Hydrogen cyanamide hydrolysis kettle cooling system

Abstract

The utility model relates to a cyanamide hydrolysis kettle cooling system which comprises a reaction kettle, an outer jacket is fixedly connected to the outer wall of the reaction kettle, a closed heat exchange cavity is formed between the outer jacket and the reaction kettle, a medium input pipe is arranged at the bottom of the heat exchange cavity, and a medium output pipe is arranged at the top of the heat exchange cavity; two first partition plates distributed up and down are fixedly connected into the cooling box, an inner cavity of the cooling box is divided into a cooling chamber, a filtering chamber and a water storage chamber from top to bottom in sequence through the two first partition plates, the cooling chamber is provided with a circulation input pipe, the medium output pipe is communicated with the circulation input pipe through a first water pump, and the water storage chamber is provided with a circulation output pipe; the medium input pipe is communicated with the circulating output pipe through a second water pump. The cooling medium exchanges heat with the reaction solution in the heat exchange cavity, enters the cooling box through the first water pump to be cooled, and then is conveyed into the heat exchange cavity again through the second water pump to exchange heat to form circulating heat exchange cooling, so that the cooling requirement in the cyanamide production process is met.

Description

Technical Field

[0001] This utility model relates to the field of cooling technology in cyanamide production, specifically to a cooling system for a cyanamide hydrolysis reactor. Background Technology

[0002] Monocyanamide, scientifically known as aminocyanide, is used in pesticides, pharmaceutical intermediates, and cyanuramide. In other countries, monocyanamide solution is used as a defoliant for fruits and trees and as a non-toxic insecticide. Monocyanamide production involves adding calcium cyanamide and water to a hydrolysis reactor for a hydrolysis reaction, while simultaneously introducing carbon dioxide for a calcification reaction, thus obtaining a monocyanamide solution. Throughout the hydrolysis process, the reaction temperature must be controlled to not exceed 30°C. Traditional monocyanamide hydrolysis reactors use a dedicated refrigeration system to cool the liquid before it is transported to the reactor, which is energy-intensive and costly.

[0003] Patent CN205204839U discloses a cooling system device for a cyanamide hydrolysis reactor. Its main principle is to use the process of introducing carbon dioxide into the hydrolysis reactor. The liquid carbon dioxide enters the heat exchange coil, vaporizes and absorbs heat, and takes away the heat in the cooling water pool, thereby cooling the coolant in the cooling water pool and saving energy. Then, the coolant is introduced into the cooling coil on the hydrolysis reactor to exchange heat with the reaction solution and absorb heat, thereby achieving cooling.

[0004] In cyanamide production, only a small amount of carbon dioxide is typically introduced into the hydrolysis reactor for calcification. Therefore, the liquid carbon dioxide storage tank only needs to release a small amount of carbon dioxide to participate in the reaction; continuous release would result in a significant waste of liquid carbon dioxide. In other words, the vaporization process of liquid carbon dioxide in the heat exchange coil is brief. When the carbon dioxide supply stops, it can no longer cool the coolant. Therefore, the heat absorption process is relatively short, resulting in limited heat absorption and insufficient cooling of the reaction solution for the hydrolysis reaction, failing to meet the heat exchange and cooling requirements of the reaction solution. Furthermore, this patented technology lacks filtration throughout the entire heat exchange and cooling process, which can easily lead to impurity accumulation and pipe blockage over prolonged use. Utility Model Content

[0005] This invention addresses the shortcomings of existing technologies by providing a cooling system for a cyanamide hydrolysis reactor. The system offers a stable cooling process, higher cooling efficiency, and the ability to filter impurities during cooling, thus meeting the cooling requirements of the cyanamide production process.

[0006] This utility model is achieved through the following technical solution: a cooling system for a cyanamide hydrolysis reactor, comprising a reactor, an outer jacket fixedly connected to the outer wall of the reactor, forming a sealed heat exchange cavity between the outer jacket and the reactor, a medium input pipe at the bottom of the heat exchange cavity, and a medium output pipe at the top of the heat exchange cavity; it also includes a cooling box, with two vertically distributed first partitions fixedly connected inside the cooling box, the inner cavity of the cooling box being divided by the two first partitions to form a cooling chamber, a filtration chamber, and a water storage chamber from top to bottom, the cooling chamber, the filtration chamber, and the water storage chamber being sequentially connected, the cooling chamber being provided with a circulation input pipe, the medium output pipe being connected to the circulation input pipe through a first water pump, the water storage chamber being provided with a circulation output pipe, and the medium input pipe being connected to the circulation output pipe through a second water pump.

