CN116420044A

CN116420044A - Method for loading and unloading liquefied carbon dioxide and floating body

Info

Publication number: CN116420044A
Application number: CN202180072079.7A
Authority: CN
Inventors: 安部和也; 森本晋介
Original assignee: Mitsubishi Shipbuilding Co Ltd
Current assignee: Mitsubishi Shipbuilding Co Ltd
Priority date: 2020-10-28
Filing date: 2021-10-28
Publication date: 2023-07-11
Also published as: KR20230070023A; WO2022092217A1; AU2021371586A1; JP7365992B2; EP4215798A1; EP4215798A4; JP2022071535A

Abstract

The loading and unloading method of liquefied carbon dioxide comprises the following steps: a step of connecting a connection pipe for connection to an external device disposed outside the floating body to a pipe that communicates with the inside of the tank provided in the floating body; a step of feeding a replacement gas having a moisture content adjusted to be not more than a predetermined upper limit value into the inside of the connection pipe and the pipe to replace the inside of the connection pipe and the pipe with the replacement gas; a step of replacing the inside of the connection pipe and the pipe with carbon dioxide gas from the replacement gas; and a step of loading and unloading liquefied carbon dioxide between the external device and the tank through the connecting pipe and the piping.

Description

Method for loading and unloading liquefied carbon dioxide and floating body

Technical Field

The present invention relates to a method for loading and unloading liquefied carbon dioxide and a floating body.

The present application claims priority based on patent application number 2020-180560 of japanese application at 10/28/2020 and the contents thereof are incorporated herein.

Background

For example, patent document 1 discloses a configuration provided with a transfer device (natural gas transfer device) for transferring liquefied gas from a ship (input ship) provided with a tank for storing the liquefied gas (LNG: liquefied Natural Gas: liquefied natural gas) to an on-land facility (input terminal). In this configuration, the vessel of the plant moored on land is in fluid communication with the plant, delivering the liquefied gas in the tank to the storage tank on land.

Technical literature of the prior art

Patent literature

Patent document 1: japanese patent application laid-open No. 2010-503132

Disclosure of Invention

Technical problem to be solved by the invention

When liquefied gas is loaded into a tank from an external device such as a facility on land or when liquefied gas in the tank is unloaded to the external device, a pipe such as a loading pipe or an unloading pipe provided in the tank is connected to the external device via a connection pipe. However, when the connection pipe is connected to the pipe, air (atmosphere) may intrude into the pipe. When liquefied carbon dioxide is contained in the tank, if air enters the pipe, moisture contained in the air reacts with the carbon dioxide to generate carbonic acid and hydrate. In this way, if carbonic acid and hydrate are formed, corrosion may occur in the piping and the inside of the tank.

Thus, the following process is performed: after connecting a connection pipe to the piping of the tank, carbon dioxide gas is filled into the connection pipe. This suppresses direct contact between the moisture contained in the air and the liquefied carbon dioxide. However, in this case, when filling the carbon dioxide gas, moisture contained in the air in the connection pipe reacts with the carbon dioxide gas, and corrosion may occur in the tank and the pipe.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a liquefied carbon dioxide loading/unloading method and a floating body that can suppress the reaction between carbon dioxide and moisture during loading/unloading of liquefied carbon dioxide and can suppress corrosion of the inside of tanks and pipes.

Means for solving the technical problems

In order to solve the above problems, the method for loading and unloading liquefied carbon dioxide according to the present invention includes a step of connecting a connection pipe, a step of replacing the connection pipe with a replacement gas, a step of replacing the connection pipe with a carbon dioxide gas, and a step of loading and unloading liquefied carbon dioxide. In the step of connecting the connection pipe, the connection pipe is connected to a pipe that communicates with the inside of the tank provided in the floating body. The connection pipe is used for connecting the piping and external equipment arranged outside the floating body. In the step of replacing the gas with the replacement gas, the replacement gas is fed into the connection pipe and the pipe to replace the connection pipe and the pipe with the replacement gas. The water content of the replacement gas is adjusted to be equal to or less than a predetermined upper limit value. In the step of replacing the connecting pipe and the pipe with the carbon dioxide gas, the inside of the connecting pipe and the pipe is replaced with the carbon dioxide gas from the replacement gas. In the step of loading and unloading the liquefied carbon dioxide, the liquefied carbon dioxide is loaded and unloaded between the external device and the tank through the connection pipe and the piping.

