Ammonia decomposition device

Abstract

To provide an ammonia decomposing apparatus capable of suppressing nitriding of piping for supplying ammonia to a reactor in which ammonia is decomposed.SOLUTION: The ammonia decomposing apparatus comprises a reactor filled with a catalyst for a decomposition reaction for decomposing ammonia as a raw material into hydrogen and nitrogen, a burner provided in the reactor on the upstream side from the catalyst for burning hydrogen, and an ammonia supply line for supplying ammonia into the reactor on the upstream side from the catalyst.SELECTED DRAWING: Figure 1

Description

【Technical Field】 【0001】 This disclosure relates to an ammonia decomposition apparatus. 【Background Art】 【0002】 Patent Document 1 describes an ammonia decomposition apparatus that decomposes ammonia into hydrogen and nitrogen. In this ammonia decomposition apparatus, a burner for burning ammonia is provided upstream of the catalyst in a reactor filled with a catalyst for the ammonia decomposition reaction. The combustion heat of ammonia by the burner can be used as heat for causing the decomposition reaction of ammonia, which is an endothermic reaction. 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Translation of PCT International Publication No. 2020-531388 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 However, in order to stably burn ammonia with a burner, it is necessary to raise the temperature of ammonia before it is supplied to the burner. Then, since high-temperature ammonia flows through the piping for supplying ammonia to the burner, there is a risk that ammonia reacts with the metal material of the piping, causing the metal material to nitride, resulting in a decrease in mechanical strength and ultimately pipe breakage. 【0005】 In view of the above circumstances, at least one embodiment of this disclosure aims to provide an ammonia decomposition apparatus that can suppress the nitriding of the piping for supplying ammonia to a reactor in which ammonia decomposition is carried out. 【Means for Solving the Problems】 【0006】 To achieve the above objective, the ammonia decomposition apparatus according to this disclosure comprises a reactor filled with a catalyst for a decomposition reaction that decomposes ammonia, which is a raw material, into hydrogen and nitrogen; a burner provided in the reactor upstream of the catalyst for burning hydrogen; and an ammonia supply line for supplying ammonia into the reactor upstream of the catalyst. 【0007】 Furthermore, another ammonia decomposition apparatus according to this disclosure comprises: a reactor filled with a catalyst for a decomposition reaction that decomposes ammonia, which is a raw material, into hydrogen and nitrogen; a burner provided in the reactor upstream of the catalyst for burning a portion of the ammonia raw material; an ammonia supply line for supplying ammonia-containing gas, which includes the ammonia raw material, to the burner; an outlet gas line through which the outlet gas, which includes hydrogen and nitrogen produced by the decomposition of ammonia in the reactor, flows after it has flowed out of the reactor; a heater for heating the ammonia-containing gas flowing through the ammonia supply line, the first heater which exchanges heat between the ammonia-containing gas and the outlet gas flowing through the outlet gas line; and a hydrogen supply line upstream of the first heater which supplies hydrogen-containing gas, which includes hydrogen, to the ammonia-containing gas flowing through the ammonia supply line. [Effects of the Invention] 【0008】 According to the ammonia decomposition apparatus of this disclosure, by using the heat of combustion of hydrogen by the burner as heat to cause the ammonia decomposition reaction, which is an endothermic reaction, it becomes unnecessary to raise the temperature of the ammonia flowing through the ammonia supply line, or the degree of temperature rise of the ammonia can be suppressed, thereby preventing the ammonia supply line from nitriding due to the reaction between the high-temperature ammonia flowing through the ammonia supply line and the metal material of the ammonia supply line. 【0009】 In another ammonia decomposition apparatus of this disclosure, the ammonia-containing gas is heated in a first heater installed in the ammonia supply line for supplying ammonia-containing gas to the burner. Therefore, downstream of the first heater, there is a risk that the ammonia will react with the metal material of the ammonia supply line and cause nitridation of the ammonia supply line. However, by supplying a hydrogen-containing gas to the ammonia-containing gas upstream of the first heater, the concentration of ammonia in the ammonia-containing gas is reduced, thereby suppressing nitridation of the ammonia supply line downstream of the first heater. [Brief explanation of the drawing] 【0010】 [Figure 1] A schematic diagram of the configuration of an ammonia decomposition apparatus according to Embodiment 1 of this disclosure. [Figure 2] A schematic diagram of a modified configuration of the ammonia decomposition apparatus according to Embodiment 1 of this disclosure. [Figure 3] A schematic diagram of another modified configuration of the ammonia decomposition apparatus according to Embodiment 1 of this disclosure. [Figure 4] This is a schematic diagram of yet another modified configuration of the ammonia decomposition apparatus according to Embodiment 1 of this disclosure. [Figure 5] This is a schematic diagram of the configuration of an ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 6] A schematic diagram of a modified configuration of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 7] A schematic diagram illustrating another modified configuration of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 8] This is a schematic diagram of the reactor configuration of yet another modified example of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 9] This is a schematic diagram of the reactor configuration of yet another modified example of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 10] This is a schematic diagram of the reactor configuration of yet another modified example of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure. [Figure 11]It is a perspective view of a piping member provided in the reactor shown in FIG. 10. [Figure 12] It is a schematic configuration diagram of a reactor of yet another modified example of the ammonia decomposition apparatus according to Embodiment 2 of the present disclosure. 【MODE FOR CARRYING OUT THE INVENTION】 【0011】 Hereinafter, the ammonia decomposition apparatus according to the embodiment of the present disclosure will be described based on the drawings. The embodiments described below show one aspect of the present disclosure, do not limit this disclosure, and can be arbitrarily changed within the scope of the technical idea of the present disclosure. 【0012】 (Embodiment 1) <Configuration of the ammonia decomposition apparatus according to Embodiment 1 of the present disclosure> As shown in FIG. 1, the ammonia decomposition apparatus 1 according to Embodiment 1 of the present disclosure is an apparatus that decomposes ammonia, which is a raw material, into hydrogen and nitrogen by the reaction represented by the following reaction formula (1). The ammonia decomposition apparatus 1 includes a reactor 2 filled with a catalyst 3 for the decomposition reaction of ammonia represented by the reaction formula (1). 2NH3→N2+3H2···(1) 【0013】 In the reactor 2, an upstream space 2a and a downstream space 2b are respectively formed on the upstream side and the downstream side of the catalyst 3. A burner 4 for burning hydrogen is provided in the reactor 2 on the upstream side of the catalyst 3. An ammonia supply line 5 for supplying an ammonia-containing gas containing ammonia to the upstream space 2a, that is, to the upstream side of the catalyst, is connected to the reactor 2. A hydrogen supply line 6 for supplying a hydrogen-containing gas (specific examples will be described later) containing hydrogen to the burner 4 and an oxygen supply line 7 for supplying an oxygen-containing gas (for example, air) containing oxygen to the burner 4 are connected to the burner 4. 