KR20230132669A - Vessel propelled to ammonia - Google Patents

Abstract

An ammonia-propelled vessel is provided by one embodiment of the present invention.
An ammonia-propelled ship according to an embodiment of the present invention includes a hull, a first fuel tank installed on the hull and storing liquid ammonia therein, a second fuel tank installed on the hull and storing liquid fuel therein, A combustion engine that receives liquid ammonia from a first fuel tank and ammonia vaporized by the liquid ammonia and receives liquid fuel from a second fuel tank to generate power, and carbon dioxide that removes carbon dioxide contained in the exhaust gas generated from the combustion engine. It may include a collection device.

Description

Vessel propelled to ammonia}

The present invention relates to an ammonia-propelled ship, and more specifically, to an ammonia-propelled ship that uses liquid ammonia as fuel and a carbon dioxide absorbent to reduce the carbon dioxide contained in the exhaust gas and reduce the cost of purchasing the absorbent. will be.

Generally, various engines installed on ships generate power by burning fuel, and exhaust gases generated during the combustion process of fuel contain nitrogen oxides, sulfur oxides, carbon dioxide, etc. As air pollution increases, regulations on various harmful substances contained in exhaust gas are becoming stricter. Not only nitrogen oxides and sulfur oxides, but also carbon dioxide are subject to emission regulations from the International Maritime Organization (IMO), a UN affiliate. I'm receiving it. In fact, the International Maritime Organization is seeking to reduce carbon dioxide emissions by 40% by 2030 and 70% by 2050 compared to 2008. Accordingly, there is a demand for the development of eco-friendly ships that generate power using low-carbon or decarbonized fuels, and liquid ammonia, which does not emit carbon dioxide when burned, is emerging as one of the next-generation eco-friendly fuels.

Liquid ammonia can be co-combusted with diesel or gasoline and used as fuel for the main engine or power generation engine, and the exhaust gas generated during combustion due to diesel or gasoline inevitably contains carbon dioxide. As a method of capturing carbon dioxide contained in exhaust gas, ships usually use a wet capture method that sprays an absorbent that absorbs carbon dioxide into the exhaust gas. In the past, amine compounds used as absorbents were supplied from external companies, so there was a problem of wasting a lot of money because both purchase fees and royalties had to be paid.

Accordingly, there is a need for a ship with a structure that uses liquid ammonia as fuel and a carbon dioxide absorbent to reduce carbon dioxide contained in exhaust gases while also reducing the cost of purchasing absorbents.

Republic of Korea Patent No. 10-2232540 (2021.03.22.)

The technical problem to be achieved by the present invention is to provide an ammonia-propelled ship that uses liquid ammonia as fuel and a carbon dioxide absorbent to reduce carbon dioxide contained in exhaust gas and reduce the cost of purchasing the absorbent.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

An ammonia-propelled ship according to an embodiment of the present invention for achieving the above technical problem includes a hull, a first fuel tank installed on the hull and storing liquid ammonia therein, installed on the hull, and a liquid ammonia inside. A second fuel tank that stores fuel, a combustion engine that receives the liquid ammonia or ammonia vaporized by the liquid ammonia from the first fuel tank and generates power by receiving the liquid fuel from the second fuel tank, and It includes a carbon dioxide capture device that removes carbon dioxide contained in exhaust gas generated from the combustion engine.

The carbon dioxide capture device can be supplied with the liquid ammonia or an ammonia aqueous solution mixed with the ammonia and fresh water.

The ammonia propulsion vessel is installed between the first fuel tank and the carbon dioxide capture device, and may further include an agitator for mixing the liquid ammonia or the ammonia and the fresh water.

The carbon dioxide capture device includes an absorption unit that injects the ammonia aqueous solution into the exhaust gas supplied from the combustion engine, and a regeneration unit that receives the ammonia aqueous solution in which carbon dioxide has been absorbed from the absorption unit and separates carbon dioxide from the ammonia aqueous solution. It can be included.

The carbon dioxide collection device includes a circulation pipe that circulates the ammonia aqueous solution from which carbon dioxide is separated in the regeneration section to the absorption section, and is installed on the circulation pipe to separate sediment contained in the ammonia aqueous solution using the difference in specific gravity. It may further include a separation unit.