The floating body according to the present invention includes a floating body, a tank, a pipe, a replacement gas supply unit, and a carbon dioxide supply unit. The tank is disposed on the floating body. The tank is capable of storing liquefied carbon dioxide. The piping is communicated with the tank. The piping may be connected to a connection pipe for transporting liquefied carbon dioxide between an external device and the tank. When the connection pipe is connected to the pipe, the replacement gas supply unit supplies the replacement gas into the pipe and the connection pipe. The water content of the displacement gas is adjusted to be equal to or less than a predetermined upper limit value. The carbon dioxide supply unit feeds carbon dioxide gas into the pipe and the connection pipe.

Effects of the invention

According to the method for loading and unloading liquefied carbon dioxide and the floating body of the present invention, the carbon dioxide and moisture can be prevented from reacting with each other during loading and unloading of liquefied carbon dioxide, and corrosion of the tank and piping can be prevented from occurring.

Drawings

Fig. 1 is a plan view showing a schematic structure of a ship as a floating body according to an embodiment of the present invention.

Fig. 2 is a view showing tanks and pipes provided in a ship according to an embodiment of the present invention, and is a cross-sectional view taken along the arrow I-I in fig. 1.

Fig. 3 is a view showing tanks and piping provided in a ship according to an embodiment of the present invention, and is a cross-sectional view taken along arrows II-II in fig. 1.

Fig. 4 is a view showing an external device connected to a ship according to an embodiment of the present invention by a connection pipe.

Fig. 5 is a flowchart showing steps of a method for loading and unloading liquefied carbon dioxide according to an embodiment of the present invention.

Fig. 6 is a diagram showing a process of connecting the connection pipes in the method for loading and unloading liquefied carbon dioxide according to the embodiment of the present invention.

Fig. 7 is a diagram showing a process of replacing liquefied carbon dioxide with a replacement gas in the method for loading and unloading liquefied carbon dioxide according to the embodiment of the present invention.

Fig. 8 is a diagram showing a process of replacing the liquefied carbon dioxide gas in the method for loading and unloading the liquefied carbon dioxide according to the embodiment of the present invention.

Fig. 9 is a diagram showing a process of loading and unloading liquefied carbon dioxide in the loading and unloading method of liquefied carbon dioxide according to the embodiment of the present invention.

Detailed Description

Hereinafter, a method for loading and unloading a floating body or liquefied carbon dioxide according to an embodiment of the present invention will be described with reference to fig. 1 to 9.

(Structure of Ship)

As shown in fig. 1 and 2, in the embodiment of the present invention, liquefied carbon dioxide is transported by a ship 1 as a floating body. The ship 1 includes at least a hull 2 as a floating body, a tank facility 10, a replacement gas supply unit 20 (see fig. 2), and a carbon dioxide supply unit 30 (see fig. 2).

(Structure of hull)

The hull 2 has a pair of

sides

3A, 3B, a bottom 4 (see fig. 2), and an upper deck 5, which constitute its outer shell. The

sides

3A, 3B have a pair of side outer plates that form the left and right sides on both sides in the ship width direction Dw, respectively. The bottom 4 is disposed below the vertical Dv and has a bottom outer plate connecting the

sides

3A and 3B. As shown in fig. 2, the hull 2 has a U-shape in cross section orthogonal to the fore-and-aft direction Da by the pair of

side plates

3A, 3B and the bottom 4. The upper deck 5 illustrated in the present embodiment is an all-pass deck exposed to the outside. In the hull 2, an upper deck 5 on the stern 2b side is formed with an upper structure 7 having a living area.

A cargo loading section (cargo hold) 8 is formed in the hull 2 on the bow 2a side of the superstructure 7. The cargo loading section 8 is recessed toward the lower bottom of the upper deck 5 and opens upward.