【0014】 Reactor 2 is connected to an outlet gas line 8 through which the outlet gas discharged from reactor 2 flows, with one end communicating with the downstream space 2b. According to reaction equation (1), the outlet gas contains nitrogen and hydrogen. Therefore, the other end of the outlet gas line 8 is connected to a consumption / storage facility 10 for consuming or storing the outlet gas containing nitrogen and hydrogen. The outlet gas may also contain unreacted ammonia. For this reason, an ammonia recovery device 9 may be provided in the outlet gas line 8 to remove ammonia from the outlet gas. A recovered ammonia line 14 may be provided connecting the ammonia recovery device 9 and the ammonia supply line 5 to return the ammonia removed from the outlet gas by the ammonia recovery device 9 to the ammonia supply line 5. The configuration of the ammonia recovery device 9 is not particularly limited and may include, for example, a water scrubber or a pressure fluctuation adsorption (PSA) device. Note that if the ammonia decomposition rate in reactor 2 is high and there is little unreacted ammonia in the outlet gas, the ammonia recovery device 9 may not be provided. 【0015】 The hydrogen supply line 6 can be configured to be connected to a hydrogen storage facility or hydrogen production device located inside or outside the ammonia decomposition unit 1, and to supply hydrogen-containing gas from there, or it can be configured to branch off from the outlet gas line 8. In the latter configuration, the hydrogen supply line 6 is provided with a compressor 11 for pressurizing the outlet gas, i.e., the hydrogen-containing gas. If an ammonia recovery device 9 is provided in the outlet gas line 8, the hydrogen supply line 6 may be configured to branch off from the outlet gas line 8 downstream of the ammonia recovery device 9, or it may be configured to branch off from the outlet gas line 8 upstream of the ammonia recovery device 9. 【0016】 A first heat exchanger 12 for heating the hydrogen-containing gas may be provided in the hydrogen supply line 6 (when a compressor 11 is provided in the hydrogen supply line 6, on the downstream side of the compressor 11). In order for the hydrogen-containing gas in the first heat exchanger 12 to be heated by exchanging heat with the effluent gas flowing out from the reactor 2, the effluent gas line 8 is configured to pass through the first heat exchanger 12. Further, a second heat exchanger 13 for heating the ammonia-containing gas may be provided in the ammonia supply line 5. In order for the ammonia-containing gas in the second heat exchanger 13 to be heated by exchanging heat with the effluent gas after exchanging heat with the hydrogen-containing gas in the first heat exchanger 12, the effluent gas line 8 is configured to pass through the second heat exchanger 13. 【0017】 When an ammonia recovery device 9 is provided in the ammonia decomposition device 1, in order for the ammonia removed from the effluent gas by the ammonia recovery device 9 to be heated by the second heat exchanger 13 as well, it is preferable to configure the recovered ammonia line 14 to be connected to the ammonia supply line 5 upstream of the second heat exchanger 13. 【0018】 Although not an essential configuration, the inner surface 2c of the reactor 2 may be covered with a refractory 2d. When the refractory 2d is provided, the catalyst 3 is filled on the side opposite to the inner surface 2c with respect to the refractory 2d. As the refractory 2d, for example, bricks, refractory bricks, refractory cement, etc. can be used. 【0019】 <Operation of the ammonia decomposition device according to Embodiment 1 of the present disclosure> Next, the operation of the ammonia decomposition device 1 according to Embodiment 1 of the present disclosure will be described. The ammonia-containing gas flows into the upstream space 2a in the reactor 2 through the ammonia supply line 5. Further, a hydrogen-containing gas is supplied to the burner 4 through the hydrogen supply line 6, and an oxygen-containing gas is supplied to the burner 4 through the oxygen supply line 7, and hydrogen is burned in the burner 4. Combustion gas containing the heat of combustion due to the combustion of hydrogen is discharged from the burner 4 into the upstream space 2a, and the ammonia-containing gas is heated by mixing the ammonia-containing gas and the combustion gas in the upstream space 2a. 【0020】 Since the ammonia-containing gas is heated by the combustion gas of hydrogen, it is not necessarily required to heat the ammonia-containing gas to the temperature required for the ammonia decomposition reaction when it flows through the ammonia supply line 5, or to supply ammonia-containing gas heated to that temperature to the upstream space 2a via the ammonia supply line 5. For this reason, the temperature of the ammonia-containing gas flowing through the ammonia supply line 5 can be kept below the temperature at which ammonia reacts with the metal material of the ammonia supply line, thereby suppressing nitridation of the ammonia supply line 5. In addition, since it is hydrogen that is burned in the burner 4, and ammonia is not directly burned in the burner 4, the generation of nitrogen oxides (NOx) can also be suppressed. 【0021】 The mixed gas of ammonia-containing gas heated in the upstream space 2a and combustion exhaust gas passes through catalyst 3. As the mixed gas passes through catalyst 3, at least a portion of the ammonia in the mixed gas is decomposed into hydrogen and nitrogen by the catalytic action of catalyst 3, which causes the ammonia decomposition reaction shown in reaction equation (1). The resulting effluent gas, containing hydrogen, nitrogen, and unreacted ammonia, flows out from the downstream space 2b and circulates through the effluent gas line 8. If the amount of unreacted ammonia in the effluent gas is small, the effluent gas flowing out from the downstream space 2b is supplied to the consumption / storage facility 10 via the effluent gas line 8. 【0022】 In this way, by using the heat of combustion of hydrogen by the burner 4 as heat to cause the endothermic reaction of ammonia decomposition, it becomes unnecessary to raise the temperature of the ammonia-containing gas flowing through the ammonia supply line 5, or the degree of temperature rise of the ammonia can be suppressed. This suppresses the reaction between the high-temperature ammonia flowing through the ammonia supply line 5 and the metal material of the ammonia supply line 5, which causes nitriding of the ammonia supply line 5. 【0023】 When the ammonia decomposition unit 1 is equipped with a first heat exchanger 12 and a second heat exchanger 13, the hydrogen-containing gas flowing through the hydrogen supply line 6 is heated in the first heat exchanger 12 by heat exchange with the effluent gas flowing out of the reactor 2 and then supplied to the burner 4. In addition, the ammonia-containing gas flowing through the ammonia supply line 5 is heated in the second heat exchanger 13 by heat exchange with the effluent gas that has already exchanged heat with the hydrogen-containing gas in the first heat exchanger 12 and then flows into the upstream space 2a. By providing the ammonia decomposition unit 1 with a first heat exchanger 12 and a second heat exchanger 13, the temperature of the ammonia-containing gas and hydrogen-containing gas can be increased, thereby improving the amount of heat recovered in the ammonia decomposition unit. 【0024】 On the other hand, if the effluent gas that has just flowed out of reactor 2 and the ammonia-containing gas exchange heat, the temperature of the effluent gas may become too high, causing the temperature of the ammonia-containing gas to rise too high and potentially nitriding the ammonia supply line 5. In contrast, in a configuration in the ammonia decomposition unit 1 that includes a first heat exchanger 12 and a second heat exchanger 13, the effluent gas flowing out of reactor 2 and the hydrogen-containing gas exchange heat, and the effluent gas, whose temperature has dropped below the temperature at which it flowed out of reactor 2, exchanges heat with the ammonia-containing gas. This raises the temperature of the ammonia-containing gas to a level that does not cause nitriding of the ammonia supply line 5, thus suppressing nitriding of the ammonia supply line 5. 