AU2020409191B2

AU2020409191B2 - Ship

Info

Publication number: AU2020409191B2
Application number: AU2020409191A
Authority: AU
Inventors: Toshinori Ishida; Shinsuke Morimoto; Toshio Ogata
Original assignee: Mitsubishi Shipbuilding Co Ltd
Current assignee: Mitsubishi Shipbuilding Co Ltd
Priority date: 2019-12-19
Filing date: 2020-09-08
Publication date: 2024-05-16
Anticipated expiration: 2040-09-08
Also published as: CN114787029A; DK4079622T3; CN114787029B; JP2021095066A; EP4079622A1; EP4079622A4; KR20220093241A; WO2021124622A1; JP7377094B2; EP4079622B1; KR102703867B1; AU2020409191A1

Abstract

A ship comprising: a ship body; a tank that is provided in the ship body and stores one of ammonia and carbon dioxide; a supply line through which the other of ammonia and carbon dioxide is supplied into the tank; a discharge line that discharges a gas mixture obtained by mixing one of ammonia and carbon dioxide stored in the tank with the other of ammonia and carbon dioxide supplied into the tank through the supply line when the other of ammonia and carbon dioxide is supplied into the tank through the supply line; and a water tank that is provided in the ship body, that stores water, and into which the gas mixture discharged from the discharge line is introduced.

Description

DESCRIPTION

Title of Invention

SHIP

Technical Field

[0001]

The present disclosure relates to a ship.

The present application claims priority with respect

to Japanese Patent Application No. 2019-228934 filed in

Japan on December 19, 2019, the content of which is

incorporated herein by reference.

Background Art

[0002]

A liquefied gas carrier or the like is provided with

a liquefied gas storage tank. Such a tank may be filled

with an inert gas and then the inert gas in the tank may be

replaced with air or the like such that the liquefied gas

remaining in the tank does not come into contact with oxygen

when the tank is opened for maintenance or the like (see,

for example, PTL 1).

Citation List

Patent Literature

[0003]

[PTL 1] Japanese Unexamined Patent Publication No.

2013-193653

Summary of Invention

Technical Problem

[0004]

By the way, the type of gas stored in the tank may be

switched in the liquefied gas storage tank. At this time,

a problem may arise due to contact between the residual gas

of a first gas stored in the tank before the switching and

a second gas stored in the tank after the switching.

Examples of the problem include solid generation resulting

from a chemical reaction between the first gas and the

second gas. In addition, the first gas may be mixed with

the second gas and the first gas may remain in the tank

after the switching. Accordingly, in a case where the type

of gas stored in the tank is switched, as in the case of

the inert gas of PTL 1, the second gas needs to be loaded

into the tank after the first gas in the tank is replaced

with the inert gas.

However, as for the method described above, it is

necessary to sequentially execute the steps of discharging

the first gas to the outside of the tank, performing

replacement with the inert gas or the like in the tank, and

loading the second gas into the tank in switching the type

of gas loaded into the tank. As a result, it takes time

and effort to switch the type of gas loaded into the tank.

In addition, depending on the type of the residual gas in

the tank, the residual gas cannot be directly released from

the tank into the atmosphere, and it may take time and

effort to treat the residual gas.

[00051

Preferred embodiments of the present invention seek to

provide a ship in which the type of gas loaded into a tank

can be switched with ease and speed.

Solution to Problem

[00061

According to one aspect of the present invention,

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

provided in the hull and storing either ammonia or carbon

dioxide; a supply line supplying the other of the ammonia

and the carbon dioxide into the tank; a discharge line

discharging, when the other of the ammonia and the carbon

dioxide is supplied into the tank through the supply line,

a mixed gas in which one of the ammonia and the carbon

dioxide stored in the tank and the other of the ammonia

and the carbon dioxide supplied into the tank by the

supply line are mixed; and a water tank provided in the

hull and storing water, the mixed gas discharged from the

discharge line being introduced into the water tank.

[0006A]

In accordance with another aspect of the present invention, there is provided a method for switching the type of gases loaded on a ship, which is provided with: a hull; a tank provided in the hull and storing either ammonia or carbon dioxide; a supply line through which the other of the ammonia and the carbon dioxide is supplied to the tank; a first discharge line through which mixed gas of the ammonia and the carbon dioxide is discharged from the tank; and a water tank provided in the hull and storing water, the method comprising: discharging mixed gas of ammonia and carbon dioxide from the tank through the first discharge line when the other of the ammonia and the carbon dioxide is supplied to the tank through the supply line; and introducing the mixed gas, which is discharged from the tank through the first discharge line, to the water tank.

