Ammonia synthesis tower
By setting up a heat exchange tube in the ammonia synthesis tower to recover the heat of the ammonia synthesis reaction, the problem of heat energy waste in the industrial ammonia synthesis process is solved, and efficient heat energy recovery and reaction rate improvement is achieved.
Patent Information
- Application Number
- CN202422378635.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-09-28
- Filing Date
- 2024-09-29
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-09-29
AI Technical Summary
There is a problem of heat energy waste in the existing industrial synthesis process.
A heat exchange tube in the gap space between the inner cylinder, outer cylinder and the catalyst bed is arranged in the ammonia synthesis tower. The first raw gas is used to take away the heat released from the ammonia synthesis reaction, and the heat energy is recovered and utilized in the catalyst bed.
A high-temperature environment for the ammonia synthesis reaction process is realized, heat energy is avoided, and the activation energy of the reaction is reduced through the catalyst bed, so that the reaction energy is carried out at a significant rate.
Smart Images
Figure CN223113019U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of ammonia synthesis, in particular to an ammonia synthesis tower. Background Art
[0002] Industrial ammonia synthesis is carried out in an ammonia synthesis tower. Ammonia is synthesized from a nitrogen-hydrogen mixture under high temperature (about 390 °C) and the action of a catalyst. The synthesis of ammonia is a strongly exothermic reaction. In current industry, the heat generated by ammonia synthesis is usually taken away by an air-cooling system and dissipated into the atmosphere.
[0003] The prior art has the problem of energy (heat energy) waste. Therefore, the utility model proposes an ammonia synthesis tower that can recycle the heat energy released by the ammonia synthesis reaction. Summary of the Utility Model
[0004] The utility model aims to provide an ammonia synthesis tower to solve the problem of heat energy waste in the existing ammonia synthesis process.
[0005] The technical solution adopted by the utility model is as follows:
[0006] An ammonia synthesis tower, comprising:
[0007] An inner cylinder, the upper side portion of which has air outlet holes;
[0008] An outer cylinder, sleeved outside the inner cylinder, a gap space is formed between the inner cylinder and the outer cylinder, and a catalyst bed is arranged in the gap space;
[0009] And
[0010] Heat exchange tubes, located in the gap space and passing through the catalyst bed;
[0011] Wherein,
[0012] The lower end of the heat exchange tube is communicated with the lower side portion of the inner cylinder;
[0013] The upper side portion of the inner cylinder is communicated with the gap space through the air outlet holes.
[0014] Preferably, the catalyst bed includes a first-stage catalyst bed and a second-stage catalyst bed. The first-stage catalyst bed is located on the upper side of the gap space, and the second-stage catalyst bed is located on the lower side of the gap space.
[0015] Preferably, the first-stage catalyst bed and the second-stage catalyst bed are adjacent to each other.
[0016] Preferably, the heat exchange tubes include straight pipe sections and spiral pipe sections;
[0017] The straight pipe sections and the spiral pipe sections are adjacent to each other;
[0018] Among them,
[0019] The straight pipe section is located in the first catalyst bed layer, and the spiral pipe section is located in the second catalyst bed layer.
[0020] Preferably, it further includes:
[0021] An adiabatic layer;
[0022] The adiabatic layer is arranged on the outer wall of the inner cylinder, thereby isolating the inner cylinder from the catalyst bed layer.
[0023] Preferably, the adiabatic layer is laid along the axial direction of the inner cylinder, and the laying height is not less than the filling height of the catalyst bed layer.
[0024] Preferably, it further includes:
[0025] A heater;
[0026] The heating part of the heater is arranged in the inner cylinder, and the heating part extends along the axial direction of the inner cylinder to heat the mixed gas flowing through the inner cylinder under specific conditions.
[0027] Preferably, it further includes:
[0028] An upper tube sheet;
[0029] The upper tube sheet is arranged at the upper end of the outer cylinder to block the upper part of the gap space. A central hole is also opened at the center position of the upper tube sheet, and the upper end of the inner cylinder penetrates into the central hole;
[0030] A first air inlet for the first raw material gas is opened on the upper tube sheet. Through this first air inlet, the first raw material gas can be introduced into the heat exchange tube.
[0031] Preferably, it further includes:
[0032] A tube sheet cover;
[0033] The tube sheet cover is arranged at the upper end of the upper tube sheet to block the upper end of the inner cylinder;
[0034] The heater is arranged at the upper end of the tube sheet cover, and the heating part of the heater passes through the tube sheet cover and the upper tube sheet and extends downward to the inner cylinder.
