Urea production tail gas anti-aggregation mechanism

Abstract

The utility model belongs to the technical field of urea production, and particularly relates to a urea production tail gas anti-aggregation mechanism which comprises a treatment box, filter covers are fixedly installed at the bottoms of the two sides of the treatment box, arc-shaped through grooves are formed in the tops of the filter covers, and arc-shaped fiber nets are movably installed in the arc-shaped through grooves. A separation box is fixedly mounted at the bottom of the filter cover, a bottom cover is movably mounted at the bottom of the separation box, a return pipe is fixedly mounted on one side of the bottom of the bottom cover, and a filter screen is fixedly mounted in the return pipe; through the structural design of the filter cover, the cambered surface fiber net, the separation box, the bottom cover, the return pipe and the filter net and the mutual cooperation of the structures, the solid-liquid separation function is realized, so that the urea production tail gas can be discharged in a split-flow manner, and meanwhile, dust and impurities in the urea production tail gas can be prevented from flowing back, so that the normal work of the urea granulation tower is ensured.

Description

Technical Field

[0001] This utility model relates to the field of urea production technology, specifically a mechanism for preventing the accumulation of tail gas during urea production. Background Technology

[0002] In the urea production unit, molten urea enters the granulation nozzle at the top of the granulation tower. Driven by a motor, the nozzle rotates rapidly, generating centrifugal force. Under this force, the urea inside the nozzle forms countless small droplets, which are sprayed onto the cross-section at the top of the granulation tower. Inside the granulation tower, the molten urea droplets, at a temperature of 140°C, fall freely downwards. During this descent, they undergo mass and heat transfer with the air, gradually cooling and crystallizing to form urea granules that fall onto the "bottom" of the granulation tower. These granules are then pushed by a scraper to the center outlet of the "bottom" and conveyed by a belt to the urea packaging station. The air inside the granulation tower, heated by the 140°C molten urea, becomes less dense and is discharged from the air outlet at the top of the tower. At this time, the internal air pressure decreases, allowing cooler, denser air from outside the tower to enter through the air inlet at the bottom. During the free fall of molten urea droplets within the granulation tower and the subsequent mass and heat transfer with the air, a small amount of urea dust is generated due to mechanical friction. This urea dust, generated by mechanical friction, is discharged from the top of the granulation tower along with the flowing air. Simultaneously, the molten urea carries 0.05 wt% free ammonia. During the granulation process within the tower, some of this free ammonia volatilizes and is discharged into the atmosphere through the top vent of the granulation tower along with the rising air. The dust discharged into the atmosphere drifts a certain distance before settling, which can corrode objects on the ground, and the release of free ammonia into the atmosphere also pollutes the air.

[0003] For example, a urea production tail gas anti-agglomeration mechanism, disclosed in publication (announcement) number CN220779687U, relates to the field of urea production technology. It includes a flange and a main recovery pipe fixedly connected to the upper surface of the flange. Two branch pipes are fixedly connected to the upper end of the main recovery pipe, and solenoid valves are installed on the outer surfaces of the two branch pipes. Compared with existing ordinary urea production tail gas treatment equipment, this urea production tail gas treatment device has its flange installed at the top of the exhaust pipe of the granulation tower. When treating the tail gas, the opening and closing of the solenoid valves can be controlled by the electronic control device built into the granulation tower. The liquid inside the two washing pipes can flow back to the main recovery pipe for recovery through the branch pipes. Simultaneously, the rain and snowproof roof at the top prevents rain and snow from interfering with tail gas emissions. This design allows for maintenance without shutting down the system by controlling the opening and closing of the solenoid valve on one side, and also allows both branch pipes to be opened simultaneously in high-emission conditions to improve tail gas exhaust efficiency.

[0004] However, based on the working principle proposed in the aforementioned patent, the applicant believes that although the device can recover the liquid through the main recovery pipe, the liquid recovery will also simultaneously recover the dust and impurities in the urea production exhaust gas blocked by the fiber mesh, which will cause the dust and impurities to re-enter the exhaust pipe of the granulation tower. This cycle will lead to an increase in the energy consumption of the mechanism. At the same time, directly spraying the rising exhaust gas will increase the airflow resistance, thereby affecting the exhaust gas emission.

[0005] Therefore, a mechanism to prevent the agglomeration of urea production tail gas is proposed to address the above problems. Utility Model Content

[0006] To overcome the shortcomings of existing technologies, such as the inability to separate solids and liquids and the high airflow resistance, this utility model proposes a mechanism to prevent the agglomeration of urea production tail gas.

[0007] The technical solution adopted by this utility model to solve its technical problem is: a urea production tail gas anti-agglomeration mechanism, including a treatment box, on the bottom of both sides of the treatment box a filter cover is fixedly installed, the top of the filter cover is provided with an arc-shaped through groove, an arc-shaped fiber mesh is movably installed inside the arc-shaped through groove, a separation box is fixedly installed at the bottom of the filter cover, a bottom cover is movably installed at the bottom of the separation box, a return pipe is fixedly installed on one side of the bottom of the bottom cover, and a filter screen is fixedly installed inside the return pipe.

