Liquid ammonia gasification device

Abstract

The invention relates to the technical field of liquid ammonia treatment, in particular to a liquid ammonia gasification device which comprises a first container and a second container, a heat preservation blocking structure is arranged between the opposite wall faces of the first container and the second container, and the first container is provided with a first inlet, a first containing cavity and a first outlet; the first container is provided with a first inlet, a first outlet and a second containing cavity, the first inlet and the first outlet both communicate with the first containing cavity, the second container is provided with a second inlet, a second containing cavity and a second outlet, and the second inlet and the second outlet both communicate with the second containing cavity; the multiple heat exchange pipes are distributed in the first containing cavity and the second containing cavity at intervals, the heat exchange pipes penetrate through the heat preservation blocking structure and then are arranged in the first containing cavity and the second containing cavity at the same time, the heat exchange pipes are suitable for containing first liquid ammonia, the first containing cavity is suitable for containing a heating medium, and the second containing cavity is suitable for containing second liquid ammonia; the pressure of the first liquid ammonia is greater than that of the second liquid ammonia. The problems that an existing liquid ammonia evaporator is high in energy consumption, low in heat exchange efficiency and prone to icing are solved.

Description

Technical Field

[0001] This invention relates to the field of liquid ammonia treatment technology, and more specifically to a liquid ammonia vaporization device. Background Technology

[0002] Ammonia, as a carbon-free energy carrier, has received widespread attention in the energy sector in recent years due to its advantages such as high hydrogen content (up to 17.6% by mass), ease of liquefaction and storage, and the absence of carbon dioxide production during combustion. Particularly in high-carbon-emission industries such as power, steel, and cement, ammonia-blended combustion (i.e., co-combustion with a certain proportion of ammonia in traditional fuels) is considered a crucial technological pathway for achieving deep decarbonization. However, ammonia-blended combustion faces numerous technical challenges in practical applications, a key aspect being the stable, efficient, and safe supply of sufficient gaseous ammonia. Since ammonia is a gas at room temperature and pressure, but is typically stored and transported as liquid ammonia in industry, the blending system requires a liquid ammonia evaporator to rapidly and controllably convert liquid ammonia into gaseous ammonia that meets combustion requirements. As the ammonia blending ratio increases, the required ammonia flow rate increases significantly, placing higher demands on the evaporator's evaporation capacity, response speed, thermal efficiency, and operational safety.

[0003] Existing liquid ammonia evaporators mostly employ high-quality steam heating, which suffers from high energy consumption, low heat exchange efficiency, and susceptibility to icing, making it difficult to meet the demands of high-flow, dynamically adjustable ammonia-blended combustion conditions. Therefore, there is an urgent need to develop a novel liquid ammonia evaporator with low energy consumption, high heat transfer efficiency, stable operation, and large evaporation capacity to support the reliable operation of high-proportion ammonia-blended combustion systems and promote the large-scale application of ammonia energy in the energy sector. Summary of the Invention

[0004] This invention provides a liquid ammonia vaporization device to solve the problems of high energy consumption, low heat exchange efficiency, and easy icing in existing liquid ammonia evaporators.

[0005] This invention provides a liquid ammonia vaporization device, comprising:

[0006] A first container and a second container are provided with a heat-insulating barrier structure between their opposing walls. The first container is provided with a first inlet, a first receiving cavity and a first outlet, both of which are connected to the first receiving cavity. The second container is provided with a second inlet, a second receiving cavity and a second outlet, both of which are connected to the second receiving cavity. Multiple heat exchange tubes are spaced apart in a first and a second accommodating cavity. The heat exchange tubes pass through the insulation barrier structure and are placed in both the first and second accommodating cavities. The heat exchange tubes are suitable for containing first liquid ammonia, the first accommodating cavity is suitable for containing a heating medium, and the second accommodating cavity is suitable for containing second liquid ammonia. The pressure of the first liquid ammonia is greater than that of the second liquid ammonia. After exchanging heat with the heating medium, the first liquid ammonia vaporizes into ammonia gas. After exchanging heat with the second liquid ammonia gas again, the ammonia gas liquefies. The second liquid ammonia gas vaporizes into ammonia gas and is then output through a second outlet.

