liquids such as liquefied natural gas (LNG). Specifically, in the case of liquefied natural gas at -162 degrees, a pump is installed in the lower part of the tank by a submerged motor pump method, and an impeller is rotated using the rotational force of an electric motor as a driving force to transfer the liquefied natural gas. are using

A pump for cryogenic liquids such as liquefied natural gas may include a pump body in a pump housing, and a submersible pump type pump having an impeller therein. Here, an electric motor is usually used to rotate the impeller, and the use of such an electric motor may generate additional boil off gas (BOG). That is, the driving heat generated by the electric motor promotes the vaporization of the liquefied natural gas in a cryogenic state. In addition, in order to supply electricity to the electric motor, it must be provided for installing a wire cable in the pump housing in which cryogenic liquid (liquefied natural gas) is stored, and furthermore, the pump housing can be dismantled for replacement or repair of the electric motor. Since it has to be manufactured, there is a disadvantage in that it cannot but be composed of a structure that is vulnerable to heat insulation.

Registered Patent No. 10-1710997 (Registered on February 22, 2017)

An object of the present invention is to provide a cryogenic liquid pump capable of reducing the generation of vaporized gas during transport of a cryogenic liquid such as liquefied natural gas, and a transport method using the same.

According to an aspect of the present invention, a pumping unit for transferring the cryogenic liquid provided from the storage tank to the outside; and a driving unit providing compressed gas for driving to the pumping unit, wherein the compressed gas is partially or entirely provided from the cryogenic liquid, and the driving unit is a pneumatic motor driven by rotation by the pressure of the compressed gas A cryogenic liquid transport system comprising a can be provided

According to another aspect of the present invention, there is provided a method for transferring a cryogenic liquid using the transfer system, wherein a compressed gas generated from a cryogenic liquid, which is a transfer object, is used as a driving source of a pneumatic motor. can

According to the present invention, by applying a method of rotating a pneumatic motor by compressing a part of its own gas as a driving method of a pump for transporting cryogenic LNG, the cryogenic LNG is vaporized and vaporized due to the heat generated from the electric motor when using the electric motor method. Gas (BOG) generation can be suppressed, and electricity is not supplied within the pump body, so it is possible to reduce the difficulty of preparing a port for electricity supply and the risk of electric sparks, etc. It has the advantage of being able to easily cope with a pump failure. This method can be applied not only to cryogenic LNG pumps, but to facilities for pumping various dangerous substances such as LPG.

1 is a schematic diagram illustrating a cryogenic liquid transport system according to an embodiment of the present invention.
FIG. 2 is a modified example of the transport system shown in FIG. 1 .
3 is a schematic diagram showing an example of the pneumatic motor shown in FIG.
FIG. 4 is an operation state diagram of the transport system shown in FIG. 1 .

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be noted that the following examples are provided to help the understanding of the present invention, and the scope of the present invention is not limited to the following examples. The following embodiments are provided to more completely explain the present invention to those with average knowledge in the relevant technical field, and detailed description of known configurations that may unnecessarily obscure the technical gist of the present invention to be omitted.

1 is a schematic diagram illustrating a cryogenic liquid transport system according to an embodiment of the present invention.

Referring to FIG. 1 , the cryogenic liquid transport system (hereinafter, referred to as “cryogenic liquid pump 100”) according to the present embodiment transfers the cryogenic liquid stored in the storage tank 10 to the cryogenic storage tank of a vehicle or ship. It can be used to supply or transport cryogenic liquids to some other storage means.

Here, the cryogenic liquid may typically include liquefied natural gas (LNG). However, the cryogenic liquid may include various types of liquid substances other than liquefied natural gas. For example, the cryogenic liquid may include liquefied petroleum gas (LPG), other liquefied gas cooled to below a critical temperature and treated as a liquid state (liquefied gas). In addition to this, the cryogenic liquid may include liquid nitrogen, liquid oxygen, liquid helium, liquid carbonic acid, and the like.

