Pre-cooler for ammonia gas production

Abstract

The utility model discloses a precooler for ammonia gas production, which comprises a box body and end covers arranged at the two ends of the box body, the box body is connected with the end covers through tube plates, the box body and the end covers are matched to form a cavity, the tube plates partition the cavity to form a first circulation cavity for carbon dioxide circulation and a second circulation cavity for liquid ammonia circulation, and the first circulation cavity and the second circulation cavity are communicated with each other. Carbon dioxide in the first circulation cavity absorbs heat of liquid ammonia in the second circulation cavity, the liquid ammonia in the second circulation cavity is converted into ammonia gas, when the carbon dioxide flows in the first circulation cavity, heat of the liquid ammonia in the second circulation cavity can be effectively absorbed, the heat energy transfer mode is rapid and efficient, the vaporization process of the liquid ammonia can be accelerated, and the vaporization efficiency of the liquid ammonia is improved. Due to the fact that the carbon dioxide is used as a heat exchange medium, the precooler does not need to use extra energy for heating or cooling, meanwhile, the carbon dioxide is used as natural gas, the influence of the carbon dioxide on the environment is small, and the concept of green production is met.

Description

Technical Field

[0001] The utility model relates to the technical field of ammonia, in particular to a precooler used for ammonia production. Background Art

[0002] Ammonia is an inorganic compound and also a common chemical raw material with the chemical formula NH3. It is a colorless gas with a strong pungent odor. Ammonia water and gaseous ammonia products are mainly used as raw and auxiliary materials for the desulfurization process of environmental protection equipment. The existing technology often uses compressed air method, pyrolysis ammonia water method and catalytic oxidation method. Among them, the pyrolysis ammonia water method is to heat the ammonia water, separate the generated ammonia gas and water vapor through a cooler to obtain ammonia. However, this method has low efficiency in producing ammonia and cannot meet the supply and security needs of large enterprises. It is also easy to cause environmental pollution. Therefore, a device with low environmental pollution and high production efficiency is designed for the production of ammonia. Utility Model Content

[0003] The utility model provides a precooler for ammonia production, which solves the problems of low ammonia production efficiency and environmental impact in the prior art.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] A precooler for ammonia production, comprising

[0006] Box;

[0007] End covers, which are arranged at both ends of the box body and form a cavity with the box body;

[0008] The characteristics are as follows: the box body is connected to the end cover through a tube sheet, and the tube sheet partitions the cavity to form a first flow cavity for the circulation of carbon dioxide and a second flow cavity for the circulation of liquid ammonia. The carbon dioxide in the first flow cavity absorbs heat from the liquid ammonia in the second flow cavity, so that the liquid ammonia in the second flow cavity is converted into ammonia gas. When carbon dioxide flows in the first flow cavity, it can effectively absorb the heat of the liquid ammonia in the second flow cavity. This heat energy transfer method is fast and efficient, which helps to accelerate the vaporization process of liquid ammonia. Since carbon dioxide is used as a heat exchange medium, the precooler does not need to use additional energy for heating or cooling. At the same time, as a naturally occurring gas, the use of carbon dioxide has little impact on the environment and is in line with the concept of green production.

[0009] Furthermore, a mounting hole is provided on the tube sheet, a heat exchange tube is installed between the two tube sheets, the heat exchange tube is inserted into the mounting hole, and the two first flow chambers are connected through the heat exchange tube. The installation of the heat exchange tube makes it more efficient to transfer heat energy from the first flow chamber to the second flow chamber. Liquid ammonia can more fully absorb heat from carbon dioxide in the second flow chamber, which accelerates the vaporization process of liquid ammonia, thereby improving the production efficiency of ammonia. At the same time, the two first flow chambers are connected through the heat exchange tube, so that the flow of carbon dioxide in the entire precooler is more uniform, avoiding the problem of local heat accumulation.

