A reactor for urea production

Abstract

The utility model discloses a reaction kettle for urea production belongs to reaction kettle technical field, it includes the shaking frame, the inside center place of shaking frame is equipped with the reaction structure, the reaction structure is the oblique setting, the reaction structure upper end surface center rear is equipped with the pressure -relief structure, the reaction structure inboard wall is equipped with the heating structure, in addition, the utility model discloses, through the stirring rod of servo motor drive, can break the concentration gradient and temperature gradient of material actively, realizes high -efficient agitation to the material in the upper portion of reaction kettle, through the mechanical transmission structure of rocker, spiral tooth and gear, drives the reaction kettle main body of oblique setting to shake, and the inclination angle makes material natural flow to the low place, and cooperation shaking action can be forced to stir the raw material of bottom deposition to the reaction active region, and forms the up and down linkage with stirring rod, effectively avoids the local raw material accumulation, ensures that ammonia and carbon dioxide and other raw materials contact reaction fully, significantly improves urea synthesis conversion rate.

Description

Technical Field

[0001] This utility model belongs to the field of reaction vessel technology, specifically a reaction vessel for urea production. Background Technology

[0002] Urea, as a core nitrogen fertilizer in agricultural production and a basic raw material in industrial chemicals, relies on the synthesis reaction of ammonia and carbon dioxide under high pressure and high temperature. The reaction places stringent requirements on the sealing of equipment, the accuracy of temperature control, the stability of pressure, and the efficiency of material mixing. As the core equipment for urea synthesis, the performance of the reactor directly determines the yield, purity, and production safety of urea.

[0003] The existing reaction vessels used for urea production have the following main shortcomings:

[0004] In the existing urea synthesis reaction in reactors used for urea production, ammonia and carbon dioxide need to be in full contact under high temperature and high pressure to efficiently generate urea. Uneven mixing of materials can easily lead to localized raw material accumulation and incomplete reaction, which not only reduces the urea conversion rate but also produces byproducts such as biuret, affecting product quality. Furthermore, the pressure inside the reactor changes dynamically due to fluctuations in the amount of raw materials input and changes in the reaction rate. If the pressure exceeds the safety threshold and is not released in time, it may cause safety accidents such as reactor deformation, leakage, or even explosion. If the pressure is released too early or the seal fails after the pressure is released, it will lead to insufficient pressure and interrupt the reaction process. Utility Model Content

[0005] To overcome the above-mentioned defects, this utility model provides a reaction vessel for urea production, which solves the problems in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a reaction vessel for urea production, comprising a shaking frame, a reaction structure at the center of the shaking frame, the reaction structure being inclined, a pressure relief structure at the rear of the center of the upper end face of the reaction structure, a heating structure on the inner side wall of the reaction structure, and a stirring structure at the center of the inside of the reaction structure.

[0007] The reaction structure includes a reaction vessel body, which is located at the center of the shaking frame. A gear is provided at the center of the front end face of the shaking frame, and a helical tooth is meshed on the outer side wall of the gear. A rocker arm is provided at the center of one side wall of the helical tooth.

[0008] As a further embodiment of this utility model: the stirring structure includes a mounting frame, which is located at the center of the upper end face of the reactor body. A servo motor is located at the upper center of the mounting frame. The output end of the servo motor passes through the upper end face of the reactor body and extends into the interior of the reactor body, and a stirring rod is fixedly connected to its end.

[0009] As a further embodiment of this utility model: the pressure relief structure includes a pressure relief pipe, which is located at the rear center of the upper end face of the reactor body. Push plates are provided at the upper and lower center of the inside of the pressure relief pipe, and a hydraulic rod is provided between the two push plates.

[0010] As a further embodiment of this utility model: a force-bearing spring is sleeved on the outside of the hydraulic rod, a pressure relief port is provided at the center of the front end face and the center of the rear end face of the pressure relief pipe, and a pressure inlet is provided at the rear of the center of the upper end face of the reactor body.

[0011] As a further embodiment of this utility model: a cavity is provided at the center of the inner sidewall of the reactor body, and a spiral tube is wound around the center of the cavity. The two ends of the spiral tube pass through the two sidewalls of the cavity and the two inner sidewalls of the reactor body to the outer sidewall of the reactor body.

[0012] As a further embodiment of this utility model: one end of the spiral tube is a steam connection port, the other end of the spiral tube is a condensate discharge port, and the spiral tube is a serpentine tube.