Advantageous Effects of Invention

[0007]

According to the ship of the present disclosure, it is

possible to efficiently switch the type of gas loaded into

the tank and work can be facilitated and expedited.

Brief Description of Drawings

[0008]

Fig. 1 is a plan view illustrating a schematic

configuration of a ship according to an embodiment of the

present disclosure.

Fig. 2 is a side cross-sectional view illustrating a

state where liquefied carbon dioxide is loaded in a tank to

which the ship according to the embodiment of the present

disclosure is applied.

Fig. 3 is a side cross-sectional view illustrating a

state where liquefied ammonia is loaded in the tank to which

the ship according to the embodiment of the present

disclosure is applied.

Fig. 4 is a side cross-sectional view illustrating a

state where ammonia gas remains in the tank with the

liquefied ammonia discharged in the ship according to the

embodiment of the present disclosure.

Fig. 5 is a side cross-sectional view illustrating a

state where the liquefied carbon dioxide is supplied to the

tank and a mixed gas is sent into a water tank in the ship

according to the embodiment of the present disclosure.

Fig. 6 is a side cross-sectional view illustrating a

state where carbon dioxide gas remains in the tank with the

liquefied carbon dioxide discharged in the ship according

to the embodiment of the present disclosure.

Fig. 7 is a side cross-sectional view illustrating a

state where the liquefied ammonia is supplied to the tank

and the mixed gas is sent into the water tank in the ship

according to the embodiment of the present disclosure.

Description of Embodiments

[00091

Hereinafter, a ship according to an embodiment of the

present disclosure will be described with reference to Figs.

1 to 7.

(Configuration of Hull of Ship)

A ship 1 of the embodiment of the present disclosure

illustrated in Figs. 1 and 2 is capable of selectively

carrying, for example, liquefied carbon dioxide and

liquefied ammonia. The ship 1 includes at least a hull 2,

a tank 21, an upper supply line 32, a lower supply line 33

as a supply line, a discharge line 35, and a water tank 50.

[0010]

(Hull Configuration)

As illustrated in Fig. 1, the hull 2 has a pair of

broadsides 3A and 3B, a ship bottom (not illustrated), and

a deck 5, which form the outer shell of the hull 2. The

broadsides 3A and 3B are provided with a pair of broadside

skins respectively forming the left and right broadsides.

The ship bottom (not illustrated) is provided with a ship

bottom skin connecting the broadsides 3A and 3B. By the

pair of broadsides 3A and 3B and the ship bottom (not

illustrated), the outer shell of the hull 2 has a U shape

in a cross section orthogonal to a ship stern direction Da.

The deck 5 exemplified in this embodiment is a whole deck

exposed to the outside. In the hull 2, an upper structure

7 having a living quarter is formed on the deck 5 on a stern

2b side.

[0011]

In the hull 2, a cargo loading section (hold) 8 is

formed closer to a bow 2a side than the upper structure 7.

The cargo loading section 8 is recessed toward the ship

bottom (not illustrated) below the deck 5 and is open upward.

[0012]

(Tank Configuration)

A plurality of the tanks 21 are disposed in the cargo

loading section 8. In this embodiment, for example, a total

of seven tanks 21 are disposed in the cargo loading section

8. The tank 21 is not limited in any manner in terms of

layout and installation number in the cargo loading section

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

cylindrical shape extending in the horizontal direction

(specifically, ship stern direction). The tank 21 is not

limited to a cylindrical tank and may be spherical.

[0013]

(Supply Line Configuration)

As illustrated in Fig. 2, the upper supply line 32 and

the lower supply line 33 are provided in each tank 21.

The upper supply line 32 reaches the inside of the

tank 21 from the outside of the tank 21. An opening portion

32a opening to the upper portion in the tank 21 is formed at the tip of the upper supply line 32. Here, the upper portion in the tank means the region in the tank 21 that is on the side closer to the upper end of the tank 21 than the center of the tank 21 in the ship height direction (that is, the up-down direction of the tank 21). As an example, the portion can be the top of the tank 21. The upper supply line 32 is provided with an opening-closing valve 32v. In addition, the discharge line 35 is branch-connected to the upper supply line 32.