Hereinafter, for convenience of explanation, a case in which the liquefied natural gas is a cryogenic liquid will be exemplified. However, the technical gist to be described below may be equally or similarly applied to liquefied petroleum gas and other liquefied gases.

The storage tank 10 may have a predetermined heat insulation structure and may store liquefied natural gas, and the type, use, structure, and the like are not particularly limited. For example, the storage tank 10 may be a storage means provided in a liquefied natural gas filling station, an LNG bunkering facility, a liquid transport facility such as liquefied petroleum gas, and the like. Smaller, a tank provided in a transport vehicle of liquefied natural gas may also be included as a kind of the storage tank 10 . In addition, the storage tank 10 may include a tank for storing a liquid requiring a predetermined pressure, such as liquefied petroleum gas.

Meanwhile, the cryogenic liquid pump 100 of the present embodiment may include a pumping unit 110 and a driving unit 120 .

The pumping unit 110 may supply the liquefied natural gas provided from the storage tank 10 to a predetermined other storage means or a storage means of a demand. In some cases, the liquefied natural gas may be temporarily stored in the pumping unit 110 and then transferred to another predetermined storage means.

The driving unit 120 may provide a driving force for transport to the pumping unit 110 . In the present embodiment, the pumping unit 110 may be driven by pneumatic, and accordingly, the driving unit 120 may provide a predetermined pneumatic pressure to the pumping unit 110 .

Here, the driving unit 120 of the present embodiment may use some vaporized gas obtained from the cryogenic liquid as a driving source. As illustrated, when the cryogenic liquid is liquefied natural gas, the vaporized gas may be gaseous natural gas (NG) obtained from liquefied natural gas.

The method of using gaseous natural gas as a driving source makes it possible to easily obtain a driving source in the cryogenic liquid pump 100 and, in some cases, to easily supplement the driving source.

Another advantage is that it is possible to prevent vaporization of the cryogenic liquid due to heat generation from the pumping unit 110 compared to the conventional method using a motor using electricity. Conventionally, a driving source such as an electric motor, which has been generally used, has used a cool-down method through heat exchange with a cryogenic liquid in order to remove heat generated during operation. Although the temperature of the temperature rises and is partially vaporized, it has to be supplied in a liquid state, there has been a disadvantage that it is not possible. Since the cryogenic liquid pump 100 of this embodiment uses a method of rotating the impeller using pneumatic pressure without using electricity in the pumping unit 110, there is no risk of heat generation, so the problem due to vaporization in transporting the cryogenic liquid is eliminated. can be prevented. This will be described in detail in relation to the pumping unit 110 to be described later.

Hereinafter, the pumping unit 110 will be described in more detail.

The pumping unit 110 may include a pump housing 111 . The pump housing 111 may form a chamber 111a therein. The chamber 111a serves to temporarily store the liquefied natural gas transferred from the storage tank 10 so that the impeller is always located in the liquid. As long as the pump housing 111 or the chamber 111a can properly store or accommodate the transferred liquefied natural gas, the structure or form thereof is not particularly limited.

If necessary, the pump housing 111 may be provided with an appropriate insulating structure such as a double vacuum insulating method for thermal insulation from the outside.

Meanwhile, the pumping unit 110 may include a connection unit 112 . The connection part 112 may provide a transport path of the liquefied natural gas between the storage tank 10 and the pump housing 111 . The connection part 112 may be implemented in the form of a pipe (官), a pipe (pipe), etc. for the transport of liquefied natural gas, and the structure or shape thereof is not particularly limited.

If necessary, the connection part 112 may have an appropriate thermal insulation structure for thermal insulation from the outside.

Preferably, the connection part 112 may include an upper connection part 112a and a lower connection part 112b. The upper connection part 112a may be connected and installed between the upper gaseous phase region of the storage tank 10 and the upper region of the pump housing 111 , and the lower connection part 112b is the liquid phase region of the storage tank 10 and the lower region and the pump. It may be connected and installed between the lower regions of the housing 111 .