[0013] As a further embodiment of this utility model: a feed hopper is provided at one side of the center of the upper end face of the reaction structure, and a discharge valve is provided at the center of the lower end face of the reaction structure.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] 1. This utility model, through a stirring rod driven by a servo motor, can actively break the concentration and temperature gradients of materials, achieving efficient stirring of materials in the upper part of the reactor. Through the mechanical transmission structure of rocker, helical teeth and gears, the inclined reactor body is driven to shake. The tilt angle causes the materials to flow naturally to the lower part. Combined with the shaking action, the raw materials deposited at the bottom can be forcibly stirred to the active reaction area, forming an up-and-down linkage with the stirring rod, effectively avoiding local raw material accumulation, ensuring full contact and reaction of raw materials such as ammonia and carbon dioxide, and significantly improving the urea synthesis conversion rate.

[0016] 2. This utility model designs a spiral tube in a serpentine shape, which is wound around the cavity inside the inner wall of the reactor. The serpentine structure increases the contact area between the high-temperature steam and the reactor wall compared to a straight tube, allowing heat to be transferred quickly and evenly to the raw materials inside the reactor, avoiding side reactions caused by local overheating. Furthermore, two push plates inside the pressure relief pipe are rigidly connected by a hydraulic rod. The lower push plate directly receives the pressure from the inlet, while the upper push plate, in conjunction with a force spring, forms an elastic buffer threshold. When the pressure inside the reactor slowly increases, the force spring can gradually offset the pressure through elastic deformation, preventing slight pressure fluctuations from triggering accidental pressure relief. Only when the pressure exceeds the spring preload threshold will the two plates be pushed to move upward synchronously to open the pressure relief port, achieving a dynamic adaptation where the higher the pressure, the faster the pressure relief speed, perfectly matching the nonlinear pressure change law in the high-pressure reaction of urea synthesis. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ;

[0018] Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ;

[0019] Figure 3 This is a three-dimensional structural diagram of the stirring structure of this utility model;

[0020] Figure 4 This is a three-dimensional, disassembled structural diagram of the pressure relief structure of this utility model;

[0021] Figure 5 This is a cross-sectional view of the heating structure of this utility model.

[0022] In the diagram: 1. Shaking frame; 2. Reaction structure; 201. Reactor body; 202. Gear; 203. Helical gear; 204. Rocker arm; 3. Stirring structure; 301. Servo motor; 302. Mounting bracket; 303. Stirring rod; 4. Pressure relief structure; 401. Pressure relief pipe; 402. Push plate; 403. Hydraulic rod; 404. Force spring; 405. Pressure discharge port; 406. Pressure inlet; 5. Heating structure; 501. Cavity; 502. Helical tube; 6. Discharge valve; 7. Feed hopper. Detailed Implementation

[0023] The technical solution of this patent will be further described in detail below with reference to specific embodiments.

[0024] like Figures 1-5 As shown, this utility model provides a technical solution:

[0025] A reaction vessel for urea production, comprising:

[0026] The reactor body 201 is equipped with a shaking frame 1, a reaction structure 2 at its center, the reaction structure 2 is inclined, a pressure relief structure 4 is located at the rear of the center of the upper end face of the reaction structure 2, a heating structure 5 is located on the inner side wall of the reaction structure 2, a stirring structure 3 is located at the center of the interior of the reaction structure 2, a feed hopper 7 is located on one side of the center of the upper end face of the reaction structure 2, and a discharge valve 6 is located at the center of the lower end face of the reaction structure 2. The raw materials required for urea production are quantitatively fed into the reactor body 201 according to the process ratio through the feed hopper 7.

[0027] The reaction structure 2 includes a reactor body 201, which is located at the center of the shaking frame 1. A gear 202 is located at the center of the front end face of the shaking frame 1. A helical tooth 203 meshes with the gear 202 on its outer side wall. A rocker arm 204 is located at the center of one side wall of the helical tooth 203. By manually rotating the rocker arm 204, the rocker arm 204 drives the helical tooth 203 on one side to rotate. Since the helical tooth 203 meshes with the gear 202 on the front end face of the shaking frame 1, the rotation of the helical tooth 203 is converted into the rotation of the gear 202, which in turn drives the tilted reactor body 201 to shake. The tilted reactor body 201, in conjunction with the shaking action, enhances the flow characteristics of the raw materials. In particular, it can effectively stir up materials that are easy to settle at the bottom of the reactor body 201 to the reaction area, thereby improving the mixing efficiency and the thoroughness of the reaction.

