KR20230154357A - Ammonia fuel vessel - Google Patents

Abstract

An ammonia fueled vessel is provided by one embodiment of the present invention.
An ammonia-fueled ship according to an embodiment of the present invention includes a hull, a fuel tank installed on the hull and storing liquid ammonia, and a main vessel that receives liquid ammonia from the fuel tank through a first fuel supply pipe and burns it to generate power. An engine, a boiler that receives liquid ammonia or ammonia generated by vaporizing liquid ammonia from a fuel tank through a second fuel supply pipe and burns it to generate steam, and a first fuel supply pipe and a second fuel supply pipe are connected to each other to create a first fuel supply pipe. Ammonia generated by vaporization of liquid ammonia or liquid ammonia remaining in the fuel supply pipe or main engine is supplied to the boiler, or ammonia generated by vaporization of liquid ammonia or liquid ammonia remaining in the second fuel supply pipe or boiler is supplied to the main engine. It may include a recovery pipe.

Description

Ammonia fuel vessel

The present invention relates to an ammonia-fueled ship, and more specifically, to an ammonia-fueled ship that can effectively treat ammonia remaining in the piping and engine side or boiler side when an engine or boiler malfunctions.

In general, various engines installed on ships generate power by burning fossil fuels, and exhaust gases generated during the combustion process of fuel contain nitrogen oxides, sulfur oxides, carbon dioxide, etc. As air pollution due to pollutants contained in exhaust gases increases, there is a demand for the development of eco-friendly ships that generate power using low-carbon or decarbonized fuels. Ammonia, which does not emit carbon dioxide when burned, is one of the next-generation eco-friendly fuels. It is emerging.

On the other hand, in conventional ships that use ammonia as fuel for engines and boilers, when the engine or boiler is shut down or tripped (automatically opens the circuit breaker), the fuel in the piping that supplies ammonia, the engine, and the boiler side. The residue was quickly purged and released to the atmosphere. However, ammonia is a toxic substance and does not disperse instantly when released into the atmosphere, so releasing ammonia into the atmosphere poses a safety issue. Accordingly, a method of dissolving ammonia in water to lower its concentration and then releasing it has been proposed, but it is difficult to dissolve a large amount of ammonia in a certain amount of water in the tank, and the pH of the water in which ammonia is dissolved is high, so it cannot be discharged as is into the sea. There are also problems that are difficult to deal with.

Accordingly, there is a need for a ship that can effectively treat ammonia remaining in the piping and engine side or boiler side when an engine or boiler malfunctions.

Republic of Korea Patent Publication No. 10-2022-0034270 (2022.03.18.)

The technical problem to be achieved by the present invention is to provide an ammonia fuel vessel that can effectively treat ammonia remaining in the piping and on the engine side or boiler side when an engine or boiler malfunctions.

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 fuel ship according to an embodiment of the present invention for achieving the above technical problem includes a hull, a fuel tank installed on the hull and storing liquid ammonia, and a first fuel supply pipe that supplies the liquid ammonia from the fuel tank. A main engine that receives supply and burns it to generate power, a boiler that receives the liquid ammonia or ammonia generated by vaporizing the liquid ammonia from the fuel tank through a second fuel supply pipe and burns it to generate steam, and the first fuel supply pipe. The fuel supply pipe and the second fuel supply pipe are connected to each other to supply the liquid ammonia remaining in the first fuel supply pipe or the main engine or ammonia generated by vaporization of the liquid ammonia to the boiler, or the second fuel supply pipe or It includes a recovery pipe that supplies the liquid ammonia remaining in the boiler or the ammonia generated by vaporizing the liquid ammonia to the main engine.

The ammonia fuel vessel includes a pollutant reduction device installed in the exhaust pipe of at least one of the main engine and the boiler to reduce at least one of nitrous oxide and nitrogen oxide contained in the exhaust gas, and a pollutant reduction device branched from the return pipe to discharge the main It may further include a branch pipe for providing the liquid ammonia or the ammonia remaining in the engine or the boiler as a reducing agent to the pollutant reduction device.

The ammonia fuel vessel further includes a reducing agent supply pipe that connects the fuel tank and the pollutant reduction device to supply the liquid ammonia or the ammonia to the pollutant reduction device as a reducing agent, wherein the branch pipe is connected to the reducing agent supply pipe. The liquid ammonia or the ammonia can be supplied.