Meanwhile, the pumping unit 110 may include an outlet line 113 . The outlet line 113 may provide a transport path of the liquefied natural gas from the inside of the pump housing 111 to the outside. That is, the liquefied natural gas accommodated in the pump housing 111 may be discharged to the outside through the outlet line 113, and may be provided to a cryogenic liquid storage tank of a vehicle or ship or a predetermined demand. Accordingly, a part of the outlet line 113 may exist inside the pump housing 111 , and the other part may communicate with the outside of the pump housing 111 . The outlet line 113 may be implemented in the form of a pipe, a pipe, etc. for the transport of liquefied natural gas.

If necessary, the outlet line 113 may have an appropriate insulating structure for thermal insulation from the outside.

Meanwhile, the pumping unit 110 may include a suction port 114 . The suction port 114 may include a plurality of suction holes and the like, and may suck the liquefied natural gas accommodated in the pump housing 111 . Alternatively, the suction port 114 may provide a suction path for transferring the liquefied natural gas to the outlet line 113 . The suction port 114 may be any one capable of properly circulating the liquefied natural gas, and the structure or shape thereof is not particularly limited.

As shown, the suction port 114 is generally disposed at the inner lower end of the pump housing 111 . This is in consideration of the stable suction of liquefied natural gas, but the position of the suction port 114 is not necessarily limited thereto. If the suction port 114 is a position that can properly suck the liquefied natural gas contained in the pump housing 111, it can be arranged in various positions, such as the inner side of the pump housing 111, a position spaced upward in the illustrated bar, etc. .

In some cases, the suction port 114 may be modularized or partly accommodated in a predetermined housing, bracket, etc. together with an impeller 115 and a pneumatic motor 116 to be described later.

Meanwhile, the pumping unit 110 may include an impeller 115 . The impeller 115 may generate a suction force for suction of the liquefied natural gas. That is, the impeller 115 may be rotationally driven by a pneumatic motor 116 to be described later to generate a flow flow in the suction direction.

As shown, the impeller 115 is generally exemplified as having a rotation shaft corresponding to the vertical direction or the transport direction of the liquefied natural gas, but the direction of the rotation shaft is not necessarily limited thereto. The impeller 115 is rotationally driven with a predetermined rotation shaft, so long as it can generate a suction force, and the direction of the rotation shaft is not particularly limited.

Meanwhile, the pumping unit 110 may include a pneumatic motor 116 . The pneumatic motor 116 may be disposed inside the pump housing 111 together with the suction port 114 and the impeller 115 . The pneumatic motor 116 may be shaft-coupled to the impeller 115 to rotate the impeller 115 . If necessary, between the pneumatic motor 116 and the impeller 115, an appropriate increase, deceleration means may be added.

In this embodiment, the pneumatic motor 116 may refer to a rotational driving means using the pressure of the gas as a driving source. Here, the pneumatic motor 116 of this embodiment may use some vaporized gas (compressed gas) generated from liquefied natural gas (cryogenic liquid) as a driving source. Compressed gas as a driving source may be provided through a circulation line 121 of the driving unit 120 to be described later.

The above method has an advantage in that heat generation in the pump housing 111 can be reduced. That is, in the case of an electric motor that has been commonly used in the prior art, power is supplied from the outside and driven, and due to the nature of using electricity as a driving source, a considerable amount of heat is inevitably generated. Liquids that are treated as cryogenically, such as liquefied natural gas, may be vaporized due to this heat. In general, since the generated gaseous gas may increase the pressure in the pump housing 111 or the storage tank 10 excessively, when discharged to the atmosphere for safety, a loss has occurred in this process.

On the other hand, in this embodiment, by using the pneumatic motor 116 using the compressed gas as a driving source, it is possible to substantially solve the problems of the prior art. Compressed gas, which is the driving source, can be easily supplied from liquefied natural gas, which is the transported object, and it does not use a device that causes heat such as an electric motor. 111), heat generation can be minimized. Accordingly, the amount of loss due to vaporization during the transfer process can be significantly reduced.

