Device for producing hydrogen from ammonia for ship

Abstract

The present invention relates to a device for producing hydrogen from ammonia for a ship. According to the present invention, high-pressure hydrogen can be produced by using liquefied ammonia for a ship, and hydrogen can be economically produced by utilizing unconverted ammonia discharged from a decomposition reactor and off-gas discharged from a pressure swing adsorption device as a heat source for ammonia decomposition through a heat exchange network of the ship.

Description

Device for producing hydrogen from ammonia for ships

[0001] The present invention relates to a device for producing hydrogen from ammonia for use in ships.

[0002] Significant efforts are underway to protect the environment and achieve sustainable energy production. As part of these efforts, natural gas is being supplied as city gas by mixing 10 to 30% hydrogen with it to expand hydrogen supply. Furthermore, since the only byproduct produced during hydrogen combustion is water vapor, mixing hydrogen with city gas can reduce carbon dioxide emissions.

[0003] With the recent global goal of carbon neutrality in relation to climate change, hydrogen (H2) has been gaining more attention, and efforts to produce hydrogen are ongoing due to its potential for use in a variety of applications.

[0004] The natural gas reforming process, which uses fossil fuels such as heavy oil and natural gas, or byproduct hydrogen generated during steel mills or petrochemical processes as an energy source, re-emit carbon dioxide during the hydrogen production process. Therefore, the importance of a hydrogen production process using ammonia, which does not generate carbon dioxide during the reaction process, is gradually increasing.

[0005] In particular, ammonia is 120 kg / m 3 It is being emphasized as an essential technology for achieving carbon neutrality as it can utilize existing storage and transportation infrastructure almost as is as an ultra-high-capacity hydrogen storage and transport vehicle with a storage capacity of .

[0006] However, conventional processes for producing hydrogen from ammonia require significant land area due to the need for large-capacity tanks and related utility resources. Furthermore, because ammonia is a toxic gas, the risks associated with onshore sites and environmental impact assessments must be considered.

[0007] Prior art literature on an ammonia-fueled power generation system developed for ships (Korean Patent Application No. 10-2022-0034458) stores liquid ammonia at temperatures between -33°C and 30°C and pressures between 10 and 15 bara. However, to produce large-scale hydrogen, a system capable of supplying ammonia at pressures between 30 and 90 barg is required. Furthermore, to implement a large-scale hydrogen supply system, the ammonia storage device must be modularly installed onboard (topside) and designed to take into account heating and cooling utilities available from the ship's hull.

[0008] (Patent Document 1) Korean Patent Application No. 10-2022-0034458

[0009] The present invention aims to produce high-pressure hydrogen using liquefied ammonia in a ship.

[0010] The present invention can economically produce hydrogen by utilizing un-decomposed ammonia discharged from a decomposition reactor and off-gas discharged from a pressure swing adsorption device as a heat source for ammonia decomposition through a ship's heat exchange network.

[0011] The hydrogen production device of the present invention can produce a large amount of hydrogen in a minimal area by utilizing the infrastructure of a ship.

[0012] According to one embodiment of the present invention, a hydrogen production device comprises: a ship ammonia storage tank; a tank pump for pressurizing liquid ammonia inside the ship ammonia storage tank and supplying it to a suction drum; a suction drum for stabilizing the pressure of liquid ammonia supplied from the tank pump and supplying it to a pressurizing pump; a pressurizing pump for pressurizing and vaporizing liquid ammonia supplied from the suction drum and supplying the produced gaseous ammonia to a distributor; a distributor for distributing and supplying gaseous ammonia supplied from the pressurizing pump to a decomposition reactor and a combustor; a combustor for combusting gaseous ammonia supplied from the distributor and supplying heat to the decomposition reactor; a decomposition reactor for decomposing gaseous ammonia supplied from the distributor into hydrogen and nitrogen at 400 to 900°C in the presence of a catalyst; a pressure swing absorption (PSA) device for receiving off-gas discharged from the decomposition reactor and separating hydrogen; And it includes a denitrification reactor that receives off-gas discharged from the combustor and decomposes nitrogen oxides into nitrogen and water vapor.

[0013] The above hydrogen production device may have a conversion rate of 80% or more for the ammonia decomposition reaction occurring in the decomposition reactor.

