Tail gas treatment equipment for melamine production

Abstract

The utility model discloses tail gas treatment equipment for melamine production, belongs to the technical field of tail gas treatment, and mainly solves the problems that equipment in the prior art is poor in tail gas absorption effect, the contact surface area of absorption liquid and tail gas is small and is not beneficial to full reaction compared with a spraying absorption mode, and the tail gas is difficult to absorb during spraying absorption. The tail gas treatment equipment comprises a treatment box, a filter shell is arranged on one side of the treatment box, a gas guide cover is fixedly connected into the filter shell, a threaded groove is formed in one side of the gas guide cover, a mounting frame is mounted in the threaded groove in a threaded mode, a filter screen is fixedly connected into the mounting frame, and the filter screen is fixedly connected with the filter shell. An outer-layer cylinder and an inner-layer cylinder are fixedly connected to the side, close to the treatment box, of the gas guide cover, a plurality of air holes are formed in the outer-layer cylinder and the inner-layer cylinder in a penetrating mode, a spraying pipe is arranged on the treatment box in a penetrating mode, a plurality of spraying discs are installed on the spraying pipe, and atomizing nozzles are installed at the bottoms of the spraying discs.

Description

Technical Field

[0001] This utility model relates to the field of exhaust gas treatment technology, and more specifically, to an exhaust gas treatment device for melamine production. Background Technology

[0002] Melamine is an important organic chemical raw material. The most widely used industrial method for producing melamine is the urea process. Melamine has a wide range of applications and a large output, making it a large market with broad application prospects. However, the production process of melamine generates a large amount of mixed gas containing ammonia and carbon dioxide, which is the melamine industrial tail gas. Tail gas treatment equipment is needed to purify the tail gas.

[0003] However, existing technologies offer a variety of tail gas treatment equipment. For example, utility model patent CN213643642U relates to a tail gas absorption device in the melamine production process. This utility model includes a Roots blower, a water absorption tower, a cyclone separator, and an acid absorption tower connected in sequence. The acid absorption tower has a packing section, a bubble cap section, and a demister arranged sequentially from bottom to top. The lower air inlet of the packing section of the acid absorption tower is connected to the gas outlet of the cyclone separator, and the upper liquid inlet is connected to the acid absorption liquid pipeline. The top of the acid absorption tower is connected to a tail gas discharge pipeline. This utility model's tail gas absorption device in the melamine production process has a simple structure and is easy to operate. It not only effectively absorbs the ammonia contained in the tail gas, achieving complete absorption and utilization of the ammonia in the tail gas, but also ensures that the treated tail gas is free of acid mist, thus saving energy, protecting the environment, and reducing consumption.

[0004] Although the device uses a combination of water absorption towers and acid absorption towers to absorb ammonia in the exhaust gas, the absorption effect is not good during use. Compared with the spray absorption method, the contact surface area between the absorbent liquid and the exhaust gas is small, which is not conducive to a full reaction. Furthermore, the small solid particles in the exhaust gas during the spray absorption process will affect the absorption effect of the spray treatment method. To avoid this phenomenon, it is necessary to design an exhaust gas treatment device for melamine production. Utility Model Content

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0006] To achieve the above objectives, this utility model provides a tail gas treatment device for melamine production, which is achieved by the following specific technical means:

[0007] A melamine production tail gas treatment device includes a treatment box, a filter housing connected to the treatment box, a gas guide hood fixedly connected inside the filter housing, a threaded groove on one side of the gas guide hood, a mounting frame threaded into the threaded groove, a filter screen fixedly connected inside the mounting frame, an outer cylinder and an inner cylinder fixedly connected to the gas guide hood, an annular cavity formed between the outer cylinder and the inner cylinder, a cylindrical activated carbon filter material disposed inside the annular cavity, a number of air vents penetrating both the outer cylinder and the inner cylinder, a spray pipe penetrating the treatment box, a number of spray discs mounted on the spray pipe, the multiple spray discs being located inside the treatment box, and an atomizing nozzle mounted at the bottom of the spray discs.