[0014]

The lower supply line 33 reaches the inside of the

tank 21 from the outside of the tank 21. An opening portion

33a opening to the lower portion in the tank 21 is formed

at the tip of the lower supply line 33. Here, the lower

portion in the tank 21 means the region in the tank 21 that

is on the side closer to the lower end of the tank 21 than

the center of the tank 21 in the ship height direction. As

an example, the portion can be the bottom portion of the

tank 21. The lower supply line 33 is provided with an

opening-closing valve 33v.

[0015]

(Discharge Line Configuration)

When the type of gas loaded into the tank 21 is

switched, the discharge line 35 discharges the gas stored

in the tank 21 and containing at least one of ammonia and carbon dioxide to the outside of the tank 21. One end side of the discharge line 35 branches from the upper supply line

32. The discharge line 35 is provided with an opening

closing valve 35v.

[0016]

(Water Tank Configuration)

The water tank 50 is provided in the hull 2 (see Fig.

1). The water tank 50 may be, for example, a ballast tank

provided in the hull 2. Water W can be stored in the water

tank 50. The water W stored in the water tank 50 may be

seawater. The other end of the discharge line 35 is disposed

in the water tank 50. As a result, the gas discharged from

the tank 21 through the discharge line 35 is introduced into

the water W in the water tank 50.

[0017]

The water tank 50 exemplified in this embodiment is

provided with a heating unit 52. The heating unit 52 is

configured to be capable of heating the water W in the water

tank 50. For example, the component (carbon dioxide or

ammonia) contained in the gas discharged from the tank may

cause a chemical reaction via the water W and a substance

resulting from the chemical reaction (for example, ammonium

carbonate) may be dissolved in the water W in the water tank

50. In this case, it is possible to perform separation into

the components before the chemical reaction (carbon dioxide, ammonia, and water) by the heating unit 52 heating the water

W in the water tank 50.

[0018]

Further, a separated gas discharge line 53 is

connected to the water tank 50 exemplified in this

embodiment. By the separated gas discharge line 53, the

gas containing the above components separated by the heating

unit 52 can be discharged to the outside of the ship.

[0019]

(Liquefied Gas Loading into and Discharge from Tank)

Either liquefied carbon dioxide Lc or liquefied

ammonia La is selectively loaded into the tank 21.

In a case where the ship 1 repeatedly carries only one

of the liquefied carbon dioxide Lc and the liquefied ammonia

La, liquefied carbon dioxide loading into the tank 21 or

liquefied ammonia loading into the tank 21 is performed as

follows.

[0020]

(Liquefied Carbon Dioxide Loading into Tank)

As illustrated in Fig. 2, in order to load the

liquefied carbon dioxide Lc into the tank 21, a pipe (not

illustrated) for supplying the liquefied carbon dioxide Lc

from an outboard liquefied carbon dioxide supply facility

or the like is connected to the lower supply line 33. The

opening-closing valve 33v is opened, and the liquefied carbon dioxide Lc is sent from the outside of the ship into the lower supply line 33. Then, the liquefied carbon dioxide Lc is loaded into the tank 21 from the opening portion 33a. In this manner, the liquefied carbon dioxide

Lc is stored in the tank 21. In addition, carbon dioxide

gas Gc resulting from partial vaporization of the liquefied

carbon dioxide Lc is in the upper portion in the tank 21.

The liquefied carbon dioxide Lc may be loaded into the tank

21 through the upper supply line 32 with the opening-closing

valve 32v open.

[0021]

(Liquefied Ammonia Loading into Tank)

As illustrated in Fig. 3, in order to load the

liquefied ammonia La into the tank 21, a pipe (not

illustrated) for supplying the liquefied ammonia La from an

outboard liquefied ammonia supply facility or the like is

connected to the lower supply line 33. The opening-closing

valve 33v is opened, and the liquefied ammonia La is sent

from the outside of the ship into the lower supply line 33.

Then, the liquefied ammonia La is loaded into the tank 21

from the opening portion 33a. In this manner, the liquefied

ammonia La is stored in the tank 21. In addition, ammonia

gas Ga resulting from partial vaporization of the liquefied

ammonia La is in the upper portion in the tank 21. The

liquefied ammonia La may be loaded into the tank 21 through the upper supply line 32 with the opening-closing valve 32v open.

