AU2020415040B2

AU2020415040B2 - Tank system and ship

Info

Publication number: AU2020415040B2
Application number: AU2020415040A
Authority: AU
Inventors: Toshinori Ishida; Shinsuke Morimoto; Toshio Ogata
Original assignee: Mitsubishi Shipbuilding Co Ltd
Current assignee: Mitsubishi Shipbuilding Co Ltd
Priority date: 2019-12-23
Filing date: 2020-12-23
Publication date: 2024-05-02
Anticipated expiration: 2040-12-23
Also published as: EP4059828B1; CN114846265A; JP7221856B2; EP4059828A1; CN114846265B; JP2021099143A; WO2021132381A1; EP4059828A4; AU2020415040A1; KR20220101177A; FI4059828T3

Abstract

A tank system comprises a tank, a loading pipe, and a pipe pressure resistance part. The tank holds liquefied carbon dioxide. The loading pipe extends in a vertical direction, and a bottom end thereof opens into the tank. The loading pipe discharges the liquefied carbon dioxide, which is supplied from the exterior, into the tank from the bottom end. The pipe pressure resistance part is provided closer to the bottom end of the loading pipe than a pipe top part located at the highest point of the loading pipe. The pipe pressure resistance part produces pressure loss in the liquefied carbon dioxide flowing through the loading pipe.

Description

DESCRIPTION

Title of Invention

TANK SYSTEM AND SHIP

Technical Field

[0001]

The present disclosure relates to a tank system and a

ship.

This application claims the right of priority based on

Japanese Patent Application No. 2019-231720 filed with the

Japan Patent Office on December 22, 2019, the content of

which is incorporated herein by reference.

Background Art

[0002]

PTL 1 discloses loading a liquefied gas such as LNG

(Liquefied Natural Gas) into a tank through a gas loading

pipe system.

Citation List

Patent Literature

[0003]

[PTL 1] Japanese Patent No. 5769445

Summary of Invention

Technical Problem

[0004]

Incidentally, there is a demand for carrying liquefied

carbon dioxide by using a tank as in PTL 1. In the liquefied

carbon dioxide, the pressure of a triple point (hereinafter

referred to as triple point pressure) at which a gas phase,

a liquid phase, and a solid phase coexist is higher than

the triple point pressure of LNG or LPG. Therefore, the

triple point pressure becomes close to the operating

pressure of the tank. In a case where the liquefied carbon

dioxide is contained in the tank, for the following reasons,

there is a possibility that the liquefied carbon dioxide

may be solidified to generate dry ice.

[00051

In the tank containing the liquefied gas as in PTL 1,

there is a case where a lower end of a loading pipe, which

is open in the tank, is disposed at a lower portion in the

tank. With such disposition, the vicinity of the opening

of the loading pipe is pressurized with an increase in

liquid head. Therefore, flash evaporation of the liquefied

gas discharged from the opening of the loading pipe can be

suppressed. However, in a pipe top portion disposed at the

highest position of the loading pipe, the pressure of the

liquefied carbon dioxide inside is reduced by the amount

corresponds to the height difference between the pipe lower

end and the pipe top portion with respect to the pressure

of the liquefied carbon dioxide at the pipe lower end.

As a result, depending on the tank operating pressure,

the pressure of the liquefied carbon dioxide becomes equal

to or lower than the triple point pressure in the pipe top

portion of the loading pipe where the pressure of the

liquefied carbon dioxide becomes the lowest, or the

liquefied carbon dioxide evaporates, and due to the

evaporation latent heat thereof, the temperature of the

liquefied carbon dioxide remaining without evaporating is

lowered, so that there is a possibility that the liquefied

carbon dioxide may be solidified to generate dry ice.

Then, in this manner, if dry ice is generated in the

loading pipe, the flow of the liquefied carbon dioxide in

the loading pipe is obstructed, so that there is a

possibility that the operation of the tank may be affected.

[00061

Preferred embodiments of the present invention seek to

provide a tank system and a ship, in which it is possible

to suppress the generation of dry ice in a loading pipe and

smoothly perform the operation of a tank.

[0007]

In accordance with one aspect of the present invention,

there is provided a tank system comprising: a tank that

contains liquefied carbon dioxide therein; a loading pipe

extending in a vertical direction, having a lower end that

is open into the tank, and through which liquefied carbon dioxide that is supplied from an outside of the tank is fed from the lower end into the tank; and a pipe pressure resistance part that is provided close to the lower end with respect to a pipe top portion that is located at a highest position in the loading pipe, and generating a pressure loss in the liquefied carbon dioxide flowing through the loading pipe, wherein the pipe pressure resistance part generates a pressure loss that is determined such that a value obtained by subtracting a pressure corresponding to a height difference between a liquid level of the liquefied carbon dioxide in the tank and the pipe top portion from a value obtained by adding the pressure loss that is generated by the pipe pressure resistance part to a tank operating pressure exceeds a setting pressure lower limit value obtained by adding a safety margin value to a triple point pressure value of the liquefied carbon dioxide.

[0007A]

In accordance with another aspect of the invention,

there is provided a ship comprising: a hull; and the tank

system as described herein, which is provided in the hull.

[00081

A ship according to the present disclosure includes a

hull, and the tank system as described above, which is

provided in the hull.

Advantageous Effects of Invention

[00091

According to the tank system and the ship of the

present disclosure, it is possible to suppress the

generation of dry ice in the loading pipe and smoothly

perform the operation of the tank.

Brief Description of Drawings

[0010]

Fig. 1 is a plan view showing the overall configuration

of a ship in an embodiment of the present disclosure.

Fig. 2 is a sectional view of a tank system provided

in a ship according to a first embodiment of the present

disclosure.

Fig. 3 is a sectional view showing a pipe pressure

resistance part provided in the tank system according to

the first embodiment of the present disclosure.

Fig. 4 is a sectional view showing a pipe pressure

resistance part according to a modification example of the

first embodiment of the present disclosure.

Fig. 5 is a sectional view showing a pipe pressure

resistance part according to a modification example of the

first embodiment of the present disclosure.