[0008] Preferably, an installation ring is coaxially provided on the outer surface of the outer cylinder, and a sealing cover is installed on one side of the installation ring by connecting bolts. The sealing cover is sleeved on the end of the outer cylinder and is used to seal the activated carbon filter material. A retainer is provided on one side of the sealing cover, and a sealing ring is provided inside the retainer.

[0009] Preferably, the outer cylinder and the inner cylinder are concentric, and the ends of the outer cylinder and the inner cylinder can be embedded in the retainer to compress the sealing ring and achieve the purpose of sealing; the mounting frame is annular.

[0010] Preferably, an air inlet pipe is connected to the end of the filter housing away from the treatment box, and an exhaust fan is installed at the end of the filter housing close to the treatment box. The output end of the exhaust fan is connected to an air supply pipe, and one end of the air supply pipe extends into the treatment box. The air supply pipe is fixed below the spray pipe, and multiple air outlets are opened on the outer surface of the portion of the air supply pipe located inside the treatment box.

[0011] Preferably, a housing is provided on one outer surface of the treatment box, a water pump is installed inside the housing, and the output end of the water pump is connected to one end of the spray pipe.

[0012] Preferably, a control valve is installed on the surface of the spray pipe, and two connecting rods are fixed to the inner top wall of the treatment box, with one end of the connecting rods fixedly connected to the spray pipe.

[0013] Preferably, a duct is detachably installed on the top of the processing box, and an exhaust fan is installed inside the duct.

[0014] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0015] When treating the exhaust gas generated during melamine production, the solid particulate impurities contained in the exhaust gas are first filtered and intercepted to prevent them from affecting the absorption effect of subsequent spraying operations. Then, during the countercurrent upward flow of the exhaust gas, the absorbent liquid is atomized and sprayed using atomizing nozzles, so that the rising exhaust gas and the atomized liquid droplets come into countercurrent contact. This increases the surface area of ​​gas-liquid contact, ensuring sufficient reaction between the exhaust gas and the absorbent liquid, and improving the absorption effect of ammonia in the exhaust gas. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0017] Figure 1 This is a perspective structural diagram of the present invention;

[0018] Figure 2 This is a schematic diagram of the internal structure of the filter housing;

[0019] Figure 3 This is a schematic diagram of the outer and inner cylinders.

[0020] Figure 4 This is a schematic diagram of the spray assembly.

[0021] Figure 5 This is a schematic diagram of the structure where the gas pipeline extends into the processing box.

[0022] In the diagram: 1. Processing box; 2. Filter housing; 3. Air guide hood; 4. Threaded groove; 5. Mounting frame; 6. Filter screen; 7. Outer cylinder; 8. Inner cylinder; 9. Activated carbon filter media; 10. Vent hole; 11. Spray pipe; 12. Spray disc; 13. Atomizing nozzle; 14. Mounting ring; 15. Sealing cover; 16. Card holder; 17. Sealing ring; 18. Housing; 19. Water pump; 20. Control valve; 21. Air inlet pipe; 22. Exhaust fan; 23. Air delivery pipe; 24. Air outlet; 25. Air duct; 26. Exhaust fan. Detailed Implementation

[0023] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. The present invention provides the following embodiments.

[0026] like Figure 1 , Figure 2 as well as Figure 3 As shown, this is a schematic diagram of the tail gas treatment equipment for melamine production in this embodiment. The tail gas treatment equipment in this embodiment includes a treatment box 1. A filter shell 2 is provided on one side of the treatment box 1. An air inlet pipe 21 is connected to the end of the filter shell 2 away from the treatment box 1. An air guide hood 3 is fixedly connected inside the filter shell 2. A threaded groove 4 is opened on one side of the air guide hood 3. An installation frame 5 is threaded in the threaded groove 4. A filter screen 6 is fixedly connected inside the installation frame 5. During the treatment of the tail gas generated in melamine production, the tail gas, such as carbon dioxide and ammonia, is introduced into the filter shell 2 through the air inlet pipe 21. After being guided by the air guide hood 3, the tail gas passes through the filter screen 6 on the installation frame 5. The installed filter screen 6 intercepts and filters the solid particulate impurities in the tail gas, removing them as solid particles in the tail gas to prevent them from affecting the absorption effect of subsequent spraying operations. When the filter screen 6 becomes clogged and affects its filtration effect, the adjustment plate on the installation frame 5 is moved to unscrew the installation frame 5 from the threaded groove 4 so that the filter screen 6 can be removed for cleaning.