[0007] In this scheme, the cooling medium exchanges heat with the reaction solution in the heat exchange cavity, thereby cooling the reaction solution. The heated cooling medium is pumped into the cooling tank by the first water pump, and then passes through the cooling chamber for further cooling. After impurities are filtered out in the filtration chamber, it enters the water storage chamber and is pumped back into the heat exchange cavity by the second water pump to exchange heat with the reaction solution, forming a circulating heat exchange cooling process. The cooling process is stable and has higher cooling efficiency. However, the cooling process can filter impurities to avoid clogging the pipeline, thus meeting the cooling requirements of the cyanamide production process.

[0008] As an optimization, the outer jacket is wrapped with an insulation layer. This optimization uses the insulation layer to retain heat, reducing heat exchange between the cooling medium and the outside air, and further improving the cooling effect.

[0009] As an optimization, multiple heat-conducting blocks are evenly distributed circumferentially on the outer wall of the reactor within the heat exchange cavity. This optimization accelerates the transfer of heat from the reactor to the heat exchange cavity via these heat-conducting blocks, further improving cooling efficiency.

[0010] As an optimization, a first drain pipe connecting the cooling chamber and the filter chamber is fixedly connected to the upper first partition, and a second drain pipe connecting the filter chamber and the water storage chamber is fixedly connected to the lower first partition. Valves are installed on both the first and second drain pipes. The chambers are sequentially connected through the first and second drain pipes, and the discharge is controlled by the valves, making it convenient to use.

[0011] As an optimization, a second partition is fixedly connected to the cooling chamber, dividing the cooling chamber into a primary cooling chamber and a secondary cooling chamber distributed to the left and right. The second partition has an overflow port connecting the primary and secondary cooling chambers. A heat-conducting coil is installed in the primary cooling chamber, and a cooler is connected to the outside of the heat-conducting coil. A cooling fan is installed in the secondary cooling chamber. This optimization improves the cooling efficiency of the cooling medium by cooling it through two stages of cooling water chambers.

[0012] As an optimization, temperature sensors are installed in both the primary and secondary cooling chambers. This optimization facilitates the control of the cooling temperature.

[0013] As an optimization, the filtration chamber is equipped with a vertically distributed sand and gravel filter layer and an activated carbon filter layer. This optimization uses the sand and gravel filter layer to filter large particulate impurities and the activated carbon filter layer to filter small particulate impurities, ensuring filtration efficiency.

[0014] The beneficial effects of this invention are as follows: the cooling medium exchanges heat with the reaction solution in the heat exchange cavity, thereby cooling the reaction solution. The cooling medium, which has been heated by the heat exchange, enters the cooling tank through the first water pump to cool down, and then passes through the cooling chamber for further cooling. After filtering impurities in the filtration chamber, it enters the water storage chamber and is then pumped back to the heat exchange cavity by the second water pump to exchange heat with the reaction solution, forming a circulating heat exchange cooling process. The cooling process is stable and the cooling efficiency is higher. Furthermore, the cooling process can filter impurities, avoiding pipe blockage and meeting the cooling requirements of the cyanamide production process. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the reactor structure;

[0017] As shown in the figure:

[0018] 1. Reactor; 11. Water inlet; 12. Feed inlet; 13. Vent; 14. Discharge outlet; 15. Motor; 16. Stirring rod; 17. Rotary shaft; 18. First water pump; 19. Second water pump.

[0019] 2. Outer jacket; 20. Heat exchange cavity; 21. Medium inlet pipe; 22. Medium outlet pipe;

[0020] 3. Insulation layer; 4. Heat-conducting block;

[0021] 5. Cooling tank; 51. Circulation input pipe; 52. Circulation output pipe; 53. Medium inlet pipe;

[0022] 6. First partition; 61. First drain pipe; 62. Second drain pipe;

[0023] 7. Cooling chamber; 71. Primary cooling chamber; 72. Secondary cooling chamber; 73. Second partition; 74. Overflow port; 75. Heat transfer coil; 76. Cooler; 77. Cooling fan; 78. Temperature sensor.

[0024] 8. Filter chamber; 81. Sand and gravel filter layer; 82. Activated carbon filter layer;

[0025] 9. Water storage room. Detailed Implementation

[0026] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to describe the solution.