【0025】 As described above, if the unreacted ammonia contained in the effluent gas cannot be ignored, an ammonia recovery device 9 can be installed in the effluent gas line 8 (downstream of the second heat exchanger 13 if a first heat exchanger 12 and a second heat exchanger 13 are installed). In this case, ammonia is recovered from the effluent gas in the ammonia recovery device 9, and the effluent gas, which now contains hydrogen, nitrogen, and trace amounts of unrecovered ammonia, is partially supplied to the burner 4 via the hydrogen supply line 6 as hydrogen-containing gas, and the remainder is supplied to the consumption / storage equipment 10. The recovered ammonia is supplied to the ammonia supply line 5 via the recovered ammonia line 14 and supplied to the reactor 2 as part of the raw material ammonia. This improves the ammonia decomposition rate. 【0026】 By configuring the hydrogen supply line 6 to branch off from the exhaust gas line 8, a portion of the exhaust gas can be supplied to the burner 4 as hydrogen-containing gas. This configuration eliminates the need to supply hydrogen from outside the ammonia decomposition unit 1, allowing the ammonia decomposition unit 1 to operate independently without relying on external equipment. Furthermore, as mentioned above, the exhaust gas contains not only hydrogen but also nitrogen. Since the combustion gas temperature of the burner 4, which burns hydrogen, is higher than that of a typical hydrocarbon burner, this can affect the design of the burner 4 body and its peripheral equipment. In contrast, by using nitrogen-containing exhaust gas as hydrogen-containing gas, the combustion gas temperature can be lowered compared to burning pure hydrogen, thereby mitigating such effects. 【0027】 When an ammonia recovery device 9 is installed in the outflow gas line 8, if the hydrogen supply line 6 is configured to branch off from the outflow gas line 8 downstream of the ammonia recovery device 9, as shown in Figure 1, the outflow gas after ammonia has been removed by the ammonia recovery device 9 is supplied to the burner 4 as hydrogen-containing gas, thereby suppressing the consumption of some of the unreacted ammonia by combustion in the burner 4. 【0028】 However, if the ammonia decomposition rate in reactor 2 is high and there is little unreacted ammonia in the effluent gas, the hydrogen supply line 6 can be configured to branch off from the effluent gas line 8 upstream of the ammonia recovery unit 9, as shown in Figure 2. In this configuration, a portion of the effluent gas can be supplied to the burner 4 as hydrogen-containing gas without pressure loss in the ammonia recovery unit 9 or heat loss due to cooling in the ammonia recovery unit 9, thus improving the overall energy efficiency of the ammonia decomposition unit 1. However, as long as this configuration is adopted, a hydrogen-containing gas with a higher ammonia concentration will be supplied to the burner 4 compared to the case where the hydrogen supply line 6 is branched off from the effluent gas line 8 downstream of the ammonia recovery unit 9, and NOx derived from ammonia may be generated due to the temperature of combustion in the burner 4. However, since at least a portion of the generated NOx can be converted into nitrogen and water by a reaction represented by, for example, the reaction shown in reaction equation (2) below, the impact on equipment downstream of reactor 2 can be reduced. 6NO2+8NH3→7N2+12H2O ···(2) 【0029】 <Modified example of ammonia decomposition apparatus according to Embodiment 1 of this disclosure> As shown in Figure 3, if the hydrogen-containing gas is part of the effluent gas, a nitrogen removal device 20 may be installed in the hydrogen supply line 6 to remove nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line 6. The configuration of the nitrogen removal device 20 is not particularly limited, but for example, a membrane separator including a separation membrane capable of separating hydrogen and nitrogen can be used. If a first heat exchanger 12 is provided in the hydrogen supply line 6, it is preferable to install the nitrogen removal device 20 upstream of the first heat exchanger 12, and it is preferable to install the nitrogen removal device 20 upstream of the compressor 11. Also, if the nitrogen removal device 20 is a membrane separator, it is undesirable for ammonia to be entrained in the nitrogen removal device 20, so it is preferable to install the nitrogen removal device 20 in the hydrogen supply line 6 that branches off from the effluent gas line 8 downstream of the ammonia recovery device 9. 【0030】 In the ammonia decomposition apparatus 1 with the configuration shown in Figure 3, nitrogen is separated from the hydrogen-containing gas in the nitrogen removal device 20 and purged out of the system. As a result, a hydrogen-containing gas with a higher hydrogen concentration is supplied to the burner 4 compared to the ammonia decomposition apparatus 1 with the configuration shown in Figure 1 or 2. As mentioned above, there is a problem that the temperature of the combustion gas increases as the hydrogen concentration in the hydrogen-containing gas increases, but by appropriately selecting the specifications of the burner 4 and appropriately designing the fire-resistant construction of the reactor 2, the nitrogen removal device 20 can be installed in the hydrogen supply line 6. By installing the nitrogen removal device 20, the volumetric flow rate of the hydrogen-containing gas supplied to the burner 4 can be reduced, so the size of the hydrogen supply line 6 and, if the compressor 11 that pressurizes the hydrogen-containing gas is installed in the hydrogen supply line 6, the size of the compressor 11 can be reduced, and as a result, the ammonia decomposition apparatus 1 can be made more compact. 【0031】 As shown in Figure 4, in addition to the configuration with a first heat exchanger 12 and a second heat exchanger 13, a third heat exchanger 30 may be further provided in which the oxygen-containing gas flowing through the oxygen supply line 7 and the outflow gas after heat exchange with the hydrogen-containing gas in the first heat exchanger 12 exchange heat may be further provided. In this configuration, the oxygen-containing gas is heated by heat exchange with the outflow gas in the third heat exchanger 30 and supplied to the burner 4. Furthermore, the outflow gas that exchanges heat with the ammonia-containing gas in the second heat exchanger 13 is the outflow gas that has undergone heat exchange with the hydrogen-containing gas in the first heat exchanger 12 and heat exchange with the oxygen-containing gas in the third heat exchanger 30. 【0032】 In this configuration, after heat exchange occurs between the effluent gas flowing out of reactor 2 and the hydrogen-containing gas, further heat exchange occurs between the effluent gas and the oxygen-containing gas. This allows the effluent gas, now at a temperature lower than when it flowed out of reactor 2, to exchange heat with the ammonia-containing gas. This raises the temperature of the ammonia-containing gas to a level that does not cause nitriding of the ammonia supply line 5, thus suppressing nitriding of the ammonia supply line 5. Furthermore, since the temperatures of both the ammonia-containing gas and the hydrogen-containing gas can be raised, the amount of heat recovered in the ammonia decomposition unit 1 can be improved. In addition, the increased heat recovery allows for a reduction in the amount of hydrogen and oxygen consumed in the combustion of burner 4, thus enabling a more compact configuration of the ammonia decomposition unit 1. 【0033】 (Embodiment 2) Next, an ammonia decomposition apparatus according to Embodiment 2 of this disclosure will be described. The ammonia decomposition apparatus according to Embodiment 2 has a modified configuration of the burner provided in the reactor 2 compared to Embodiment 1. In Embodiment 2, components that are the same as those in Embodiment 1 are given the same reference numerals, and their detailed descriptions are omitted. 【0034】 <Configuration of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure> As shown in Figure 5, in the reactor 2 of the ammonia decomposition apparatus 40 according to Embodiment 2 of this disclosure, a burner 44 is provided upstream of the catalyst 3 for burning a portion of the raw material ammonia. The burner 44 is connected to an ammonia supply line 5 through which ammonia-containing gas containing ammonia flows, and an oxygen supply line 7 for supplying oxygen-containing gas (e.g., air) containing oxygen to the burner 44. The ammonia supply line 5 is provided with a first heater 43 for heating the ammonia-containing gas. In the first heater 43, the ammonia-containing gas is heated by heat exchange with the effluent gas flowing out of the reactor 2, so that the effluent gas line 8 is configured to pass through the first heater 43. Upstream of the first heater 43, a hydrogen supply line 46 is provided to supply hydrogen-containing gas containing hydrogen to the ammonia-containing gas flowing through the ammonia supply line 5. 