[0027] In this embodiment, an outer cylinder 7 and an inner cylinder 8 are fixedly connected to the side of the air guide hood 3 near the treatment box 1. An annular cavity can be formed between the outer cylinder 7 and the inner cylinder 8. A cylindrical activated carbon filter material 9 is provided in the annular cavity. Both the outer cylinder 7 and the inner cylinder 8 are provided with a number of vent holes 10. The exhaust gas with small particulate impurities removed passes through the filter screen 6 and is introduced into the inner cylinder 8. Along the gas flow direction, it passes through the vent holes 10 of the inner cylinder 8 and enters the annular cavity. Then, by utilizing the characteristics of the activated carbon filter material 9, it can simultaneously perform preliminary adsorption treatment on the ammonia in the flowing exhaust gas. The exhaust gas with the preliminary removal of ammonia will then be discharged from the vent holes 10 of the outer cylinder 7.

[0028] like Figure 4As shown, this is a schematic diagram of the spray assembly in this embodiment. In this embodiment, a spray pipe 11 is installed through the treatment box 1. Multiple spray discs 12 are installed on the spray pipe 11 and are located inside the treatment box 1. Atomizing nozzles 13 are installed at the bottom of the spray discs 12. A housing 18 is provided on one outer surface of the treatment box 1. A water pump 19 is installed inside the housing 18, and the output end of the water pump 19 is connected to one end of the spray pipe 11. When the exhaust gas with small particulate impurities removed is introduced into the treatment box 1, the water pump 19 draws the pre-prepared absorbent into the spray pipe 11. After being transported by the spray pipe 11, the absorbent is atomized and sprayed by the atomizing nozzles 13 on the multiple spray discs 12, so that the rising exhaust gas and the atomized droplets make countercurrent contact, thereby expanding the surface area of ​​gas-liquid contact and ensuring that the exhaust gas and absorbent react fully during countercurrent, further improving the absorption effect of ammonia in the exhaust gas.

[0029] It is worth noting that in this embodiment, the spray pipe 11, spray disc 12, atomizing nozzle 13 and water pump 19 constitute a spray assembly. A control valve 20 is installed on the surface of the spray pipe 11. Two connecting rods are fixed to the inner top wall of the treatment box 1, and one end of the connecting rod is fixedly connected to the spray pipe 11.

[0030] like Figure 3 As shown, in this embodiment, an installation ring 14 is coaxially provided on the outer surface of the outer cylinder 7. A sealing cover 15 is installed on one side of the installation ring 14 by connecting bolts, and the sealing cover 15 is sleeved on the end of the outer cylinder 7. A retainer 16 is provided on one side of the sealing cover 15, and a sealing ring 17 is provided in the retainer 16. When the activated carbon filter material 9 needs to be cleaned or replaced, the connecting bolts are loosened, and the sealing cover 15 can be removed to release the blockage of the outer cylinder 7, the inner cylinder 8 and the activated carbon filter material 9, and the activated carbon filter material 9 can be directly extracted from the annular cavity.

[0031] like Figure 2 as well as Figure 5 As shown, in this embodiment, an exhaust fan 22 is installed at one end of the filter housing 2 near the treatment box 1. The output end of the exhaust fan 22 is connected to an air supply pipe 23, and one end of the air supply pipe 23 extends into the treatment box 1. The air supply pipe 23 is fixed below the spray pipe 11. Multiple air outlets 24 are opened on the outer surface of the portion of the air supply pipe 23 located inside the treatment box 1. When processing the produced exhaust gas, the exhaust fan 22 is started, so that the exhaust gas is introduced into the filter housing 2 through the air inlet pipe 21. After the filtration process is completed, the exhaust gas is introduced into the air supply pipe 23 through the exhaust fan 22. After being transported by the air supply pipe 23, the exhaust gas is discharged into the treatment box 1 from multiple air outlets 24 to facilitate subsequent spraying operations.