[0027] like Figures 1-2 As shown, a cyanamide hydrolysis reactor cooling system includes a reactor 1. The reactor 1 has a water inlet 11, a vent 13, and a feed inlet 12 at its top, and a discharge outlet 14 at its bottom, with a valve installed on the outlet 14. A stirring mechanism is installed inside the reactor 1, including a rotating shaft 17 rotatably connected to the top of the reactor 1. A motor 15 is fixed to the top of the reactor 1 to drive the rotating shaft 17, and a stirring rod 16 is fixed to the outer wall of the rotating shaft 17. Water is added to the reactor 1 through the water inlet 11, calcium cyanamide raw material is added through the feed inlet 12, and carbon dioxide gas is introduced through the vent 13. Through the hydrolysis reaction of calcium cyanamide and the calcification reaction of carbon dioxide, cyanamide solution is produced. The produced cyanamide solution is discharged from the discharge outlet 14 for further processing.

[0028] An outer jacket 2 is fixed to the outer wall of the reactor 1, forming a sealed heat exchange cavity 20 between the outer jacket 2 and the reactor 1. A medium inlet pipe 21 is located at the bottom of the heat exchange cavity 20, and a medium outlet pipe 22 is located at the top of the heat exchange cavity 20. Both the medium inlet pipe 21 and the medium outlet pipe 22 are connected to the heat exchange cavity 20. Valves are installed on both the medium inlet pipe 21 and the medium outlet pipe 22 to facilitate control of the medium's entry and exit. Cooling medium is introduced into the heat exchange cavity 20 through the medium inlet pipe 21, gradually filling the cavity from bottom to top before exiting through the medium outlet pipe 22. The bottom-entry cooling medium ensures that it fills the entire heat exchange cavity, effectively enveloping the entire outer wall of the reactor 1 for cooling, resulting in better heat exchange performance.

[0029] Preferably, the outer wall of the reactor 1 located within the heat exchange cavity 20 has multiple heat-conducting blocks 4 evenly distributed circumferentially. These heat-conducting blocks 4 accelerate the transfer of heat from the reactor 1 to the heat exchange cavity 20 for heat exchange, thereby improving cooling efficiency.

[0030] Preferably, the outer jacket 2 is wrapped with an insulation layer 3. The insulation layer 3 provides insulation, reducing heat exchange between the cooling medium and the outside air, and further improving the cooling effect.

[0031] It also includes a cooling box 5, inside which are fixed two vertically distributed first partitions 6. In this embodiment, the first partitions 6 are horizontally arranged. The inner cavity of the cooling box 5 is divided by the two first partitions 6 to form a cooling chamber 7, a filter chamber 8 and a water storage chamber 9 from top to bottom. The cooling chamber 7, the filter chamber 8 and the water storage chamber 9 are connected in sequence. A circulation input pipe 51 is provided on the cooling chamber 7. The medium output pipe 22 is connected to the circulation input pipe 51 through a first water pump 18. A circulation output pipe 52 is provided on the water storage chamber 9. The medium input pipe 21 is connected to the circulation output pipe 52 through a second water pump 19.

[0032] After the cooling medium is heated in the heat exchange cavity 20, it is sent to the cooling tank 5 for cooling by the first water pump 18. The cooling medium is then cooled by passing through the cooling chamber 7 and filtered for impurities by the filter chamber 8 before entering the water storage chamber 9 for storage. The cooled medium is then sent back to the heat exchange cavity 20 by the second water pump 19 to form a cooling cycle. The cooling process is stable and has higher cooling efficiency. The cooling process can filter impurities and avoid clogging the pipeline, thus meeting the cooling requirements of the cyanamide production process.

[0033] Specifically, a first drain pipe 61, connecting the cooling chamber 7 and the filter chamber 8, is fixedly connected to the upper first partition 6, and a second drain pipe 62, connecting the filter chamber 8 and the water storage chamber 9, is fixedly connected to the lower first partition 6. Valves are installed on both the first drain pipe 61 and the second drain pipe 62. The cooling chamber, filter chamber, and water storage chamber are sequentially connected through the first and second drain pipes, and the discharge of the cooling medium is controlled by the valves, making it convenient to use.

[0034] Preferably, a second partition 73 is fixedly connected inside the cooling chamber 7. In this embodiment, the second partition 73 is vertically arranged. The cooling chamber 7 is divided by the second partition 73 into a primary cooling chamber 71 and a secondary cooling chamber 72 distributed to the left and right. The second partition 73 is provided with an overflow port 74 connecting the primary cooling chamber 71 and the secondary cooling chamber 72. A heat-conducting coil 75 is provided inside the primary cooling chamber 71, and a cooler 76 is connected to the outside of the heat-conducting coil 75. A cooling fan 77 is provided on the secondary cooling chamber 72. In this embodiment, both the cooler 76 and the cooling fan 77 are installed on the top of the cooling box 5. The circulation input pipe 51 is connected to the primary cooling chamber 71, and the first drain pipe 61 is connected to the secondary cooling chamber 72. In this embodiment, a medium inlet pipe 53 is provided on the secondary cooling chamber 72, and a valve is installed on the medium inlet pipe 53 to replenish the cooling medium into the cooling box 5.