[0007] Beneficial effects: After the heating medium enters the first containment chamber and exchanges heat with the first liquid ammonia in the heat exchange tube, the first liquid ammonia vaporizes into ammonia gas. The ammonia gas rises to the portion of the heat exchange tube located in the second containment chamber, where it exchanges heat again with the second liquid ammonia gas, liquefies, and flows back. This can be achieved through phase change, resulting in energy savings and high heat exchange efficiency. Simultaneously, the thermal insulation barrier structure between the first and second containers ensures that the ammonia gas does not experience localized low temperatures or even freezing due to evaporation and heat absorption, thus ensuring the normal operation of the device. Furthermore, compared to directly using power plant flue gas to heat liquid ammonia, in this embodiment, since the heating medium only contacts the portion of the heat exchange tube containing the first liquid ammonia, the flow velocity is higher, reducing fly ash deposition, decreasing wear and corrosion on the heat exchange tube, and preventing excessive exhaust emissions caused by ammonia leakage and mixing with the heating medium. It can also be connected to power plant exhaust, utilizing the large amount of waste heat from the exhaust, maximizing resource utilization. Since the core of liquid ammonia vaporization is the stable maintenance of gas-liquid balance, this invention can adjust the pressure of the first liquid ammonia to stabilize the vaporization temperature below the temperature range of the heating medium, so that the first liquid ammonia can stably absorb heat and vaporize, completely eliminating the interference of ambient temperature. The vaporization of the second liquid ammonia is driven by the latent heat after the vaporization of the first liquid ammonia. The phase change process is in a stable isothermal and isobaric state, and the temperature and pressure fluctuation range of the output ammonia gas is small.

[0008] In one alternative implementation, multiple heat exchange tubes are arrayed in a first and a second receiving cavity.

[0009] The distribution of multiple heat exchange tube arrays can significantly increase the total heat exchange area per unit volume within a limited heat exchange space, thereby improving heat exchange efficiency. On the other hand, it can guide the fluid to flow in an orderly manner within the heat exchange space, avoiding fluid "short circuits" or "dead zones" and ensuring the uniformity of heat exchange.

[0010] In one alternative embodiment, a baffle is provided between the two rows of heat exchange tubes near the second outlet in the second receiving cavity.

[0011] The baffle plate extends the flow path of ammonia gas in the second containment chamber, allowing it to absorb heat from the heat exchange tubes again and heat it to the required temperature, further improving energy utilization.

[0012] In one alternative embodiment, there are multiple baffles, which are staggered along the flow direction of ammonia.

[0013] The staggered arrangement of multiple baffles further prolongs the flow time of ammonia in the second containment chamber, making full use of the heat in the heat exchange tubes.

[0014] In one optional embodiment, the thermal insulation barrier structure includes a first partition that is attached to the wall of the first container, a second partition that is attached to the wall of the second container, and an insulation board disposed between the first partition and the second partition.

[0015] The first and second partitions can effectively prevent the heating medium in the first cavity from mixing with the second liquid ammonia in the second cavity, while the insulation plate prevents the heat from being conducted between the first and second cavities.

[0016] In one alternative implementation, both the first partition and the second partition are metal partitions.

[0017] Metal partitions are strong and have good sealing properties, making them less susceptible to corrosion and damage.

[0018] In one alternative embodiment, fins are provided on the outer wall of the heat exchange tube.

[0019] The fins increase the contact area between the fluids inside and outside the heat exchange tube, further improving the heat exchange efficiency.

[0020] In one alternative embodiment, the fins of the heat exchange tube in the first receiving cavity are annular fins, and the fins of the heat exchange tube in the second receiving cavity are serrated fins extending axially parallel to the heat exchange tube.

[0021] The outer wall of the heat exchange tube in the first cavity is provided with annular fins, which allows the heating medium to flow circumferentially along the heat exchange tube in the first cavity with low resistance. The outer wall of the heat exchange tube in the second cavity is provided with axially extending serrated fins because the second liquid ammonia will move from bottom to top after being vaporized into ammonia gas, and the axially extending serrated fins have low resistance.

[0022] In one alternative embodiment, the first liquid ammonia is filled to 1 / 4 to 1 / 3 of the heat exchange tube volume.

[0023] The above-mentioned filling amount ensures that the pressure in the heat exchange tubes will not increase sharply after the liquid ammonia is vaporized, making the entire device operate more safely and stably.

[0024] In one alternative implementation, the heating medium is low-temperature hot water, low-temperature steam, hot air, or low-temperature flue gas.