[0035] Preferably, it further includes:
[0036] A lower tube sheet;
[0037] The lower tube sheet is arranged at the lower end of the outer cylinder to block the gap space and the lower part of the inner cylinder;
[0038] A second air inlet for the second stream of raw gas is formed in the lower tube sheet. By means of this second air inlet, the second stream of raw gas can be introduced into the inner cylinder.
[0039] A reformed gas outlet for sending out the reformed gas is further formed in the lower tube sheet, and the reformed gas outlet is communicated with the lower end of the gap space.
[0040] The beneficial effects of the utility model are as follows:
[0041] By arranging heat exchange tubes in the catalyst bed of the ammonia synthesis tower, the heat released by the ammonia synthesis reaction stays in the catalyst bed. When the first stream of raw gas flows through the heat exchange tubes, the heat released by the ammonia synthesis reaction can be taken away, so as to obtain a high-temperature gas after heating and temperature rise. Therefore, not only can the reaction process of ammonia synthesis be directly in a high-temperature environment, but also the recovery and utilization of heat energy are realized, effectively avoiding the waste of heat energy. BRIEF DESCRIPTION OF THE DRAWINGS
[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0043] Figure 1 It is a schematic structural diagram of the utility model.
[0044] Reference numerals:
[0045] 10, inner cylinder; 12, air outlet hole;
[0046] 20, outer cylinder;
[0047] 30, catalyst bed; 31, first-stage catalyst bed; 32, second-stage catalyst bed;
[0048] 40, heat exchange tube; 41, straight tube section; 42, spiral tube section;
[0049] 50, heat insulation layer;
[0050] 60, heater; 61, heating part;
[0051] 70, upper tube sheet; 71, first air inlet; 72, central hole;
[0052] 80, lower tube sheet; 81, second air inlet; 82, reformed gas outlet;
[0053] 90, tube sheet cover;
[0054] SP1, clearance space; FG1, first feed gas; FG2, second feed gas; FG3, mixed gas; CG1, converted gas. Detailed implementation mode
[0055] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", "axial", "radial", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.
[0056] The following disclosure provides many different embodiments or examples for implementing different structures of the present utility model. To simplify the disclosure of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present utility model.
[0057] The embodiments of the utility model will be described in detail below with reference to the drawings.
[0058] As Figure 1 shown, the present utility model provides an ammonia synthesis tower, comprising:
[0059] An inner cylinder 10, the upper side portion of which has air outlet holes 12;
[0060] An outer cylinder 20, sleeved outside the inner cylinder 10, a clearance space SP1 is formed between the inner cylinder 10 and the outer cylinder 20, and a catalyst bed 30 is arranged in the clearance space SP1;
[0061] And
[0062] Heat exchange tubes 40, located in the clearance space SP1 and passing through the catalyst bed 30;
[0063] Wherein,
[0064] The lower ends of the heat exchange tubes 40 are communicated with the lower side portion of the inner cylinder 10;
[0065] The upper side portion of the inner cylinder 10 is communicated with the clearance space SP1 by means of the air outlet holes 12.
[0066] Specifically, a plurality of air outlet holes 12 can be provided, and the plurality of air outlet holes 12 are radially uniformly distributed on the upper side of the inner cylinder 10 to accelerate the flow rate of the mixed gas FG3 into the clearance space SP1.
[0067] When in use, the first raw gas FG1 can take away the heat released from the ammonia synthesis reaction when flowing through the heat exchange tube 40 to obtain a high-temperature gas after heating. The heat exchange tube 40 leads the high-temperature gas to the bottom space of the gap space SP1, and mixes it with the second raw gas FG2 also led to the bottom space of the gap space SP1 to obtain a mixed gas FG3. The mixed gas FG3 flows from bottom to top in the inner tube 10, rises to the top of the gap space SP1, and then is led out from the gas outlet 12 on the upper side of the inner tube 10 to the upper part of the catalyst bed 30. The mixed gas FG3 undergoes an ammonia synthesis reaction under the action of the catalyst bed 30, and the heat released by the reaction is removed by the first raw gas FG1 in the heat exchange tube 40 buried in the catalyst bed 30, so that the reaction can continue. Such a cycle not only realizes the recovery and utilization of heat energy and prevents the waste of heat energy, but also makes the reaction process of ammonia synthesis directly in a high-temperature environment, avoiding heating from the beginning to reach the temperature required for the reaction during the reaction process.
[0068] Since the activation energy of the ammonia synthesis reaction is very high, when there is no catalyst, the reaction hardly occurs, and industrial production of ammonia is impossible. The utility model changes the reaction process through the catalyst bed 30, reduces the activation energy of the reaction, and enables the reaction to proceed at a significant rate.