[0035] After heat exchange, the cooling medium first enters the primary cooling chamber 71 through the circulation input pipe 51 for initial cooling. The heat is then transferred to the cooler 76 via the heat-conducting coil 75, achieving primary cooling. The cooled medium from the primary cooling stage then enters the secondary cooling chamber 72 through the overflow port 74, where it is further cooled by the cooling fan 77, achieving secondary cooling. This two-stage cooling process improves the cooling efficiency of the cooling medium.

[0036] Preferably, both the primary cooling chamber 71 and the secondary cooling chamber 72 are equipped with temperature sensors 78. These two temperature sensors can respectively sense the medium temperature in the two cooling chambers, facilitating manual control and adjustment of the cooling temperature.

[0037] Specifically, the filter chamber 8 is equipped with a sand and gravel filter layer 81 and an activated carbon filter layer 82 distributed vertically. The cooling medium discharged from the first drain pipe 61 first passes through the sand and gravel filter layer 81 to filter out large particulate impurities, and then passes through the activated carbon filter layer 82 to filter out small particulate impurities, ensuring the filtration effect.

[0038] Working principle: Cooling medium is added to the cooling tank 5 through the medium inlet pipe 53. The cooling medium enters the filter chamber 8 through the first drain pipe 61 to filter impurities, and then enters the water storage chamber 9 through the second drain pipe 62. The cooling medium is sent into the heat exchange cavity 20 for heat exchange by the second water pump 19. After heat exchange, the cooling medium re-enters the cooling chamber 7 through the first water pump 18 to cool down and form a cooling cycle.

[0039] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A cooling system for a monomethyl amine hydrolysis reactor comprising a reactor vessel (1) characterised in that: The outer wall of the reaction kettle (1) is fixed with an outer jacket (2), and the outer jacket (2) and the reaction kettle (1) form a closed heat exchange cavity (20), the bottom of the heat exchange cavity (20) is provided with a medium input pipe (21), and the top of the heat exchange cavity is provided with a medium output pipe (22); The cooling box (5) is further provided with two first partitions (6) fixedly connected in the cooling box (5), the inner cavity of the cooling box (5) is divided into a cooling chamber (7), a filtering chamber (8) and a water storage chamber (9) from top to bottom by the two first partitions (6), the cooling chamber, the filtering chamber and the water storage chamber are sequentially communicated, the cooling chamber (7) is provided with a circulating input pipe (51), the medium output pipe (22) is communicated with the circulating input pipe (51) through a first water pump (18), and the water storage chamber (9) is provided with a circulating output pipe (52), and the medium input pipe (21) is communicated with the circulating output pipe (52) through a second water pump (19).

2. The monosolvane hydrolysis still cooling system of claim 1, wherein: The outer jacket (2) is wrapped with a heat preservation layer (3) outside.

3. The monosolvane hydrolysis still cooling system of claim 1, wherein: The reaction kettle (1) is located in the heat exchange cavity (20) and is uniformly distributed with a plurality of heat conducting blocks (4) on the outer wall in the circumferential direction.

4. The monosolvane hydrolysis still cooling system of claim 1, wherein: The first partition (6) located at the upper portion is fixedly connected with a first drain pipe (61) communicating the cooling chamber (7) and the filtering chamber (8), and the first partition (6) located at the lower portion is fixedly connected with a second drain pipe (62) communicating the filtering chamber (8) and the water storage chamber (9), and the first drain pipe and the second drain pipe are both provided with valves.

5. The monosolvane hydrolysis still cooling system of claim 1, wherein: The cooling chamber (7) is fixedly connected with a second partition (73), and the cooling chamber (7) is divided into a first cooling cavity (71) and a second cooling cavity (72) distributed on the left and right sides by the second partition (73), the second partition (73) is provided with an overflow port (74) communicating the first cooling cavity (71) and the second cooling cavity (72), the first cooling cavity (71) is provided with a heat conducting coil pipe (75), the heat conducting coil pipe (75) is connected with a cooler (76), and the second cooling cavity (72) is provided with a cooling fan (77).

6. The monosolvane hydrolysis still cooling system of claim 5, wherein: The first cooling cavity (71) and the second cooling cavity (72) are both provided with temperature sensors (78).

7. The monosolvane hydrolysis still cooling system of claim 1, wherein: The filtering chamber (8) is provided with a sand filtering layer (81) and an activated carbon filtering layer (82) distributed in the upper and lower portions.

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