According to the present invention, liquid ammonia and liquid fuel are mixed and used as fuel for a combustion engine, so the amount of carbon dioxide contained in the exhaust gas can be reduced compared to the conventional case of using only liquid fuel. In particular, it is possible to create an eco-friendly ship by reducing carbon dioxide emissions without using hydrogen, which is difficult to store and process, as a fuel.

In addition, because liquid ammonia is used as a carbon dioxide absorbent, the cost of purchasing the absorbent can be reduced, and carbon dioxide contained in exhaust gas can be removed, making it possible to easily satisfy the International Maritime Organization's emission regulations.

1 is a diagram schematically showing an ammonia-propelled ship according to an embodiment of the present invention.
Figure 2 is an enlarged view of the carbon dioxide capture device of Figure 1.
Figures 3 to 5 are operational diagrams for explaining the operation of an ammonia-propelled ship.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely provided to ensure that the disclosure of the present invention is complete and to be understood by those skilled in the art. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, with reference to FIGS. 1 to 5, an ammonia-propelled ship according to an embodiment of the present invention will be described in detail.

Since the ammonia-propelled ship according to an embodiment of the present invention uses a mixture of liquid ammonia and liquid fuel as fuel for a combustion engine, the amount of carbon dioxide contained in the exhaust gas can be reduced compared to the conventional case of using only liquid fuel. In particular, it is possible to create an eco-friendly ship by reducing carbon dioxide emissions without using hydrogen, which is difficult to store and process, as a fuel. In addition, since liquid ammonia is used as a carbon dioxide absorbent, the cost of purchasing absorbents can be reduced, and carbon dioxide contained in exhaust gas can also be removed, making it easy to satisfy the International Maritime Organization's emission regulations. there is.

Hereinafter, with reference to FIGS. 1 and 2, the ammonia-propelled ship 1 will be described in detail.

Figure 1 is a schematic diagram of an ammonia-propelled ship according to an embodiment of the present invention, and Figure 2 is an enlarged diagram of the carbon dioxide capture device of Figure 1.

The ammonia-propelled ship (1) according to the present invention includes a hull (10), a first fuel tank (20), a second fuel tank (30), a combustion engine (40), and a carbon dioxide capture device (50). do.

The hull 10 forms the main body of the ammonia-propelled ship 1, and has a streamlined outer shape to minimize resistance due to ocean currents. A first fuel tank 20, a second fuel tank 30, a combustion engine 40, and a carbon dioxide capture device 50 are installed in the hull 10.

The first fuel tank 20 is a tank that stores liquid ammonia therein, and at least one first fuel tank 20 may be installed in the hull 10. The first fuel tank 20 may be insulated on the inside to be suitable for storage of liquid ammonia at a low temperature of -33°C, and a first fuel supply pipe 21 is connected to one side to store the stored liquid ammonia in a combustion engine to be described later. It can be supplied as (40). At least part of the liquid ammonia flowing through the first fuel supply pipe 21 may be vaporized and supplied to the combustion engine 40 in a mixed state of liquid and gaseous phase, or may be supplied to the combustion engine 40 in a gaseous state. there is.

The second fuel tank 30 is a tank that stores liquid fuel, diesel or gasoline, and at least one second fuel tank 30 may be installed in the hull 10. The second fuel tank 30 is connected to a second fuel supply pipe 31 on one side and can supply the stored liquid fuel to the combustion engine 40.

The combustion engine 40 is supplied with liquid ammonia or ammonia in which liquid ammonia has been vaporized from the first fuel tank 20 and receives liquid fuel from the second fuel tank 30 to generate power, and is the main unit that generates propulsion. It may include an engine 41 and a power generation engine 42 that generates power. The main engine 41 and the power generation engine 42 may be liquid ammonia or an ammonia engine that co-fires ammonia and liquid fuel, respectively. In this case, the mixing ratio of ammonia and liquid fuel may be 70:30. Since the combustion engine 40 generates power by burning liquid ammonia or ammonia and liquid fuel together, the amount of carbon dioxide contained in the exhaust gas can be reduced compared to the conventional case of using only liquid fuel. In fact, as described above, when the mixing ratio of ammonia and liquid fuel is 70:30, the amount of carbon dioxide contained in the exhaust gas can be reduced by about 70% compared to when only liquid fuel is used. In addition, it has the advantage of enabling the creation of eco-friendly ships by reducing carbon dioxide emissions without using hydrogen, which is difficult to store and process, as fuel. In the drawing, it is shown that liquid ammonia or ammonia and liquid fuel are supplied to the main engine 41 or the power generation engine 42 through one pipe, but this is not limited to this, and the supply structure of liquid ammonia or ammonia and liquid fuel is not limited thereto. can be modified in various ways. The exhaust gas generated by combustion of fuel in the main engine 41 and the power generation engine 42 is discharged through the first exhaust pipe 41a and the second exhaust pipe 42a, respectively. 2 The exhaust pipe 42a is connected to the carbon dioxide capture device 50.