The pollutant reduction device includes a first selective catalytic reduction reactor for removing the nitrous oxide, and a second selective catalytic reduction reactor installed at a rear end of the first selective catalytic reduction reactor to remove the nitrogen oxides. The engine includes a first branch pipe for supplying the liquid ammonia or the ammonia to a first reducing agent supply pipe connected to the first selective catalytic reduction reactor, and a second reducing agent supply pipe connected to the second selective catalytic reduction reactor to provide the liquid phase. It may include ammonia or a second branch pipe for supplying the ammonia.

The first selective catalytic reduction reactor is a catalyst in which at least one of cobalt (Co), rhodium (Rh), and cerium-cobalt complex oxide (Ce-Co-O) is supported on a carrier made of aluminum oxide (Al ₂ O ₃ ). , or a catalyst in which rhodium (Rh) is supported on a carrier made of aluminum oxide (Zn-Al ₂ O ₃ ) impregnated with zinc, or a catalyst in which iron (Fe) is supported on a carrier made of zeolite, When the liquid ammonia or the ammonia is supplied as a reducing agent, the nitrous oxide can be reduced to nitrogen and oxygen.

In the ammonia fuel ship, the first fuel supply pipe and the second fuel supply pipe each include a pretreatment device for preprocessing the liquid ammonia, and the recovery pipe can supply the liquid ammonia or the ammonia to the front of the pretreatment device. there is.

The ammonia fuel vessel has an exhaust gas circulation pipe branched from the exhaust pipe of the boiler to circulate exhaust gas to the air supply pipe of the boiler, and an exhaust gas circulation pipe branched from the return pipe to supply the liquid ammonia or the ammonia to the exhaust gas circulation pipe. It may further include a water exchange pipe.

According to the present invention, when the main engine malfunctions, the ammonia remaining in the first fuel supply pipe or the main engine is recovered and supplied to the boiler, and when the boiler malfunctions, the ammonia remaining in the second fuel supply pipe or boiler is recovered and supplied to the main engine. In addition, when the main engine and boiler malfunction, the recovered ammonia is supplied to the boiler and incinerated, so ammonia can be effectively treated without a separate ammonia vent system and space utilization within the ship can be increased.

1 is a diagram schematically showing an ammonia-fueled ship according to an embodiment of the present invention.
FIG. 2 is an enlarged view of the first selective catalytic reduction reactor of FIG. 1.
Figures 3 to 5 are operational diagrams for explaining the operation of an ammonia fuel ship according to an embodiment of the present invention.
Figure 6 is a diagram schematically showing an ammonia-fueled ship according to another embodiment of the present invention.
Figures 7 and 8 are operational diagrams for explaining the operation of an ammonia fuel ship according to another embodiment of the present invention.

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-fueled ship according to an embodiment of the present invention will be described in detail.

The ammonia fuel ship according to an embodiment of the present invention is a ship that uses ammonia as fuel. For example, ammonia can be supplied as fuel to combustion engines and boilers to generate propulsion, electricity, steam, etc.

In ammonia-fueled ships, when the main engine malfunctions, the ammonia remaining in the first fuel supply pipe or main engine is recovered and supplied to the boiler. When the main engine and boiler malfunction, the recovered ammonia is supplied to the boiler and incinerated, so a separate ammonia vent is required. It has the feature of not only being able to effectively treat ammonia without a system, but also increasing space utilization within the ship.

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

Figure 1 is a diagram schematically showing an ammonia fuel ship according to an embodiment of the present invention, and Figure 2 is an enlarged diagram of the first selective catalytic reduction reactor of Figure 1.

The ammonia fuel ship 1 according to the present invention includes a hull 10, a fuel tank 20, a main engine 30, a boiler 40, and a recovery pipe 50A.

The hull 10 forms the external shape of the ammonia fuel ship 1, and the outer surface is formed in a streamlined shape to minimize resistance due to seawater. The hull 10 is propelled by power generated from the main engine 30, which will be described later, and at least one fuel tank 20 is installed therein.