Fig. 6 is a sectional view of a tank system provided

in a ship according to a second embodiment of the present

disclosure.

Fig. 7 is a sectional view of a tank system provided in a ship according to a third embodiment of the present disclosure.

Fig. 8 is a sectional view showing a pipe pressure

resistance part provided in the tank system according to

the third embodiment of the present disclosure.

Fig. 9 is a diagram showing a hardware configuration

of a control device provided in the tank system according

to the third embodiment of the present disclosure.

Fig. 10 is a functional block diagram of the control

device provided in the tank system according to the third

embodiment of the present disclosure.

Fig. 11 is a flowchart showing a procedure for opening

degree adjustment processing of a control valve in the

control device provided in the tank system according to the

third embodiment of the present disclosure.

Description of Embodiments

[0011]

Hereinafter, a tank system and a ship according to an

embodiment of the present disclosure will be described with

reference to Figs. 1 to 3.

(Hull Composition of Ship)

As shown in Fig. 1, a ship 1A of an embodiment of the

present disclosure carries liquefied carbon dioxide or

various liquefied gases including liquefied carbon dioxide.

The ship 1A includes at least a hull 2 and a tank system

A.

[0012]

(Configuration of Hull)

The hull 2 has a pair of broadsides 3A and 3B forming

an outer shell thereof, a ship bottom (not shown), and an

upper deck 5. The broadsides 3A and 3B are provided with a

pair of broadside outer plates forming the left and right

broadsides respectively. The ship bottom (not shown) is

provided with a ship bottom outer plate connecting the

broadsides 3A and 3B. Due to the pair of broadsides 3A and

3B and the ship bottom (not shown), the outer shell of the

hull 2 has a U-shape in a cross-section orthogonal to a bow

stern direction Da. The upper deck 5 is an all-deck that

is exposed to the outside. In the hull 2, a superstructure

7 having an accommodation space is formed on the upper deck

on the stern 2b side.

[0013]

In the hull 2, a tank system storage compartment (a

hold) 8 is formed on the bow 2a side with respect to the

superstructure (the accommodation space) 7. The tank system

storage compartment 8 is a closed compartment that is

recessed toward the ship bottom (not shown) below the upper

deck 5 and protrudes upward or has the upper deck 5 as a

ceiling.

[00141

(Composition of Tank System)

As shown in Fig. 2, the tank system 20A includes a

tank 21, a loading pipe 25, and a pipe pressure resistance

part 30A.

[0015]

(Configuration of Tank)

As shown in Fig. 1, a plurality of tanks 21 are

provided in the tank system storage compartment 8. In this

embodiment, for example, a total of seven tanks 21 are

provided in the tank system storage compartment 8. The

layout and the number of tanks 21 installed in the tank

system storage compartment 8 are not limited in any way.

In this embodiment, each tank 21 has, for example, a

cylindrical shape extending in the horizontal direction

(specifically, the bow-stern direction). The tank 21

contains liquefied carbon dioxide L inside.

The tank 21 is not limited to a cylindrical shape, and

the tank 21 may be a spherical shape or the like.

[0016]

(Configuration of Loading Pipe)

As shown in Fig. 2, the loading pipe 25 loads the

liquefied carbon dioxide L, which is supplied from the

outside such as a liquefied carbon dioxide supply facility

on land or a bunker ship, into the tank 21. The loading pipe 25 in this embodiment is inserted into the tank 21 by penetrating the upper portion of the tank 21 from the outside of the tank 21. The loading pipe 25 extends in an up-down direction Dv in the tank 21. A lower end 25b of the loading pipe 25 is open in the tank 21. The loading pipe 25 discharges the liquefied carbon dioxide L that is supplied from the outside into the tank 21 from the lower end 25b. In the loading pipe 25, a pipe top portion 25t that is located at the highest position is disposed outside the tank 21.

[0017]

The lower end 25b of the loading pipe 25 is disposed

in the vicinity of a bottom portion of the tank 21. The

vicinity of the bottom portion is a position closer to the

bottom portion than the center of the tank 21 in the up

down direction Dv. Fig. 2 illustrates a situation in which

the lower end 25b of the loading pipe 25 is submerged in

the liquefied carbon dioxide L stored in the tank 21.

Further, in Fig. 2, the lower end 25b is open downward.

However, the opening direction thereof is not limited to

the downward direction.

[0018]

(Configuration of Pipe Pressure Resistance Part)

The pipe pressure resistance part 30A acts as a pipe

pressure resistance on the liquefied carbon dioxide L flowing through the loading pipe 25. The pipe pressure resistance part 30A is provided on the lower end 25b side with respect to the pipe top portion 25t which is located at the highest position in the loading pipe 25. In this embodiment, the pipe pressure resistance part 30A is provided at the lower end 25b of the loading pipe 25.

However, there is no limitation to the lower end 25b. As

shown in Fig. 3, the pipe pressure resistance part 30A has

a flow opening portion 30a through which the liquefied

carbon dioxide L flows. The flow opening portion 30a has

an opening area A2 smaller than a flow path cross-sectional

area Al in the loading pipe 25.

[0019]

In this embodiment, the pipe pressure resistance part

A is configured using an orifice 31. The orifice 31 is

mounted to the lower end 25b of the loading pipe 25. The

orifice 31 includes a plate portion 31a provided so as to

close the opening of the lower end 25b of the loading pipe

, and a through-hole 31b formed in the plate portion 31a.

The through-hole 31b forms the flow opening portion 30a.

The through-hole 31b is formed to penetrate in a plate

thickness direction of the plate portion 31a (a pipe axis

direction at the lower end 25b of the loading pipe 25). In

this embodiment, only one through-hole 31b is formed in the

central portion of the plate portion 31a.

[00201

A pressure Pc in the pipe top portion 25t of the

liquefied carbon dioxide L flowing through the loading pipe

having the pipe pressure resistance part 30A provided at

the lower end 25b has a value obtained by subtracting a

pressure corresponding to the height difference between the

liquid level of the liquefied carbon dioxide L in the tank

21 and the pipe top portion 25t from a value obtained by

adding a pressure loss AP that is generated by the pipe

pressure resistance part to a tank operating pressure Pt.