(construction of tank apparatus)

The tank devices 10 are arranged in plurality in the cargo loading section 8 in the fore-and-aft direction Da. In the embodiment of the present invention, two tank apparatuses 10 are arranged at intervals in the bow-to-stern direction Da.

As shown in fig. 2 and 3, the tank apparatus 10 includes at least a tank 11 and a pipe 12.

In the present embodiment, the tank 11 is disposed on the hull 2. The tank 11 is, for example, cylindrical and extends in the horizontal direction. In the present embodiment, the tanks 11 are arranged with their long axis direction along the bow-to-stern direction Da. Tank 11 contains liquefied carbon dioxide L therein. The tank 11 is not limited to a cylindrical shape, and the tank 11 may be spherical, square, or the like.

The piping 12 includes a loading piping 13 and an unloading piping 14. That is, as the piping 12 of the tank apparatus 10, there are two kinds of loading piping 13 and unloading piping 14.

As shown in fig. 3, the loading pipe 13 forms a pipeline for loading liquefied carbon dioxide L supplied from an external device 100 (see fig. 4) outside the ship, such as liquefied carbon dioxide supply equipment on land, into the tank 11. A part of the loading pipe 13 near one end 13a extends through the top of the tank 11 from the outside to the inside of the tank 11. A portion of the loading pipe 13 near the one end 13a extends in the vertical direction Dv in the tank 11. One end 13a of the loading pipe 13 opens into the tank 11 at the lower portion of the tank 11.

The rest of the loading pipe 13, that is, the portion near the other end 13b is disposed outside the tank 11. As shown in fig. 2, the other end 13b of the loading pipe 13 is provided with a connection portion 13j to the outside of the ship. The connecting portion 13j has, for example, a flange. The coupling portion 13j is disposed toward either one of the

sides

3A, 3B (e.g., the side 3A). The opening of the coupling portion 14j is normally closed by a cover (not shown). The connection portion 13j can be connected to an end portion of the connection pipe 50 for connection to the equipment-side tank 101 of the external equipment 100 by removing the cover (not shown) instead of the cover (not shown).

The off-gas piping 14 sends the liquefied carbon dioxide L in the tank 11 to the external equipment 100 outside the ship. A part of the side of the discharge pipe 14 near the one end 14a penetrates the top of the tank 11 from the outside of the tank 11, and extends into the tank 11. One end 14a of the discharge pipe 14 is disposed in the lower portion of the tank 11. A pump (not shown) is provided at one end 14a of the dump pipe 14. A pump (not shown) sucks liquefied carbon dioxide L in the tank 11 and sends it to the discharge pipe 14. The off-gas piping 14 guides the liquefied carbon dioxide L pumped from the pump to the outside (overboard) of the tank 11.

The portion of the discharge pipe 14 on the side closer to the other end 14b than the other portion is disposed outside the tank 11. As shown in fig. 2, the other end 14b of the off-load piping 14 is provided with a connection portion 14j to the outside of the ship. The coupling portion 14j has, for example, a flange or the like, and is disposed toward either one of the

sides

3A, 3B (for example, the side 3A). The opening of the coupling portion 14j is normally closed by a cover (not shown). The connection portion 14j can be connected to an end portion of the connection pipe 50 for connection to the equipment-side tank 101 of the external equipment 100 by removing the cover (not shown) instead of the cover (not shown).

As shown in fig. 4, when liquefied carbon dioxide L is loaded from the external device 100 into the tank 11, the connection pipe 50 connects the device-side pipe 102 provided in the device-side tank 101 of the external device 100 to the connection portion 13j of the loading pipe 13 so as to communicate with the same. When the liquefied carbon dioxide L is discharged from the tank 11 to the external device 100, the connection pipe 50 connects the device-side pipe 102 provided in the device-side tank 101 of the external device 100 to the connection portion 14j of the discharge pipe 14 so as to communicate with the connection portion. In the following description, except for the case of dividing the loading pipe 13 and the unloading pipe 14, the loading pipe 13 and the unloading pipe 14 are simply referred to as the pipe 12, and the

coupling portions

13j and 14j are simply referred to as the coupling portion 12j.