[0008] Preferably, an air guide pipe is fixedly installed at the middle part of the bottom of the treatment box, a liquid guide pipe is fixedly installed at the middle part of the top of the treatment box, and a multi-directional atomizing nozzle is fixedly installed at the bottom of the liquid guide pipe.

[0009] Preferably, a rotating shaft is movably installed inside the processing box, and a mounting sleeve is fixedly installed on the surface of the rotating shaft. Exhaust fan blades are fixedly installed on both sides of the surface of the mounting sleeve.

[0010] Preferably, a pulley is fixedly installed at one end of the rotating shaft, and a drive fan blade is fixedly installed on the surface of the other end of the rotating shaft.

[0011] Preferably, a sealing plate is fixedly installed on the top of the arc-shaped fiber mesh, and a first handle is fixedly installed on the middle part of the top of the sealing plate.

[0012] Preferably, a second handle is fixedly installed at the middle part of the bottom of the cover.

[0013] The beneficial effects of this utility model are:

[0014] 1. This utility model achieves solid-liquid separation through the structural design of a filter cover, arc-shaped fiber mesh, separation box, bottom cover, reflux pipe, and filter screen, and through the cooperation between the structures. This allows for the diversion and emission of urea production tail gas, while also preventing the backflow of dust and impurities in the urea production tail gas, thus ensuring the normal operation of the urea granulation tower and solving the problem of solid-liquid separation failure.

[0015] 2. This utility model achieves the function of accelerating gas flow speed through the structural design of rotating shaft, mounting cylinder and exhaust fan blade, and through the cooperation between the structures. This can disturb the production exhaust gas, so that it can come into full contact with the cleaning liquid during the emission process. At the same time, it avoids the disadvantage of the vertical spray direction causing resistance to the gas and solves the problem of high airflow resistance. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a frontal three-dimensional structural diagram of the present invention;

[0018] Figure 2 This is a three-dimensional structural diagram of the present invention viewed from below.

[0019] Figure 3 This is a cross-sectional structural diagram of the filter cover and separation box of this utility model;

[0020] Figure 4 This is a cross-sectional view of the processing box of this utility model.

[0021] In the diagram: 1. Processing box; 2. Filter cover; 3. Arc-shaped channel; 4. Arc-shaped fiber mesh; 5. Separation box; 6. Bottom cover; 7. Return pipe; 8. Filter screen; 9. Air guide pipe; 10. Liquid guide pipe; 11. Multi-directional atomizing nozzle; 12. Rotating shaft; 13. Assembly sleeve; 14. Exhaust fan blade; 15. Pulley; 16. Drive fan blade; 17. Sealing plate; 18. First handle; 19. Second handle. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0023] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0024] This application discloses a mechanism for preventing the agglomeration of tail gas in urea production, including a treatment box 1. Filter covers 2 are fixedly installed on the bottom of both sides of the treatment box 1. An arc-shaped through groove 3 is opened on the top of the filter cover 2. An arc-shaped fiber mesh 4 is movably installed inside the arc-shaped through groove 3. A separation box 5 is fixedly installed at the bottom of the filter cover 2. A bottom cover 6 is movably installed at the bottom of the separation box 5. A return pipe 7 is fixedly installed on one side of the bottom of the bottom cover 6. A filter screen 8 is fixedly installed inside the return pipe 7.

[0025] Reference Figure 1 , Figure 2 , Figure 3 The cooperation of the filter cover 2, the arc-shaped fiber mesh 4, the separation box 5, the bottom cover 6, the return pipe 7, and the filter screen 8 realizes the function of solid-liquid separation. This allows the tail gas of urea production to be diverted and discharged, while also preventing the backflow of dust and impurities in the tail gas of urea production, thus ensuring the normal operation of the urea granulation tower.

[0026] An air guide pipe 9 is fixedly installed at the middle part of the bottom of the treatment box 1, and a liquid guide pipe 10 is fixedly installed at the middle part of the top of the treatment box 1. A multi-directional atomizing nozzle 11 is fixedly installed at the bottom of the liquid guide pipe 10.

[0027] Reference Figure 1 and Figure 4 The liquid guide pipe 10 and the multi-directional atomizing nozzle 11 facilitate the purification and cleaning of the gas and structure inside the treatment box 1, thereby ensuring the efficiency of production exhaust gas purification.

[0028] The processing box 1 has a rotating shaft 12 movably installed inside, and a mounting sleeve 13 is fixedly installed on the surface of the rotating shaft 12. Exhaust fan blades 14 are fixedly installed on both sides of the surface of the mounting sleeve 13.

[0029] Reference Figure 4Through the cooperation of the rotating shaft 12, the mounting cylinder 13, and the exhaust fan blades 14, the function of accelerating the gas flow speed is realized. This can disturb the production exhaust gas, so that it comes into full contact with the cleaning liquid during the emission process. At the same time, it avoids the disadvantage of the vertical spray direction causing resistance to the gas and solves the problem of high airflow resistance.