[0022]

(Gas Replacement from Liquefied Ammonia to Liquefied

Carbon Dioxide)

In the case of liquefied ammonia-to-liquefied carbon

dioxide replacement of the liquefied gas loaded into the

tank 21, first, the liquefied ammonia La in the tank 21 is

discharged to an outboard liquefied ammonia recovery

facility or the like. In order to discharge the liquefied

ammonia La stored in the tank 21, the opening-closing valve

33v is opened and the liquefied ammonia La is suctioned out

of the tank 21 through the lower supply line 33 by, for

example, a cargo pump (not illustrated). As a result, the

liquefied ammonia La in the tank 21 is discharged to the

outboard liquefied ammonia recovery facility or the like

through the lower supply line 33.

After the liquefied ammonia La in the tank 21 is

discharged, the ammonia gas Ga remains in the tank 21 as

illustrated in Fig. 4.

[0023]

Subsequently, as illustrated in Fig. 5, the liquefied

carbon dioxide Lc is supplied to the lower portion of the

tank 21. In order to supply the liquefied carbon dioxide

Lc to the tank 21, the opening-closing valve 33v is opened and the liquefied carbon dioxide Lc is sent into the lower supply line 33 from the outside of the ship. The liquefied carbon dioxide Lc is loaded into the tank 21 from the opening portion 33a. The liquefied carbon dioxide Lc is higher in specific gravity than the ammonia gas Ga in the tank 21.

Accordingly, the liquefied carbon dioxide Lc sent into the

tank 21 is stored in the lower portion of the tank 21. The

ammonia gas Ga is stored above the liquefied ammonia La in

the tank 21. In addition, the carbon dioxide gas Gc

generated by the liquefied carbon dioxide Lc vaporizing also

accumulates in the upper portion of the tank 21. In other

words, when the liquefied carbon dioxide Lc is supplied into

the tank 21, mixed gas Gm of the ammonia gas Ga and the

carbon dioxide gas Gc is stored in the upper portion of the

tank 21.

[00241

When the liquefied carbon dioxide Lc is sent into the

tank 21 as described above, the opening-closing valve 35v

provided on the discharge line 35 is opened. When the

liquefied carbon dioxide Lc continues to be supplied to the

lower portion of the tank 21, the mixed gas Gm of the ammonia

gas Ga and the carbon dioxide gas Gc in the upper portion

of the tank 21 is pushed upward in the tank 21 as the amount

of the liquefied carbon dioxide Lc in the tank 21 increases.

After the push, the mixed gas Gm flows into the upper supply line 32 from the opening portion 32a open in the upper portion in the tank 21. After flowing into the upper supply line 32, the mixed gas Gm is introduced into the water W in the water tank 50 through the discharge line 35.

[0025]

Then, ammonia (NH3 ) and carbon dioxide (C02), which are

components contained in the mixed gas Gm, are released into

the water W and cause a chemical reaction via the water W

(H 2 0) . Then, solid ammonium carbonate ( (NH 4 )2CO 3 ) or

ammonium bicarbonate (NH 4 HCO 3 ) is generated as a result of

the chemical reaction. The generated ammonium carbonate or

ammonium bicarbonate is stored in the water tank 50 in a

state of being dissolved in the water W.

[0026]

If not the mixed gas Gm but only the ammonia gas Ga is

discharged from the upper portion of the tank 21 to the

upper supply line 32 in the initial stage in which the

liquefied carbon dioxide Lc is sent into the tank 21, the

ammonia gas Ga may be recovered, without being sent into

the water tank 50, through the upper supply line 32 by an

ammonia gas recovery facility or the like provided outside

the ship.

[0027]

The opening-closing valves 33v and 35v are closed when

a predetermined amount of the liquefied carbon dioxide Lc is stored in the tank 21. As a result, the work of replacing the liquefied gas loaded into the tank 21 from the liquefied ammonia La to the liquefied carbon dioxide Lc is completed.

[00281

(Gas Replacement from Liquefied Carbon Dioxide to

Liquefied Ammonia)

In the case of liquefied carbon dioxide-to-liquefied

ammonia replacement of the liquefied gas loaded into the

tank 21, first, the liquefied carbon dioxide Lc in the tank

21 is discharged to an outboard liquefied carbon dioxide

recovery facility or the like. In order to discharge the

liquefied carbon dioxide Lc stored in the tank 21, the

opening-closing valve 33v is opened and the liquefied carbon

dioxide Lc is suctioned out of the tank 21 through the lower

supply line 33 by, for example, a cargo pump (not

illustrated). As a result, the liquefied carbon dioxide Lc

in the tank 21 is discharged to the outboard liquefied

carbon dioxide recovery facility or the like through the

lower supply line 33.