[0025] The above method makes full use of the heat of the power plant's exhaust gas to vaporize liquid ammonia, thus saving energy. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a front view of the liquid ammonia vaporization device according to an embodiment of the present invention; Figure 2 This is a top view of the liquid ammonia vaporization device according to an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached figures: 1. First container; 101. First inlet; 102. First receiving cavity; 103. First outlet; 2. Second container; 201. Second inlet; 202. Second receiving cavity; 203. Second outlet; 3. Thermal insulation barrier structure; 301. First partition; 302. Second partition; 303. Thermal insulation plate; 4. Heat exchange tube; 5. Baffle plate; 6. Fins. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The following is combined Figure 1 and Figure 2 Embodiments of the present invention are described.

[0031] According to an embodiment of the present invention, a liquid ammonia vaporization apparatus is provided, comprising: A first container 1 and a second container 2 are provided with a heat-insulating barrier structure 3 between their opposing walls. The first container 1 is provided with a first inlet 101, a first receiving cavity 102 and a first outlet 103. The first inlet 101 and the first outlet 103 are both connected to the first receiving cavity 102. The second container 2 is provided with a second inlet 201, a second receiving cavity 202 and a second outlet 203. The second inlet 201 and the second outlet 203 are both connected to the second receiving cavity 202. Multiple heat exchange tubes 4 are spaced apart in the first receiving cavity 102 and the second receiving cavity 202. The heat exchange tubes 4 pass through the heat insulation barrier structure 3 and are placed in the first receiving cavity 102 and the second receiving cavity 202. The heat exchange tubes 4 are suitable for containing the first liquid ammonia, the first receiving cavity 102 is suitable for containing the heating medium, and the second receiving cavity 202 is suitable for containing the second liquid ammonia. The pressure of the first liquid ammonia is greater than the pressure of the second liquid ammonia. After the first liquid ammonia exchanges heat with the heating medium, it vaporizes into ammonia gas. After the ammonia gas exchanges heat with the second liquid ammonia again, it liquefies. After the second liquid ammonia vaporizes into ammonia gas, it is output through the second outlet 203.

[0032] Both the first container 1 and the second container 2 are made of high-temperature and corrosion-resistant alloy material. Their shapes can be cuboids, cubes, or cylinders, etc., without specific limitations. Their dimensions are identical to ensure stability when stacked. Typically, the volume of the first container 1 is larger than that of the second container 2 to ensure sufficient heat for the vaporization of the first liquid ammonia and the subsequent vaporization of the second liquid ammonia. However, the volume of the first container 1 can also be smaller or equal to that of the second container 2, without specific limitations. The first inlet 101 and the first outlet 103 are diagonally distributed, as are the second inlet 201 and the second outlet 203. The first inlet 101 and the second inlet 201 are positioned opposite each other, and the first outlet 103 and the second outlet 203 are positioned opposite each other to ensure sufficient heat exchange and maximize heat exchange efficiency. Of course, the positions of the first inlet 101, the first outlet 103, the second inlet 201, and the second outlet 203 can be flexibly adjusted according to requirements, without specific limitations.

[0033] The heat exchange tube 4 extends from the bottom of the first receiving cavity 102 to the top of the second receiving cavity 202. The heat exchange tube 4 in the first receiving cavity 102 is the evaporation section, and the heat exchange tube 4 in the second receiving cavity 202 is the condensation section. One end of the heat exchange tube 4 is provided with a liquid ammonia injection port, which is equipped with a valve for easy adjustment of the injection volume. The pressure of the first liquid ammonia in the heat exchange tube 4 is about 1.0 MPa, the corresponding saturation temperature is about 20°C, and the temperature of the heating medium is about 50°C. After heat exchange, the first liquid ammonia is vaporized into ammonia gas at a temperature of about 40°C and rises along the center of the heat exchange tube 4 to the condensation section. The heating medium cools down to about 30°C and flows out from the first outlet 103. The pressure of the second liquid ammonia is about 20 kPa, the corresponding saturation temperature is about -30°C, and after heat exchange with the ammonia gas in the heat exchange tube 4, it is discharged from the second outlet 203. The ammonia gas in the heat exchange tube 4 releases heat and flows back to the bottom along the side wall of the heat exchange tube 4, realizing circulation. The heat exchange tube 4 serves the functions of evaporation and condensation simultaneously, which is simple in structure, low in cost, and enables the recycling of liquid ammonia.