【0035】 The hydrogen supply line 46 can be connected to a hydrogen storage facility or hydrogen production device located inside or outside the ammonia decomposition unit 40, and configured to supply hydrogen-containing gas from there, or the hydrogen supply line 46 can be configured to branch off from the outlet gas line 8. If an ammonia recovery device 9 is provided in the outlet gas line 8, the hydrogen supply line 46 may be configured to branch off either upstream or downstream of the ammonia recovery device 9 (Figure 5 shows an exemplary configuration in which the hydrogen supply line 46 branches off upstream of the ammonia recovery device 9). In the configuration in which the hydrogen supply line 46 branches off from the outlet gas line 8, the hydrogen supply line 46 may be provided with a compressor 11 for pressurizing the outlet gas, which is hydrogen-containing gas. The configuration of the reactor 2 and the configuration of the ammonia recovery device 9 are the same as in Embodiment 1. 【0036】 <Operation of the ammonia decomposition apparatus according to Embodiment 2 of this disclosure> Next, the operation of the ammonia decomposition apparatus 40 according to Embodiment 2 of this disclosure will be described. Ammonia-containing gas is supplied to the burner 44 via the ammonia supply line 5, and oxygen-containing gas is supplied via the oxygen supply line 7, and a portion of the raw material ammonia is burned in the burner 44. In order to burn a portion of the ammonia in the ammonia-containing gas in the burner 44, the ammonia-containing gas is heated in the first heater 43 to a temperature suitable for combustion in the burner 44. However, if the temperature in the first heater 43 becomes too high, the metal material of the ammonia supply line 5 reacts with the ammonia between the first heater 43 and the burner 44, causing the ammonia supply line 5 to undergo nitridation. 【0037】 In contrast, in Embodiment 2, hydrogen-containing gas is supplied to the ammonia-containing gas flowing through the ammonia supply line 5 via the hydrogen supply line 46 before the ammonia-containing gas is heated in the first heater 43. This reduces the ammonia concentration in the ammonia-containing gas. Even when the ammonia-containing gas, whose ammonia concentration has been reduced by the supply of hydrogen-containing gas, is heated to a high temperature in the first heater 43, the reaction between the metal material in the ammonia supply line 5 and the ammonia becomes less likely compared to the case where the ammonia-containing gas is not supplied with hydrogen-containing gas. This suppresses nitriding of the ammonia supply line 5. 【0038】 In the burner 44, the ammonia-containing gas is heated by the combustion heat generated when a portion of the ammonia is burned, and the heated ammonia-containing gas and the combustion gas of ammonia flow into the upstream space 2a. The mixed gas of the ammonia-containing gas and the combustion exhaust gas in the upstream space 2a passes through the catalyst 3 in the same manner as in Embodiment 1, becomes the outflow gas, flows out from the downstream space 2b, and circulates through the outflow gas line 8. The outflow gas circulating in the outflow gas line 8 exchanges heat with the ammonia-containing gas in the first heater 43, heating the ammonia-containing gas while cooling the outflow gas. If the amount of unreacted ammonia contained in the outflow gas is small, the cooled outflow gas in the first heater 43 is supplied to the consumption / storage facility 10 via the outflow gas line 8. If the amount of unreacted ammonia contained in the outflow gas is significant and an ammonia recovery device 9 is provided, ammonia is recovered from the outflow gas in the ammonia recovery device 9 before being supplied to the consumption / storage facility 10. 【0039】 In this way, by supplying hydrogen-containing gas to the ammonia-containing gas upstream of the first heater 43, the concentration of ammonia in the ammonia-containing gas decreases, thereby suppressing nitridation of the ammonia supply line 5 downstream of the first heater 43. 【0040】 Furthermore, similar to Embodiment 1, by configuring the hydrogen supply line 46 to branch off from the outlet gas line 8, a portion of the outlet gas can be supplied to the burner 44 as hydrogen-containing gas. With this configuration, there is no need to supply hydrogen from outside the ammonia decomposition unit 40, so the ammonia decomposition unit 40 can be operated independently without relying on external equipment. 【0041】 When a water-washing type device is used as the ammonia recovery device 9, from the viewpoint of thermal efficiency, it is preferable to recover as much heat as possible from the effluent gas before it flows into the ammonia recovery device 9. In contrast, in Embodiment 2, the effluent gas is cooled by heat exchange with the ammonia-containing gas in the first heater 43 before it flows into the ammonia recovery device 9, thereby reducing the amount of heat released from the effluent gas in the ammonia recovery device 9 (corresponding to heat loss), and thus suppressing the deterioration of the thermal efficiency of the ammonia decomposition device 40. 【0042】 <Modified example of ammonia decomposition apparatus according to Embodiment 2 of this disclosure> As shown in Figure 6, if hydrogen-containing gas is part of the outflow gas, a nitrogen removal device 20 may be installed in the hydrogen supply line 46 to remove nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line 46. The configuration of the nitrogen removal device 20 is the same as in Embodiment 1. By installing the nitrogen removal device 20 in the hydrogen supply line 46, the volumetric flow rate of hydrogen-containing gas supplied to the ammonia-containing gas flowing through the ammonia supply line 5 can be reduced, thereby reducing the size of the hydrogen supply line 46 and the ammonia supply line 5, and as a result, the ammonia decomposition device 40 can be made more compact. 【0043】 As shown in Figure 7, a second heater 45 may be provided in which the oxygen-containing gas flowing through the oxygen supply line 7 and the effluent gas flowing out of the reactor 2 exchange heat. In this configuration, the oxygen-containing gas is heated by heat exchange with the effluent gas in the second heater 45 and supplied to the burner 44. Furthermore, the effluent gas that exchanges heat with the ammonia-containing gas in the first heater 43 is the effluent gas that has undergone heat exchange with the oxygen-containing gas in the second heater 45. In this configuration, the temperature of the oxygen-containing gas can be raised, which improves the amount of heat recovered in the ammonia decomposition unit. In addition, by increasing the amount of heat recovered, the amount of ammonia and oxygen consumed in the combustion of the burner 44 can be reduced, so the configuration of the ammonia decomposition unit 40 can be made more compact. 【0044】 In Embodiment 2, the entire amount of ammonia-containing gas flowing through the ammonia supply line 5 was supplied to the burner 44, but the system is not limited to this configuration. An oxygen branch line may be branched from the oxygen supply line 7 and connected to the reactor 2 so as to communicate with the inside of the catalyst 3. In this configuration, a portion of the oxygen-containing gas flowing through the oxygen supply line 7 is supplied into the catalyst 3. When the oxygen branch line communicates with the inside of the catalyst 3, an ammonia branch line may be branched from the ammonia supply line 5 and connected to the reactor 2 so as to communicate with the inside of the catalyst 3. In this configuration, a portion of the ammonia-containing gas flowing through the ammonia supply line 5 is also supplied into the catalyst 3. Several specific and exemplary configurations of such a system are described below. 