The pipe 12 and the equipment-side pipe 102 on the external equipment 100 side are provided with on-off

valves

15 and 105, respectively. The on-off valve 15 opens and closes the flow path in the pipe 12. The on-off valve 105 opens and closes the flow path in the equipment-side piping 102. The equipment-side piping 102 is provided with an open valve 106. When the open valve 106 is opened, the flow path in the equipment-side piping 102 communicates with the outside. When the on-off

valves

15 and 105 are closed in a state where the equipment-side piping 102 and the piping 12 are connected by the connection pipe 50, the inside of the piping 12, the connection pipe 50, and the equipment-side piping 102 located between the on-off valve 15 and the on-off valve 105 is not in communication with the equipment-side tank 101 and the tank 11. The outside of the flow path communication in the equipment-side piping 102 is not limited to the atmosphere. For example, the container may be a tank or the like capable of storing the gas released through the open valve 106.

As shown in fig. 2, the replacement gas supply unit 20 supplies the replacement gas Ga into the pipe 12 and the connection pipe 50 in a state where the connection pipe 50 for connection to the external device 100 is connected to the pipe 12. As the substitution gas Ga, a gas that does not chemically react with carbon dioxide may be used. The moisture content of the substitution gas Ga is adjusted to be equal to or less than a predetermined upper limit value. As such a substitution gas Ga, an inert gas such as air (so-called dry air), nitrogen, or argon whose moisture content is adjusted to a predetermined upper limit value or less can be used. In the present embodiment, dry air may be used as the substitution gas Ga. The replacement gas supply unit 20 includes an air dryer 21. The air dryer 21 removes water from the atmosphere taken in from the outside to generate dry air having a water content adjusted to a predetermined upper limit value (for example, a dew point temperature of-40 ℃ or lower). The air dryer 21 is connected to the pipe 12 via a replacement gas supply pipe 22. The replacement gas supply pipe 22 is provided with an on-off valve 23. By opening the on-off valve 23, the dry air generated by the air dryer 21 is sent into the inside of the pipe 12, the connection pipe 50, and the equipment-side pipe 102 through the replacement gas supply pipe 22. The upper limit value of the moisture content in the dry air may be a value that can efficiently remove moisture in the pipe, and may be obtained in advance by an experiment or the like.

As shown in fig. 2 and 4, in a state where the connection pipe 50 for connection to the external device 100 is connected to the pipe 12, the carbon dioxide supply unit 30 supplies carbon dioxide Gc into the pipe 12, the connection pipe 50, and the device-side pipe 102. In the present embodiment, the carbon dioxide supply unit 30 may use the boil-off gas generated by gasifying the liquefied carbon dioxide L in the tank 11 as the carbon dioxide gas Gc. The carbon dioxide supply unit 30 includes a boil-off gas delivery pipe 31 (see fig. 2 and 3). The vapor delivery pipe 31 communicates the upper vapor phase in the tank 11 with the pipe 12. The carbon dioxide supply unit 30 feeds the boil-off gas from the tank 11 through the pipe 12 into the connection pipe 50 and the equipment-side pipe 102.

(step of method for transporting liquefied carbon dioxide)

As shown in fig. 5, the method S10 for loading and unloading liquefied carbon dioxide L according to the present embodiment includes a step S11 of connecting the connection pipe 50, a step S12 of replacing with a replacement gas Ga, a step S13 of replacing with a carbon dioxide gas Gc, and a step S14 of loading and unloading liquefied carbon dioxide L.

In step S11 of connecting the connection pipe 50, as shown in fig. 6, one end of the connection pipe 50 for connection to the external device 100 is connected to the pipe 12. The other end of the connection pipe 50 is connected to the equipment-side pipe 102 of the external equipment 100. At this time, the opening/

closing valves

15, 23, 105 and the opening valve 106 are set in a closed state in advance. In this state, the atmosphere enters the inside of the pipe 12, the connection pipe 50, and the equipment-side pipe 102 located between the on-off valve 15 and the on-off valve 105.