[0014] The above hydrogen production device may include two or more of the pressure swing adsorption devices.

[0015] The hydrogen production device may include a first pressure swing adsorption device that receives off-gas discharged from the decomposition reactor and adsorbs ammonia; and a second pressure swing adsorption device that receives off-gas discharged from the first pressure swing adsorption device and adsorbs nitrogen.

[0016] The above hydrogen production device may further include a purge gas supply line that supplies off-gas discharged from the second pressure swing adsorption device as purge gas to the first pressure swing adsorption device.

[0017] The above distributor distributes and supplies gaseous ammonia supplied from the pressurized pump to a decomposition reactor, a combustion reactor, and a denitrification reactor, and the denitrification reactor can use the gaseous ammonia supplied from the distributor as a reducing agent.

[0018] The above hydrogen production device may further include a first low-pressure heat recovery heat exchanger in front of the combustor.

[0019] The above hydrogen production device may further include a second low-pressure heat recovery heat exchanger at the rear end of the denitrification reactor.

[0020] The above hydrogen production device may further include a high-pressure heat recovery heat exchanger in front of the decomposition reactor.

[0021] The above hydrogen production device may further include a first heat exchanger at a rear end of the pressurizing pump.

[0022] The above hydrogen production device may further include a second heat exchanger in front of the pressure swing adsorption device.

[0023] The above hydrogen production device may further include a mixer between the distributor and the combustor.

[0024] The above hydrogen production device may further include a re-liquefaction device that receives gaseous ammonia contained in the ship ammonia storage tank or the suction drum, re-liquefies it, and re-supplies it to the ship ammonia storage tank or the suction drum.

[0025] The above hydrogen production device can supply gaseous ammonia discharged from the second low-pressure heat recovery heat exchanger to the re-liquefaction device.

[0026] The above hydrogen production device may further include a fan at the rear end of the denitrification reactor.

[0027] According to another embodiment of the present invention, a vessel including the hydrogen production device is provided.

[0028] According to the present invention, high-purity hydrogen can be produced without generating carbon dioxide.

[0029] By combining the conventional ammonia vessel infrastructure with the hydrogen production device of the present invention, large quantities of hydrogen can be economically produced in a minimal area.

[0030] Figure 1 schematically illustrates a hydrogen production device of the present invention.

[0031] Figure 2 shows the adsorption selectivity of a pressure swing adsorption device by gas type.

[0032] Figure 3 shows the nitrogen oxide removal rate according to temperature in the denitrification reactor.

[0033] Figure 4 schematically illustrates a hydrogen production device according to one embodiment of the present invention.

[0034] Figure 5 is a graph showing the conversion rate of ammonia into nitrogen and hydrogen according to the temperature and pressure of the decomposition reactor.

[0035] Hereinafter, preferred embodiments of the present invention will be described. However, the embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0036] The present invention relates to a hydrogen production device that produces high-purity hydrogen using liquefied ammonia for ships.

[0037] Ammonia is 120 kg / m 3 As an ultra-high-capacity hydrogen storage and transporter with a storage capacity of , it can be stored at high pressure. Therefore, in the hydrogen production process using ammonia, a pressurization process is not required during the gas separation process, which reduces the energy consumption required for hydrogen production and increases energy efficiency. In addition, ammonia has a high liquefaction temperature, making it advantageous for long-distance transportation by storing it in liquid form.

[0038] Figure 1 is a schematic diagram illustrating a hydrogen production device according to one embodiment of the present invention. The present invention will now be described in more detail with reference to Figure 1.

[0039] Specifically, according to one aspect of the present invention, there is provided a shipboard ammonia storage tank (100); a tank pump (200) for pressurizing liquid ammonia inside the shipboard ammonia storage tank (100) and supplying it to a suction drum (300); a suction drum (300) for stabilizing the pressure of liquid ammonia supplied from the tank pump (200) and supplying it to a pressurizing pump (400); a pressurizing pump (400) for pressurizing and vaporizing liquid ammonia supplied from the suction drum (300) and supplying the produced gaseous ammonia to a distributor (500); and a distributor (500) for distributing and supplying gaseous ammonia supplied from the pressurizing pump (400) to a decomposition reactor (700), a combustor (600), and a denitrification reactor (900). A hydrogen production device is provided, comprising: a combustor (600) that combusts gaseous ammonia supplied from a distributor (500) to supply heat to a decomposition reactor (700); a decomposition reactor (700) that decomposes gaseous ammonia supplied from the distributor into hydrogen and nitrogen at 400 to 900°C in the presence of a catalyst; a pressure swing absorption (PSA) device (800) that receives off-gas discharged from the decomposition reactor (700) and separates hydrogen; and a denitrification reactor (900) that receives off-gas discharged from the combustor (600) and decomposes nitrogen oxide into nitrogen and water vapor.