【0045】 As shown in Figure 8, the catalyst 3 is arranged in the reactor 2 in a configuration divided into at least two stages in the direction from the burner 44 toward the outflow gas line 8. Figure 8 illustrates a configuration in which the catalyst 3 is divided into three stages 3a, 3b, and 3c. The oxygen branch line 52, which branches off from the oxygen supply line 7, is configured to communicate with the two spaces 50a and 50b formed between adjacent stages 3a, 3b and between stages 3b, 3c, respectively. 【0046】 In the configuration shown in Figure 8, the oxygen-containing gas flowing into spaces 50a and 50b via the oxygen branching line 52 moves to stages 3a-3c of catalyst 3 and mixes with the mixed gas flowing into catalyst 3 from the upstream space 2a. This allows a portion of the ammonia to be oxidized within catalyst 3. In other words, both the ammonia decomposition reaction shown in reaction equation (1) and the ammonia oxidation reaction occur within catalyst 3. The heat generated during the oxidation of ammonia can be used to generate the ammonia decomposition reaction, which is an endothermic reaction. This allows for maintaining an appropriate temperature for the ammonia decomposition reaction and sustaining the reaction. 【0047】 When oxidizing ammonia, if the ammonia-containing gas and oxygen-containing gas are mixed outside the reactor 2 and this mixed gas is supplied to the catalyst 3, there is a risk of explosion when the ammonia-containing gas and oxygen-containing gas are mixed. However, this phenomenon will not occur unless the oxygen and ammonia are mixed in the narrow region of the piping. In the configuration shown in Figure 8, the oxygen-containing gas flowing into spaces 50a and 50b diffuses within the catalyst 3 and is sufficiently diluted, reducing the oxygen concentration to below the explosive zone, thus making such an explosion unlikely. 【0048】 Figure 9 illustrates a configuration in which not only oxygen-containing gas but also a portion of ammonia-containing gas is supplied to the catalyst 3, in contrast to the configuration in Figure 8. In the exemplary configuration of Figure 9, the catalyst 3 is divided into five stages 3a, 3b, 3c, 3d, and 3e. The ammonia branch line 51, which branches off from the ammonia supply line 5, communicates with two spaces 50a and 50c formed between adjacent stages 3a and 3b and between stages 3c and 3d, respectively. The oxygen branch line 52, which branches off from the oxygen supply line 7, is configured to communicate with spaces that do not communicate with the ammonia branch line 51, i.e., two spaces 50b and 50d formed between adjacent stages 3b and 3c and between stages 3d and 3e, respectively. 【0049】 In Figure 9, the ammonia branch line 51 and the oxygen branch line 52 are connected to different spaces; that is, they are configured so that neither the ammonia branch line 51 nor the oxygen branch line 52 is connected to the same space. However, a configuration in which both the ammonia branch line 51 and the oxygen branch line 52 are connected to the same space is also possible. 【0050】 In the configuration shown in Figure 9, the ammonia-containing gas and the oxygen-containing gas are supplied to separate spaces, so they are supplied to the catalyst 3 separately without mixing, and then mixed within the catalyst 3. This further reduces the risk of explosion when the ammonia-containing gas and the oxygen-containing gas are mixed. However, as mentioned above, the oxygen-containing gas that flows into the space within the catalyst 3 diffuses within the catalyst 3 and is sufficiently diluted, so the possibility of such an explosion is low. Therefore, even in a configuration where the ammonia-containing gas and the oxygen-containing gas are supplied to a single space, the possibility of such an explosion is low. 【0051】 As shown in Figure 10, at least one piping member is arranged within the catalyst 3 in the reactor 2. Figure 10 illustrates a configuration in which two piping members 60a and 60b are arranged within the catalyst 3. As shown in Figure 11, at least one hole 61 is formed in each of the piping members 60a and 60b so as to connect the inside and outside of the piping members 60a and 60b. As shown in Figure 10, it is preferable that each of the piping members 60a and 60b is spaced apart in the catalyst 3 in the direction from the burner 44 toward the outflow gas line. The oxygen branch line 52 is in communication with each of the piping members 60a and 60b. 【0052】 In the configuration shown in Figure 10, the oxygen-containing gas that flows into piping members 60a and 60b via the oxygen branching line 52 flows out to the outside of each piping member through holes 61 (see Figure 11) formed in each piping member. The oxygen-containing gas that flows out to the outside of each piping member mixes with the mixed gas that flows into the catalyst 3 from the upstream space 2a. This allows a portion of the ammonia to be oxidized within the catalyst 3. Even with the configuration shown in Figure 10, it is possible to maintain a temperature appropriate for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0053】 Furthermore, Figure 12 illustrates a configuration in which not only oxygen-containing gas but also a portion of ammonia-containing gas is supplied into the catalyst 3, in contrast to the configuration in Figure 10. In the exemplary configuration of Figure 12, four piping members 60a, 60b, 60c, and 60d are arranged within the catalyst 3. Note that the configurations of piping members 60c and 60d are the same as those of piping members 60a and 60b. The ammonia branch line 51 is connected to piping members 60a and 60c, respectively, and the oxygen branch line 52 is connected to piping members 60b and 60d. 【0054】 In Figure 12, the ammonia branch line 51 and the oxygen branch line 52 are connected to different piping members, meaning that both the ammonia branch line 51 and the oxygen branch line 52 are not connected to the same piping member. However, it is also possible to have a piping member to which both the ammonia branch line 51 and the oxygen branch line 52 are connected. 【0055】 In the configuration shown in Figure 12, the ammonia-containing gas and the oxygen-containing gas are supplied to separate piping members, and the ammonia-containing gas and oxygen-containing gas supplied to each piping member flow out to the outside of each piping member through holes 61 (see Figure 11) formed in each piping member. The ammonia-containing gas and oxygen-containing gas that have flowed out to the outside of each piping member are mixed in the catalyst 3. This allows the ammonia to be oxidized in the catalyst 3, and as a result, the temperature appropriate for the ammonia decomposition reaction can be maintained, and the ammonia decomposition reaction can be sustained. Even in a configuration where the ammonia-containing gas and oxygen-containing gas are supplied to a single piping member, the possibility of explosion occurring when the ammonia-containing gas and oxygen-containing gas mix is ​​low for the same reasons as described above in the configuration shown in Figure 9. 【0056】 The contents described in each of the above embodiments can be understood, for example, as follows: 【0057】 [1] An ammonia decomposition apparatus according to one embodiment is: A reactor (2) filled with a catalyst (3) for a decomposition reaction that decomposes the raw material ammonia into hydrogen and nitrogen, A burner (4) provided in the reactor (2) upstream of the catalyst (3), the burner (4) for burning hydrogen, Upstream of the catalyst (3), there is an ammonia supply line (5) for supplying ammonia into the reactor (2) and It is equipped with. 【0058】 According to the ammonia decomposition apparatus of this disclosure, by using the heat of combustion of hydrogen by the burner as heat to cause the ammonia decomposition reaction, which is an endothermic reaction, it becomes unnecessary to raise the temperature of the ammonia flowing through the ammonia supply line, or the degree of temperature rise of the ammonia can be suppressed, thereby preventing the ammonia supply line from nitriding due to the reaction between the high-temperature ammonia flowing through the ammonia supply line and the metal material of the ammonia supply line. 