[0032] like Figure 5As shown, it is a structural schematic diagram of the air duct 25 in this embodiment. In this embodiment, the top of the processing box 1 is detachably equipped with the air duct 25. An exhaust fan 26 is installed inside the air duct 25. When the exhaust gas is discharged from the outlet 24, the exhaust fan 26 is started at the same time. The exhaust gas is discharged to the outside through the exhaust fan 26, so that the discharged exhaust gas rises with the airflow, so that the exhaust gas can make subsequent countercurrent contact.

[0033] It is worth noting that in this embodiment, the outer cylinder 7 and the inner cylinder 8 are concentric, and the ends of the outer cylinder 7 and the inner cylinder 8 can be embedded in the card seat 16 to compress the sealing ring 17, so as to achieve the purpose of sealing.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tail gas treatment device for melamine production, comprising a treatment chamber (1), a filter housing (2) connected to the treatment chamber (1), and a gas guide hood (3) fixedly connected inside the filter housing (2), characterized in that: A threaded groove (4) is provided on one side of the air guide hood (3). A mounting frame (5) is installed in the threaded groove (4). A filter screen (6) is fixedly connected inside the mounting frame (5). An outer cylinder (7) and an inner cylinder (8) are fixedly connected to the air guide hood (3). An annular cavity can be formed between the outer cylinder (7) and the inner cylinder (8). A cylindrical activated carbon filter material (9) is provided inside the annular cavity. Several air vents (10) are provided through the outer cylinder (7) and the inner cylinder (8). A spray pipe (11) is provided through the treatment box (1). Multiple spray plates (12) are installed on the spray pipe (11). The multiple spray plates (12) are located inside the treatment box (1). An atomizing nozzle (13) is installed at the bottom of the spray plate (12).

2. The melamine production tail gas treatment equipment according to claim 1, characterized in that: An installation ring (14) is coaxially provided on the outer surface of the outer cylinder (7). A sealing cover (15) is installed on one side of the installation ring (14) by connecting bolts. The sealing cover (15) is sleeved on the end of the outer cylinder (7). The sealing cover (15) is used to seal the activated carbon filter material (9). A card seat (16) is provided on one side of the sealing cover (15). A sealing ring (17) is provided inside the card seat (16).

3. The melamine production tail gas treatment equipment according to claim 1, characterized in that: The outer cylinder (7) and the inner cylinder (8) are concentric. The ends of the outer cylinder (7) and the inner cylinder (8) can be embedded in the card seat (16) to compress the sealing ring (17) for the purpose of sealing. The mounting frame (5) is annular.

4. The melamine production tail gas treatment equipment according to claim 1, characterized in that: The filter housing (2) is connected to an air inlet pipe (21) at the end away from the treatment box (1). An exhaust fan (22) is installed at the end of the filter housing (2) close to the treatment box (1). An air supply pipe (23) is connected to the output end of the exhaust fan (22). One end of the air supply pipe (23) extends into the treatment box (1). The air supply pipe (23) is fixed below the spray pipe (11). Multiple air outlets (24) are opened on the outer surface of the part of the air supply pipe (23) located inside the treatment box (1).

5. The melamine production tail gas treatment equipment according to claim 1, characterized in that: A housing (18) is provided on one side of the outer surface of the treatment box (1). A water pump (19) is installed inside the housing (18), and the output end of the water pump (19) is connected to one end of the spray pipe (11).

6. The melamine production tail gas treatment equipment according to claim 1, characterized in that: A control valve (20) is installed on the surface of the spray pipe (11), and two connecting rods are fixed on the inner top wall of the treatment box (1), with one end of the connecting rods fixedly connected to the spray pipe (11).

7. The melamine production tail gas treatment equipment according to claim 1, characterized in that: The top of the processing box (1) is detachably equipped with a duct (25), and an exhaust fan (26) is installed inside the duct (25).

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