In the step S12 of replacing the gas Ga with the replacement gas, as shown in fig. 7, the replacement gas Ga is fed into the connecting pipe 50 through the replacement gas supply unit 20. For this purpose, the air dryer 21 is operated, the opening/

closing valves

15, 105 are closed, and the opening/closing valve 23 and the opening valve 106 are opened. The air dryer 21 removes moisture from the air (atmosphere) taken in from the outside to produce dry air having a moisture content adjusted to be equal to or less than a predetermined upper limit value, and the dry air becomes the substitution gas Ga. The replacement gas Ga is supplied to the connection portion 12j of the pipe 12 through the replacement gas supply pipe 22. The supplied replacement gas Ga flows from the pipe 12 to the connection pipe 50 and the equipment-side pipe 102, and the air inside the pipe 12, the connection pipe 50, and the equipment-side pipe 102 is sequentially pushed out from the opening valve 106. The dew point of the air discharged from the open valve 106 is measured, and the supply of the replacement gas Ga is continued until the dew point falls within a preset allowable range. After the measured dew point falls within the allowable value range, the supply of the replacement gas Ga by the replacement gas supply unit 20 is stopped, and the open valve 106 and the on-off valve 23 are closed. Thereby, the inside of the pipe 12, the connection pipe 50, and the equipment side pipe 102 between the on-off

valves

15 and 105 is replaced with the replacement gas Ga.

In step S13 of replacing the gas with carbon dioxide gas Gc, the inside of the connection pipe 50 is replaced with carbon dioxide gas Gc from the replacement gas Ga. For this purpose, as shown in fig. 8, the opening/

closing valves

15 and 105 are opened, and the opening valve 106 and the opening/closing valve 23 are closed. In this state, the vaporized gas in the tank 11 is fed into the connecting pipe 50 and the equipment-side pipe 102 through the carbon dioxide supply unit 30 and the pipe 12 as carbon dioxide Gc. Thereby, the replacement gas Ga (dry air) inside the pipe 12, the connection pipe 50, and the equipment-side pipe 102 is sequentially pushed out toward the external equipment 100 side. On the external device 100 side, the carbon dioxide concentration of the mixed gas of the replacement gas Ga and the carbon dioxide gas Gc extruded from the connection pipe 50 side was measured. After the measured carbon dioxide concentration falls within the preset concentration range, the supply of the carbon dioxide gas Gc by the carbon dioxide supply portion 30 is stopped.

In step S14 of loading and unloading liquefied carbon dioxide L, as shown in fig. 9, liquefied carbon dioxide L is loaded and unloaded between external device 100 and tank 11 through connection pipe 50 and pipe 12. For example, in the case of loading liquefied carbon dioxide L into tank 11 from external device 100, liquefied carbon dioxide L is fed into tank 11 from device-side tank 101 of external device 100 through device-side pipe 102, connection pipe 50, and pipe 12 (loading pipe 13).

When the liquefied carbon dioxide L is discharged from the tank 11 to the external device 100, the liquefied carbon dioxide L is fed from the pipe 12 (discharge pipe 14) to the device-side tank 101 of the external device 100 through the connection pipe 50 and the device-side pipe 102.

(effects of action)

According to the liquefied carbon dioxide loading/unloading method S10 of the above embodiment, the inside of the connection pipe 50 and the pipe 12 is replaced with the replacement gas Ga, and then further replaced with the carbon dioxide gas Gc. The moisture content of the substitution gas Ga is adjusted to be equal to or less than a predetermined upper limit value. This suppresses the reaction between the carbon dioxide gas Gc and the moisture when the replacement gas Ga is replaced with the carbon dioxide gas Gc. After replacing the inside of the connection pipe 50 and the pipe 12 with the carbon dioxide gas Gc, the liquefied carbon dioxide L that is loaded and unloaded between the external device 100 and the tank 11 flows into the inside of the connection pipe 50 and the pipe 12, and therefore, the reaction between the carbon dioxide gas Gc and the moisture is also suppressed at this time. Therefore, the reaction of carbon dioxide with moisture during the loading and unloading of liquefied carbon dioxide L can be suppressed, and corrosion of the inside of tank 11 and pipe 12 can be suppressed.