【0059】 [2] An ammonia decomposition apparatus according to another embodiment is the ammonia decomposition apparatus of [1], A hydrogen supply line (6) for supplying hydrogen-containing gas containing hydrogen to the burner (4), The exhaust gas containing hydrogen and nitrogen produced by the decomposition of ammonia in the reactor (2) flows through the exhaust gas line (8) after it has left the reactor (2). Equipped with, The hydrogen supply line (6) branches off from the exhaust gas line (8). 【0060】 With this configuration, by using hydrogen-containing effluent gas as hydrogen-containing gas, it becomes unnecessary to supply hydrogen from outside the ammonia decomposition unit, allowing the ammonia decomposition unit to operate independently without relying on external equipment. 【0061】 [3] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of [2], A first heat exchanger (12) in which the outflow gas flowing through the outflow gas line (8) and the hydrogen-containing gas flowing through the hydrogen supply line (6) exchange heat, A second heat exchanger (13) in which the outflow gas after heat exchange with the hydrogen-containing gas in the first heat exchanger (12) and ammonia-containing gas containing ammonia flowing through the ammonia supply line (5) exchange heat. It is equipped with. 【0062】 When the effluent gas immediately discharged from the reactor exchanges heat with the ammonia-containing gas, the temperature of the effluent gas is too high, causing the temperature of the ammonia-containing gas to become excessively high, which may lead to nitridation of the ammonia supply line. In contrast, with the configuration of [3], the effluent gas discharged from the reactor exchanges heat with the hydrogen-containing gas, and the effluent gas, now at a temperature lower than when it discharged from the reactor, exchanges heat with the ammonia-containing gas. This raises the temperature of the ammonia-containing gas to a level that does not cause nitridation of the ammonia supply line, thus suppressing nitridation of the ammonia supply line. Furthermore, since the temperatures of both the ammonia-containing gas and the hydrogen-containing gas can be raised, the amount of heat recovered in the ammonia decomposition unit can be improved. 【0063】 [4] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of [3], An oxygen supply line (7) for supplying oxygen-containing gas containing oxygen to the burner (4), A third heat exchanger (30) in which the oxygen-containing gas flowing through the oxygen supply line (7) and the outflow gas after heat exchange with the hydrogen-containing gas in the first heat exchanger (12) exchange heat. Equipped with, The third heat exchanger (30) is configured such that the outflow gas, after heat exchange with the oxygen-containing gas, and the ammonia-containing gas flowing through the ammonia supply line (5) undergo heat exchange in the second heat exchanger (13). 【0064】 With this configuration, after the effluent gas flowing out of the reactor and the hydrogen-containing gas exchange heat, the effluent gas and the oxygen-containing gas exchange heat again. The effluent gas, now at a temperature lower than when it flowed out of the reactor, then exchanges heat with the ammonia-containing gas. This allows the temperature of the ammonia-containing gas to be raised to a level that does not cause nitriding of the ammonia supply line, thus suppressing nitriding of the ammonia supply line. Furthermore, since the temperatures of both the ammonia-containing gas and the hydrogen-containing gas can be raised, the amount of heat recovered in the ammonia decomposition unit can be improved. In addition, the increased heat recovery allows for a reduction in the amount of hydrogen and oxygen consumed in the combustion of the burner, making the configuration of the ammonia decomposition unit more compact. 【0065】 [5] An ammonia decomposition apparatus according to yet another embodiment is an ammonia decomposition apparatus according to any of [2] to [4], The outlet gas line (8) is provided with an ammonia recovery device (9) for recovering ammonia from the outlet gas, The hydrogen supply line (6) branches off from the outflow gas line (8) downstream of the ammonia recovery device (9). 【0066】 The effluent gas contains hydrogen and nitrogen as well as unreacted ammonia, but according to the configuration of [5], the effluent gas after ammonia has been removed in the ammonia recovery unit is supplied to the burner as hydrogen-containing gas, so that the consumption of some of the unreacted ammonia by combustion in the burner can be suppressed. 【0067】 [6] An ammonia decomposition apparatus according to yet another embodiment is an ammonia decomposition apparatus according to any of [2] to [4], The outlet gas line (8) is provided with an ammonia recovery device (9) for recovering ammonia from the outlet gas, The hydrogen supply line (6) branches off from the outflow gas line (8) upstream of the ammonia recovery device (9). 【0068】 This configuration can be adopted when the ammonia decomposition rate in the reactor is high and there is little unreacted ammonia in the effluent gas. By adopting this configuration, a portion of the effluent gas can be supplied to the burner as hydrogen-containing gas without pressure loss in the ammonia recovery equipment or heat loss due to cooling in this equipment, thus improving the overall energy efficiency of the ammonia decomposition system. 【0069】 [7] An ammonia decomposition apparatus according to yet another embodiment is an ammonia decomposition apparatus according to any of [2] to [6], The hydrogen supply line (6) is provided with a nitrogen removal device (20) that removes nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line (6). 【0070】 With this configuration, the volumetric flow rate of the hydrogen-containing gas supplied to the burner can be reduced, which in turn reduces the size of the hydrogen supply line and, if a compressor for pressurizing the hydrogen-containing gas is installed in the hydrogen supply line, the size of the compressor can also be reduced. As a result, the ammonia decomposition unit can be made more compact. 【0071】 [8] An ammonia decomposition apparatus according to one embodiment is: A reactor (2) filled with a catalyst for a decomposition reaction (3) that decomposes the raw material ammonia into hydrogen and nitrogen, A burner (44) provided in the reactor (2) upstream of the catalyst (3), the burner (44) for burning a portion of the ammonia of the raw material, An ammonia supply line (5) for supplying an ammonia-containing gas, which includes the aforementioned raw material ammonia, to the burner (44), The outlet gas line (8) through which the effluent gas containing hydrogen and nitrogen, produced by the decomposition of ammonia in the reactor (2), flows after it has left the reactor (2), A first heater (43) for heating the ammonia-containing gas flowing through the ammonia supply line (5), wherein the ammonia-containing gas and the outflow gas flowing through the outflow gas line (8) exchange heat in the first heater (43), Upstream of the first heater (43), there is a hydrogen supply line (46) that supplies hydrogen-containing gas containing hydrogen to the ammonia-containing gas flowing through the ammonia supply line (5), and It is equipped with. 【0072】 According to the ammonia decomposition apparatus of this disclosure, the ammonia-containing gas is heated in a first heater installed in the ammonia supply line for supplying ammonia-containing gas to the burner. Therefore, downstream of the first heater, there is a risk that the ammonia will react with the metal material of the ammonia supply line and cause nitridation of the ammonia supply line. However, by supplying a hydrogen-containing gas to the ammonia-containing gas upstream of the first heater, the concentration of ammonia in the ammonia-containing gas decreases, thereby suppressing nitridation of the ammonia supply line downstream of the first heater. 【0073】 [9] An ammonia decomposition apparatus according to another embodiment is the ammonia decomposition apparatus of [8], The hydrogen supply line (46) branches off from the outlet gas line (8) downstream of the first heater (43). 【0074】 With this configuration, by using hydrogen-containing effluent gas as hydrogen-containing gas, it becomes unnecessary to supply hydrogen from outside the ammonia decomposition unit, allowing the ammonia decomposition unit to operate independently without relying on external equipment. 【0075】