[0069] Specifically, the catalyst bed 30 includes a first-stage catalyst bed 31 and a second-stage catalyst bed 32 . The first-stage catalyst bed 31 is located at the upper side of the gap space SP1 , and the second-stage catalyst bed 32 is located at the lower side of the gap space SP1 .
[0070] In order to ensure that the mixed gas FG3 is always under the action of the catalyst, the first-stage catalyst bed 31 and the second-stage catalyst bed 32 are adjacent to each other.
[0071] Specifically, the heat exchange tube 40 includes a straight tube section 41 and a spiral tube section 42;
[0072] The straight pipe section 41 and the spiral pipe section 42 are adjacent to each other, so that the first raw gas FG1 can flow in the heat exchange tube 40 without hindrance;
[0073] in,
[0074] The straight pipe section 41 is located in the first stage catalyst bed 31 , and the spiral pipe section 42 is located in the second stage catalyst bed 32 .
[0075] The spiral pipe section 42 can ensure that the first raw gas FG1 can be fully heat exchanged.
[0076] During the reaction, along the flow direction of the mixed gas FG3 in the first catalyst bed 31, the temperature of the first catalyst bed 31 continuously rises. When it rises to about 460°C - 470°C, the ammonia synthesis reaction basically does not occur at this temperature. At this time, the first feed gas FG1 in the straight pipe section 41 exchanges heat with the first catalyst bed 31 to remove the heat released by the ammonia synthesis reaction on the first catalyst bed 31; the first feed gas FG1 enters the second catalyst bed 32 and is further heated while removing the heat released by the ammonia synthesis reaction.
[0077] To prevent the heat released by the ammonia synthesis reaction from being lost through the inner cylinder 10 and affecting heat exchange, it further includes:
[0078] An insulating layer 50;
[0079] The insulating layer 50 is arranged on the outer wall of the inner cylinder 10 to isolate the inner cylinder 10 from the catalyst bed 30.
[0080] Specifically, the insulating layer 50 is laid along the axial direction of the inner cylinder 10, and the laying height is not less than the filling height of the catalyst bed 30 to prevent the heat released by the ammonia synthesis reaction from flowing into the inner cylinder 10.
[0081] Furthermore, it further includes:
[0082] A heater 60;
[0083] The heating part 61 of the heater 60 is arranged in the inner cylinder 10, and the heating part 61 extends along the axial direction of the inner cylinder 10 to heat the mixed gas FG3 flowing through the inner cylinder 10 in a specific situation.
[0084] During use, the temperature of the mixed gas FG3 flowing through the inner cylinder 10 is about 320°C - 360°C. When the temperature of the mixed gas FG3 is too low due to reasons and is not sufficient to make the ammonia synthesis reaction proceed at a significant rate, the mixed gas FG3 can be heated and temperature - raised through the heating part 61 when it flows through the inner cylinder 10 to reach the optimal reaction temperature for ammonia synthesis.
[0085] To ensure the sealed environment of the gap space SP1, it further includes:
[0086] An upper tube sheet 70;
[0087] The upper tube sheet 70 is arranged at the upper end of the outer cylinder 20 to block the upper part of the gap space SP1. A central hole 72 is also opened at the central position of the upper tube sheet 70, and the upper end of the inner cylinder 10 penetrates into the central hole 72;
[0088] A first gas inlet 71 for introducing the first feed gas FG1 is formed in the upper tube sheet 70. By means of this first gas inlet 71, the first feed gas FG1 can be introduced into the heat exchange tubes 40.
[0089] Meanwhile, in order to ensure the sealing environment of the inner cylinder 10, it further includes:
[0090] A tube sheet cover 90;
[0091] The tube sheet cover 90 is arranged at the upper end of the upper tube sheet 70 to block the upper end of the inner cylinder 10;
[0092] The heater 60 is arranged at the upper end of the tube sheet cover 90. The heating part 61 of the heater 60 passes through the tube sheet cover 90 and the upper tube sheet 70 and extends towards the lower end of the inner cylinder 10 so as to fully heat the mixed gas FG3.
[0093] Furthermore, it further includes:
[0094] A lower tube sheet 80;
[0095] The lower tube sheet 80 is arranged at the lower end of the outer cylinder 20 to block the gap space SP1 and the lower part of the inner cylinder 10;
[0096] A second gas inlet 81 for introducing the second feed gas FG2 is formed in the lower tube sheet 80. By means of this second gas inlet 81, the second feed gas FG2 can be introduced into the inner cylinder 10;
[0097] A reformed gas outlet 82 for sending out the reformed gas CG1 is also formed in the lower tube sheet 80. The reformed gas outlet 82 is communicated with the lower end of the gap space SP1.