[0010] Furthermore, a partition is provided in the first circulation cavity on one side, which separates the first circulation cavity into an air inlet cavity and an air outlet cavity. The air inlet cavity is specifically used for the entry of carbon dioxide, and enters the first circulation cavity on the other side through the heat exchange tube, while the air outlet cavity is responsible for the discharge of carbon dioxide, so that carbon dioxide flows back to the air outlet cavity from the first circulation cavity on the other side. Such a design avoids air flow chaos, increases the circulation distance of carbon dioxide, and improves heat exchange efficiency.

[0011] Furthermore, a clamping groove is provided on the tube sheet, and a clamping part is provided on the partition, which is installed in the clamping groove. The precise design and manufacture of the clamping groove enables the installation position of the partition to be precisely controlled, thereby avoiding problems such as reduced heat exchange efficiency or leakage due to position deviation. The close fit between the clamping groove and the clamping part makes the connection between the partition and the tube sheet more firm and reliable. This connection method can effectively resist the vibration and impact generated by the precooler during operation, thereby ensuring the long-term stable operation of the precooler.

[0012] Furthermore, a baffle is provided in the second flow cavity, which changes the flow direction and speed of the fluid so that the fluid forms a turbulent state in the heat exchanger to improve the heat exchange effect. The baffle also plays a role in supporting the tube bundle to prevent it from being deformed due to pressure or temperature changes.

[0013] Furthermore, distance tubes are evenly distributed between the tube sheets and the baffles, the main function of which is to maintain a certain distance between the heat exchange tubes to promote the formation of a strong turbulent state of the fluid between the inner tubes, which can make the heat more evenly distributed, thereby improving the heat exchange efficiency.

[0014] Furthermore, the baffle is penetrated by a mounting hole, in which a pull rod is installed, one end of the pull rod is connected to the distance tube, and the pull rod is connected to the distance tube via a nut. The nut connection can ensure that the connection between the pull rod and the distance tube is tight and not easy to loosen, thereby ensuring the stability of the precooler during operation. At the same time, the easy disassembly of the nut connection also facilitates the maintenance and replacement of the baffle, pull rod and distance tube.

[0015] Furthermore, a shell connected to the box body is provided on the box body, and the shell is connected to the box body through a flange. The shell and the box body are connected through a flange. The flange connection has the characteristics of high structural strength and good sealing, which can effectively prevent the precooler from leaking or loosening during operation, which ensures that the precooler can operate stably and reliably under high pressure, high temperature or corrosive environment. Since the flange connection is detachable, there is no need to disassemble the entire precooler when installing and replacing parts, which reduces maintenance costs and downtime.

[0016] Furthermore, a wire mesh filter is provided in the shell, and the wire mesh filter is used to filter the generated ammonia. During the ammonia production process, due to the influence of raw materials and processes, some tiny impurities or particulate matter may be generated. If these impurities flow out with the ammonia, they may cause damage to subsequent production processes or equipment. Therefore, filtering through the wire mesh filter can greatly improve the quality of the ammonia and ensure the smooth progress of production.

[0017] Furthermore, a wound gasket is provided at the connection between the shell and the box body. Since the working environment of the precooler usually involves high pressure, high temperature or corrosive media, the sealing performance of the connection is crucial. The wound gasket can fit tightly on the connection surface to form a reliable sealing barrier to ensure that the medium will not leak from the connection. During the operation of the precooler, the connection may be subject to certain impacts and vibrations due to factors such as medium flow and temperature changes. The elasticity and plasticity of the wound gasket can effectively absorb these impacts and vibrations and protect the stability and safety of the connection.

[0018] The utility model has the following beneficial effects due to the adoption of the above technical solution:

[0019] The utility model discloses a precooler for ammonia production, wherein a box body is connected with an end cover through a tube sheet, and the tube sheet partitions a cavity to form a first circulation cavity for the circulation of carbon dioxide and a second circulation cavity for the circulation of liquid ammonia. The carbon dioxide in the first circulation cavity absorbs heat from the liquid ammonia in the second circulation cavity, so that the liquid ammonia in the second circulation cavity is converted into ammonia. When the carbon dioxide flows in the first circulation cavity, the heat of the liquid ammonia in the second circulation cavity can be effectively absorbed. This heat energy transfer method is fast and efficient, and helps to accelerate the vaporization process of the liquid ammonia. Since the carbon dioxide is used as the heat exchange medium, the precooler does not need to use additional energy for heating or cooling. At the same time, as a naturally occurring gas, the use of carbon dioxide has little impact on the environment, which is in line with the concept of green production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The utility model is further described below in conjunction with the accompanying drawings:

[0021] Figure 1 This is a full cross-sectional front view of a precooler for ammonia production according to the utility model;

[0022] Figure 2 It is a left view of the utility model;

[0023] Figure 3 It is a full cross-sectional view of the end cover of the utility model;

[0024] Figure 4 It is a left side view of the end cover of the utility model;

[0025] Figure 5 This is a schematic diagram of the structure of the partition in the utility model;

[0026] Figure 6 for Figure 5 Partial cross-sectional view along the AA axis;

[0027] Figure 7 This is a structural schematic diagram of the tube plate in the utility model;

[0028] Figure 8 for Figure 7 A partial enlarged view of point B in the middle;

[0029] Fig. 9 It is a structural schematic diagram of the baffle in the utility model;

[0030] Fig.10 It is a structural schematic diagram of the connection between the tube plate and the partition in the utility model;

[0031] Fig.11 It is a structural schematic diagram of the connection between the pull rod and the baffle in the utility model.

[0032] In the figure,

[0033] 10-end cover; 11-housing; 12-second circulation chamber; 13-first circulation chamber; 14-connecting shell; 15-housing; 16-exhaust hole; 17-winding pad; 18-wire mesh filter; 19-drain port; 20-inlet port; 22-spacer tube; 23-heat exchange tube; 24-baffle; 25-tube sheet; 26-inlet port; 27-outlet port; 28-inlet chamber; 29-outlet chamber; 30-saddle; 32-connecting part; 33-exhaust port; 34-connecting hole; 35-partition plate; 36-mounting hole; 37-matching hole; 38-clamping groove; 39-clamping part; 40-seal; 41-pull rod. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0037] like Figures 1 to 11 As shown, this is a precooler for ammonia production of the utility model, the main function of which is to separate the box body 11 and the end cover 10 into a first flow chamber 13 for the flow of carbon dioxide and a second flow chamber 12 for the flow of liquid ammonia through the tube plate 25, and the carbon dioxide in the first flow chamber 13 absorbs heat from the liquid ammonia in the second flow chamber 12, thereby achieving the effect of converting the liquid ammonia in the second flow chamber 12 into ammonia.

[0038] The utility model discloses a precooler for ammonia production, comprising a box body 11 and end covers 10 arranged at both ends of the box body 11, the end covers 10 being connected to the box body 11 through a tube sheet 25, the box body 11 being cylindrical, a connecting portion 32 being arranged at the open end of the box body 11, a connecting hole 34 being arranged on the connecting portion 32, the connecting hole 34 being arranged along the circumference of the connecting portion 32, a matching hole 37 corresponding to the connecting hole 34 being arranged on the tube sheet 25, a bolt passing through the connecting hole 34 and the matching hole 37 being matched with a nut to realize the disassembly and assembly connection of the box body 11 and the end covers 10, the end covers 10 being in the shape of a shell 15, the end covers 10 and the box body 11 being connected to form a cavity, The cavity is divided into two left and right first circulation cavities 13 for the circulation of carbon dioxide and a second circulation cavity 12 for the circulation of liquid ammonia by the tube sheet 25. An air inlet 26 and an air outlet 27 are provided on the end cover 10 on one side, and an exhaust port 33 is provided on the end cover 10 on the other side. There are two exhaust ports 33, which are respectively used to exhaust the gas in the cavity before work. The air inlet 26 is arranged above the air outlet 27. The mass of carbon dioxide molecules is greater than that of air molecules. They will be affected by a greater gravitational force and move downward. The air inlet 26 is used for the entry of carbon dioxide, and the air outlet 27 is used for the exhaust of carbon dioxide after the heat exchange is completed.