The fuel tank 20 is a tank that stores liquid ammonia and may be formed as a membrane-type normal pressure tank in which the internal pressure is maintained constant. Liquid ammonia stored in the fuel tank 20 can be supplied to the main engine 30 and boiler 40, respectively.

The main engine 30 receives liquid ammonia from the fuel tank 20 through the first fuel supply pipe 31 and burns it to generate power, and one end of the first fuel supply pipe 31 penetrates the fuel tank 20. Thus, it is connected to the low pressure pump 21 installed inside the fuel tank 20, and the other end can be extended outside the fuel tank 20 and connected to the main engine 30. A pretreatment device 32 is installed on the first fuel supply pipe 31 to preprocess the liquid ammonia by pressurizing and heating it. The pretreatment device 32 includes a boosting pump for pressurizing the liquid ammonia and a heat exchanger for heating the liquid ammonia. can do. In the drawing, a single boosting pump and a heat exchanger are installed on the first fuel supply pipe 31, and the heat exchanger is shown as installed at the rear of the boosting pump. However, this is not limited to this, and the number and arrangement of the boosting pump and heat exchanger are determined as necessary. It may be modified accordingly.

The boiler 40 receives liquid ammonia or ammonia generated by vaporizing liquid ammonia from the fuel tank 20 through the second fuel supply pipe 41 and burns it to generate steam. Hereinafter, the structure in which the boiler 40 receives liquid ammonia and burns it to generate steam will be described in more detail. One end of the second fuel supply pipe 41 may be connected to the low pressure pump 21 and the other end may extend outside the fuel tank 20 and be connected to the boiler 40 . A pretreatment device 42 is installed on the second fuel supply pipe 41 to heat and preprocess liquid ammonia, and the pretreatment device 42 may include a heat exchanger to heat liquid ammonia. Although it is shown in the drawing that a single heat exchanger is installed on the second fuel supply pipe 41, it is not limited to this, and the number of heat exchangers can be added or subtracted as needed.

The main engine 30 and the boiler 40 each burn liquid ammonia to generate power and steam necessary for the ship, so that carbon dioxide is not generated and can satisfy the International Maritime Organization's carbon dioxide emission regulations.

The main engine 30 and boiler 40 may be shut-down or tripped (automatically opening the circuit breaker) while operating, and at this time, the first fuel supply pipe 31, the main engine 30, and the first fuel supply pipe 31 2 Liquid ammonia remaining in the fuel supply pipe (41) and boiler (40) or ammonia generated by vaporization of liquid ammonia must be quickly treated. The recovery pipe (50A) connects the first fuel supply pipe (31) and the second fuel supply pipe (41) to each other, so that the liquid ammonia or liquid ammonia remaining in the first fuel supply pipe (31) or the main engine (30) is vaporized. The generated ammonia can be supplied to the boiler 40, or the ammonia generated by vaporizing the liquid ammonia or liquid ammonia remaining in the second fuel supply pipe 41 or the boiler 40 can be supplied to the main engine 30. The recovery pipe (50A) supplies liquid ammonia or ammonia remaining in the first fuel supply pipe (31) or the main engine (30) to the boiler (40), or supplies the liquid ammonia or ammonia remaining in the second fuel supply pipe (41) or the boiler (40) to the boiler (40). By supplying liquid ammonia or ammonia to the main engine 30, ammonia can be effectively treated without a separate ammonia vent system and space utilization within the ship can also be increased. Hereinafter, the structure in which the recovery pipe 50A supplies liquid ammonia or ammonia remaining in the first fuel supply pipe 31 or the main engine 30 to the boiler 40 will be described in more detail. The recovery pipe (50A) is branched at one end and connected to the first fuel supply pipe (31) and the main engine (30), respectively, and the other end is connected to the second fuel supply pipe (41) in front of the preprocessing device (42), providing first fuel Liquid ammonia or ammonia remaining in the supply pipe 31 or the main engine 30 can be recovered and supplied to the front of the pretreatment device 42. Liquid ammonia or ammonia recovered through the recovery pipe 50A and supplied to the front of the pretreatment device 42 can be heated in the pretreatment device 42 and then supplied to the boiler 40 and used as fuel.