However, in a case where the dynamic pressure of the

liquefied carbon dioxide L flowing through the loading pipe

is significant, it is necessary to consider the influence

thereof.

[0021]

In order to prevent the liquefied carbon dioxide L

from falling below the triple point pressure of the

liquefied carbon dioxide L in the pipe top portion 25t of

the loading pipe 25, the pressure Pc of the liquefied carbon

dioxide L in the pipe top portion 25t needs to exceed a

setting pressure lower limit value Ps of the liquefied

carbon dioxide L set in advance, as in the following

expression (1).

Pc > Ps ... (1)

Here, the setting pressure lower limit value Ps can be a value obtained by adding a safety margin value to the triple point pressure value of the liquefied carbon dioxide

L.

[0022]

In the pipe pressure resistance part 30A (the orifice

31), the opening area A2 of the flow opening portion 30a is

set so as to satisfy the condition expressed by the above

expression (1) by utilizing the fact that the generated

pressure loss AP increases the pressure Pc in the pipe top

portion 25t.

[0023]

(Specific Study Example)

Here, for example, the operating pressure of the tank

21 is set to be 580 [kPa(G)], the density p of the liquefied

carbon dioxide L is set to be 1150 [kg/m 3 ], a liquid level

height Hi of the liquefied carbon dioxide L in the tank 21

is set to be 0 [m], and a height H2 of the pipe top portion

t of the loading pipe 25 from a tank bottom surface 21b

is set to be 30 [m]. Then, the pressure of the liquefied

carbon dioxide L in the pipe top portion 25t of the loading

pipe 25 in a state of having no pipe pressure resistance

part 30A becomes 242 [kPa(G)]. The triple point pressure

of the liquefied carbon dioxide L is 417 [kPa(G)], and

therefore, in a state where the pipe pressure resistance

part 30A is not provided, the pressure of the liquefied carbon dioxide L in the pipe top portion 25t of the loading pipe 25 becomes equal to or lower than the triple point pressure, and thus there is a possibility that dry ice may be generated.

In contrast, in the loading pipe 25 provided with the

pipe pressure resistance part 30A, the pressure loss AP is

generated by the pipe pressure resistance part 30A so as to

satisfy the above expression (1), and the pressure Pc of

the liquefied carbon dioxide L in the pipe top portion 25t

always exceeds the setting pressure lower limit value Ps,

and can sufficiently exceed the triple point pressure.

[00241

(Operation and Effects)

The tank system 20A of the first embodiment includes

the tank 21, the loading pipe 25, and the pipe pressure

resistance part 30A. The pipe pressure resistance part 30A

is provided on the lower end 25b side with respect to the

pipe top portion 25t that is located at the highest position

in the loading pipe 25. Due to the pipe pressure resistance

part 30A, the pressure of the liquefied carbon dioxide L

flowing through the loading pipe 25 is increased by the

amount corresponding to the pressure loss AP, and the

pressure Pc of the liquefied carbon dioxide L is restrained

from approaching the triple point pressure. In this way,

it is possible to suppress the generation of dry ice due to solidification of the liquefied carbon dioxide L in the loading pipe 25. As a result, in a case where the liquefied carbon dioxide L is contained in the tank 21, it becomes possible to suppress the generation of dry ice in the loading pipe 25 and smoothly perform the operation of the tank 21.

[0025]

In the tank system 20A of the first embodiment, the

pipe pressure resistance part 30A generates the pressure

loss AP satisfying the above expression (1).

Therefore, according to the tank system 20A of the

embodiment, an appropriate pressure loss AP according to

the height H2 of the pipe top portion 25t of the loading

pipe 25 is generated by the pipe pressure resistance part

A to be able to increase the pressure of the liquefied

carbon dioxide L. In this way, the pressure of the liquefied

carbon dioxide L becomes equal to or higher than the setting

pressure lower limit value Ps set according to the triple

point pressure of the liquefied carbon dioxide L in the

entire area in the loading pipe 25. In this way, it is

possible to suppress the generation of dry ice in the

loading pipe 25.

[0026]

In the tank system 20A of the first embodiment, the

pipe pressure resistance part 30A is provided at the lower end 25b of the loading pipe 25.

Therefore, according to the tank system 20A of the

embodiment, due to the pipe pressure resistance part 30A

provided at the lower end 25b of the loading pipe 25, the

generation of dry ice in the loading pipe 25 is suppressed.

Further, the pipe pressure resistance part 30A can be

additionally provided even with respect to the lower end

b of the loading pipe 25 of the existing tank system 20A.

[00271

In the tank system 20A of the first embodiment, the

pipe pressure resistance part 30A (the orifice 31) has the

flow opening portion 30a which has the opening area A2

smaller than the flow path cross-sectional area Al in the

loading pipe 25 and through which the liquefied carbon

dioxide L flows.

The pipe pressure resistance part 30A as described

above has a simple configuration having the flow opening

portion 30a, and can realize suppression of the generation

of dry ice in liquefied carbon dioxide L at low cost.

[0028]

The ship 1A of the first embodiment includes the hull

2 and the tank system 20A provided in the hull 2.

Therefore, according to the ship 1A of the embodiment,

it is possible to provide the ship 1A provided with the tank

system 20A in which in a case where the liquefied carbon dioxide L is contained in the tank 21, the generation of dry ice in the loading pipe 25 is suppressed and the operation of the tank 21 can be performed smoothly.

[00291

In the first embodiment, a configuration is made in

which the orifice 31 is provided as the pipe pressure

resistance part 30A. However, there is no limitation

thereto.

For example, as shown in Fig. 4, a perforated plate 32

may be provided as the pipe pressure resistance part 30A.

The perforated plate 32 is mounted to the lower end 25b of

the loading pipe 25. The perforated plate 32 includes a

plate portion 32a provided so as to close the opening of

the lower end 25b of the loading pipe 25, and a plurality

of (many) through-holes 32b formed in the plate portion 32a.