[0040] The hydrogen production device of the present invention includes a ship ammonia storage tank (100).

[0041] The ammonia storage tank (100) for ships can store liquefied ammonia at a temperature of about -33°C and a pressure of about 1 barg.

[0042] The hydrogen production device of the present invention includes a tank pump (200) that pressurizes liquid ammonia inside a ship ammonia storage tank (100) and supplies it to a suction drum (300). In order to efficiently vaporize ammonia stored at low temperature, the tank pump (200) first pressurizes the ammonia to a tank pressure of 5 barg or more and supplies it to the suction drum (300).

[0043] The hydrogen production device of the present invention includes a suction drum (300) that stabilizes the pressure of liquid ammonia and supplies it to a pressurizing pump (400).

[0044] In order to stably increase the ultra-high pressure in the pressurizing pump (400), the ammonia supplied to the suction drum (300) is maintained in a liquid state.

[0045] The hydrogen production device of the present invention includes a pressurizing pump (400) that pressurizes and vaporizes liquid ammonia and supplies gaseous ammonia to a decomposition reactor (700) through a distributor (500).

[0046] Liquid ammonia discharged from the suction drum (300) is supplied to a pressure pump (400) and vaporized by being pressurized to 60 to 90 barg. The reaction equation for the ammonia vaporization reaction occurring in the pressure pump (400) is shown in Equation 1.

[0047] [Formula 1]

[0048] NH3(l) → NH3(g) (ΔH=+46.5kJ / mol)

[0049] The hydrogen production device of the present invention includes a distributor (500) that distributes and supplies gaseous ammonia supplied from a pressure pump (400) to a decomposition reactor (700) and a combustor (600).

[0050] The hydrogen production device of the present invention includes a combustor (600) that combusts gaseous ammonia supplied from the distributor (500) to supply heat to a decomposition reactor (700).

[0051] The reaction equation for the combustion reaction of ammonia occurring in the combustor (600) is shown in Equation 2 below.

[0052] [Formula 2]

[0053] 4NH3+ 3O2→ 2N2+ 6H2O (ΔH=-317kJ / mol)

[0054] When the hydrogen production device includes a mixer, the mixed gas supplied to the combustor (600) contains hydrogen. The combustion reaction of hydrogen is shown in Equation 3 below.

[0055] [Formula 3]

[0056] 2H2+ O2→ 2H2O (ΔH=-286kJ / mol)

[0057] Since the combustor (600) of the present invention combusts ammonia and hydrogen, which are carbon-free raw materials, carbon dioxide is not generated in the combustor (600) of the present invention.

[0058] Since the combustion reaction of the above ammonia and hydrogen is an exothermic reaction, the heat emitted can be used as a heat source for the ammonia decomposition reaction.

[0059] The hydrogen production device of the present invention includes a decomposition reactor (700) that decomposes gaseous ammonia supplied from the distributor (500) into hydrogen and nitrogen at a temperature of 400 to 900°C, specifically 700 to 900°C, in the presence of a catalyst. In the decomposition reactor (700), an ammonia decomposition reaction according to the following equation 4 proceeds.

[0060] [Formula 4]

[0061] 2NH3→ N2+ 3H2 (ΔH=+46kJ / mol)

[0062] At this time, since the ammonia decomposition reaction is an endothermic reaction, supply of reaction heat is required.

[0063] It is preferable that the conversion rate of the ammonia decomposition reaction occurring in the decomposition reactor (700) be 80% or more.

[0064] If the temperature of the decomposition reactor (700) is maintained at 700°C or higher, hydrogen production is possible through an ammonia decomposition reaction with a conversion rate of 80% or higher at 60 barg to 90 barg.