[0034] Beneficial effects: After the heating medium enters the first receiving cavity 102 and exchanges heat with the first liquid ammonia in the heat exchange tube 4, the first liquid ammonia vaporizes into ammonia gas. The ammonia gas rises to the portion of the heat exchange tube 4 located in the second receiving cavity 202, where it exchanges heat with the second liquid ammonia again, liquefies, and flows back. This can be achieved through phase change, saving energy while maintaining high heat exchange efficiency. Simultaneously, the insulation barrier structure 3 between the first container 1 and the second container 2 ensures that the ammonia gas will not experience localized low temperatures or even freezing due to evaporation and heat absorption, ensuring the normal operation of the device. Furthermore, compared to directly using power plant flue gas to heat liquid ammonia, in this embodiment of the invention, since the heating medium only contacts the portion of the heat exchange tube 4 containing the first liquid ammonia, the flow rate is higher here, reducing fly ash deposition, decreasing wear and corrosion of the heat exchange tube 4, and preventing excessive exhaust emissions caused by ammonia leakage and mixing with the heating medium. It can also be connected to power plant exhaust, utilizing a large amount of waste heat from the exhaust, maximizing resource utilization. Since the core of liquid ammonia vaporization is the stable maintenance of gas-liquid balance, this invention can stabilize the vaporization temperature in a temperature range lower than that of the heating medium by adjusting the pressure of the first liquid ammonia. This allows the first liquid ammonia to stably absorb heat and vaporize, completely eliminating the interference of ambient temperature. The vaporization of the second liquid ammonia is driven by the latent heat after the vaporization of the first liquid ammonia. The phase change process is in a stable isothermal and isobaric state, and the temperature and pressure fluctuation range of the output ammonia gas is small.

[0035] In one embodiment, a plurality of heat exchange tubes 4 are arrayed in the first receiving cavity 102 and the second receiving cavity 202.

[0036] like Figure 2 As shown, multiple heat exchange tubes 4 are arranged in rows and columns in the first receiving cavity 102 and the second receiving cavity 202, that is, they are completely aligned. Of course, the heat exchange tubes 4 in adjacent rows or columns can also be staggered, which is not specifically limited here.

[0037] The distribution of multiple heat exchange tubes in an array can significantly increase the total heat exchange area per unit volume within a limited heat exchange space, thereby improving heat exchange efficiency. On the other hand, it can guide the fluid to flow in an orderly manner within the heat exchange space, avoiding fluid "short circuits" or "dead zones" and ensuring the uniformity of heat exchange.

[0038] In one embodiment, a baffle 5 is provided between the two rows of heat exchange tubes 4 near the second outlet 203 in the second receiving cavity 202.

[0039] like Figure 1 and Figure 2 As shown, the baffle 5 is a flat plate with one end fixed to the top or bottom wall of the second container 2 and extending vertically to further divide the heat exchange space between two adjacent rows of heat exchange tubes 4, so as to extend the heat exchange time of ammonia in a limited space, thereby allowing ammonia to further absorb the heat from the condensation section of the heat exchange tubes 4 and transform into superheated ammonia to meet the actual needs.

[0040] The baffle 5 extends the flow path of ammonia in the second containment chamber 202, allowing it to absorb heat from the heat exchange tube 4 again and heat it to the required temperature, further improving energy utilization.

[0041] In one embodiment, there are multiple baffles 5, which are staggered along the flow direction of ammonia gas.

[0042] like Figure 1 and Figure 2 As shown, the two baffles 5 are staggered. Specifically, the top end of one baffle 5 is fixed to the top wall of the first container 1, while the bottom end is spaced apart from the bottom wall of the first container 1. The bottom end of the other baffle 5 is fixed to the bottom of the first container 1, while the top end is spaced apart from the top wall of the first container 1, thus forming two bends. The other two ends of the baffles 5 are fixed to the two opposite side walls of the first container 1. Of course, the number of baffles 5 can be increased according to needs, and no specific limit is made here.

[0043] The staggered arrangement of multiple baffles 5 further prolongs the flow time of ammonia in the second containment cavity 202, making full use of the heat in the heat exchange tube 4.

[0044] In one embodiment, the thermal insulation barrier structure 3 includes a first partition 301 that is attached to the wall of the first container 1, a second partition 302 that is attached to the wall of the second container 2, and a thermal insulation board 303 disposed between the first partition 301 and the second partition 302.