The replacement gas Ga is dry air whose moisture content is adjusted to be equal to or less than a predetermined upper limit value. The dry air used as the replacement gas Ga can be generated by drying the air (atmosphere) by the air dryer 21. Therefore, dry air can be easily prepared on the ship 1.

The carbon dioxide gas Gc is a vaporization gas generated by vaporizing the liquefied carbon dioxide L stored in the tank 11. This makes it possible to easily obtain the carbon dioxide gas Gc on the ship 1.

In the ship 1 of the above embodiment, when the connection pipe 50 for connection to the external device 100 is connected to the pipe 12, the replacement gas Ga whose moisture content is adjusted to be equal to or less than the predetermined upper limit value is fed from the replacement gas supply unit 20 into the connection pipe 50 and the pipe 12. This allows the inside of the connection pipe 50 and the pipe 12 to be replaced with the replacement gas Ga. Further, by feeding the carbon dioxide gas Gc into the connection pipe 50 and the pipe 12 from the carbon dioxide supply unit 30, the inside of the connection pipe 50 and the pipe 12 can be replaced with the carbon dioxide gas Gc from the replacement gas Ga. Then, by attaching and detaching liquefied carbon dioxide L between external device 100 and tank 11 through connection pipe 50 and pipe 12, it is possible to suppress the reaction of carbon dioxide and moisture at the time of attaching and detaching liquefied carbon dioxide L, and to suppress corrosion occurring inside tank 11 and pipe 12.

The ship 1 is also provided with an air dryer 21. As a result, the air dryer 21 dries the air (air) taken in from the outside, whereby dry air having a moisture content adjusted to be not more than a predetermined upper limit value can be supplied as the displacement gas Ga. As a result, the replacement gas Ga whose moisture content is adjusted to be equal to or less than the predetermined upper limit value can be easily obtained from the ship 1.

The vessel 1 also transmits the boil-off gas generated by gasifying the liquefied carbon dioxide L stored in the tank 11 into the pipe 12 and the connection pipe 50 as the carbon dioxide gas Gc. This makes it possible to easily obtain the carbon dioxide gas Gc on the ship 1.

(other embodiments)

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to the embodiments, and design changes and the like within the scope of the present invention are also included.

In the above embodiment, the coupling portion 13j of the loading pipe 13 and the coupling portion 14j of the unloading pipe 14 are provided separately as the coupling portion 12j of the pipe 12, but the present invention is not limited thereto. For example, the loading pipe 13 and the unloading pipe 14 may be connected to one pipe 12 on the other ends 13b, 14b side, and the connecting portion 12j may be shared by the loading pipe 13 and the unloading pipe 14.

In the above embodiment, the liquefied carbon dioxide L is loaded and unloaded between the ship 1 and the external equipment 100 installed on land, but the present invention is not limited to this. The liquefied carbon dioxide L may be loaded and unloaded between the ship 1 and an offshore floating body facility which is arranged on the sea and is not provided with a propulsion mechanism. At this time, the marine floating body installation corresponds to the external installation 100 when viewed from the ship 1.

In the above embodiment, the boil-off gas generated by gasifying the liquefied carbon dioxide L in the tank 11 is used as the carbon dioxide gas Gc, but the carbon dioxide gas Gc may be, for example, carbon dioxide gas or the like contained in another container on the same ship or off-board.

In the ship 1 of the above embodiment, the two tanks 11 are provided, but the number and arrangement of the tanks 11 are not limited to this. More than three tanks 11 may be provided. In the above embodiment, the case where the plurality of tanks 11 are arranged in the fore-and-aft direction Da is illustrated, but the tanks 11 may be arranged in the width direction (in other words, the port-starboard direction). In the above embodiment, the ship 1 is illustrated as the floating body, but the present invention is not limited to this. The floating body may be an offshore floating body installation without propulsion means. In the case where the floating body is an offshore floating body facility, the external facility 100 viewed from the offshore floating body facility may also be a ship.

< additionally remembered >

The method S10 for loading and unloading liquefied carbon dioxide L and the floating body 1 described in the embodiments are grasped as follows, for example.