Each of the through-holes 32b penetrates in the plate

thickness direction of the plate portion 32a. The flow

opening portion 30a is configured by the plurality of

through-holes 32b. In the flow opening portion 30a, a total

opening area A3 of the plurality of through-holes 32b is

smaller than the flow path cross-sectional area Al in the

loading pipe 25.

The pipe pressure resistance part 30A using the

perforated plate 32 as described above can increase the pressure of the liquefied carbon dioxide L flowing through the loading pipe 25 by the amount corresponding to the pressure loss AP.

[00301

Further, as shown in Fig. 5, a flap 33 may be provided

as the pipe pressure resistance part 30A. The flap 33 is

mounted on the inside of the lower end 25b of the loading

pipe 25. The flap 33 has a plate shape and is provided to

be inclined with respect to a plane orthogonal to a pipe

axis direction Dp at the lower end 25b of the loading pipe

25. The flap 33 is provided to have a gap 33b between an

outer peripheral edge 33a thereof and an inner peripheral

surface 25f of the lower end 25b of the loading pipe 25.

The gap 33b between the outer peripheral edge 33a of the

flap 33 and the inner peripheral surface 25f of the loading

pipe 25 forms the flow opening portion 30a. An opening area

A4 of the gap 33b forming the flow opening portion 30a is

smaller than the flow path cross-sectional area Al in the

loading pipe 25.

The pipe pressure resistance part 30A using the flap

33 as described above can increase the pressure of the

liquefied carbon dioxide L flowing through the loading pipe

by the amount corresponding to the pressure loss AP.

[0031]

Next, a tank system and a ship according to a second

embodiment of the present disclosure will be described with

reference to Fig. 6. In the second embodiment of the present

disclosure that is described below, only the position of a

pipe pressure resistance part 30B is different from that in

the first embodiment of the present disclosure, and

therefore, the same portions as those in the first

embodiment will be denoted by the same reference numerals,

and overlapping description will be omitted.

(Hull Composition of Ship)

As shown in Fig. 1, a ship 1B of this embodiment

carries liquefied carbon dioxide or various liquefied gases

including liquefied carbon dioxide. The ship 1B includes

at least the hull 2 and a tank system 20B.

[00321

(Composition of Tank System)

As shown in Fig. 6, the tank system 20B includes the

tank 21, the loading pipe 25, and the pipe pressure

resistance part 30B.

[00331

(Configuration of Pipe Pressure Resistance Part)

The pipe pressure resistance part 30B can increase the

pressure of the liquefied carbon dioxide L flowing through

the loading pipe 25 by the amount corresponding to the

pressure loss. The pipe pressure resistance part 30B is provided on the lower end 25b side with respect to the pipe top portion 25t that is located at the highest position in the loading pipe 25. In the second embodiment, the pipe pressure resistance part 30B is provided between the pipe top portion 25t and the lower end 25b of the loading pipe

25. The pipe pressure resistance part 30B is provided at a

position higher than the lower end 25b of the loading pipe

25.

The pipe pressure resistance part 30B is formed using

one of the orifice 31 (refer to Fig. 3), the perforated

plate 32 (refer to Fig. 4), and the flap 33 (refer to Fig.

) shown in the first embodiment. The pipe pressure

resistance part 30B is provided such that the generated

pressure loss AP satisfies the condition expressed by the

above expression (1).

[00341

Further, in a case where the pipe pressure resistance

part 30B is provided at a position higher than the lower

end 25b of the loading pipe 25, it is necessary to prevent

the pressure of the liquefied carbon dioxide L that has

passed through the pipe pressure resistance part 30B from

falling below the triple point pressure on the lower side

(the lower end 25b side) of the pipe pressure resistance

part 30B.

Therefore, in a case where the pipe pressure resistance part 30B is provided at a height H [mm] from the tank bottom surface 21b of the tank 21, it is necessary to make the pressure of the liquefied carbon dioxide L at the height H of the pipe pressure resistance part 30B exceed the setting pressure lower limit value Ps.

[0035]

The height H [mm] from the tank bottom surface 21b

where the pipe pressure resistance part 30B is installed is

limited such that the pressure of the liquefied carbon

dioxide L passing through the pipe pressure resistance part

B does not fall below the triple point pressure, in

consideration of the fact that the pressure of the liquefied

carbon dioxide L decreases according to the height

difference between the height H and the liquid level height

Hi of the liquefied carbon dioxide L in the tank 21.

[0036]

(Operation and Effects)

The tank system 20B of the second embodiment includes

the tank 21, the loading pipe 25, and the pipe pressure

resistance part 30B. The pipe pressure resistance part 30B

is provided on the lower end 25b side with respect to the

pipe top portion 25t that is located at the highest position

in the loading pipe 25. Due to the pipe pressure resistance

part 30B, the pressure of the liquefied carbon dioxide L

flowing through the loading pipe 25 is increased by the amount corresponding to the pressure loss AP, and the pressure Pc of the liquefied carbon dioxide L is restrained from approaching the triple point pressure. As a result, in a case where the liquefied carbon dioxide L is contained in the tank 21, it becomes possible to suppress the generation of dry ice in the loading pipe 25 and smoothly perform the operation of the tank 21.

[00371

In the tank system 20B of the second embodiment, the

pipe pressure resistance part 30B generates the pressure

loss AP satisfying the above expression (1).

Therefore, according to the tank system 20B of the

embodiment, an appropriate pressure loss AP according to

the height H2 of the pipe top portion 25t of the loading

pipe 25 is generated by the pipe pressure resistance part

B to be able to increase the pressure of the liquefied

carbon dioxide L. In this way, it is possible to suppress

the generation of dry ice due to solidification of the

liquefied carbon dioxide L in the loading pipe 25.