[0098] During use, the mixed gas FG3 undergoes an ammonia synthesis reaction under the action of a high-temperature environment and the catalyst bed 30, generating heat and the reformed gas CG1 at the same time. The reformed gas CG1 flows downward in the gap space SP1 and is sent out through the reformed gas outlet 82.
[0099] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. An ammonia synthesis tower, characterized in that, Comprising: An inner cylinder (10), the upper side portion of which has air outlet holes (12); An outer cylinder (20) sleeved outside the inner cylinder (10), a gap space (SP1) being formed between the inner cylinder (10) and the outer cylinder (20), and a catalyst bed (30) being arranged in the gap space (SP1); And Heat exchange tubes (40) located in the gap space (SP1) and passing through the catalyst bed (30); Wherein, The lower end of the heat exchange tube (40) is communicated with the lower side portion of the inner cylinder (10); The upper side portion of the inner cylinder (10) is communicated with the gap space (SP1) by means of the air outlet holes (12).
2. The ammonia synthesis tower according to claim 1, characterized in that: The catalyst bed (30) includes a first-stage catalyst bed (31) and a second-stage catalyst bed (32), the first-stage catalyst bed (31) being located on the upper side of the gap space (SP1), and the second-stage catalyst bed (32) being located on the lower side of the gap space (SP1).
3. The ammonia synthesis tower according to claim 2, wherein The first-stage catalyst bed (31) and the second-stage catalyst bed (32) are adjacent to each other.
4. The ammonia synthesis tower according to claim 2, characterized in that: The heat exchange tube (40) includes a straight tube section (41) and a spiral tube section (42); The straight tube section (41) and the spiral tube section (42) are adjacent to each other; Wherein, The straight tube section (41) is located in the first-stage catalyst bed (31), and the spiral tube section (42) is located in the second-stage catalyst bed (32).
5. The ammonia synthesis tower according to claim 1, characterized in that, Further comprising: A heat insulation layer (50); The heat insulation layer (50) is arranged on the outer wall of the inner cylinder (10) to isolate the inner cylinder (10) from the catalyst bed (30).
6. The ammonia synthesis tower according to claim 5, characterized in that, The heat insulation layer (50) is laid along the axial direction of the inner cylinder (10), and the laying height thereof is not less than the filling height of the catalyst bed (30).
7. The ammonia synthesis tower according to claim 1, characterized in that, Further comprising: A heater (60); The heating part (61) of the heater (60) is arranged in the inner cylinder (10), and the heating part (61) extends along the axial direction of the inner cylinder (10) to heat the mixed gas (FG3) flowing through the inner cylinder (10) under specific conditions.
8. The ammonia synthesis tower according to claim 7, characterized in that, Further comprising: An upper tube sheet (70); The upper tube sheet (70) is arranged at the upper end of the outer cylinder (20) to block the upper end portion of the gap space (SP1), and a central hole (72) is further opened at the central position of the upper tube sheet (70), and the upper end of the inner cylinder (10) penetrates into the central hole (72); A first air inlet (71) for the first raw material gas (FG1) to enter is opened on the upper tube sheet (70), and by means of the first air inlet (71), the first raw material gas (FG1) can be introduced into the heat exchange tube (40).
9. The ammonia synthesis tower according to claim 8, wherein, Further comprising: A tube sheet cover (90); The tube sheet cover (90) is arranged at the upper end of the upper tube sheet (70) to block the upper end of the inner cylinder (10). The heater (60) is provided at the upper end of the tube sheet cover (90), and the heating portion (61) of the heater (60) passes through the tube sheet cover (90) and the upper tube sheet (70) and extends towards the lower end of the inner cylinder (10).
10. The ammonia synthesis tower according to claim 8, characterized in that, It further includes: a lower tube sheet (80); The lower tube sheet (80) is provided at the lower end of the outer cylinder (20) to block the gap space (SP1) and the lower end portion of the inner cylinder (10); A second air inlet (81) for the second raw material gas (FG2) to enter is formed on the lower tube sheet (80). By means of this second air inlet (81), the second raw material gas (FG2) can be introduced into the inner cylinder (10); A reformed gas outlet (82) for sending out the reformed gas (CG1) is further formed on the lower tube sheet (80), and the reformed gas outlet (82) is communicated with the lower end of the gap space (SP1).