[10] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of [8] or [9], An oxygen supply line (7) for supplying oxygen-containing gas containing oxygen to the burner (44), An oxygen branch line (52) branches off from the oxygen supply line (7) and supplies a portion of the oxygen-containing gas into the catalyst (3). It is equipped with. 【0076】 With this configuration, the heat generated when a portion of the ammonia is oxidized in the catalyst located downstream of the burner in the reactor can be used as heat to cause the endothermic reaction of ammonia decomposition. This allows for maintaining an appropriate temperature for the ammonia decomposition reaction and sustaining the reaction. 【0077】

[11] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of

[10] , The catalyst (3) is divided into at least two stages (3a, 3b, 3c, 3d, 3e) and arranged in the direction from the burner (44) toward the outflow gas line (8), The oxygen branching line (52) is configured to communicate with at least one space (50a, 50b, 50c, 50d) formed between adjacent stages. 【0078】 With this configuration, similar to the configuration in

[10] , it is possible to maintain a temperature suitable for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0079】

[12] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of

[10] , The catalyst (3) is provided with at least one piping member (60a, 60b, 60c, 60d), Each of the aforementioned at least one piping member (60a, 60b, 60c, 60d) has at least one hole (61) formed therein so as to communicate the inside and outside of the piping member. The oxygen branch line (52) is configured to communicate with at least one of the piping members (60a, 60b, 60c, 60d). 【0080】 With this configuration, similar to the configuration in

[10] , it is possible to maintain a temperature suitable for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0081】

[13] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of

[10] , The system includes an ammonia branch line (51) that branches off from the ammonia supply line (5) and supplies a portion of the ammonia-containing gas flowing through the ammonia supply line (5) into the catalyst (3). 【0082】 With this configuration, similar to the configuration in

[10] , it is possible to maintain a temperature suitable for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0083】

[14] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of

[13] , The catalyst (3) is divided into at least two stages (3a, 3b, 3c, 3d, 3e) and arranged in the direction from the burner (44) toward the outflow gas line (8), The ammonia branch line (51) is configured to communicate with at least one of the at least one spaces (50a, 50b, 50c, 50d) formed between adjacent stages, and the oxygen branch line (52) is configured to communicate with at least one of the at least one spaces (50a, 50b, 50c, 50d). 【0084】 With this configuration, similar to the configuration in

[10] , it is possible to maintain a temperature suitable for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0085】

[15] An ammonia decomposition apparatus according to yet another embodiment is the ammonia decomposition apparatus of

[13] , The catalyst (3) is provided with at least one piping member (60a, 60b, 60c, 60d), Each of the aforementioned at least one piping member (60a, 60b, 60c, 60d) has at least one hole (61) formed therein so as to communicate the inside and outside of the piping member (60a, 60b, 60c, 60d), The ammonia branch line (51) is configured to communicate with at least one of the at least one piping member (60a, 60b, 60c, 60d), and the oxygen branch line (52) is configured to communicate with at least one of the at least one piping member (60a, 60b, 60c, 60d). 【0086】 With this configuration, similar to the configuration in

[10] , it is possible to maintain a temperature suitable for the ammonia decomposition reaction and sustain the ammonia decomposition reaction. 【0087】

[16] An ammonia decomposition apparatus according to yet another embodiment is an ammonia decomposition apparatus of any of [8] to

[15] , The system includes a nitrogen removal device (20) provided in the hydrogen supply line (46) for removing nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line (46). 【0088】 With this configuration, the volumetric flow rate of hydrogen-containing gas supplied to the ammonia-containing gas flowing through the ammonia supply line can be reduced, thereby reducing the size of the hydrogen supply line and the ammonia supply line, and as a result, the ammonia decomposition unit can be made more compact. 【0089】

[17] An ammonia decomposition apparatus according to yet another embodiment is an ammonia decomposition apparatus according to any of [8] to