The carbon dioxide capture device 50 removes carbon dioxide contained in the exhaust gas by injecting liquid ammonia into the exhaust gas generated from the combustion engine 40, and uses at least one of the first exhaust pipe 41a and the second exhaust pipe 42a. Exhaust gas can be supplied from the fuel supply pipe 21, and liquid ammonia or liquid ammonia vaporized ammonia can be supplied through the fuel branch pipe 22 branched from the first fuel supply pipe 21. More specifically, the carbon dioxide capture device 50 can inject liquid ammonia or a 26 mass% aqueous ammonia solution mixed with ammonia and water into the exhaust gas. Ammonia aqueous solution has the property of absorbing carbon dioxide, so it can replace amine compounds that were conventionally used as absorbents. As a result, not only can the cost of purchasing absorbents be reduced, but it is also included in exhaust gas. Carbon dioxide can also be removed, making it easy to meet the International Maritime Organization's emission regulations. Liquid ammonia or aqueous ammonia solution can absorb carbon dioxide according to the reaction equation below.

<Reaction formula>

(1) NH ₃ + H ₂ O ↔ NH ₄ ⁺ + OH ^-

(2) CO ₂ + H ₂ O ↔ HCO ₃ ^- + H ⁺

(3) HCO ₃ ^- ↔ CO ₃ ^2- + H ⁺

(4) NH ₃ + HCO ₃ ^- ↔ NH ₂ COO ^- + H ₂ O

(5) H ₂ O ↔ H ⁺ + OH ^-

The above-mentioned fuel branch pipe 22 is branched from the first fuel supply pipe 21 and connects the first fuel tank 20 and the carbon dioxide collection device 50, and a control valve is installed at the branch point of the fuel branch pipe 22. (not shown) is installed so that the flow of liquid ammonia or ammonia on the first fuel supply pipe 21 side and the flow of liquid ammonia or ammonia on the fuel branch pipe 22 can be controlled simultaneously. A fresh water supply pipe 70 and an agitator 60 may be installed on this fuel branch pipe 22. The fresh water supply pipe 70 supplies fresh water from a fresh water generator (not shown) or a fresh water storage tank (not shown), and a control valve (not shown) is installed at the connection point of the fresh water supply pipe 70 to control fuel The flow of liquid ammonia or ammonia on the engine 22 side and the flow of fresh water on the fresh water supply pipe 70 can be controlled simultaneously. The stirrer 60 receives liquid ammonia or ammonia and water from the fuel branch pipe 22 and the fresh water supply pipe 70, respectively, to generate an ammonia aqueous solution. For example, it may be formed as an inline mixer.

The carbon dioxide capture device 50 includes an absorption unit 51 and a regeneration unit 52.

The absorber 51 receives exhaust gas from at least one of the first exhaust pipe 41a or the second exhaust pipe 42a connected to the combustion engine 40, and atomizes the ammonia aqueous solution supplied from the stirrer 60. ) or spray into fine particles. The absorption unit 51 may be formed as a gas contact type absorption tower to easily cope with the rocking of the ship, but is not limited to this and various methods may be applied. The exhaust gas is supplied to the lower part of the absorption part 51 and comes into contact with the ammonia solution sprayed from the upper part of the absorption part 51. As a result, carbon dioxide contained in the exhaust gas is absorbed into the ammonia solution and can be removed from the exhaust gas. The exhaust gas from which carbon dioxide has been removed is discharged to the outside through the exhaust pipe (40a) connected to the upper part of the absorber 51. Since an exothermic reaction occurs when carbon dioxide is absorbed into the absorbent, a separate cooling process is performed at the upper part of the absorber 51. It can be discharged after passing through. For example, the exhaust gas may be cooled in gas-liquid contact with a cooling medium such as fresh water sprayed from the upper part of the absorption unit 51 and then discharged through the exhaust pipe 40a, and the cooling medium in contact with the exhaust gas is collected and collected in the absorption unit 51. (51) After being discharged to the outside, it can be circulated back to the absorption unit 51 through a pressurization and cooling process. The ammonia solution absorbing carbon dioxide in the absorption unit 51 is supplied to the regeneration unit 52 along the supply line 51a.