[0028] The stirring structure 3 includes a mounting frame 302, which is located at the center of the upper end face of the reactor body 201. A servo motor 301 is located at the upper center of the mounting frame 302. The output end of the servo motor 301 passes through the upper end face of the reactor body 201 and extends into the reactor body 201. A stirring rod 303 is fixedly connected to the end of the servo motor 301. When raw materials are added, the servo motor 301 is started. The output end of the servo motor 301 drives the stirring rod 303, which passes through the reactor body 201, to rotate at high speed. The stirring rod 303 forcibly stirs the raw materials inside, breaks the concentration gradient and temperature gradient of the materials, avoids the accumulation of local raw materials due to insufficient reaction, and ensures that all raw materials can fully contact and participate in the reaction.

[0029] The pressure relief structure 4 includes a pressure relief pipe 401, which is located at the rear center of the upper end face of the reactor body 201. Push plates 402 are located at the upper and lower center of the inside of the pressure relief pipe 401, with a hydraulic rod 403 between the two push plates 402. A force spring 404 is sleeved on the outside of the hydraulic rod 403. Pressure outlets 405 are located at the center of the front and rear ends of the pressure relief pipe 401. A pressure inlet 406 is located at the rear center of the upper end face of the reactor body 201. Since the urea synthesis reaction is a high-pressure reaction, when the internal pressure of the reactor body 201 is too high, high-pressure gas enters the pressure relief pipe 401 through the pressure inlet 406, venting pressure on the inside of the pressure relief pipe 405. The lower push plate 402 generates an upward thrust. When the thrust is greater than the preload of the force spring 404, the lower push plate 402 moves upward, compressing the force spring 404. At the same time, it drives the upper push plate 402 to move upward synchronously. As the push plate 402 moves upward, the pressure relief port 405 on the side wall of the pressure relief pipe 401 is opened, and the high-pressure gas is quickly discharged through the pressure relief port 405, reducing the internal pressure of the reactor body 201 to a safe range. When the pressure returns to normal, the force spring 404 releases its elastic potential energy, pushing the two push plates 402 to reset and re-seal the pressure relief port 405, ensuring that the reactor body 201 returns to a sealed state and maintains the pressure environment for subsequent reactions.

[0030] A cavity 501 is provided at the center of the inner wall of the reactor body 201. A spiral tube 502 is wound around the center of the cavity 501. Both ends of the spiral tube 502 pass through the two side walls of the cavity 501 and the two inner side walls of the reactor body 201, respectively, and lead to the outer side wall of the reactor body 201. One end of the spiral tube 502 is a steam connection port, and the other end is a condensate discharge port. The spiral tube 502 is a serpentine tube. After the raw materials are fed in, by connecting an external steam source to the steam connection port of the spiral tube 502, high-temperature steam flows along the serpentine spiral tube 502. 2. The steam flows within the cavity 501. Since the spiral tube 502 is in close contact with the inner wall of the reactor body 201 and the serpentine structure greatly increases the contact area between the steam and the reactor body 201, the heat of the steam can be efficiently transferred to the interior of the reactor body 201, causing the internal raw material temperature to gradually rise to the process temperature required for the urea synthesis reaction. After the reaction is completed or the temperature reaches the set threshold, the steam that has participated in the heat exchange is condensed into water and discharged through the condensate drain at the other end of the spiral tube 502, realizing the recycling of the heating medium and the precise control of the reaction temperature.

[0031] The working principle of this utility model is as follows:

[0032] The raw materials required for urea production are quantitatively fed into the reactor body 201 according to the process ratio through the feed hopper 7. Simultaneously, the servo motor 301 is activated, driving the stirring rod 303, which runs through the reactor body 201, to rotate at high speed. The stirring rod 303 forcibly stirs the internal raw materials, breaking down the concentration and temperature gradients and preventing localized accumulation due to incomplete reaction. This ensures that all raw materials can fully contact and participate in the reaction. After the raw materials are fed, an external steam source is connected to the steam connection port of the spiral tube 502. High-temperature steam flows along the serpentine spiral tube 502 within the cavity 501. Because the spiral tube 502 is tightly attached to the inner wall of the reactor body 201, and the serpentine structure significantly increases the contact area between the steam and the reactor body 201, the heat from the steam can be efficiently transferred to the reactor. Inside the main body 201, the temperature of the internal raw materials is gradually increased to the process temperature required for the urea synthesis reaction. After the reaction is completed or the temperature reaches the set threshold, the steam that has participated in the heat exchange is condensed into water and discharged through the condensate drain at the other end of the spiral tube 502, realizing the recycling of the heating medium and precise control of the reaction temperature. At the same time as the reaction, by manually turning the rocker arm 204, the rocker arm 204 drives the spiral teeth 203 on one side to rotate. Since the spiral teeth 203 meshes with the gear 202 on the front end of the shaking frame 1, the rotation of the spiral teeth 203 is converted into the rotation of the gear 202, which in turn drives the tilted reactor body 201 to shake. The tilted reactor body 201, in conjunction with the shaking action, enhances the flow characteristics of the raw materials. Especially for materials that are easy to settle at the bottom of the reactor body 201, it can effectively stir them into the reaction area, improving the mixing efficiency and the thoroughness of the reaction.