[0039] A partition 35 is provided in the first flow cavity 13 of the end cover 10 provided with an air inlet 26, a clamping groove 38 is provided on the tube sheet 25, a sealing member 40 is provided in the clamping groove 38, a clamping portion 39 is provided on the partition 35, the clamping portion 39 is installed in the clamping groove 38 and abuts against the sealing member 40 to achieve the connection between the partition 35 and the tube sheet 25, the partition 35 separates the first flow cavity 13 to form an air inlet cavity 28 and an air outlet cavity 29, the air inlet cavity 28 is communicated with the air inlet 26, the air inlet cavity 28 is specifically used for the entry of carbon dioxide raw material, at which time the temperature of the carbon dioxide is between 25°C and 40°C, and the air outlet cavity 29 is responsible for the discharge of the carbon dioxide after the heat exchange is completed, at which time the temperature of the carbon dioxide is between 0°C and 10°C, and the two gases with different temperatures are isolated by the partition 35 to prevent neutralization from affecting the heat exchange effect.

[0040] The tube sheet 25 is provided with mounting holes 36. The mounting holes 36 on the tube sheets 25 at both ends face each other. The mounting holes 36 are evenly distributed on the surface of the tube sheet 25. The specific number is set according to the actual situation. A heat exchange tube 23 is installed between the two tube sheets 25. The heat exchange tube 23 is inserted into the mounting holes 36. The heat exchange tube 23 and the tube sheet 25 can be connected by welding, or other components can be used to connect the two. The left and right first flow chambers 13 are connected through the heat exchange tube 23. The installation of the heat exchange tube 23 makes it more efficient to transfer heat energy from the first flow chamber 13 to the second flow chamber 12. Liquid ammonia can more fully absorb the dioxygen in the second flow chamber 12. The heat of carbonization accelerates the vaporization process of liquid ammonia, thereby improving the production efficiency of ammonia. At the same time, the two first flow chambers 13 are connected by the heat exchange tube 23, so that the flow of carbon dioxide in the entire precooler is more uniform, avoiding the problem of local heat accumulation. When working, carbon dioxide enters the air inlet chamber 28 from the air inlet 26, enters the heat exchange tube 23 and moves to the first flow chamber 13 on the other side. The carbon dioxide reacts with the liquid ammonia in the box body 11 in the heat exchange tube 23 and absorbs heat. The carbon dioxide moves from the first flow chamber 13 along the heat exchange tube 23 to react again until it reaches the air outlet chamber 29, and is discharged from the precooler through the air outlet chamber 29.

[0041] A saddle 30 is provided on the lower surface of the box body 11, and the saddle 30 is in contact with the installation bottom surface. The setting of the saddle 30 facilitates the installation of the precooler. A liquid inlet 20 and a liquid drain 19 are provided on the lower surface of the box body 11. The liquid inlet 20 is used for the injection of liquid ammonia, and the liquid drain 19 is used to empty the medium in the box body 11 before the precooler works. A connecting shell 14 is formed on the upper surface of the box body 11, and the connecting shell 14 is communicated with the second flow cavity 12. A shell 15 is connected to the connecting shell 14, and the connecting shell 14 and the shell 15 are disassembled and connected through a flange. The flange connection has the characteristics of high structural strength and good sealing, which can effectively prevent the precooler from leaking or loosening during operation. A winding gasket 17 is provided at the connection between the shell 15 and the box body 11. The winding gasket 17 can be tightly fitted on the inner surface of the connection between the connecting shell 14 and the shell 15 to form a reliable sealing barrier to ensure that the medium will not leak from the connection and improve the sealing effect of the connection.

[0042] An exhaust hole 16 is provided on the shell 15, and the exhaust hole 16 is communicated with the second flow cavity 12 in the box body 11. The exhaust hole 16 is the output channel interface of the ammonia after production. A wire mesh filter 18 is installed in the connecting shell 14. The wire mesh filter 18 can be disassembled and connected to the connecting shell 14 by screws or card connections. Other connection methods can be used to achieve the same effect. The wire mesh filter 18 is used to filter the generated ammonia, improve the quality of ammonia, and ensure the smooth progress of production.