Meanwhile, the exhaust gas generated from the main engine 30 and the boiler 40 are discharged through the first exhaust pipe (E1) and the second exhaust pipe (E2), and the first exhaust pipe (E1) and the second exhaust pipe (E2) At least one of the pollutant reduction devices 60A and 60B may be installed to reduce at least one of nitrous oxide and nitrogen oxide contained in the exhaust gas. When burning liquid ammonia, carbon dioxide is not generated, but there is a problem in that nitrogen oxides and nitrous oxide are generated. Nitrogen oxides are air pollutants that cause plant death and acid rain, and nitrous oxides are greenhouse gases that cause global warming, so they need to be removed from exhaust gases. The pollutant reduction devices (60A, 60B) are formed as a catalytic reactor that reduces at least one of nitrous oxide and nitrogen oxide contained in the exhaust gas using liquid ammonia or ammonia as a reducing agent, and supplies liquid ammonia or ammonia to one side. Reducing agent supply pipes 70A and 70B may be connected. The reducing agent supply pipe (70A, 70B) connects the fuel tank (20) and the pollutant reduction device (60A, 60B) to transfer ammonia generated by vaporizing the liquid ammonia or liquid ammonia inside the fuel tank (20) to the pollutant reduction device ( 60A, 60B) can be supplied as a reducing agent. As described above, if the fuel tank 20 is formed as an atmospheric pressure tank, there is an advantage in reducing tank design cost and weight, but the internal pressure is not high, so liquid ammonia can easily vaporize naturally. Alternatively, liquid ammonia may naturally vaporize due to sloshing or the like. Ammonia generated by vaporization of liquid ammonia causes various problems, such as increasing the pressure inside the tank and accelerating the vaporization of liquid ammonia, so it is discharged through the reducing agent supply pipe (70A, 70B) to the pollutant reduction device (60A, 60B). can be supplied. Hereinafter, pollutant reduction devices (60A, 60B) are installed in the first exhaust pipe (E1) and the second exhaust pipe (E2), respectively, and the reducing agent supply pipes (70A, 70B) reduce ammonia inside the fuel tank 20 as a pollutant. The structure of supply to the devices 60A and 60B will be described in more detail.

The pollutant reduction devices (60A, 60B) include a first selective catalytic reduction reactor (61a, 61b) for removing nitrous oxide, a second selective catalytic reduction reactor (62a, 62b) for removing nitrogen oxide, and a reducing agent. The supply pipes (70A, 70B) are first reducing agent supply pipes (71a, 71b) connected to the first selective catalytic reduction reactors (61a, 61b), and second reducing agent supply pipes (71a, 71b) connected to the second selective catalytic reduction reactors (62a, 62b). It may include supply pipes 72a and 72b. Since the reaction temperature for reducing nitrous oxide in the first selective catalytic reduction reactor (61a, 61b) is higher than the reaction temperature for reducing nitrogen oxide in the second selective catalytic reduction reactor (62a, 62b), the second selective catalytic reduction reactor (62a, 62b) may be installed at the rear of the first selective catalytic reduction reactor (61a, 61b).

The first selective catalytic reduction reactor (61a, 61b) reduces nitrous oxide into nitrogen and oxygen by passing liquid ammonia or exhaust gas mixed with ammonia supplied through the first reducing agent supply pipe (71a, 71b) through a catalyst layer installed in the reactor. You can. As shown in FIG. 2, the catalyst layer may be formed in a honeycomb structure or a plate structure, and at least one catalyst layer may be installed inside the reactor. The catalyst layer is a catalyst in which at least one of cobalt (Co), rhodium (Rh), and cerium-cobalt composite oxide (Ce-Co-O) is supported on a carrier made of aluminum oxide (Al ₂ O ₃ ), or a catalyst impregnated with zinc. It may include a catalyst in which rhodium (Rh) is supported on a carrier made of aluminum oxide (Zn-Al ₂ O ₃ ), or a catalyst in which iron (Fe) is supported on a carrier made of zeolite.

The second selective catalytic reduction reactor (62a, 62b) can reduce nitrogen oxides to nitrogen and water by passing liquid ammonia or exhaust gas mixed with ammonia supplied through the second reducing agent supply pipe (72a, 72b) through a catalyst layer installed in the reactor. there is. The catalyst layer may be formed in a honeycomb structure or a plate structure, and at least one catalyst layer may be installed inside the reactor. Since the second selective catalytic reduction reactors 62a and 62b for reducing nitrogen oxides are a known technology, detailed description of the catalyst layer will be omitted.