One of the other advantages is that it is very safe compared to conventional electric motors. In the case of an electric motor, the installation of a power line in the pump housing 111 is required to supply power, which is the driving source, and regular repairs are required due to a failure of the pump, or safety against fire and explosion accidents caused by the use of electricity. A high degree of watertight treatment is required to secure it. This is also very expensive in terms of cost. Nevertheless, electric motors always pose a risk of malfunction or explosion due to the nature of the environment in which they are used.

On the other hand, in the case of the present embodiment, since liquefied natural gas or vaporized gas (compressed gas), which is always present in the cryogenic liquid pump 100, is used as a driving source, the above risks can be significantly reduced. The handling of compressed gas, which is the driving source, requires attention and management to the extent of handling liquefied natural gas, which is the existing transport medium, and in reality, most of this can be covered through the configurations of the existing transport system. Accordingly, it can be implemented at a fairly low cost and has high safety.

Other advantages of using compressed gas as a driving source will be further elaborated in each related section.

The pneumatic motor 116 may be rotationally driven by the pressure of the compressed gas as a driving source, and its internal structure or form is not limited to a specific type of pneumatic motor or the like. In a simplified form, the pneumatic motor 116 may be implemented as having a blade having a rotating shaft and a spraying means for providing pressure to the blade.

As shown, the pneumatic motor 116 is generally exemplified as having a rotation shaft corresponding to the vertical direction or the transport direction of the liquefied natural gas, but the direction of the rotation shaft is not necessarily limited thereto. For example, the pneumatic motor 116 may have a rotation axis that is different from the transport direction of the liquefied natural gas or forms a predetermined angle.

In some cases, the pneumatic motor 116 may be integrated with the impeller 115 or may include the impeller 115 as one component. That is, in the present specification, the pneumatic motor 116 and the impeller 115 have been separately illustrated and described for convenience of explanation, but the pneumatic motor 116 and the impeller 115 are not necessarily implemented as separate components. .

Meanwhile, if necessary, the pumping unit 110 may include a safety valve 117 . The safety valve 117 may communicate with the upper end of the pump housing 111 , and may be used to release the pressure inside the pump housing 111 to the atmosphere.

However, as described above, since the cryogenic liquid pump 100 of this embodiment can reduce a significant amount of heat generated in the pump housing 111 through the use of the pneumatic motor 116, the safety valve 117 compared to the prior art. ), the need or frequency of pressure relief can be reduced.

Hereinafter, the driving unit 120 will be described in more detail.

The driving unit 120 may supply compressed gas compressed to the pneumatic motor 116 . As described above, the supplied compressed gas may be used as a rotational driving source of the pneumatic motor 116 to the impeller 115 .

The driving unit 120 basically forms a closed loop and may circulate and supply compressed gas. Compressed gas, which is a driving source, may be circulated to the driving unit 120 after the pressure drops in the pneumatic motor 116 , and the compressed gas may be boosted through the compressor 122 to be provided to the pneumatic motor 116 again.

In some cases, the compressed gas circulating in the driving unit 120 may be replenished in the cryogenic liquid pump 100 . In addition, since the compressed gas is supplied to the pneumatic motor 116 and recovered again, it does not cause a problem due to leakage of a predetermined compressed gas.

Meanwhile, the driving unit 120 may include a circulation line 121 . The circulation line 121 may circulate and supply compressed gas to the pneumatic motor 116 . One end of the circulation line 121 is connected to the pneumatic motor 116 to provide compressed gas of a predetermined pressure for driving the pneumatic motor 116 . The other end of the circulation line 121 is connected to the pneumatic motor 116, and the compressed gas used for driving can be recovered again. The circulation line 121 may provide a flow path of such a compressed gas.

Preferably, the circulation line 121 may be partially or entirely formed in a double insulation structure for insulation from the outside. Alternatively, at least one or more heat insulating means may be provided outside or inside the circulation line 121 .

Meanwhile, the driving unit 120 may include a compressor 122 . The compressor 122 may be installed in the circulation line 121 to pressurize the compressed gas moving in the circulation line 121 to a predetermined pressure. Accordingly, the compressed gas at the rear end of the compressor 122 may have a higher pressure than the compressed gas at the front end of the compressor 122 .