[0065] The off-gas discharged from the decomposition reactor (700) contains nitrogen, hydrogen, and un-decomposed ammonia.

[0066] The hydrogen production device of the present invention includes a pressure swing absorption (PSA) device that receives off-gas discharged from a decomposition reactor (700) and separates hydrogen.

[0067] The pressure swing adsorption device (800) above separates a mixed gas by utilizing the difference in adsorption selectivity of the adsorbate to the adsorbent. The adsorption step for separating weakly adsorbed components and strongly adsorbed components is usually performed at high pressure, and the device operates by lowering the pressure of the adsorption tower to desorb the adsorbed components and regenerate the adsorbent. The pressure swing adsorption device (800) is composed of two or more adsorption towers. For example, when composed of two adsorption towers, these adsorption towers are operated by periodically replacing each other. The inside of the adsorption tower is filled with an adsorbent, and ammonia and nitrogen are adsorbed and separated from purified compressed air supplied from an air buffer tank to continuously produce high-concentration oxygen. While the first adsorption tower, which periodically adsorbs ammonia and nitrogen, is regenerated by desorbing residual ammonia and residual nitrogen, the second adsorption tower continues to produce high-concentration oxygen through the same adsorption process.

[0068] The pressure swing adsorption device (800) may include two or more types of adsorbents. In this case, a mixed adsorbent comprising two or more types of adsorbents may be used in one adsorption tower. Alternatively, different types of adsorbents may be used in each of two or more adsorption towers.

[0069] The hydrogen production device of the present invention may include two or more of the above pressure swing adsorption devices. In this case, the two or more pressure swing adsorption devices may be expressed as a first pressure swing adsorption device, a second pressure swing adsorption device, etc.

[0070] According to one embodiment of the present invention, a hydrogen production device may include a first pressure swing adsorption device that receives off-gas discharged from a decomposition reactor (700) and adsorbs ammonia; and a second pressure swing adsorption device that receives off-gas discharged from the first pressure swing adsorption device and adsorbs nitrogen. In this case, the first pressure swing adsorption device may use an adsorbent having high adsorption selectivity for ammonia as an adsorbate, thereby adsorbing ammonia with high efficiency. Similarly, the second pressure swing adsorption device may use an adsorbent having high adsorption selectivity for nitrogen as an adsorbate, thereby adsorbing nitrogen with high efficiency. Alternatively, the first pressure swing adsorption device and the second pressure swing adsorption device may use a mixed adsorbent that mixes two or more types of adsorbents. In this case, the first pressure swing adsorption device and the second pressure swing adsorption device may use the same mixed adsorbent.

[0071] The adsorbent may be at least one selected from the group consisting of, for example, Carbon Molecular Sieve (CMS), Zeolite, Metal-organic frameworks (MOFs), Covalent organic frameworks (COFs), activated carbon, alumina, silica, etc.

[0072] When the hydrogen production device includes a first pressure swing adsorption device and a second pressure swing adsorption device, a purge gas supply line may be further included to supply off-gas discharged from the second pressure swing adsorption device as purge gas to the first pressure swing adsorption device. In this case, the hydrogen recovery rate can be increased.

[0073] Hydrogen and off-gas are discharged from the pressure swing adsorption device (800). The off-gas discharged from the pressure swing adsorption device (800) includes ammonia, nitrogen, and unseparated hydrogen. The hydrogen discharged from the pressure swing adsorption device (800) is mixed into the land pipeline network. The off-gas discharged from the pressure swing adsorption device (800) can be supplied to the first low-pressure heat recovery heat exchanger (1001) or a mixer.

[0074] Figure 2 shows the adsorption selectivity of the pressure swing adsorption device by gas type, and the hydrogen production can be maximized by utilizing the adsorption selectivity.

[0075] The hydrogen production device of the present invention includes a denitrification reactor (900) that receives off-gas discharged from the combustor (600) and decomposes nitrogen oxides into nitrogen and water vapor. More specifically, the denitrification reactor (900) decomposes nitrogen oxides contained in the off-gas discharged from the combustor (600) into nitrogen and water vapor in the presence of a reducing agent and a catalyst through a selective catalytic reduction (SCR) reaction. The reducing agent of the denitrification reactor (900) may be ammonia or urea water.