[00381

In the tank system 20B of the second embodiment, the

pipe pressure resistance part 30B is higher than the lower

end 25b of the loading pipe 25, and the height H [mm] thereof

from the tank bottom surface 21b of the tank 21 is limited

such that the pressure of the liquefied carbon dioxide L that has passed through the pipe pressure resistance part

B does not fall below the triple point pressure, in

consideration of the fact that the pressure of the liquefied

carbon dioxide L decreases according to the height

difference between the height H from the tank bottom surface

21b and the liquid level height Hi of the liquefied carbon

dioxide L in the tank 21.

Therefore, according to the tank system 20B of the

embodiment, the pressure of the liquefied carbon dioxide L

becomes equal to or higher than the setting pressure lower

limit value Ps on the lower side (the lower end 25b side)

with respect to the pipe pressure resistance part 30B. In

this way, it is possible to suppress the generation of dry

ice due to the occurrence of a pressure drop of the liquefied

carbon dioxide L that has passed through the pipe pressure

resistance part 30B.

[00391

The ship 1B of the second embodiment includes the hull

2 and the tank system 20B provided in the hull 2.

Therefore, according to the ship 1B of the second

embodiment, it is possible to provide the ship 1B provided

with the tank system 20B in which in a case where the

liquefied carbon dioxide L is contained in the tank 21, the

generation of dry ice in the loading pipe 25 is suppressed

and the operation of the tank 21 can be performed smoothly.

[0040]

[Third Embodiment]

Next, a tank system and a ship according to a third

embodiment of the present disclosure will be described with

reference to Figs. 7 to 11. In the third embodiment of the

present disclosure that is described below, only the

configuration of a pipe pressure resistance part 30C is

different from those in the first and second embodiments of

the present disclosure, and therefore, the same portions as

those in the first and second embodiments will be denoted

by the same reference numerals, and overlapping description

will be omitted.

(Hull Composition of Ship)

As shown in Fig. 1, a ship 1C of this embodiment

carries liquefied carbon dioxide or various liquefied gases

including liquefied carbon dioxide. The ship 1C includes

at least the hull 2 and a tank system 20C.

[0041]

(Composition of Tank System)

As shown in Fig. 7, the tank system 20C includes the

tank 21, the loading pipe 25, and a pipe pressure resistance

part 30C.

[0042]

(Configuration of Pipe Pressure Resistance Part)

The pipe pressure resistance part 30C can increase the pressure of the liquefied carbon dioxide L flowing through the loading pipe 25 by the amount corresponding to the pressure loss. In this embodiment, the pipe pressure resistance part 30C includes a control valve 35 and a control device 60.

[0043]

The control valve 35 of the pipe pressure resistance

part 30C is provided on the lower end 25b side with respect

to the pipe top portion 25t that is located at the highest

position in the loading pipe 25. In the third embodiment,

the control valve 35 is provided at the lower end 25b of

the loading pipe 25. The control valve 35 may be provided

at a position higher than the lower end 25b of the loading

pipe 25, as in the second embodiment.

[0044]

The control valve 35 shown in Fig. 8 makes an opening

area A5 of the flow opening portion 30a variable. The

control valve 35 has a valve body 35a rotatably provided in

the flow path of the liquefied carbon dioxide L in the

loading pipe 25. The valve body 35a opens and closes the

flow path in the loading pipe 25 by rotating around a valve

shaft. The valve body 35a increases or decreases a gap 35b

formed between the valve body 35a and the inner peripheral

surface 25f of the loading pipe 25 by adjusting the opening

degree around the valve shaft. The gap 35b between the valve body 35a and the inner peripheral surface 25f of the loading pipe 25 forms the flow opening portion 30a. The opening area A5 of the gap 35b forming the flow opening portion 30a is smaller than the flow path cross-sectional area Al in the loading pipe 25. As the control valve 35, it is preferable to use a submersible low-temperature resistant valve that can operate even in the liquefied carbon dioxide L having a low-temperature.

The pipe pressure resistance part 30C using the

control valve 35 as described above can increase the

pressure of the liquefied carbon dioxide L flowing through

the loading pipe 25 by the amount corresponding to the

pressure loss AP.

[0045]

In the control valve 35 of the pipe pressure resistance

part 30C, the opening area A5 of the flow opening portion

a is set so as to satisfy the condition expressed by the

above expression (1) by utilizing the fact that the

generated pressure loss AP increases the pressure Pc in the

pipe top portion 25t.

[0046]

(Configuration of Control Device)

The control device 60 adjusts the opening degree of

the flow opening portion 30a in the control valve 35. In

order to adjust the opening degree of the control valve 35 by the control device 60, the tank system 20C includes a tank internal pressure sensor 51 and a pipe top portion pressure sensor 52. The tank internal pressure sensor 51 detects the internal pressure of the tank 21. The pipe top portion pressure sensor 52 detects the pressure Pc of the liquefied carbon dioxide L in the pipe top portion 25t.

[0047]

(Hardware Configuration Diagram of Control Device)

As shown in Fig. 9, the control device 60 is a computer

that includes a CPU 61 (Central Processing Unit), a ROM 62

(Read Only Memory), a RAM 63 (Random Access Memory), an HDD

64 (Hard Disk Drive), and a signal receiving module 65. The

signal receiving module 65 receives the detection signals

from the tank internal pressure sensor 51 and the pipe top

portion pressure sensor 52.

[0048]

(Functional Block Diagram of Control Device)

As shown in Fig. 10, the CPU 61 of the control device

executes a program stored in the HDD 64, the ROM 62, or

the like in advance to realize a functional configuration

of each of a signal receiving unit 71, an opening degree

control unit 72, and a command signal output unit 73.

The signal receiving unit 71 receives the detection

signals from the tank internal pressure sensor 51 and the

pipe top portion pressure sensor 52, that is, the data of the detection value of the internal pressure of the tank 21 in the tank internal pressure sensor 51 and the detection value of the pressure Pc of the liquefied carbon dioxide L in the pipe top portion 25t, through the signal receiving module 65.

The opening degree control unit 72 executes control

for adjusting the opening degree of the control valve 35,

based on the detection value in the pipe top portion

pressure sensor 52.

The command signal output unit 73 outputs a command

signal for changing the opening degree of the control valve

to the control valve 35 under the control of the opening

degree control unit 72.