A branch pipe 51A may be branched from the above-described recovery pipe 50A. The branch pipe (51A) uses liquid ammonia or ammonia remaining in the main engine (30) as a reducing agent to the pollutant reduction device (60B), more specifically, to the pollutant reduction device (60B) installed on the second exhaust pipe (E2). Through the supply pipe, the recovered liquid ammonia or ammonia can be supplied to the reducing agent supply pipe (70B). The branch pipe (51A) includes a first branch pipe (51a) for supplying liquid ammonia or ammonia to the first reducing agent supply pipe (71b), and a second branch pipe (51a) for supplying liquid ammonia or ammonia to the second reducing agent supply pipe (72b). 51b) may be included.

In addition, on the second exhaust pipe (E2), an exhaust gas circulation pipe 81 is branched for circulating part of the exhaust gas to the air supply pipe 80, and the recovered liquid ammonia or ammonia is distributed to the recovery pipe 50A through the exhaust gas circulation pipe. The water return pipe (52A) supplying to (81) may be branched. As the exhaust gas circulation pipe 81 is branched on the second exhaust pipe E2, the temperature of the combustion chamber of the boiler 40 is lowered due to the circulating exhaust gas, thereby suppressing the generation of nitrogen oxides. A cooler 82 that cools the exhaust gas may be installed on the exhaust gas circulation pipe 81. In the drawing, the water return pipe 52A is shown as connected to the exhaust gas circulation pipe 81 at the rear end of the cooler 82, but it is not limited to this, and if necessary, the water return pipe 52A is connected to the exhaust gas circulation pipe 81 at the rear end of the cooler 82. It may also be connected to the exhaust gas circulation pipe (81).

On the other hand, when the main engine 30 is not driven, the boiler 40 is stopped, and the pollutant reduction device 60B connected to the second exhaust pipe E2 is not driven, the pollutant reduction device 60B connected to the second exhaust pipe E2 is not operated. Liquid ammonia or ammonia can be supplied to the boiler 40 and incinerated. In other words, the boiler 40 can be used as a gas combustion unit (GCU) rather than its original function of generating steam to incinerate liquid ammonia or ammonia. The recovered liquid ammonia or ammonia may be supplied to the second fuel supply pipe 41 in front of the pretreatment device 42 through the recovery pipe 50A, and may be supplied to the exhaust gas circulation pipe 81 through the return pipe 52A. It could be.

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

Figures 3 to 5 are operational diagrams for explaining the operation of an ammonia fuel ship according to an embodiment of the present invention.

The ammonia fuel ship (1) according to the present invention recovers the ammonia remaining in the first fuel supply pipe (31) or the main engine (30) when the main engine (30) malfunctions and supplies it to the boiler (40), and the main engine ( 30) and the boiler 40, when the recovered ammonia is supplied to the boiler 40 and incinerated, not only can ammonia be effectively treated without a separate ammonia vent system, but space utilization within the ship can also be increased.

Figure 3 is an operation diagram for explaining the operation when the main engine and boiler are normally operated, Figure 4 is an operation diagram for explaining the operation when the main engine is abnormal, and Figure 5 is an operation diagram for explaining the operation when the main engine and boiler are abnormal. This is an operation diagram to explain.

First, referring to FIG. 3, the liquid ammonia stored in the fuel tank 20 is pressurized by the low pressure pump 21 and flows into the first fuel supply pipe 31 and the second fuel supply pipe 41, respectively, and the fuel tank ( Ammonia generated by vaporizing the liquid ammonia stored in 20) flows into the first reducing agent supply pipes (71a, 71b) and the second reducing agent supply pipes (72a, 72b), respectively.