(1) The method S10 for loading and unloading liquefied carbon dioxide L according to claim 1 includes: a step S11 of connecting a connection pipe 50 for connection to an external device 100 arranged outside the floating body 1 to a pipe 12 communicating with the inside of a tank 11 provided in the floating body 1; a step S12 of feeding a replacement gas Ga having a moisture content adjusted to be equal to or less than a predetermined upper limit value into the connection pipe 50 and the pipe 12 to replace the connection pipe 50 and the pipe 12 with the replacement gas Ga; a step S13 of replacing the inside of the connection pipe 50 and the pipe 12 with carbon dioxide gas Gc from the replacement gas Ga; and a step S14 of loading and unloading liquefied carbon dioxide L between the external device 100 and the tank 11 through the connection pipe 50 and the pipe 12.

As an example of the floating body 1, a ship or an offshore floating body facility can be given. As an example of the floating body 2, a hull or a floating body 2 of an offshore floating body facility can be given.

Examples of the substitution gas Ga include dry air and inert gas.

According to this method S10 for loading and unloading liquefied carbon dioxide L, the inside of the connection pipe 50 and the pipe 12 is replaced with the replacement gas Ga, and then further replaced with the carbon dioxide gas Gc. Since the moisture content of the substitution gas Ga is adjusted to be equal to or less than the predetermined upper limit value, the reaction between carbon dioxide and moisture is suppressed when the substitution gas Ga is substituted by the carbon dioxide Gc. After replacing the inside of the connection pipe 50 and the pipe 12 with the carbon dioxide gas Gc, the liquefied carbon dioxide L that is loaded and unloaded between the external device 100 and the tank 11 flows into the inside of the connection pipe 50 and the pipe 12, and therefore, the reaction between carbon dioxide and moisture is also suppressed from occurring at this time. Therefore, the reaction of carbon dioxide with moisture during the loading and unloading of liquefied carbon dioxide L can be suppressed, and corrosion of the inside of tank 11 and pipe 12 can be suppressed.

(2) The method S10 for loading and unloading liquefied carbon dioxide L according to claim 2 is the method S10 for loading and unloading liquefied carbon dioxide L of (1), wherein the replacement gas Ga is dry air having a moisture content adjusted to be equal to or less than a predetermined upper limit value.

Thereby, the dry air used as the replacement gas Ga can be generated by drying the air (atmosphere) by the air dryer. Therefore, dry air can be easily prepared on the floating body 1.

(3) The method S10 for loading and unloading the liquefied carbon dioxide L according to claim 3 is the method S10 for loading and unloading the liquefied carbon dioxide L according to (1) or (2), wherein the carbon dioxide gas Gc is a vaporization gas generated by vaporizing the liquefied carbon dioxide L stored in the tank 11.

This makes it possible to easily obtain the carbon dioxide gas Gc in the floating body 1.

(4) The floating body 1 according to the 4 th aspect includes: a floating body 2; a tank 11 which is disposed on the floating body 2 and can store liquefied carbon dioxide L; a pipe 12 which communicates with the inside of the tank 11 and can be connected to a connection pipe 50 for transferring liquefied carbon dioxide L between an external device 100 and the tank 11; a replacement gas supply unit 20 that, when the connection pipe 50 is connected to the pipe 12, supplies a replacement gas Ga having a moisture content adjusted to be equal to or less than a predetermined upper limit value into the pipe 12 and the connection pipe 50; and a carbon dioxide supply unit 30 for supplying carbon dioxide gas Gc into the pipe 12 and the connection pipe 50.

In this floating body 1, the replacement gas Ga whose moisture content is adjusted to be equal to or less than a predetermined upper limit value is fed into the connection pipe 50 and the pipe 12 by the replacement gas supply unit 20, whereby the interior of the connection pipe 50 and the pipe 12 can be replaced with the replacement gas Ga. Further, by feeding the carbon dioxide gas Gc into the connection pipe 50 and the pipe 12 from the carbon dioxide supply unit 30, the inside of the connection pipe 50 and the pipe 12 can be replaced with the carbon dioxide gas Gc from the replacement gas Ga. Then, by attaching and detaching liquefied carbon dioxide L between external device 100 and tank 11 through connection pipe 50 and pipe 12, it is possible to suppress the reaction of carbon dioxide and moisture at the time of attaching and detaching liquefied carbon dioxide L, and to suppress corrosion occurring inside tank 11 and pipe 12.