[0049]

(Processing Procedure)

Next, a procedure for adjusting the opening degree of

the control valve 35 by the control device 60 in the tank

system 20C will be described.

As shown in Fig. 11, the signal receiving unit 71 of

the control device 60 receives the data of the detection

value of the internal pressure (the operating pressure Pt)

of the tank 21 in the tank internal pressure sensor 51 and

the detection value of the pressure Pc of the liquefied

carbon dioxide L in the pipe top portion 25t from the tank

internal pressure sensor 51 and the pipe top portion pressure sensor 52 at time intervals set in advance (step

Si).

[00501

Subsequently, the opening degree control unit 72

determines whether or not the pressure Pc of the liquefied

carbon dioxide L in the pipe top portion 25t received in

step S1 is lower than a threshold value set in advance (for

example, the setting pressure lower limit value Ps) (step

S2). As a result, if the pressure Pc of the liquefied

carbon dioxide L in the pipe top portion 25t is not lower

than the threshold value, the processing returns to step S1.

[0051]

In step S2, in a case where the pressure Pc of the

liquefied carbon dioxide L in the pipe top portion 25t is

lower than the threshold value, that is, in a case where

the pressure Pc of the liquefied carbon dioxide L in the

pipe top portion 25t is lower than the setting pressure

lower limit value Ps, the opening degree control unit 72

reduces the opening degree of the control valve 35 (step

S3). To this end, the opening degree control unit 72 outputs

a command signal for reducing the opening degree of the

valve body 35a by a predetermined angle to the control valve

through the command signal output unit 73. After

outputting the command signal, the control device 60 ends

the processing and returns to step S1.

[00521

(Operation and Effects)

The tank system 20C of the above embodiment includes

the tank 21, the loading pipe 25, and the pipe pressure

resistance part 30C. Further, the pipe pressure resistance

part 30C is provided on the lower end 25b side with respect

to the pipe top portion 25t that is located at the highest

position in the loading pipe 25. Due to the pipe pressure

resistance part 30C, the pressure of the liquefied carbon

dioxide L flowing through the loading pipe 25 is increased

by the amount corresponding to the pressure loss AP, and

the pressure Pc of the liquefied carbon dioxide L is

restrained from approaching the triple point pressure. As

a result, in a case where the liquefied carbon dioxide L is

contained in the tank 21, it becomes possible to suppress

the generation of dry ice in the loading pipe 25 and smoothly

perform the operation of the tank 21.

[00531

In the tank system 20C of the above embodiment, the

pipe pressure resistance part 30C generates the pressure

loss AP satisfying the above expression (1).

Therefore, according to the tank system 20C of the

embodiment, an appropriate pressure loss AP according to

the height H2 of the pipe top portion 25t of the loading

pipe 25 is generated by the pipe pressure resistance part

C to be able to increase the pressure of the liquefied

carbon dioxide L. In this way, it is possible to suppress

the generation of dry ice due to solidification of the

liquefied carbon dioxide L in the loading pipe 25.

[00541

In the tank system 20C of the above embodiment, the

pipe pressure resistance part 30C has the flow opening

portion 30a which has the opening area A5 smaller than the

flow path cross-sectional area Al in the loading pipe 25

and through which the liquefied carbon dioxide L flows.

The pipe pressure resistance part 30C as described

above has a simple configuration having the flow opening

portion 30a, and can realize suppression of the generation

of dry ice in the liquefied carbon dioxide L at low cost.

[00551

In the tank system 20C of the above embodiment, the

pipe pressure resistance part 30C includes the control valve

that makes the opening area A5 of the flow opening portion

a variable, and the control device 60 that adjusts the

opening degree of the flow opening portion 30a in the

control valve 35.

Therefore, according to the tank system 20C of the

embodiment, the pressure loss AP that is generated by the

pipe pressure resistance part 30C can be adjusted by

adjusting the opening degree of the flow opening portion a in the control valve 35 by the control device 60. In this way, it becomes possible to appropriately adjust the pressure loss AP that increases the pressure of the liquefied carbon dioxide L according to the operating condition or the like of the tank system 20C.

[00561

The tank system 20C of the above embodiment further

includes the pipe top portion pressure sensor 52 that

detects the pressure Pc of the liquefied carbon dioxide L

in the pipe top portion 25t of the loading pipe 25, and the

control device 60 adjusts the opening degree of the control

valve 35, based on the detection value in the pipe top

portion pressure sensor 52.

Therefore, according to the tank system 20C of the

embodiment, the pressure loss AP that increases the pressure

of the liquefied carbon dioxide L flowing through the

loading pipe 25 can be adjusted at the pipe pressure

resistance part 30C according to the pressure Pc of the

liquefied carbon dioxide L in the pipe top portion 25t

detected by the pipe top portion pressure sensor 52.

Therefore, it becomes possible to appropriately adjust the

pressure loss AP that increases the pressure of the

liquefied carbon dioxide L such that the pressure of the

liquefied carbon dioxide L in the pipe top portion 25t does

not fall below the setting pressure lower limit value Ps.

[00571

The ship 1C of the above embodiment includes the hull

2 and the tank system 20C provided in the hull 2.

Therefore, according to the ship 1C of the embodiment,

it is possible to provide the ship 1C provided with the tank

system 20C in which in a case where the liquefied carbon

dioxide L is contained in the tank 21, the generation of

dry ice in the loading pipe 25 is suppressed and the

operation of the tank 21 can be performed smoothly.

[00581

The embodiments of the present disclosure have been

described in detail above with reference to the drawings.

However, the specific configurations are not limited to the

embodiments, and also include design changes or the like

within a scope which does not deviate from the gist of the

present disclosure.

In the embodiments described above, a configuration is

made in which the tank 21 is provided in the tank system

storage compartment 8 formed in the hull 2. However, there

is no limitation thereto, and for example, the tank 21 is

provided on the upper deck 5.

Further, in the embodiments described above, the tank

21 is provided in the ship 1A, 1B, or 1C. However, there

is no limitation thereto, and, for example, the tank 21 may be installed in a place other than the ships 1A to 1C, for example, on land or in marine facility, or in a vehicle such as a tank lorry.