Liquid ammonia flowing into the first fuel supply pipe 31 is pressurized and heated in the pretreatment device 32 and then supplied to the main engine 30, and the main engine 30 burns the liquid ammonia to generate power. The exhaust gas resulting from the combustion of liquid ammonia in the main engine 30 is discharged through the first exhaust pipe (E1) and supplied to the first selective catalytic reduction reactor (61a), and the first selective catalytic reduction reactor (61a) uses the first reducing agent. Ammonia supplied through the supply pipe 71a is used as a reducing agent to reduce nitrous oxide to nitrogen and oxygen. The exhaust gas from which nitrous oxide has been removed is supplied to the second selective catalytic reduction reactor (62a), which uses ammonia supplied through the second reducing agent supply pipe (72a) as a reducing agent to reduce nitrogen oxides. Reduced to nitrogen and water. The exhaust gas from which nitrogen oxides have been removed is discharged into the atmosphere through the first exhaust pipe (E1).

Liquid ammonia flowing into the second fuel supply pipe 41 is heated in the pretreatment device 42 and then supplied to the boiler 40, and the boiler 40 burns the liquid ammonia to generate steam. The exhaust gas resulting from the combustion of liquid ammonia in the boiler 40 is discharged through the second exhaust pipe (E2) and part of it is supplied to the first selective catalytic reduction reactor (61b). Ammonia supplied through the reducing agent supply pipe (71b) is used as a reducing agent to reduce nitrous oxide to nitrogen and oxygen. The exhaust gas from which nitrous oxide has been removed is supplied to the second selective catalytic reduction reactor (62b), which uses ammonia supplied through the second reducing agent supply pipe (72b) as a reducing agent to reduce nitrogen oxides. Reduced to nitrogen and water. The exhaust gas from which nitrogen oxides have been removed is discharged into the atmosphere through the second exhaust pipe (E2). The remaining part of the exhaust gas discharged through the second exhaust pipe (E2) branches off to the exhaust gas circulation pipe (81), is cooled in the cooler (82), and then circulates to the air supply pipe (80).

Next, referring to FIG. 4, the boiler 40 is operated normally and when the main engine 30 malfunctions, the liquid ammonia remaining in the first fuel supply pipe 31 and the main engine 30 is returned to the recovery pipe 50A. It can be recovered. The liquid ammonia recovered through the recovery pipe (50A) is supplied to the second fuel supply pipe (41) in front of the pretreatment device (42) and used as fuel for the boiler (40), or the first branch pipe (51a) and the second branch pipe. It can be supplied to the first reducing agent supply pipe (71b) and the second reducing agent supply pipe (72b) through (51b) and used as a reducing agent. When liquid ammonia is supplied to the first reducing agent supply pipe (71b) and the second reducing agent supply pipe (72b) through the first branch pipe (51a) and the second branch pipe (51b), the first reducing agent supply pipe (71b) and the second reducing agent supply pipe (71b) The reducing agent supply pipe 72b may stop supplying ammonia from the fuel tank 20. Liquid ammonia supplied to the first selective catalytic reduction reactor (61b) and the second selective catalytic reduction reactor (62b) can be used as a reducing agent to reduce nitrous oxide and nitrogen oxide.

Next, referring to FIG. 5, when the main engine 30 and the boiler 40 malfunction, the liquid ammonia remaining in the first fuel supply pipe 31 and the main engine 30, respectively, is recovered into the recovery pipe 50A. It may be supplied to the second fuel supply pipe 41 in front of the pretreatment device 42, or may be supplied to the exhaust gas circulation pipe 81 through the return pipe 52A and incinerated in the boiler 40. Additionally, the liquid ammonia remaining in the second fuel supply pipe 41 and the boiler 40 may also be incinerated in the boiler 40.

Hereinafter, with reference to FIGS. 6 and 7, the ammonia vessel 1-1 according to another embodiment of the present invention will be described in more detail.

Figure 6 is a diagram schematically showing an ammonia fuel ship according to another embodiment of the present invention, and Figures 7 and 8 are operational diagrams for explaining the operation of an ammonia fuel ship according to another embodiment of the present invention.

In the ammonia fuel ship 1-1 according to another embodiment of the present invention, when the boiler 40 malfunctions, the recovery pipe 50B recovers the liquid ammonia remaining in the second fuel supply pipe 41 or the boiler 40. It is supplied to the main engine (30). In the ammonia fuel ship 1-1 according to another embodiment of the present invention, when the boiler 40 malfunctions, the recovery pipe 50B recovers the liquid ammonia remaining in the second fuel supply pipe 41 or the boiler 40. Except for supply to the main engine 30, it is substantially the same as the above-described embodiment. Therefore, this will be mainly explained, but unless otherwise stated, the description of the remaining components will be replaced by the above-mentioned details.