After the liquefied carbon dioxide Lc in the tank 21

is discharged, the carbon dioxide gas Gc remains in the tank

21 as illustrated in Fig. 6.

[0029]

Subsequently, as illustrated in Fig. 7, the liquefied

ammonia La is supplied to the lower portion of the tank 21.

In order to supply the liquefied ammonia La to the tank 21,

the opening-closing valve 33v is opened and the liquefied

ammonia La is sent into the lower supply line 33 from the

outside of the ship. Then, the liquefied ammonia La is

loaded into the tank 21 from the opening portion 33a.

[00301

The liquefied ammonia La is higher in specific gravity

than the carbon dioxide gas Gc in the tank 21. Accordingly,

the liquefied ammonia La sent into the tank 21 is stored in

the lower portion of the tank 21. The carbon dioxide gas

Gc is stored above the liquefied carbon dioxide Lc in the

tank 21. In addition, the ammonia gas Ga generated by the

liquefied ammonia La vaporizing also accumulates in the

upper portion of the tank 21. In other words, when the

liquefied ammonia La is supplied into the tank 21, the mixed

gas Gm of the carbon dioxide gas Gc and the ammonia gas Ga

is stored in the upper portion of the tank 21.

[0031]

When the liquefied ammonia La is sent into the tank 21

as described above, the opening-closing valve 35v provided

on the discharge line 35 is opened. When the liquefied

ammonia La continues to be supplied to the lower portion of

the tank 21, the mixed gas Gm of the carbon dioxide gas Gc

and the ammonia gas Ga in the upper portion of the tank 21

is pushed upward in the tank 21 as the amount of the liquefied ammonia La in the tank 21 increases. After the push, the mixed gas Gm flows into the upper supply line 32 from the opening portion 32a open in the upper portion in the tank 21. After flowing into the upper supply line 32, the mixed gas Gm is introduced into the water W in the water tank 50 through the discharge line 35.

[00321

Then, ammonia (NH3 ) and carbon dioxide (C02), which are

components contained in the mixed gas Gm, are released into

the water W and cause a chemical reaction via the water W

(H 2 0) . Then, solid ammonium carbonate ( (NH 4 )2CO 3 ) or

ammonium bicarbonate (NH 4 HCO 3 ) is generated as a result of

the chemical reaction. The generated ammonium carbonate or

ammonium bicarbonate is stored in the water tank 50 in a

state of being dissolved in the water W.

[00331

If not the mixed gas Gm but only the carbon dioxide

gas Gc is discharged from the upper portion of the tank 21

to the upper supply line 32 in the initial stage in which

the liquefied ammonia La is sent into the tank 21, the

carbon dioxide gas Gc may be recovered as it is by, for

example, a carbon dioxide recovery facility provided outside

the ship or may be released to the outside of the ship

without being sent into the water tank 50.

[00341

The opening-closing valves 33v and 35v are closed when

a predetermined amount of the liquefied carbon dioxide Lc

is stored in the tank 21. As a result, the liquefied gas

loaded into the tank 21 can be replaced from the liquefied

carbon dioxide Lc to the liquefied ammonia La.

[00351

(Pyrolysis Treatment of Water in Water Tank)

As described above, the water W in the water tank 50

can be pyrolyzed by operating the heating unit 52. The

ammonium carbonate- or ammonium bicarbonate-dissolved water

W is heated when the heating unit 52 is operated. When the

water W in the water tank 50 is heated to, for example, 580C

or higher, the ammonium carbonate or ammonium bicarbonate

is pyrolyzed into ammonia, carbon dioxide, and the water W.

These pyrolyzed ammonia and carbon dioxide are discharged

to, for example, a treatment facility provided outside the

ship through the separated gas discharge line 53 or the like.