[16] , An oxygen supply line (7) for supplying oxygen-containing gas containing oxygen to the burner (44), The system includes a second heater (45) in which the oxygen-containing gas flowing through the oxygen supply line (7) and the effluent gas discharged from the reactor (2) exchange heat. The second heater (45) is configured to exchange heat with the oxygen-containing gas, and the resulting outflow gas and the ammonia-containing gas flowing through the ammonia supply line (5) are then heat-exchanged in the first heater (43). 【0090】 This configuration allows for the heating of the oxygen-containing gas, thereby improving the heat recovery rate in the ammonia decomposition unit. Furthermore, the increased heat recovery rate reduces the amount of ammonia and oxygen consumed in the burner's combustion, allowing for a more compact ammonia decomposition unit. [Explanation of Symbols] 【0091】 1. Ammonia decomposition device 2 Reactors 3 Catalyst 3a,3b,3c,3d,3e (catalyst) stage 4 burners 5. Ammonia supply line 6. Hydrogen supply line 7. Oxygen supply line 8. Outflow gas line 9. Ammonia recovery unit 12 1st heat exchanger 13 Second heat exchanger 20 Nitrogen removal equipment 30 Third heat exchanger 40 Ammonia decomposition device 43 1st heater 44 Burner 45 Second heater 46 Hydrogen supply line 50a,50b,50c,50d space 51 Ammonia branch line 52 Oxygen branching line 60a, 60b, 60c, 60d Piping components 61 holes

Claims

[Claim 1] A reactor filled with a catalyst for a decomposition reaction that breaks down the raw material ammonia into hydrogen and nitrogen, A burner provided in the reactor upstream of the catalyst, comprising a burner for burning hydrogen, An ammonia supply line for supplying ammonia into the reactor upstream of the catalyst, An ammonia decomposition device equipped with the following features. [Claim 2] A hydrogen supply line for supplying hydrogen-containing gas to the burner, The effluent gas containing hydrogen and nitrogen produced by the decomposition of ammonia in the reactor flows through the effluent gas line after it has left the reactor. Equipped with, The ammonia decomposition apparatus according to claim 1, wherein the hydrogen supply line branches off from the outlet gas line. [Claim 3] A first heat exchanger in which the outflow gas flowing through the outflow gas line and the hydrogen-containing gas flowing through the hydrogen supply line exchange heat, A second heat exchanger in which the outflow gas after heat exchange with the hydrogen-containing gas in the first heat exchanger and an ammonia-containing gas containing ammonia flowing through the ammonia supply line exchange heat. The ammonia decomposition apparatus according to claim 2, comprising: [Claim 4] An oxygen supply line for supplying oxygen-containing gas to the burner, A third heat exchanger in which the oxygen-containing gas flowing through the oxygen supply line and the outflow gas after heat exchange with the hydrogen-containing gas in the first heat exchanger exchange heat. Equipped with, The ammonia decomposition apparatus according to claim 3, wherein the outlet gas after heat exchange with the oxygen-containing gas in the third heat exchanger and the ammonia-containing gas flowing through the ammonia supply line are configured to undergo heat exchange in the second heat exchanger. [Claim 5] The aforementioned outflow gas line is equipped with an ammonia recovery device for recovering ammonia from the outflow gas, The ammonia decomposition apparatus according to any one of claims 2 to 4, wherein the hydrogen supply line branches off from the outflow gas line downstream of the ammonia recovery apparatus. [Claim 6] The aforementioned outflow gas line is equipped with an ammonia recovery device for recovering ammonia from the outflow gas, The ammonia decomposition apparatus according to any one of claims 2 to 4, wherein the hydrogen supply line branches off from the outflow gas line upstream of the ammonia recovery apparatus. [Claim 7] The ammonia decomposition apparatus according to any one of claims 2 to 4, further comprising a nitrogen removal device provided in the hydrogen supply line for removing nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line. [Claim 8] A reactor filled with a catalyst for a decomposition reaction that breaks down the raw material ammonia into hydrogen and nitrogen, A burner provided in the reactor upstream of the catalyst, comprising a burner for burning a portion of the ammonia of the raw material, An ammonia supply line for supplying ammonia-containing gas, which includes the aforementioned raw material ammonia, to the burner, The outlet gas line through which the effluent gas containing hydrogen and nitrogen, produced by the decomposition of ammonia in the reactor, flows after it has left the reactor, A first heater for heating the ammonia-containing gas flowing through the ammonia supply line, the first heater in which the ammonia-containing gas and the outflow gas flowing through the outflow gas line exchange heat, Upstream of the first heater, a hydrogen supply line supplies hydrogen-containing gas to the ammonia-containing gas flowing through the ammonia supply line. An ammonia decomposition device equipped with the following features. [Claim 9] The ammonia decomposition apparatus according to claim 8, wherein the hydrogen supply line branches off from the outflow gas line downstream of the first heater. [Claim 10] An oxygen supply line for supplying oxygen-containing gas to the burner, An oxygen branching line is branched from the oxygen supply line to supply a portion of the oxygen-containing gas into the catalyst. The ammonia decomposition apparatus according to claim 8 or 9, comprising: [Claim 11] The catalyst is divided into at least two stages of split catalysts and arranged in the direction from the burner toward the exhaust gas line, The ammonia decomposition apparatus according to claim 10, wherein the oxygen branching line is configured to communicate with at least one space formed between adjacent divided catalysts. [Claim 12] The catalyst comprises at least one piping member, Each of the aforementioned at least one piping member has at least one hole formed therein so as to communicate the inside and outside of the piping member. The ammonia decomposition apparatus according to claim 10, wherein the oxygen branch line is configured to communicate with at least one piping member. [Claim 13] The ammonia decomposition apparatus according to claim 10, further comprising an ammonia branch line that branches off from the ammonia supply line and supplies a portion of the ammonia-containing gas flowing through the ammonia supply line into the catalyst. [Claim 14] The catalyst is divided into at least two stages of split catalysts and arranged in the direction from the burner toward the exhaust gas line, The ammonia decomposition apparatus according to claim 13, wherein the ammonia branch line is configured to communicate with at least one of the at least one spaces formed between adjacent divided catalysts, and the oxygen branch line is configured to communicate with at least one of the at least one spaces. [Claim 15] The catalyst comprises at least one piping member, Each of the aforementioned at least one piping member has at least one hole formed therein so as to communicate the inside and outside of the piping member. The ammonia decomposition apparatus according to claim 13, wherein the ammonia branch line is configured to communicate with at least one of the at least one piping member, and the oxygen branch line is configured to communicate with at least one of the at least one piping member. [Claim 16] The ammonia decomposition apparatus according to claim 8 or 9, further comprising a nitrogen removal device provided in the hydrogen supply line for removing nitrogen from the hydrogen-containing gas flowing through the hydrogen supply line. [Claim 17] An oxygen supply line for supplying oxygen-containing gas to the burner, A second heater in which the oxygen-containing gas flowing through the oxygen supply line and the effluent gas discharged from the reactor exchange heat. Equipped with, The ammonia decomposition apparatus according to claim 8 or 9, wherein the outlet gas after heat exchange with the oxygen-containing gas in the second heater and the ammonia-containing gas flowing through the ammonia supply line are configured to undergo heat exchange in the first heater.

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