The recovery pipe (50B) is branched at one end and connected to the second fuel supply pipe (41) and the boiler (40), respectively, and the other end is connected to the first fuel supply pipe (31) in front of the pretreatment device (32), thereby forming the second fuel supply pipe. (41) Alternatively, the liquid ammonia remaining in the boiler 40 can be recovered and supplied to the front of the pretreatment device 32. The liquid ammonia recovered through the recovery pipe 50B and supplied to the front of the pretreatment device 32 is pressurized and heated in the pretreatment device 32 and then supplied to the main engine 30 to be used as fuel. A branch pipe 51B may be branched from this recovery pipe 50B. The branch pipe 51B is a pipe that supplies liquid ammonia remaining in the boiler 40 as a reducing agent to the pollutant reduction device 60A, more specifically, to the pollutant reduction device 60A installed on the first exhaust pipe E1. In this way, the recovered liquid ammonia can be supplied to the reducing agent supply pipe (70A). The branch pipe (51B) is connected to the first branch pipe (51a) that supplies liquid ammonia to the first reducing agent supply pipe (71a) connected to the first selective catalytic reduction reactor (61a) and the second selective catalytic reduction reactor (62a). It may include a second branch pipe (51b) that supplies liquid ammonia to the second reducing agent supply pipe (72a).

In addition, the return pipe 52B branched from the return pipe 50B is connected to the exhaust gas circulation pipe 81, so that the recovered liquid ammonia can be supplied to the exhaust gas circulation pipe 81. In the drawing, the water return pipe 52B is shown as being connected to the exhaust gas circulation pipe 81 at the rear end of the cooler 82, but it is not limited to this, and if necessary, the water return pipe 52B is connected to the exhaust gas circulation pipe 81 at the rear end of the cooler 82. It may also be connected to the exhaust gas circulation pipe (81).

On the other hand, when the boiler 40 is not driven and the main engine 30 is stopped and the pollutant reduction device 60A connected to the first exhaust pipe E1 is not driven, the liquid recovered into the recovery pipe 50B Ammonia can be supplied to the boiler 40 through the water return pipe 52B and incinerated. In other words, the boiler 40 can be used as a gas incineration device rather than its original function of generating steam to incinerate liquid ammonia.

Figure 7 is an operation diagram for explaining the operation when the boiler malfunctions, and Figure 8 is an operation diagram for explaining the operation when the main engine and boiler are malfunctioning.

First, referring to FIG. 7, the main engine 30 is operated normally and when the boiler 40 malfunctions, the liquid ammonia remaining in the second fuel supply pipe 41 and the boiler 40 is transferred to the recovery pipe 50B. It can be recovered. The liquid ammonia recovered through the recovery pipe (50B) is supplied to the first fuel supply pipe (31) in front of the pretreatment device (32) and used as fuel for the main engine (30), or is used as fuel for the main engine (30) or the first branch pipe (51a) and the second fuel supply pipe (31). It can be supplied to the first reducing agent supply pipe (71a) and the second reducing agent supply pipe (72a) through the engine (51b) and used as a reducing agent. When liquid ammonia is supplied to the first reducing agent supply pipe (71a) and the second reducing agent supply pipe (72a) through the first branch pipe (51a) and the second branch pipe (51b), the first reducing agent supply pipe (71a) and the second reducing agent supply pipe (71a) The reducing agent supply pipe 72a may stop supplying ammonia from the fuel tank 20. Liquid ammonia supplied to the first selective catalytic reduction reactor (61a) and the second selective catalytic reduction reactor (62a) can be used as a reducing agent to reduce nitrous oxide and nitrogen oxide.

Next, referring to FIG. 8, when the main engine 30 and the boiler 40 malfunction, the liquid ammonia remaining in the second fuel supply pipe 41 and the boiler 40 is recovered into the recovery pipe 50B and then It can be supplied to the exhaust gas circulation pipe 81 through the water return pipe 52B and incinerated in the boiler 40.