The supply line (51a) has one end connected to the lower part of the absorption part 51 and the other end connected to the upper part of the regeneration part 52, so that the ammonia aqueous solution that absorbs the carbon dioxide discharged from the absorption part 51 is supplied to the upper part of the regeneration part 52. can be supplied. A pump 51b that pressurizes the ammonia solution absorbing carbon dioxide and a heat exchanger 51c that exchanges heat between the supply line 51a and the first circulation pipe 53a, which will be described later, may be installed on the supply line 51a. The heat exchange unit 51c exchanges heat with the ammonia aqueous solution that absorbs carbon dioxide at about 40 to 50°C discharged from the absorption unit 51 and the ammonia aqueous solution from which the carbon dioxide at about 80 to 150°C discharged from the regeneration unit 52 is separated. and heat it. That is, the heat exchange unit 51c is supplied with the ammonia aqueous solution supplied from the absorption unit 51 to the regeneration unit 52 through the supply line 51a, and the ammonia solution supplied from the regeneration unit 52 to the absorption unit 52 through the first circulation pipe 53a. By heat exchanging the ammonia aqueous solution circulating to (51), the temperature of the ammonia aqueous solution supplied to the regeneration unit (52) is increased and the temperature of the ammonia aqueous solution circulated to the absorption unit (51) is lowered. Therefore, carbon dioxide can be easily absorbed into the ammonia aqueous solution in the absorption unit 51, and carbon dioxide can be easily separated from the ammonia aqueous solution in the regeneration unit 52. The ammonia aqueous solution that absorbs the carbon dioxide heated in the heat exchange unit 51c may flow into the upper part of the regeneration unit 52.

The regeneration unit 52 receives an ammonia aqueous solution in which carbon dioxide has been absorbed from the absorption unit 51 and separates carbon dioxide from the ammonia aqueous solution. More specifically, the ammonia aqueous solution that absorbs carbon dioxide supplied to the upper part of the regeneration part 52 after being heated in the heat exchange part 51c flows from the upper part of the regeneration part 52 to the lower part, and carbon dioxide is separated by thermal energy. At this time, some of the ammonia aqueous solution in the regeneration unit 52 flows into the reboiler 56 through the circulation line 52a and is heated, and carbon dioxide and steam generated from the ammonia aqueous solution by heating of the reboiler 56 are It is supplied to the regeneration unit 52 through the circulation line 52a, thereby providing additional heat energy and increasing the separation efficiency of carbon dioxide. As described above, the ammonia aqueous solution supplied to the regeneration unit 52 is heated in the heat exchange unit 51c, and carbon dioxide and steam generated from the ammonia aqueous solution heated in the reboiler 56 provide additional heat energy. , carbon dioxide can be easily separated from ammonia aqueous solution. The high concentration of carbon dioxide separated from the aqueous ammonia solution is discharged to the top of the regeneration unit 52 and sequentially passes through the condenser 52b and the reflux drum 52c to remove moisture, and the moisture separated from the carbon dioxide is pressurized and returned to the regeneration unit 52. ) can be circulated.

The above-described first circulation pipe (53a) circulates the ammonia aqueous solution from which the carbon dioxide discharged from the regeneration unit 52 is separated to the absorption unit 51, and on the first circulation pipe (53a), the above-described heat exchange unit 51c and , pump 531, and cooler 532 may be installed. The ammonia aqueous solution from which the carbon dioxide is separated at about 80 to 150°C discharged from the regeneration unit 52 and flowing through the first circulation pipe 53a exchanges heat with the ammonia aqueous solution flowing through the supply line 51a in the heat exchange unit 51c. It is first cooled, pressurized by the pump 531, and then secondarily cooled by the cooler 532 and supplied to the absorption unit 51 at about 30 to 50°C.