[0033] The urea synthesis reaction is a high-pressure reaction. When the internal pressure of the reactor body 201 is too high, the high-pressure gas enters the pressure relief pipe 401 through the pressure inlet 406, generating an upward thrust on the push plate 402 below the pressure relief pipe 401. When the thrust is greater than the preload of the force spring 404, the lower push plate 402 moves upward, compressing the force spring 404, and simultaneously driving the upper push plate 402 to move upward. As the push plate 402 moves upward, the pressure discharge port 405 on the side wall of the pressure relief pipe 401 is opened, and the high-pressure gas is quickly discharged through the pressure discharge port 405, reducing the internal pressure of the reactor body 201 to a safe range. When the pressure returns to normal, the force spring 404 releases its elastic potential energy, pushing the two push plates 402 to reset and re-seal the pressure discharge port 405, ensuring that the reactor body 201 returns to a sealed state, maintaining the pressure environment for subsequent reactions, and the urea products generated by the reaction are stably discharged through the discharge valve 6.

[0034] Furthermore, the control method of this utility model is controlled by a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Since this utility model is used to protect mechanical devices, the control method and circuit connection will not be explained in detail.

[0035] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A reaction vessel for urea production, characterized in that: It includes a shaking frame (1), a reaction structure (2) is provided at the center of the shaking frame (1), the reaction structure (2) is inclined, a pressure relief structure (4) is provided at the rear of the center of the upper end face of the reaction structure (2), a heating structure (5) is provided on the inner side wall of the reaction structure (2), and a stirring structure (3) is provided at the center of the inside of the reaction structure (2). The reaction structure (2) includes a reaction vessel body (201), which is located at the center of the shaking frame (1). A gear (202) is provided at the center of the front end face of the shaking frame (1). A helical tooth (203) is meshed on the outer side wall of the gear (202), and a rocker arm (204) is provided at the center of one side wall of the helical tooth (203).

2. The reaction vessel for urea production according to claim 1, characterized in that: The stirring structure (3) includes a mounting frame (302), which is located at the center of the upper end face of the reactor body (201). A servo motor (301) is located at the upper center of the mounting frame (302). The output end of the servo motor (301) passes through the upper end face of the reactor body (201) and extends into the interior of the reactor body (201), and a stirring rod (303) is fixedly connected to its end.

3. A reaction vessel for urea production according to claim 1, characterized in that: The pressure relief structure (4) includes a pressure relief pipe (401), which is located at the rear center of the upper end face of the reactor body (201). Push plates (402) are provided at the upper and lower center of the inside of the pressure relief pipe (401), and a hydraulic rod (403) is provided between the two push plates (402).

4. A reaction vessel for urea production according to claim 3, characterized in that: The hydraulic rod (403) is fitted with a force spring (404) on the outside. The pressure relief pipe (401) has a pressure relief port (405) at the center of the front end face and the center of the rear end face. The reactor body (201) has a pressure inlet (406) at the rear of the center of the upper end face.

5. A reaction vessel for urea production according to claim 1, characterized in that: A cavity (501) is provided at the center of the inner wall of the reactor body (201). A spiral tube (502) is wound around the center of the cavity (501). The two ends of the spiral tube (502) pass through the two side walls of the cavity (501) and the two inner side walls of the reactor body (201) respectively, and lead to the outer side wall of the reactor body (201).

6. A reaction vessel for urea production according to claim 5, characterized in that: One end of the spiral tube (502) is a steam connection port, and the other end of the spiral tube (502) is a condensate discharge port. The spiral tube (502) is a serpentine tube.

7. A reaction vessel for urea production according to claim 1, characterized in that: The reaction structure (2) has a feed hopper (7) located at the center of the upper end face and a discharge valve (6) located at the center of the lower end face.

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