[0030] A pulley 15 is fixedly installed at one end of the rotating shaft 12, and a drive fan blade 16 is fixedly installed on the surface of the other end of the rotating shaft 12.

[0031] Reference Figure 1 , Figure 2 , Figure 4 The pulley 15 facilitates connection with an external motor to achieve the driving function, thereby driving the exhaust fan blade 14 to rotate, thus accelerating the emission of production exhaust gas. The drive fan blade 16 makes it easy to use the external gas flow speed to drive the exhaust fan blade 14 to rotate, reducing the dependence on electricity in traditional drives. At the same time, the pulley 15 increases the flexibility of the mechanism, so that the appropriate driving method can be selected according to the needs.

[0032] A sealing plate 17 is fixedly installed on the top of the arc-shaped fiber mesh 4, and a first handle 18 is fixedly installed on the middle part of the top of the sealing plate 17.

[0033] Reference Figure 1 and Figure 3 The sealing plate 17 facilitates the sealing of the top opening of the arc-shaped through groove 3, thereby preventing the leakage of production exhaust gas and causing interference to the surrounding ring.

[0034] A second handle 19 is fixedly installed at the middle part of the bottom of the bottom cover 6.

[0035] Reference Figure 2 The second handle 19 allows the staff to adjust the bottom cover 6, thereby cleaning the impurities and dust filtered from the inner cavity of the separation box 5 and closing the bottom of the separation box 5.

[0036] Working principle: When using this device, the exhaust gas is connected to the granulation tower exhaust pipe through the bottom flange of the gas guide pipe 9. After being limited, the exhaust gas is guided into the treatment box 1 through the gas guide pipe 9. The treatment box 1 limits the exhaust gas. The device is connected to an external motor through the pulley 15. The external motor drives the pulley 15 to rotate, which in turn drives the rotating shaft 12 to rotate. Alternatively, the external gas can blow the fan blades 16 to drive the rotating shaft 12 to rotate. As the rotating shaft 12 rotates, it drives the equipped cylinder 13 to rotate synchronously. The exhaust fan blades 14 disturb the exhaust gas, accelerating its emission and moving it towards the filter hood 2 on one side. The exhaust gas is then filtered through the arc-shaped fiber mesh 4. The exhaust gas is filtered, and at the same time, the purified liquid is guided to the multi-directional atomizing nozzle 11 through the liquid guide pipe 10. The purified liquid is atomized and discharged through the multi-directional atomizing nozzle 11. The exhaust gas comes into contact with the purified liquid while being filtered, thus completing the purification. The purified liquid cleans the surface of the arc-shaped fiber mesh 4 and the exhaust fan blade 14 with the impact force. The purified exhaust gas is discharged after passing through the arc-shaped fiber mesh 4. The dust and impurities filtered on the surface of the arc-shaped fiber mesh 4 are slid down into the separation box 5 after being disturbed by the purified liquid. The purified liquid flows back through the return pipe 7 after passing through the filter screen 8. Solid impurities and dust remain inside the separation box 5.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A mechanism for preventing the agglomeration of urea production tail gas, characterized in that: The system includes a processing box (1); filter covers (2) are fixedly installed on the bottom of both sides of the processing box (1); an arc-shaped through groove (3) is opened on the top of the filter cover (2); an arc-shaped fiber mesh (4) is movably installed inside the arc-shaped through groove (3); a separation box (5) is fixedly installed at the bottom of the filter cover (2); a bottom cover (6) is movably installed at the bottom of the separation box (5); a return pipe (7) is fixedly installed on one side of the bottom of the bottom cover (6); and a filter screen (8) is fixedly installed inside the return pipe (7).

2. The anti-agglomeration mechanism for urea production tail gas according to claim 1, characterized in that: An air guide pipe (9) is fixedly installed at the middle part of the bottom of the treatment box (1), a liquid guide pipe (10) is fixedly installed at the middle part of the top of the treatment box (1), and a multi-directional atomizing nozzle (11) is fixedly installed at the bottom of the liquid guide pipe (10).

3. The anti-agglomeration mechanism for urea production tail gas according to claim 1, characterized in that: The processing box (1) is movably installed with a rotating shaft (12), and a mounting sleeve (13) is fixedly installed on the surface of the rotating shaft (12). Exhaust fan blades (14) are fixedly installed on both sides of the surface of the mounting sleeve (13).

4. The anti-agglomeration mechanism for urea production tail gas according to claim 3, characterized in that: A pulley (15) is fixedly installed at one end of the shaft (12), and a drive fan blade (16) is fixedly installed on the surface of the other end of the shaft (12).

5. The anti-agglomeration mechanism for urea production tail gas according to claim 1, characterized in that: A sealing plate (17) is fixedly installed on the top of the arc-shaped fiber mesh (4), and a first handle (18) is fixedly installed in the middle part of the top of the sealing plate (17).

6. The anti-agglomeration mechanism for urea production tail gas according to claim 1, characterized in that: A second handle (19) is fixedly installed at the middle part of the bottom of the bottom cover (6).

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