[0076] The above distributor (500) distributes and supplies gaseous ammonia supplied from the pressurized pump (400) to a decomposition reactor (700), a combustor (600), and a denitrification reactor (900), and the denitrification reactor (900) can use the gaseous ammonia supplied from the distributor (500) as a reducing agent.

[0077] The reaction formulas for the nitrogen oxide removal reaction occurring in the denitrification reactor (900) are shown in Equations 5 and 6 below. 90 to 95 mol% of the nitrogen oxide removed in the denitrification reactor (900) may be NO, and 5 to 10 mol% may be NO2.

[0078] [Formula 5]

[0079] 2NO + 2NH3+ 0.5O2-> 2N2+ 3H2O

[0080] [Formula 6]

[0081] 2NO2+ 4NH3+ O2-> 3N2+ 6H2O

[0082] The nitrogen oxide removal rate of the denitrification reactor (900) according to temperature is shown in FIG. 3. According to FIG. 3, it can be confirmed that the denitrification reactor (900) has a high nitrogen oxide removal efficiency when the operating temperature is 250°C to 450°C, specifically, when it is 350°C (about 662°F) to 450°C (about 842°F). Therefore, the appropriate operating temperature of the denitrification reactor (900) may be about 250°C to 450°C, or 350°C to 450°C.

[0083] When the hydrogen production device of the present invention includes a first low-pressure heat recovery heat exchanger (1001), off-gas of 250°C to 450°C, or 350°C to 450°C, can be supplied to the denitrification reactor (900).

[0084] Figure 4 is a schematic diagram illustrating a hydrogen production device according to one embodiment of the present invention. The present invention will now be described in further detail with reference to Figure 4.

[0085] The hydrogen production device of the present invention may further include a first low-pressure heat recovery heat exchanger (1001) at the front end of the combustor (600). When the first low-pressure heat recovery heat exchanger (1001) is included, combustion stability can be secured by heating gaseous ammonia supplied to the combustor (600).

[0086] The first low-pressure heat recovery heat exchanger (1001) can receive off-gas from the pressure swing adsorption device (800) and gaseous ammonia from the suction drum (300). Alternatively, it can receive gaseous ammonia from the second low-pressure heat recovery heat exchanger (1002). The first low-pressure heat recovery heat exchanger (1001) can lower the temperature of the off-gas supplied from the pressure swing adsorption device (800) and raise the temperature of the gaseous ammonia supplied from the suction drum (300).

[0087] Gaseous ammonia discharged from the first low-pressure heat recovery heat exchanger (1001) is supplied to the combustor (600).

[0088] The hydrogen production device of the present invention may further include a second low-pressure heat recovery heat exchanger (1002) at the rear end of the denitrification reactor (900). When the second low-pressure heat recovery heat exchanger (1002) is included, the temperature of the exhaust gas discharged from the denitrification reactor (900) can be lowered and stably discharged to the outside.

[0089] The second low-pressure heat recovery heat exchanger (1002) can receive exhaust gas from the denitrification reactor (900) and gaseous ammonia from the suction drum (300).

[0090] The exhaust gas discharged from the denitrification reactor (900) can be supplied to the second low-pressure heat recovery heat exchanger (1002) when the power source of the hydrogen production device and the heat capacity of the decomposition reactor (700) are insufficient. When the nitrogen oxide content of the exhaust gas discharged from the denitrification reactor (900) is below the environmental standard, low-temperature gaseous ammonia of about -33°C can be supplied from the suction drum (300) to the second low-pressure heat recovery heat exchanger (1002) to heat-exchange the exhaust gas, and then it can be stably discharged into the atmosphere.

[0091] The hydrogen production device of the present invention may further include a high-pressure heat recovery heat exchanger (1003) in front of the decomposition reactor (700). When the high-pressure heat recovery heat exchanger (1003) is included, the temperature of gaseous ammonia supplied to the decomposition reactor (700) can be increased.

[0092] The high-pressure heat recovery heat exchanger (1003) may receive gaseous ammonia from the pressurizing pump (400) and off-gas from the decomposition reactor (700). Alternatively, the high-pressure heat recovery heat exchanger (1003) may receive gaseous ammonia from the first heat exchanger (1004). The temperature of the gaseous ammonia may be increased by heat-exchanging low-temperature gaseous ammonia with high-temperature off-gas. Gaseous ammonia discharged from the high-pressure heat recovery heat exchanger (1003) may be supplied to the decomposition reactor (700), and the off-gas may be supplied to the pressure swing adsorption device (800). Alternatively, the off-gas may be supplied to the second heat exchanger (1005).