Meanwhile, a second circulation pipe 53b may be branched from the first circulation pipe 53a in front of the heat exchange unit 51c. The second circulation pipe (53b) circulates the ammonia aqueous solution from which carbon dioxide has been separated in the regeneration unit 52 to the absorption unit 51 independently of the first circulation pipe (53a), and can be opened when the ammonia aqueous solution is contaminated. . That is, the circulation pipe for circulating the ammonia aqueous solution from which carbon dioxide is separated in the regeneration section 52 to the absorption section 51 includes a first circulation pipe 53a and a second circulation pipe 53b. To measure the degree of contamination of the aqueous ammonia solution, a sensor (S) may be installed on the first circulation pipe (53a) in front of the second circulation pipe (53b), and the second circulation pipe (53b) is linked with the sensor (S). It can be opened and closed. A separation unit 54 is installed on the second circulation pipe 53b, and the separation unit 54 uses the difference in specific gravity to separate the precipitate contained in the ammonia aqueous solution, for example, NH ₄ HCO, which is a solid salt. ₃ , NH ₂ COONH ₄ , (NH ₄ )2CO ₃ can be separated. As the separation unit 54 separates the sediment contained in the ammonia aqueous solution, the ammonia aqueous solution can be regenerated, thereby preventing the carbon dioxide absorption effect from being reduced due to the sediment. The ammonia aqueous solution from which the sediment has been removed in the separation unit 54 joins the first circulation pipe (53a) at the front or rear end of the pump 531 through the second circulation pipe (53b) and is circulated to the absorption unit (51), where it is separated. Sediment within unit 54 may be discharged overboard when the ammonia-propelled vessel 1 is docked.

Hereinafter, with reference to FIGS. 3 to 5, the operation of the ammonia propulsion vessel 1 will be described in more detail.

Figures 3 to 5 are operational diagrams for explaining the operation of an ammonia-propelled ship.

The ammonia-propelled ship (1) according to the present invention mixes liquid ammonia and liquid fuel and uses it as fuel for the combustion engine (40), so the amount of carbon dioxide contained in the exhaust gas can be reduced compared to the conventional case of using only liquid fuel. there is. In particular, it is possible to create an eco-friendly ship by reducing carbon dioxide emissions without using hydrogen, which is difficult to store and process, as a fuel. In addition, because liquid ammonia is used as a carbon dioxide absorbent, the cost of purchasing the absorbent can be reduced, and carbon dioxide contained in exhaust gas can be removed, making it possible to easily satisfy the International Maritime Organization's emission regulations.

First, referring to FIG. 3, liquid ammonia stored in the first fuel tank 20 is supplied to the combustion engine 40 through the first fuel supply pipe 21, and liquid fuel stored in the second fuel tank 30 is supplied to the combustion engine 40 through the first fuel supply pipe 21. It is supplied to the combustion engine (40) through the second fuel supply pipe (31). Liquid ammonia flows through the first fuel supply pipe 21 and at least part of it may be vaporized. Some of the liquid ammonia flows along the first fuel supply pipe 21 and the remaining part branches into the fuel branch pipe 22. Liquid ammonia branched into the fuel branch pipe 22 or ammonia vaporized from liquid ammonia may be mixed with fresh water flowing from the stirrer 60 to the fresh water supply pipe 70 to form an ammonia aqueous solution.