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, 1-1: Ammonia fueled ships
10: Hull 20: Fuel tank
21: low pressure pump 30: main engine
31: first fuel supply pipe 32: pretreatment device
40: Boiler 41: Second fuel supply pipe
42: Pretreatment device 50A, 50B: Recovery pipe
51A, 51B: branch pipe 51a: first branch pipe
51b: second branch pipe 52A, 52B: water return pipe
60A, 60B: Pollutant reduction device 61a, 61b: First selective catalytic reduction reactor
62a, 62b: second selective catalytic reduction reactor
70A, 70B: reducing agent supply pipe 71a, 71b: first reducing agent supply pipe
72a, 72b: second reducing agent supply pipe 80: air supply pipe
81: exhaust gas circulation pipe 82: cooler
E1: 1st exhaust pipe E2: 2nd exhaust pipe

Claims (7)

hull;
A fuel tank installed on the hull and storing liquid ammonia;
A main engine that receives the liquid ammonia from the fuel tank through a first fuel supply pipe and burns it to generate power;
A boiler that receives the liquid ammonia or ammonia generated by vaporizing the liquid ammonia from the fuel tank through a second fuel supply pipe and burns it to generate steam, and
The first fuel supply pipe and the second fuel supply pipe are connected to each other to supply the liquid ammonia remaining in the first fuel supply pipe or the main engine or ammonia generated by vaporization of the liquid ammonia to the boiler, or to supply the liquid ammonia remaining in the first fuel supply pipe or the main engine to the boiler. An ammonia fuel ship comprising a fuel supply pipe or a recovery pipe for supplying the liquid ammonia remaining in the boiler or ammonia generated by vaporization of the liquid ammonia to the main engine. According to claim 1,
A pollutant reduction device installed in the exhaust pipe of at least one of the main engine and the boiler to reduce at least one of nitrous oxide and nitrogen oxide contained in exhaust gas, and
An ammonia fuel ship further comprising a branch pipe branched from the recovery pipe to provide the liquid ammonia or the ammonia remaining in the main engine or the boiler as a reducing agent to the pollutant reduction device. According to clause 2,
It further includes a reducing agent supply pipe connecting the fuel tank and the pollutant reduction device to supply the liquid ammonia or the ammonia to the pollutant reduction device as a reducing agent,
The branch pipe is an ammonia fuel ship that supplies the liquid ammonia or the ammonia to the reducing agent supply pipe. According to clause 3,
The pollutant reduction device includes a first selective catalytic reduction reactor for removing the nitrous oxide, and a second selective catalytic reduction reactor installed at a rear end of the first selective catalytic reduction reactor to remove the nitrogen oxides,
The branch pipe includes a first branch pipe that supplies the liquid ammonia or the ammonia to a first reducing agent supply pipe connected to the first selective catalytic reduction reactor, and a second reducing agent supply pipe connected to the second selective catalytic reduction reactor. An ammonia fuel vessel comprising a second branch pipe for supplying the liquid ammonia or the ammonia. The method of claim 4, wherein the first selective catalytic reduction reactor,
A catalyst containing at least one of cobalt (Co), rhodium (Rh), and cerium-cobalt composite oxide (Ce-Co-O) supported on a carrier made of aluminum oxide (Al ₂ O ₃ ), or aluminum oxide impregnated with zinc ( Including a catalyst in which rhodium (Rh) is supported on a carrier made of Zn-Al ₂ O ₃ ), or a catalyst in which iron (Fe) is supported on a carrier made of zeolite,
An ammonia fuel ship in which the nitrous oxide is reduced to nitrogen and oxygen when the liquid ammonia or the ammonia is supplied as a reducing agent. According to claim 1,
The first fuel supply pipe and the second fuel supply pipe each include a pretreatment device for preprocessing the liquid ammonia,
The recovery pipe is an ammonia fuel ship that supplies the liquid ammonia or the ammonia to the front of the pretreatment device. According to claim 1,
An exhaust gas circulation pipe that branches off from the exhaust pipe of the boiler and circulates exhaust gas to the air supply pipe of the boiler, and
Ammonia fuel vessel further comprising a water return pipe branched from the return pipe to supply the liquid ammonia or the ammonia to the exhaust gas circulation pipe.

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