[0093] The hydrogen production device of the present invention may further include a first heat exchanger (1004) at the rear end of the pressurizing pump (400).

[0094] The ammonia vaporization reaction occurring in the pressurizing pump (400) is an endothermic reaction. Therefore, the gaseous ammonia discharged from the pressurizing pump (400) has a low temperature. In the first heat exchanger (1004), a ship-specific heating utility can be applied to increase the temperature of the gaseous ammonia supplied from the pressurizing pump (400). The gaseous ammonia discharged from the first heat exchanger (1004) can be supplied to the distributor (500). Alternatively, the gaseous ammonia discharged from the first heat exchanger (1004) can be supplied to the high-pressure heat recovery heat exchanger (1003).

[0095] The hydrogen production device of the present invention may further include a second heat exchanger (1005) in front of the pressure swing adsorption device (800).

[0096] The second heat exchanger (1005) can be supplied with the off-gas discharged from the decomposition reactor (700). Alternatively, the second heat exchanger (1005) can be supplied with the off-gas discharged from the high-pressure heat recovery heat exchanger (1003). The second heat exchanger (1005) can apply a cooling utility for ships to lower the temperature of the off-gas supplied to the pressure swing adsorption device (800). Alternatively, the second heat exchanger (1005) can lower the temperature of the off-gas using glycol or seawater. The off-gas discharged from the second heat exchanger (1005) is supplied to the pressure swing adsorption device (800).

[0097] The hydrogen production device of the present invention may further include a mixer between the distributor (500) and the combustor (600). The mixer receives gaseous ammonia from the distributor (500) and off-gas discharged from the pressure swing adsorption device (800), mixes the gaseous ammonia and off-gas, and then injects the mixture into the combustor (600).

[0098] When the hydrogen production device includes a first pressure swing adsorption device and a second pressure swing adsorption device, the mixer can be supplied with off-gas discharged from the second pressure swing adsorption device.

[0099] The hydrogen production device of the present invention may further include a reliquefaction device (1100) that receives gaseous ammonia contained in a ship ammonia storage tank (100) or a suction drum (300), reliquefies it, and re-supplies it to the ship ammonia storage tank (100) or the suction drum (300).

[0100] When the pressure of a marine ammonia storage tank (100) or a suction drum (300) is lowered, ammonia may vaporize. If the vaporized ammonia increases, the pressure of the marine ammonia storage tank (100) or the suction drum (300) may abnormally increase. In this case, the gaseous ammonia contained in the marine ammonia storage tank (100) or the suction drum (300) may be supplied to a reliquefaction device (1100) to stably maintain the pressure inside the marine ammonia storage tank (100) or the suction drum (300).

[0101] The hydrogen production device of the present invention may further include a fan (1200).

[0102] Off-gas discharged from the denitrification reactor (900) can be discharged to the outside through a fan (1200). If the pressure of the off-gas discharged from the denitrification reactor (900) is low and it is difficult to discharge it into the atmosphere, the pressure can be increased with a fan (1200) to stably discharge the off-gas into the atmosphere.

[0103] Experimental example

[0104] At each temperature of 650℃ and 700℃, the decomposition reactor was operated while changing the pressure to carry out the ammonia decomposition reaction, and the conversion rate of ammonia into nitrogen and hydrogen was calculated, and the results are shown in Fig. 5.

[0105] At a temperature of 700°C, the decomposition reactor was operated at pressures of 10 barg, 20 barg, 30 barg, 40 barg, 50 barg, 60 barg, 70 barg, 80 barg, and 90 barg, respectively. A low-cost catalyst containing 30 to 60 wt% of nickel was used as the reaction catalyst.

[0106] Even at a temperature of 650°C, the decomposition reactor was operated at pressures of 10 barg, 20 barg, 30 barg, 40 barg, 50 barg, 60 barg, 70 barg, 80 barg and 90 barg, using the same reaction catalyst.