[00361

(Action and Effect)

The ship 1 of the above embodiment includes the tank

21 where one of the ammonia gas Ga and the carbon dioxide

gas Gc remains (is stored), the lower supply line 33

supplying the other of the liquefied ammonia La and the

liquefied carbon dioxide Lc into the tank 21, the discharge

line 35 discharging the mixed gas of the ammonia gas Ga or the carbon dioxide gas Gc that remains in the tank 21 and the gas vaporized from the other of the liquefied ammonia

La and the liquefied carbon dioxide Lc when the other of

the liquefied ammonia La and the liquefied carbon dioxide

Lc is supplied from the lower supply line 33, and the water

tank 50 into which the mixed gas discharged from the

discharge line 35 is introduced.

[00371

In such a configuration, when the other of the

liquefied ammonia La and the liquefied carbon dioxide Lc is

supplied through the lower supply line 33 into the tank 21

where one of the ammonia gas Ga and the carbon dioxide gas

Gc remains, the mixed gas in which ammonia and carbon

dioxide are mixed is discharged from the tank 21. This

mixed gas is introduced into the water tank 50 through the

discharge line 35 and released into the water W. Then, a

chemical reaction occurs as a result of ammonia-carbon

dioxide-water contact in the tank 21, and ammonium carbonate

or ammonium bicarbonate is generated. The ammonium

carbonate or ammonium bicarbonate is dissolved in the water

W and stored. Accordingly, there is no need to discharge

the gas or product discharged from the tank 21 in the event

of gas type switch to the outside of the ship. In other

words, gas type switch can be performed even in a case where

it is difficult to release the gas discharged from the tank

21 into the atmosphere. As a result, it is possible to

efficiently switch the type of gas loaded into the tank 21

and gas type switch can be facilitated and expedited.

[00381

The ship 1 of the above embodiment further includes

the heating unit 52 heating the water W in the water tank

and the separated gas discharge line 53 discharging the

gas separated from the water W by the heating unit 52 heating

the water W.

In such a configuration, in the event of gas type

switch, the water W in the water tank 50 in which the product

of a mixed gas-water chemical reaction is dissolved can be

heated by the heating unit 52. Accordingly, the ammonium

carbonate or ammonium bicarbonate dissolved in the water W

can be pyrolyzed to separate the gas such as carbon dioxide

gas and ammonia gas from the water W. The gas separated

from the water W in the water tank 50 can be discharged from

the separated gas discharge line 53. Accordingly, the gas

separated from the water W can be treated at an appropriate

timing regardless of, for example, the situation of gas type

switch.

[00391

(Other Embodiments)

Although an embodiment of the present disclosure has

been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment and also includes, for example, design changes within the gist of the present disclosure.

Although the water tank 50 is provided with the heating

unit 52 in the above embodiment, the heating unit 52 may be

provided in an outboard treatment facility or the like. In

that case, the water W in the water tank 50 is discharged

to the outside of the ship with the component and product

contained in the gas discharged from the discharge line 35

dissolved and is treated at the outboard treatment facility

or the like.

Exemplified in the above embodiment is a case where

the discharge line 35 is branch-connected to the upper

supply line 32. Alternatively, the discharge line 35 may

be directly connected to the tank 21 with the upper supply

line 32 omitted.

Described in the above embodiment is a case where the

liquefied ammonia La or the liquefied carbon dioxide Lc is

supplied into the tank 21 from the lower portion of the tank

21 by the lower supply line 33. Alternatively, the

liquefied ammonia La or the liquefied carbon dioxide Lc may

be supplied into the tank 21 from, for example, the upper

portion or center of the tank 21 instead of the lower portion.

[0040]

The ship 1 described in the embodiment is, for example,

grasped as follows.

[00411

(1) A ship 1 according to a first aspect includes: a

hull 2; a tank 21 provided in the hull 2 and storing either

ammonia or carbon dioxide; a supply line 33 supplying the

other of the ammonia and the carbon dioxide into the tank

21; a discharge line 35 discharging, when the other of the

ammonia and the carbon dioxide is supplied into the tank 21

through the supply line 33, a mixed gas in which one of the

ammonia and the carbon dioxide stored in the tank 21 and

the other of the ammonia and the carbon dioxide supplied

into the tank 21 by the supply line 33 are mixed; and a

water tank 50 provided in the hull 2 and storing water W,

the mixed gas discharged from the discharge line 35 being

introduced into the water tank 50.