[0045] The first partition 301 and the second partition 302 are rectangular flat plates with the same dimensions and shape as the top wall of the first container 1 and the bottom wall of the second container 2. The insulation board 303 can be fixed in the middle by high-temperature resistant adhesive.

[0046] The first partition 301 and the second partition 302 can effectively prevent the heating medium in the first accommodating cavity 102 from mixing with the second liquid ammonia in the second accommodating cavity 202, while the insulation plate 303 avoids the mutual conduction of heat between the first accommodating cavity 102 and the second accommodating cavity 202.

[0047] In one embodiment, both the first partition 301 and the second partition 302 are metal partitions.

[0048] The metal partition is made of high-temperature resistant material, preferably alloy material, but other high-temperature resistant metal materials can also be selected; no specific restrictions are imposed here. The metal partition has high strength, good sealing properties, and is not easily corroded or damaged.

[0049] In one embodiment, fins 6 are provided on the outer wall of the heat exchange tube 4.

[0050] The fins 6 are arranged at intervals along the circumference of the heat exchange tube 4. They can be integrally formed with the heat exchange tube 4 or welded and fixed, without specific restrictions. The arrangement of the fins 6 increases the contact area between the fluids inside and outside the heat exchange tube 4, further improving the heat exchange efficiency.

[0051] In one embodiment, the fins 6 of the heat exchange tube 4 located in the first receiving cavity 102 are annular fins, and the fins 6 of the heat exchange tube 4 located in the second receiving cavity 202 are serrated fins extending parallel to the axial direction of the heat exchange tube 4.

[0052] like Figure 1 As shown, the annular fins are spaced apart along the axial direction of the heat exchange tube 4, and the specific gap can be set according to actual needs; the serrated fins are spaced apart along the circumferential direction of the heat exchange tube 4, and the shape of the fins 6 can also be other shapes, such as wavy, without specific restrictions here.

[0053] The outer wall of the heat exchange tube 4 in the first receiving cavity 102 is provided with annular fins, so that the heating medium can flow in the first receiving cavity 102 along the circumference of the heat exchange tube 4 with less resistance; the outer wall of the heat exchange tube 4 in the second receiving cavity 202 is provided with axially extending serrated fins, because the second liquid ammonia will move from bottom to top after being vaporized into ammonia gas, and the axially extending serrated fins have less resistance.

[0054] In one embodiment, the amount of the first liquid ammonia filling is 1 / 4 to 1 / 3 of the volume of the heat exchange tube 4.

[0055] Because liquid ammonia expands in volume after absorbing heat and vaporizing, if the amount of the first liquid ammonia filling is too large, it may affect the normal operation of heat exchange tube 4. Therefore, the above filling amount ensures that the pressure in heat exchange tube 4 will not increase sharply after the liquid ammonia vaporizes, making the whole device operate more safely and stably.

[0056] In one embodiment, the heating medium is low-temperature hot water, low-temperature steam, hot air, or low-temperature flue gas.

[0057] Waste heat from power plants includes low-temperature hot water, low-temperature steam, hot air, or low-temperature flue gas. This waste heat is usually low in heat and contains certain impurities, but the quantity is huge. If it is directly discharged, the heat loss will be large. The above methods make full use of the heat of waste heat from power plants to vaporize liquid ammonia, thus saving energy.

[0058] The specific process for vaporizing liquid ammonia using the liquid ammonia vaporization device in this embodiment is as follows: The heating medium enters the first container 1 through the first inlet 101 and exchanges heat with the evaporation section of the heat exchange tube 4. The heating medium is at approximately 50°C. The heat exchange tube 4 is filled with a first liquid ammonia with a positive pressure of approximately 1.0 MPa (corresponding to a liquid ammonia saturation temperature of approximately 20°C). When the heating medium comes into contact with the evaporation section of the heat exchange tube 4, heat exchange occurs. Since the temperature of the heating medium is higher than the temperature of the first liquid ammonia in the evaporation section, the first liquid ammonia in the evaporation section is heated from 20°C to approximately 40°C, and its state changes from liquid to gas. The gaseous ammonia rises inside the heat exchange tube 4 to the condensation section of the heat exchange tube 4. After the heating medium exchanges heat with the evaporation section of the heat exchange tube 4, it drops to approximately 30°C and is then discharged to a designated location through the first outlet 103.