If necessary, the compressor 122 may be controlled to be driven by the controller 122a. The controller 122a may measure the pressure of the buffer tank 123 and control at least one of a discharge pressure, a compression ratio, and a discharge amount of the compressor 122 based on the measured pressure. In the present embodiment, a case in which the control unit 122a is formed to acquire the pressure of the first buffer tank 123a through the sensor means provided in the first buffer tank 123a is exemplified.

Meanwhile, the driving unit 120 may include a buffer tank 123 in the driving unit 120 . The buffer tank 123 may be disposed at the front or rear end of the compressor 122 , and preferably, may be disposed at the rear end of the compressor 122 .

In the present embodiment, a case in which the first buffer tank 123a is disposed at the front end of the compressor 122 and the second buffer tank 123b is disposed at the rear end of the compressor 122 is exemplified. The first and second buffer tanks 123a and 123b may store the compressed gas under a predetermined pressure condition so that the compressed gas of a constant and continuous pressure can be provided to the pneumatic motor 116 .

If necessary, a safety valve 123c may be provided in the second buffer tank 123b at the rear end of the compressor 122 . The safety valve 123c may release the overpressure of the second buffer tank 123b to the atmosphere according to the operating state of the cryogenic liquid pump 100 .

Also, the driving unit 120 may include a regulator 124 . The regulator 124 may adjust the pressure of the compressed gas supplied to the pneumatic motor 116 through the circulation line 121 . In this embodiment, the regulator 124 is disposed at the rear end of the second buffer tank 123b, and the pressure of the compressed gas of the second buffer tank 123b is reduced to a predetermined degree to provide the pneumatic motor 116. . For example, the pressure of the second buffer tank 123b may be 10 to 12 bar, and the regulator 124 may provide it to the pneumatic motor 116 by dropping it to 7 to 8 bar, which is considered to be an appropriate pressure, for example.

In addition, the driving unit 120 may include a flow control valve 125 . The flow rate control valve 125 may adjust the flow rate of the compressed gas supplied to the pneumatic motor 116 . In this embodiment, the flow control valve 125 is disposed at the rear end of the regulator 124 to finally control the flow rate of the compressed gas supplied to the pneumatic motor 116 . Accordingly, it is possible to control the transfer speed of the cryogenic liquid by adjusting the flow rate of the compressed gas. In addition, in some cases, the flow control valve 125 may have a function of turning on/off the cryogenic liquid pump 100 by opening/closing the circulation line 121 .

If necessary, the driving unit 120 may include an emergency valve 126 . The emergency valve 126 may be used to turn off the cryogenic liquid pump 100 or the circulation line 121 when an unexpected special situation occurs. Preferably, the emergency valve 126 may be configured as a manual hand valve, and may be disposed at the rear of the pneumatic motor 116 or in front of the first buffer tank 123a.

If necessary, the driving unit 120 may include a non-return valve 127 . The non-return valve 127 may be used to prevent a reverse flow of the compressed gas in the circulation line 121 . The non-return valve 127 may be configured as a check valve, and as shown in the figure, it is disposed at the immediate front end of the first buffer tank 123a.

FIG. 2 is a modified example of the transport system shown in FIG. 1 .

FIG. 2 shows a different arrangement of the pneumatic motor 116 and the like in the embodiment described above with reference to FIG. 1 . Other components may be formed similarly to those described above.

In the modified example of FIG. 2 , the pneumatic motor 216 may be disposed in the pump housing 211 to have a rotational shaft in the transverse direction. In addition, the impeller 215 may be rotationally driven by being connected to the pneumatic motor 216 by a rotational shaft in the transverse direction. In this case, the liquefied natural gas introduced in the transverse direction through the suction port 214 may be transferred in the longitudinal direction (upper side) by the impeller 215 .

3 is a schematic diagram showing an example of the pneumatic motor shown in FIG.