The combustion engine 40 generates power by receiving liquid ammonia or ammonia, and the exhaust gas generated by combustion of fuel flows through the first exhaust pipe 41a and the second exhaust pipe 42a, as shown in FIG. 4. It is supplied to the absorption part 51 of the carbon dioxide collection device 50 and comes into gas-liquid contact with the ammonia aqueous solution supplied through the fuel branch pipe 22. As a result, carbon dioxide contained in the exhaust gas is absorbed into the ammonia solution, and the exhaust gas from which the carbon dioxide has been removed undergoes a separate cooling process at the upper part of the absorption unit 51 and is then discharged to the outside through the exhaust pipe 40a. The aqueous ammonia solution that absorbs carbon dioxide is discharged to the supply line (51a), pressurized by the pump (51b), and then exchanges heat with the aqueous ammonia solution that circulates to the absorption unit (51) through the first circulation pipe (53a) in the heat exchanger (51c). After being heated, it is supplied to the regeneration unit 52. The ammonia aqueous solution that absorbs the carbon dioxide supplied to the regeneration unit 52 flows from the top to the bottom of the regeneration unit 52, and carbon dioxide is separated by thermal energy, and some of the ammonia aqueous solution from which the carbon dioxide is separated flows through the circulation line 52a. It flows into the reboiler 56, is heated, and then is supplied again to the regeneration unit 52. The remaining part of the ammonia aqueous solution from which the carbon dioxide has been separated moves to the heat exchanger (51c) through the first circulation pipe (53a) and is primarily cooled. After being pressurized in the pump (531), it is secondarily cooled in the cooler (532) and absorbed. It is supplied to unit 51. When the ammonia aqueous solution is circulated to the absorption unit 51 through the first circulation pipe 53a, the supply of the ammonia aqueous solution through the fuel branch pipe 22 may be stopped. If the contamination level of the ammonia solution measured by the sensor (S) is less than the standard value, the ammonia solution is circulated through the first circulation pipe (53a), and the second circulation pipe (53b) is closed.

High-concentration carbon dioxide separated from the aqueous ammonia solution is discharged to the upper part of the regeneration unit 22, passes through the condenser 52b and the reflux drum 52c in order, and is supplied as needed after moisture is removed. The moisture separated from the carbon dioxide is pressurized. It is circulated back to the reproduction unit 52.

On the other hand, when ammonia aqueous solution is circulated and used for a long period of time, the degree of contamination increases due to sediment, etc., which may reduce the carbon dioxide absorption effect. If the contamination level of the ammonia solution measured by the sensor (S) exceeds the standard value, as shown in FIG. 5, the second circulation pipe (53b) is opened to allow carbon dioxide discharged from the regeneration unit (52) to be discharged from the separated ammonia solution. A portion is supplied to the separation unit (54). The separation unit 54 separates the sediment contained in the ammonia aqueous solution using the difference in specific gravity, and the ammonia aqueous solution from which the sediment is separated passes through the second circulation pipe 53b to the first circulation pipe ( 53a), cooled in the cooler 532, and then circulated to the absorption unit 51.

Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will be able to understand it. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

1: Ammonia-propelled vessels
10: Hull 20: First fuel tank
21: first fuel supply pipe 22: fuel branch pipe
30: second fuel tank 31: second fuel supply pipe
40: combustion engine 40a: exhaust pipe
41: main engine 41a: first exhaust pipe
42: engine for power generation 42a: second exhaust pipe
50: Carbon dioxide capture device 51: Absorption unit
52: Regeneration unit 53a: First circulation pipe
53b: second circulation pipe 54: separation unit
60: Agitator 70: Fresh water supply pipe

Claims (5)

hull;
A first fuel tank installed on the hull and storing liquid ammonia therein;
A second fuel tank installed on the hull and storing liquid fuel therein;
A combustion engine that receives the liquid ammonia or ammonia vaporized by the liquid ammonia from the first fuel tank and generates power by receiving the liquid fuel from the second fuel tank, and
An ammonia-propelled vessel including a carbon dioxide capture device for removing carbon dioxide contained in exhaust gas generated from the combustion engine. According to claim 1,
The carbon dioxide capture device is an ammonia-propelled ship that is supplied with the liquid ammonia or an ammonia aqueous solution mixed with the ammonia and fresh water. According to clause 2,
An ammonia-propelled vessel installed between the first fuel tank and the carbon dioxide collection device, further comprising an agitator for mixing the liquid ammonia or the ammonia and the fresh water. The method of claim 2, wherein the carbon dioxide capture device,
An absorption unit that injects the ammonia aqueous solution into the exhaust gas supplied from the combustion engine,
An ammonia propulsion vessel comprising a regeneration unit that receives the ammonia aqueous solution in which carbon dioxide is absorbed from the absorption unit and separates carbon dioxide from the ammonia aqueous solution. The method of claim 4, wherein the carbon dioxide capture device,
A circulation pipe for circulating the ammonia aqueous solution from which carbon dioxide is separated in the regeneration unit to the absorption unit, and
An ammonia propulsion vessel installed on the circulation pipe and further comprising a separation unit that separates sediment contained in the ammonia aqueous solution using a difference in specific gravity.