[0107] Referring to Fig. 5, it was confirmed that when the operating temperature of the decomposition reactor is 700°C or higher, a conversion rate of 80% or higher can be achieved even at a high pressure of 60 barg to 90 barg.

[0108] Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be apparent to those skilled in the art that various modifications and variations are possible within a scope that does not depart from the technical spirit of the present invention described in the claims.

[0109] [Explanation of symbols]

[0110] 100: ammonia storage tank for ships, 200: tank pump, 300: suction drum, 400: pressurizing pump, 500: distributor, 600: combustor, 700: decomposition reactor, 800: pressure swing adsorption device, 900: denitrification reactor, 1001: first low-pressure heat recovery heat exchanger, 1002: second low-pressure heat recovery heat exchanger, 1003: high-pressure heat recovery heat exchanger, 1004: first heat exchanger, 1005: second heat exchanger, 1100: reliquefaction device, 1200: fan

Claims

1. Ammonia storage tank for ships; A tank pump for pressurizing liquid ammonia inside the ammonia storage tank for the above ship and supplying it to the suction drum; A suction drum for stabilizing the pressure of liquid ammonia supplied from the above tank pump and supplying it to the pressurizing pump; A pressurizing pump that pressurizes and vaporizes liquid ammonia supplied from the suction drum and supplies the produced gaseous ammonia to a distributor; A distributor that distributes and supplies gaseous ammonia supplied from the above pressurized pump to a decomposition reactor and a combustor; A combustor that combusts gaseous ammonia supplied from the above distributor to supply heat to a decomposition reactor; A decomposition reactor which decomposes gaseous ammonia supplied from the distributor into hydrogen and nitrogen at a temperature of 400 to 900°C in the presence of a catalyst; A pressure swing absorption (PSA) device that receives off-gas discharged from the above decomposition reactor and separates hydrogen; and A hydrogen production device, comprising a denitrification reactor that receives off-gas discharged from the above-mentioned combustor and decomposes nitrogen oxides into nitrogen and water vapor.

2. In paragraph 1, A hydrogen production device having a conversion rate of 80% or higher in the ammonia decomposition reaction that occurs in the decomposition reactor.

3. In paragraph 1, A hydrogen production device comprising two or more of the above pressure swing adsorption devices.

4. In paragraph 3, A first pressure swing adsorption device that receives off-gas discharged from the above decomposition reactor and adsorbs ammonia; and A second pressure swing adsorption device that receives the off-gas discharged from the first pressure swing adsorption device and adsorbs nitrogen; A hydrogen production device comprising:

5. In paragraph 4, A hydrogen production device further comprising a purge gas supply line for supplying off-gas discharged from a second pressure swing adsorption device as purge gas to a first pressure swing adsorption device.

6. In paragraph 1, The above distributor distributes and supplies gaseous ammonia supplied from the pressurized pump to the decomposition reactor, the combustion reactor, and the denitrification reactor. The above denitrification reactor is a hydrogen production device that uses gaseous ammonia supplied from the distributor as a reducing agent.

7. In paragraph 1, A hydrogen production device further comprising a first low-pressure heat recovery heat exchanger in the combustion chamber.

8. In paragraph 1, A hydrogen production device further comprising a second low-pressure heat recovery heat exchanger located at the rear end of the above denitrification reactor.

9. In paragraph 1, A hydrogen production device further comprising a high pressure heat recovery heat exchanger in front of the decomposition reactor.

10. In paragraph 1, A hydrogen production device further comprising a first heat exchanger at a rear end of the pressurizing pump.

11. In paragraph 1, A hydrogen production device further comprising a second heat exchanger in front of the pressure swing adsorption device.

12. In paragraph 1, A hydrogen production device further comprising a mixer between the distributor and the combustor.

13. In paragraph 1, A hydrogen production device further comprising a re-liquefaction device that receives gaseous ammonia contained in the ammonia storage tank for ships or the suction drum, re-liquefies it, and re-supplies it to the ammonia storage tank for ships or the suction drum.

14. In paragraph 13, A hydrogen production device that supplies gaseous ammonia discharged from a second low-pressure heat recovery heat exchanger to a re-liquefaction device.

15. In paragraph 1, A hydrogen production device further comprising a fan at the rear end of the above denitrification reactor.

16. A vessel comprising a hydrogen production device according to any one of clauses 1 to 15.

Images