[0042]

As for the ship 1, in a case where the type of gas

loaded into the tank 21 is switched, the other of ammonia

and carbon dioxide is supplied through the supply line 33

into the tank 21 in which one of ammonia and carbon dioxide

is stored. Then, the mixed gas of ammonia and carbon dioxide

is discharged from the discharge line 35. The mixed gas

discharged from the tank 21 is sent into the water tank 50

through the discharge line 35. As a result of contact between the mixed gas sent into the tank 21 and the water

W, ammonium carbonate or ammonium bicarbonate as an example

is generated as a product. This product dissolves in the

water W by being introduced into the water tank 50.

In this manner, when the type of gas loaded into the

tank 21 is switched, the mixed gas discharged from the tank

21 is allowed to chemically react with the water W and can

be stored in the water tank 50. Accordingly, there is no

need to discharge the gas or product discharged from the

tank 21 in the event of gas type switch to the outside of

the ship. In other words, gas type switch can be performed

even in a case where it is difficult to release the gas

discharged from the tank 21 into the atmosphere. As a

result, it is possible to efficiently switch the type of

gas loaded into the tank 21 and gas type switch can be

facilitated and expedited.

[0043]

(2) The ship 1 according to a second aspect, which is

the ship 1 of (1), further includes a heating unit 52 heating

the water W in the water tank 50; and a separated gas

discharge line 53 discharging a gas separated from the water

W by the heating unit 52 heating the water W.

[0044]

As a result, the water W in the water tank 50 in which

the product is dissolved can be heated. Accordingly, the ammonium carbonate or ammonium bicarbonate dissolved in the water W can be pyrolyzed to separate the gas such as carbon dioxide gas and ammonia gas from the water W. In addition, the gas separated from the water W in the water tank 50 can be discharged from the separated gas discharge line 53.

Accordingly, the gas separated from the water W can be

treated at an appropriate timing regardless of, for example,

the situation of switching the type of gas in the tank 21.

Industrial Applicability

[0045]

According to the ship of the present disclosure, it is

possible to efficiently switch the type of gas loaded into

the tank and work can be facilitated and expedited.

Reference Signs List

[0046]

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.

[0047]

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.

[0048]

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.

[0049]

1: ship

2: hull

2a: bow

2b: stern

3A, 3B: side

5: deck

7: upper structure

8: cargo loading section

21: tank

32: upper supply line

32a: opening portion

32v: opening-closing valve

33: supply line

33: lower supply line (supply line)

33a: opening portion

33v: opening-closing valve

35: discharge line

35v: opening-closing valve

50: water tank

52: heating unit

53: separated gas discharge line

Da: ship stern direction

Ga: ammonia gas

Gc: carbon dioxide gas

Gm: mixed gas

La: liquefied ammonia

Lc: liquefied carbon dioxide

W: water

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

[Claim 1]

A ship comprising:

a hull;

a tank provided in the hull and storing either ammonia

or carbon dioxide;

a supply line supplying the other of the ammonia and

the carbon dioxide into the tank;

a discharge line discharging, when the other of the

ammonia and the carbon dioxide is supplied into the tank

through the supply line, a mixed gas in which one of the

ammonia and the carbon dioxide stored in the tank and the

other of the ammonia and the carbon dioxide supplied into

the tank by the supply line are mixed; and

a water tank provided in the hull and storing water,

the mixed gas discharged from the discharge line being

introduced into the water tank.
[Claim 2]

The ship according to Claim 1, further comprising:

a heating unit heating the water in the water tank;

and

a separated gas discharge line discharging a gas

separated from the water by the heating unit heating the water.
[Claim 3]

A method for switching the type of gases loaded on a

ship, which is provided with:

a hull;

a tank provided in the hull and storing either ammonia

or carbon dioxide;

a supply line through which the other of the ammonia

and the carbon dioxide is supplied to the tank;

a first discharge line through which mixed gas of the

ammonia and the carbon dioxide is discharged from the tank;

and

a water tank provided in the hull and storing water,

the method comprising:

discharging mixed gas of ammonia and carbon dioxide

from the tank through the first discharge line when the

other of the ammonia and the carbon dioxide is supplied to

the tank through the supply line; and

introducing the mixed gas, which is discharged from

the tank through the first discharge line, to the water tank.
[Claim 4]

The method according to Claim 3, wherein the ship is

further provided with: a heating unit heating the water in the water tank; and a second discharge line through which gas is discharged from the water tank, wherein the method further comprising: heating the water in the water tank by the heating unit; and discharging gas, which has been separated from the water heated by the heating unit, is discharged from the water tank through the second discharge line.

2a

2 8

FIG. Da

21 21

3A 5

3B

2b