Referring to FIG. 3 , the pneumatic motor 116 of this embodiment may include a fixed body 116a. The fixed body 116a may have a chamber 116b therein. The chamber 116b may be formed in a generally circular shape in plan view. The fixed body 116a may have a contact surface 116c surrounding the chamber 116b. The contact surface 116c may be formed in a substantially circular shape on a plane to correspond to the shape of the chamber 116b.

In addition, the pneumatic motor 116 of this embodiment may include a rotating body (116d). The rotating body 116d may be disposed in the chamber 116b and may be rotationally driven in the chamber 116b.

The rotating body 116d may include a plurality of vanes 116e. Each vane 116e may be formed to extend radially from the center of the rotating body 116d, and may be fastened to the rotating body 116d to be slidably movable in the radial direction with respect to the center of the rotating body 116d. One end of each vane 116e may be disposed toward the center of the rotating body 116d, and the opposite end may be disposed toward the contact surface 116c. The plurality of vanes 116e may be radially arranged around the rotating body 116d, and this embodiment illustrates four vanes 116e.

Each vane 116e may be moved (in and out) in the radial direction by the centrifugal force of the rotating body 116d. The opposite end of each vane may be intended to be disposed generally in contact with the contact surface 116c. Radial movement of each vane 116e may be achieved by centrifugal force of the rotating body 116d.

On the other hand, the pneumatic motor 116 of this embodiment may include a compressed gas inlet (116f) and a compressed gas outlet (116g). The compressed gas inlet 116f may communicate with one side of the chamber 111a to provide compressed gas to the corresponding vane 116e. The compressed gas outlet 116g may communicate with the other side of the chamber 116b, rotate the vane 116e and discharge the compressed gas to the outside again.

When the compressed gas is provided through the compressed gas inlet 116f to the pneumatic motor 116 as described above, the compressed gas pushes the vane 116e to rotate the rotating body 116d. Here, each vane 116e of the rotating body 116d may maintain a state in contact with the contact surface 116c of the fixed body 116a while being moved in the radial direction by centrifugal force. In addition, the chamber 116b may be partitioned by this, and the rotating body 116d may be rotated using the compressed gas as a driving source.

However, in the cryogenic liquid pump 100 of the present embodiment, the pneumatic motor 116 may be rotationally driven by a predetermined pneumatic pressure, and is not necessarily limited to the structure of the pneumatic motor 116 illustrated above.

FIG. 4 is an operation state diagram of the transport system shown in FIG. 1 .

4, in the cryogenic liquid pump 100 of this embodiment, the liquefied natural gas in the pump housing 111 is introduced through the suction port 114, and the impeller 115 and the pneumatic motor 116 provide an outlet line ( 113) can be transferred.

Here, the pneumatic motor 116 may use a vaporized gas (compressed gas) obtainable from the liquefied natural gas in the cryogenic liquid pump 100 as a driving source. Specifically, the compressed gas flows along the circulation line 121 and may be stored in the first buffer tank 123a, which may be used to protect the pump when a sudden fluid flow occurs according to the operation of the compressor 122. , the second buffer tank 123b functions to store the pressure generated by the compressor 122 to be constantly supplied to the regulator. The compressed gas of the second buffer tank 123b may be provided to the pneumatic motor 116 through the regulator 124 and the flow control valve 125, and the pneumatic motor 116 may be rotationally driven by the pressure of the compressed gas. can

Meanwhile, according to another aspect of the present invention, a method for transferring a cryogenic liquid using the aforementioned cryogenic liquid pump 100 may be provided.

The transfer method according to this embodiment focuses on using the vaporized gas (compressed gas) of the cryogenic liquid as a driving source for transfer, and the technical gist thereof is similar to the cryogenic liquid pump 100 of the above-described embodiment, and the detailed description thereof The description will be omitted.