[00591

The tank systems 20A, 20B, and 20C and the ships 1A to

1C described in the embodiment are grasped as follows, for

example.

[00601

(1) The tank system 20A, 20B, or 20C according to a

first aspect includes the tank 21 that contains the

liquefied carbon dioxide L therein, the loading pipe 25 that

extends in the up-down direction Dv, has the lower end 25b

that is open into the tank 21, and discharges the liquefied

carbon dioxide L that is supplied from the outside, from

the lower end 25b into the tank 21, and the pipe pressure

resistance part 30A, 30B, or 30C that is provided on the

lower end 25b side with respect to the pipe top portion 25t

that is located at the highest position in the loading pipe

, and generates the pressure loss AP in the liquefied

carbon dioxide L flowing through the loading pipe 25.

As an example of the pipe pressure resistance part 30A,

B, or 30C, there is the orifice 31, the perforated plate

32, or the flap 33.

[00611

In the tank system 20A, 20B, or 20C, due to the pipe

pressure resistance part 30A, 30B, or 30C, the pressure of

the liquefied carbon dioxide L flowing through the loading

pipe 25 is increased by the amount corresponding to the

pressure loss AP. The pressure Pc of the liquefied carbon

dioxide L in the pipe top portion 25t of the loading pipe

is increased, so that the pressure Pc of the liquefied

carbon dioxide L is restrained from approaching the triple

point pressure. In this way, it is possible to suppress

the generation of dry ice due to solidification of the

liquefied carbon dioxide L in the loading pipe 25. As a

result, in a case where the liquefied carbon dioxide L is

contained in the tank 21, it becomes possible to suppress

the generation of dry ice in the loading pipe 25 and smoothly

perform the operation of the tank 21.

[0062]

(2) In the tank system 20A, 20B, or 20C according to

a second aspect, in the tank system 20A, 20B, or 20C of the

above (1), the pipe pressure resistance part 30A, 30B, or

C generates the pressure loss AP that is determined such

that a value obtained by subtracting a pressure

corresponding to the height difference between the liquid

level of the liquefied carbon dioxide L in the tank 21 and

the pipe top portion 25t from a value obtained by adding

the pressure loss AP that is generated by the pipe pressure resistance part 30A, 30B, or 30C to the tank operating pressure Pt exceeds the setting pressure lower limit value

Ps obtained by adding a safety margin value to the triple

point pressure value of the liquefied carbon dioxide L.

[00631

In this way, an appropriate pressure loss AP according

to the height of the pipe top portion 25t of the loading

pipe 25 is generated by the pipe pressure resistance part

A, 30B, or 30C to be able to increase the pressure Pc of

the liquefied carbon dioxide L. In this way, the pressure

Pc of the liquefied carbon dioxide L in the loading pipe 25

becomes equal to or higher than the setting pressure lower

limit value Ps that is set according to the triple point

pressure of the liquefied carbon dioxide L. In this way,

it is possible to suppress the generation of dry ice due to

solidification of the liquefied carbon dioxide L in the

loading pipe 25.

[0064]

(3) In the tank system 20A or 20C according to a third

aspect, in the tank system 20A or 20C of the above (2), the

pipe pressure resistance part 30A or 30C is provided at the

lower end 25b of the loading pipe 25.

[00651

In this way, due to the pipe pressure resistance part

A or 30C provided at the lower end 25b of the loading pipe

, the generation of dry ice due to the solidification of

the liquefied carbon dioxide L in the loading pipe 25 is

suppressed. Further, the pipe pressure resistance part 30A

or 30C can be additionally provided even with respect to

the lower end 25b of the loading pipe 25 of the existing

tank system.

[00661

(4) In the tank system 20B according to a fourth aspect,

in the tank system 20B of the above (2), the pipe pressure

resistance part 30B is higher than the lower end 25b of the

loading pipe 25, and the height H thereof from the tank

bottom surface 21b of the tank 21 is provided such that the

pressure of the liquefied carbon dioxide L that has passed

through the pipe pressure resistance part 30B does not fall

below the triple point pressure value.

[0067]

In this way, in a case where the pipe pressure

resistance part 30B is installed at a position higher than

the lower end 25b of the loading pipe 25 and lower than the

pipe top portion 25t, the pressure of the liquefied carbon

dioxide L becomes equal to or higher than the setting

pressure lower limit value Ps even on the lower side (the

lower end 25b side) with respect to the pipe pressure

resistance part 30B. In this way, it is possible to suppress

the generation of dry ice due to the occurrence of a pressure drop of the liquefied carbon dioxide L that has passed through the pipe pressure resistance part 30B on the lower side with respect to the pipe pressure resistance part 30B.

[00681

(5) In the tank system 20A, 20B, or 20C according to

a fifth aspect, in the tank system 20A, 20B, or 20C of any

one of the above (1) to (4), the pipe pressure resistance

part 30A, 30B, or 30C has the flow opening portion 30a which

has the opening area A2, A3, A4, or A5 smaller than the flow

path cross-sectional area Al in the loading pipe 25 and

through which the liquefied carbon dioxide L flows.

[00691

The pipe pressure resistance part 30A, 30B, or 30C has

a simple configuration having the flow opening portion 30a,

and can realize suppression of the generation of dry ice in

the liquefied carbon dioxide L at low cost.

[0070]

(6) In the tank system 20C according to a sixth aspect,

in the tank system 20C of the above (5), the pipe pressure

resistance part 30C includes the control valve 35 that makes

the opening area A5 of the flow opening portion 30a variable,

and the control device 60 that adjusts the opening degree

of the flow opening portion 30a in the control valve 35.

[0071]

In this way, the pressure loss AP that is generated by the pipe pressure resistance part 30C can be adjusted by adjusting the opening degree of the flow opening portion a in the control valve 35 by the control device 60.

Therefore, it becomes possible to appropriately adjust the

pressure loss AP that increases the pressure of the

liquefied carbon dioxide L according to the operating

condition or the like of the tank system 20C.