(5) The floating body 1 according to the 5 th aspect is the floating body 1 of (4), wherein the replacement gas supply unit 20 includes an air dryer 21, and the air dryer 21 reduces moisture contained in the atmosphere taken in from the outside.

As a result, the air dryer 21 reduces the moisture contained in the air taken in from the outside, thereby providing the dry air as the substitution gas Ga whose moisture content is adjusted to be equal to or lower than the predetermined upper limit value.

(6) The floating body 1 according to claim 6 is the floating body 1 according to (4) or (5), wherein the carbon dioxide supply unit 30 sends the evaporated gas generated by vaporizing the liquefied carbon dioxide L stored in the tank 11 into the pipe 12 and the connection pipe 50 as the carbon dioxide gas Gc.

Thus, by using the boil-off gas as the carbon dioxide gas Gc, the carbon dioxide gas Gc can be easily obtained on the floating body 1.

Industrial applicability

Symbol description

1-ship (floating body), 2-hull (floating body), 2 a-bow, 2B-stern, 3A, 3B-side, 4-bilge, 5-upper deck, 7-upper structure, 8-cargo loading section, 10-tank equipment, 11-tank, 12-piping, 12 j-connection, 13-loading piping, 13A-one end, 13B-other end, 13 j-connection, 14-unloading piping, 14 a-one end, 14B-other end, 14 j-connection, 15-on-off valve, 20-displacement gas supply, 21-air dryer, 22-displacement gas supply pipe, 23-on-off valve, 30-carbon dioxide supply, 50-connection pipe, 100-external equipment, 101-equipment side tank, 102-equipment side piping, 105-on-off valve, 106-open valve, ga-displacement gas, gc-carbon dioxide gas, L-liquefied carbon dioxide.

Claims

1. A method of loading and unloading liquefied carbon dioxide comprising:

a step of connecting a connection pipe for connection to an external device disposed outside the floating body to a pipe that communicates with the inside of a tank provided in the floating body;

a step of supplying a replacement gas having a moisture content adjusted to be equal to or less than a predetermined upper limit value into the connection pipe and the pipe to replace the connection pipe and the pipe with the replacement gas;

a step of replacing the inside of the connection pipe and the pipe with carbon dioxide gas from the replacement gas; a kind of electronic device with high-pressure air-conditioning system

And a step of loading and unloading liquefied carbon dioxide between the external device and the tank through the connection pipe and the piping.

2. The method for loading and unloading liquefied carbon dioxide according to claim 1, wherein,

the replacement gas is dry air having a moisture content adjusted to be equal to or less than a predetermined upper limit value.

3. The method for loading and unloading liquefied carbon dioxide according to claim 1 or 2, wherein,

the carbon dioxide gas is a vaporization gas generated by vaporizing liquefied carbon dioxide stored in the tank.

4. A floating body, comprising:

a floating body;

a tank which is disposed on the floating body and is capable of storing liquefied carbon dioxide;

a pipe which communicates with the tank and can be connected to a connection pipe for transporting liquefied carbon dioxide between an external device and the tank;

a replacement gas supply unit that, when the connection pipe is connected to the pipe, supplies a replacement gas having a moisture content adjusted to be equal to or less than a predetermined upper limit value into the pipe and the connection pipe; a kind of electronic device with high-pressure air-conditioning system

And a carbon dioxide supply unit for supplying carbon dioxide gas into the pipe and the connection pipe.

5. The floating body of claim 4 wherein,

the replacement gas supply unit is provided with an air dryer that reduces moisture contained in the atmosphere taken in from the outside.

6. The floating body of claim 4 or 5, wherein,

the carbon dioxide supply unit sends, as the carbon dioxide gas, an evaporation gas generated by gasifying liquefied carbon dioxide stored in the tank into the inside of the pipe and the connection pipe.