[0059] The second liquid ammonia enters the second container 2 through the second inlet 201. The pressure inside the second container 2 is about 20 kPa (corresponding to a liquid ammonia saturation temperature of about -30°C). The temperature of the medium in the condensation section of the heat exchange tube 4 is higher than the temperature of the second liquid ammonia in the second container 2. The ammonia gas in the condensation section of the heat exchange tube 4 transfers the heat it carries to the second liquid ammonia in the second container 2. After absorbing the heat, the second liquid ammonia evaporates into ammonia gas. After the ammonia gas in the condensation section of the heat exchange tube 4 transfers the heat to the liquid ammonia in the second container 2, the temperature drops rapidly. The ammonia gas condenses into liquid ammonia and returns to the bottom of the heat exchange tube 4 along the inner wall of the heat exchange tube 4, repeating the heat exchange cycle.

[0060] The liquid ammonia in the second container 2 absorbs heat and evaporates into ammonia gas. After passing through the baffle plate 5, it further absorbs heat from the condensation section of the heat exchange tube 4, heating the ammonia gas to 30°C before leaving the liquid ammonia vaporization device through the second outlet 203.

[0061] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A liquid ammonia vaporization device, characterized in that, include: A first container (1) and a second container (2) are provided with a heat-insulating barrier structure (3) between the opposing walls of the first container (1) and the second container (2). The first container (1) is provided with a first inlet (101), a first receiving cavity (102) and a first outlet (103). The first inlet (101) and the first outlet (103) are both connected to the first receiving cavity (102). The second container (2) is provided with a second inlet (201), a second receiving cavity (202) and a second outlet (203). The second inlet (201) and the second outlet (203) are both connected to the second receiving cavity (202). Multiple heat exchange tubes (4) are spaced apart in the first accommodating cavity (102) and the second accommodating cavity (202). The heat exchange tubes (4) pass through the heat insulation barrier structure (3) and are placed in the first accommodating cavity (102) and the second accommodating cavity (202). The heat exchange tubes (4) are suitable for containing the first liquid ammonia, the first accommodating cavity (102) is suitable for containing the heating medium, and the second accommodating cavity (202) is suitable for containing the second liquid ammonia. The pressure of the first liquid ammonia is greater than the pressure of the second liquid ammonia. The first liquid ammonia is vaporized into ammonia gas after exchanging heat with the heating medium. The ammonia gas is liquefied after exchanging heat with the second liquid ammonia gas again. The second liquid ammonia gas is vaporized into ammonia gas and then output through the second outlet (203).

2. The liquid ammonia vaporization device according to claim 1, characterized in that, Multiple heat exchange tubes (4) are arrayed in the first receiving cavity (102) and the second receiving cavity (202).

3. The liquid ammonia vaporization device according to claim 2, characterized in that, A baffle (5) is provided between the two rows of heat exchange tubes (4) near the second outlet (203) in the second receiving cavity (202).

4. The liquid ammonia vaporization device according to claim 3, characterized in that, There are multiple baffles (5), which are staggered along the flow direction of ammonia.

5. The liquid ammonia vaporization device according to claim 1, characterized in that, The thermal insulation barrier structure (3) includes a first partition (301) that is attached to the wall of the first container (1), a second partition (302) that is attached to the wall of the second container (2), and a thermal insulation board (303) disposed between the first partition (301) and the second partition (302).

6. The liquid ammonia vaporization device according to claim 5, characterized in that, Both the first partition (301) and the second partition (302) are metal partitions.

7. The liquid ammonia vaporization apparatus according to any one of claims 1 to 6, characterized in that, The heat exchange tube (4) has fins (6) on its outer wall.

8. The liquid ammonia vaporization device according to claim 7, characterized in that, The fins (6) of the heat exchange tube (4) located in the first receiving cavity (102) are annular fins, and the fins (6) of the heat exchange tube (4) located in the second receiving cavity (202) are serrated fins extending axially parallel to the heat exchange tube (4).

9. The liquid ammonia vaporization apparatus according to any one of claims 1 to 6, characterized in that, The amount of the first liquid ammonia filling is 1 / 4 to 1 / 3 of the volume of the heat exchange tube (4).

10. The liquid ammonia vaporization apparatus according to any one of claims 1 to 6, characterized in that, The heating medium is low-temperature hot water, low-temperature steam, hot air, or low-temperature flue gas.

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