[0043] Baffles 24 are arranged in the second flow chamber 12 to form a gap between the baffles 24 and the second flow chamber 12, and liquid ammonia can flow through the gap. The gaps between two adjacent baffles 24 are arranged one above the other, so that when liquid ammonia flows, a turbulent state in the heat exchanger is formed to improve the heat exchange effect. At the same time, the arrangement of the baffles 24 can improve the supporting effect on the box body 11 and improve the supporting strength. The baffles 24 are equipped with spacing tubes 22, and the spacing tubes 22 are evenly arranged. The baffles 24 are penetrated by mounting holes 36, and a pull rod 41 is installed in the mounting hole 36. One end of the pull rod 41 is connected to the spacing tube 22, and the pull rod 41 is connected to the spacing tube 22 through a nut to realize the connection between the spacing tube 22 and the baffle 24.

[0044] The workflow of this utility model is as follows:

[0045] Before work, the medium in the cavity is discharged through the exhaust port 33 and the drain port 19, the exhaust port 33, the drain port 19 and other unnecessary interfaces are closed, and liquid ammonia is injected into the second circulation cavity 12 through the liquid inlet 20. At the same time, the heated carbon dioxide is injected into the air inlet cavity 28 through the air inlet 26. The carbon dioxide enters the heat exchange tube 23 through the mounting hole 36 on the tube plate 25 and is transported to the second circulation cavity 12. At this time, the carbon dioxide gas in the heat exchange tube 23 reacts with the liquid ammonia in the first circulation cavity 13 without direct contact, and the liquid ammonia is converted into ammonia gas. The ammonia gas is filtered by the wire mesh filter 18 arranged in the connecting shell 14, and finally collected and processed through the exhaust port 16. The carbon dioxide enters the heat exchange tube 23 again through the first circulation cavity 13 on the other side, and reacts with the liquid ammonia in the first circulation cavity 13 until it reaches the air outlet cavity 29 and is discharged from the precooler through the exhaust port 33.

[0046] The above are only specific embodiments of the utility model, but the technical features of the utility model are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the utility model to solve basically the same technical problems and achieve basically the same technical effects are all included in the protection scope of the utility model.

Claims

1. A precooler for ammonia production, comprising: Box; End covers, which are arranged at both ends of the box body and form a cavity with the box body; Features: The box body is connected to the end cover through a tube sheet, and the tube sheet partitions the cavity to form a first flow cavity for the flow of carbon dioxide and a second flow cavity for the flow of liquid ammonia. The carbon dioxide in the first flow cavity absorbs heat from the liquid ammonia in the second flow cavity, thereby converting the liquid ammonia in the second flow cavity into ammonia gas.

2. A precooler for ammonia production according to claim 1, characterized in that: The tube sheet is provided with a mounting hole, a heat exchange tube is installed between the two tube sheets, the heat exchange tube is inserted into the mounting hole, and the two first flow chambers are connected through the heat exchange tube.

3. A precooler for ammonia production according to claim 1, characterized in that: A partition is provided in the first flow cavity on one side, and the partition partitions the first flow cavity to form an air inlet cavity and an air outlet cavity.

4. A precooler for ammonia production according to claim 3, characterized in that: The tube plate is provided with a clamping groove, the partition plate is provided with a clamping portion, and the clamping portion is installed in the clamping groove.

5. A precooler for ammonia production according to claim 1, characterized in that: A baffle is provided in the second flow cavity, and the baffle is used to improve the heat exchange effect.

6. A precooler for ammonia production according to claim 5, characterized in that: Distance tubes are evenly distributed between the tube sheet and the baffle.

7. A precooler for ammonia production according to claim 6, characterized in that: The baffle is penetrated by a mounting hole, a pull rod is installed in the mounting hole, one end of the pull rod is connected to the distance tube, and the pull rod is connected to the distance tube through a nut.

8. A precooler for ammonia production according to claim 1, characterized in that: The box body is provided with a shell body communicated with the box body, and the shell body is connected to the box body through a flange.

9. A precooler for ammonia production according to claim 8, characterized in that: A wire mesh filter is arranged in the shell, and the wire mesh filter is used for filtering the generated ammonia gas.

10. A precooler for ammonia production according to claim 8, characterized in that: A winding pad is provided at the connection between the shell and the box body.

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