As described above, in the cryogenic liquid transport system and transport method according to embodiments of the present invention, the vaporization gas (compressed gas) obtained from the cryogenic liquid is used as a driving source for transport. It is possible to effectively reduce the occurrence of vaporization of the cryogenic liquid. Nevertheless, the cryogenic liquid transport system and transport method according to the embodiments of the present invention can be implemented at a relatively low cost, and has a low frequency of failure and high safety compared to conventional schemes such as electric motors.

In the above, although embodiments of the present invention have been described, those of ordinary skill in the art can add, change, delete or add components within the scope that does not depart from the spirit of the present invention described in the claims. The present invention may be variously modified and changed by, etc., and this will also be included within the scope of the present invention.

100: transport system 110: pumping unit
111: pump housing 112: connection part
113: outlet line 114: inlet
115: impeller 116: pneumatic motor
117: safety valve 120: driving unit
121: circulation line 122: compressor
123: buffer tank 124: regulator
125: flow control valve 126: emergency valve
127: non-return valve

Claims (8)

A pumping unit including a pneumatic motor, for transferring the cryogenic liquid of the storage tank to the outside; and
Including; a driving unit for supplying the compressed gas provided from the cryogenic liquid for driving the pneumatic motor;
The driving unit,
a circulation line for providing compressed gas whose pressure and flow rate is adjusted to the pneumatic motor from the rear end of the compressor and recovering the compressed gas used from the pneumatic motor; and
A transport system for cryogenic liquid comprising a; buffer tank provided in the circulation line to temporarily store compressed gas at the front or rear end of the compressor. It relates to a method of transporting a cryogenic liquid using the transport system of claim 1,
A method of transferring cryogenic liquids using compressed gas generated from the cryogenic liquid, which is a transfer object, as a driving source of a pneumatic motor. The method according to claim 1,
The cryogenic liquid,
Containing any one or more of liquefied natural gas (liquefied natural gas), liquid nitrogen, liquefied oxygen, liquid oxygen, liquid helium and liquid carbonic acid, the delivery system of cryogenic liquid. The method according to claim 1,
The pumping unit,
a pump housing having a chamber in which the cryogenic liquid is accommodated;
an outlet line at least partially disposed in the pump housing so that the cryogenic liquid is transferred to the outside of the pump housing;
an inlet through which the cryogenic liquid in the chamber is sucked for transport to the outlet line; and
An impeller rotated by the pneumatic motor to provide suction pressure to the suction port; Containing, a cryogenic liquid conveying system. The method according to claim 1,
The pneumatic motor is
a fixed body having a chamber therein;
a rotating body rotatably disposed inside the chamber; and
A plurality of vanes respectively mounted movably in the radial direction on the rotating body, the vanes being spaced apart from each other in the circumferential direction on the rotating body;
The rotating body is
The compressed gas supplied into the chamber presses each vane and is formed to be rotationally driven about a rotating shaft,
Each vane is
A delivery system for cryogenic liquid, which is moved in a radial direction by the centrifugal force of the rotating body so that a radial end thereof is maintained in contact with a contact surface surrounding the chamber. The method according to claim 1,
The driving unit,
and a flow control valve provided in the circulation line at the rear end of the buffer tank to control the flow rate of the compressed gas provided to the pneumatic motor,
The circulation line is
One side of the rear end of the flow control valve is connected to the pneumatic motor to supply compressed gas, and the other side is connected to the pneumatic motor to recover compressed gas. The method according to claim 1,
The buffer tank is
a first buffer tank in front of the compressor; and
Including; a second buffer tank at the rear end of the compressor;
The driving unit,
Based on the pressure of any one or more of the first and second buffer tanks, comprising a control unit for controlling any one or more of a discharge pressure, a compression ratio, and a discharge amount of the compressor, the cryogenic liquid transport system. 7. The method of claim 6,
The driving unit,
an emergency valve provided in the circulation line to close the circulation line in an emergency;
a non-return valve provided in the circulation line;
a regulator provided in the circulation line between the flow rate control valve and the buffer tank to adjust the pressure of the circulation line; and
A safety valve provided in the buffer tank to release the overpressure to the atmosphere; Containing, a cryogenic liquid transport system.

Images