[00721

(7) In the tank system 20C according to a seventh

aspect, the tank system 20C of the above (6) further

includes the pipe top portion pressure sensor 52 that

detects the pressure Pc of the liquefied carbon dioxide L

in the pipe top portion 25t of the loading pipe 25, in which

the control device 60 adjusts the opening degree of the

control valve 35, based on the detection value in the pipe

top portion pressure sensor 52.

[0073]

In this way, the pressure loss AP that is generated by

the pipe pressure resistance part 30C can be adjusted

according to the pressure Pc of the liquefied carbon dioxide

L in the pipe top portion 25t detected by the pipe top

portion pressure sensor 52. Therefore, it becomes possible

to appropriately adjust the pressure loss AP that increases

the pressure of the liquefied carbon dioxide L such that

the pressure Pc of the liquefied carbon dioxide L in the pipe top portion 25t does not fall below the setting pressure lower limit value Ps.

[0074]

(8) The ship 1A. 1B, or 1C according to an eighth

aspect includes the hull 2, and the tank system 20A, 20B,

or 20C of any one of the above (1) to (7), which is provided

in the hull 2.

[0075]

In this way, it becomes possible to provide the ship

1A, 1B, or 1C provided with the tank system 20A, 20B, or

C in which in a case where the liquefied carbon dioxide L

is contained in the tank 21, the generation of dry ice in

the loading pipe 25 is suppressed and the operation of the

tank 21 can be performed smoothly.

Industrial Applicability

[0076]

According to the present disclosure, it is possible to

suppress the generation of dry ice in the loading pipe and

smoothly perform the operation of the tank.

Reference Signs List

[0077]

The reference in this specification to any prior

publication (or information derived from it), or to any

matter which is known, is not, and should not be taken as an

acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

[0078]

Throughout this specification and the claims which

follow, unless the context requires otherwise, the word

"comprise", and variations such as "comprises" and

"comprising", will be understood to imply the inclusion of

a stated integer or step or group of integers or steps but

not the exclusion of any other integer or step or group of

integers or steps.

[0079]

While various embodiments of the present invention

have been described above, it should be understood that they

have been presented by way of example only, and not by way

of limitation. It will be apparent to a person skilled in

the relevant art that various changes in form and detail

can be made therein without departing from the spirit and

scope of the invention. Thus, the present invention should

not be limited by any of the above described exemplary

embodiments.

[0080]

1A, 1B, 1C: ship

2: hull

2a: bow

2b: stern

3A, 3B: broadside

: upper deck

7: superstructure

8: tank system storage compartment

A, 20B, 20C: tank system

21: tank

21b: tank bottom surface

: loading pipe

b: lower end

f: inner peripheral surface

t: pipe top portion

A, 30B, 30C: pipe pressure resistance part

a: flow opening portion

31: orifice

31a: plate portion

31b: through-hole

32: perforated plate

32a: plate portion

32b: through-hole

33: flap

33a: outer peripheral edge

33b: gap

: control valve

a: valve body

35b: gap

51: tank internal pressure sensor

52: pipe top portion pressure sensor

60: control device

61: CPU

62: ROM

63: RAM

64: HDD

65: signal receiving module

71: signal receiving unit

72: opening degree control unit

73: command signal output unit

Al: flow path cross-sectional area

A2, A3, A4, A5: opening area

Da: bow-stern direction

Dp: pipe axis direction

Dv: up-down direction

H: height of pipe pressure resistance part from tank

bottom surface

Hi: liquid level height of liquefied carbon dioxide in

tank

H2: height of pipe top portion of loading pipe from

tank bottom surface

L: liquefied carbon dioxide

AP: pressure loss

Pc: pressure

Ps: setting pressure lower limit value

Pt: operating pressure

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

[Claim 1]

A tank system comprising:

a tank that contains liquefied carbon dioxide therein;

a loading pipe extending in a vertical direction,

having a lower end that is open into the tank, and through

which liquefied carbon dioxide that is supplied from an

outside of the tank is fed from the lower end into the tank;

and

a pipe pressure resistance part that is provided close

to the lower end with respect to a pipe top portion that is

located at a highest position in the loading pipe, and

generating a pressure loss in the liquefied carbon dioxide

flowing through the loading pipe,

wherein the pipe pressure resistance part generates a

pressure loss that is determined such that a value obtained

by subtracting a pressure corresponding to a height

difference between a liquid level of the liquefied carbon

dioxide in the tank and the pipe top portion from a value

obtained by adding the pressure loss that is generated by

the pipe pressure resistance part to a tank operating

pressure exceeds a setting pressure lower limit value

obtained by adding a safety margin value to a triple point

pressure value of the liquefied carbon dioxide.
[Claim 2]

The tank system according to claim 1, wherein the pipe

pressure resistance part is provided at the lower end of

the loading pipe.
[Claim 3]

The tank system according to claim 1, wherein the pipe

pressure resistance part is higher than the lower end of

the loading pipe, and a height thereof from a tank bottom

surface of the tank is provided such that a pressure of the

liquefied carbon dioxide that has passed through the pipe

pressure resistance part does not fall below the triple

point pressure value.
[Claim 4]

The tank system according to any one of claims 1 to 3,

wherein the pipe pressure resistance part has a flow opening

portion which has an opening area smaller than a flow path

cross-sectional area in the loading pipe and through which

the liquefied carbon dioxide flows.
[Claim 5]

The tank system according to claim 4, wherein the pipe

pressure resistance part includes a control valve that makes an opening area of the flow opening portion variable, and a control device that adjusts an opening degree of the flow opening portion in the control valve.
[Claim 6]

The tank system according to claim 5, further

comprising:

a pipe top portion pressure sensor that detects a

pressure of the liquefied carbon dioxide in the pipe top

portion of the loading pipe,

wherein the control device adjusts an opening degree

of the control valve, based on a detection value in the pipe

top portion pressure sensor.
[Claim 7]

A ship comprising:

a hull; and

the tank system according to any one of claims 1 to 6,

which is provided in the hull.