A combined ceramic filter element dust removal and denitrification device

Abstract

This utility model proposes a combined ceramic filter element dust removal and denitrification device, belonging to the technical field of flue gas treatment devices. It solves the problem that existing dust removal and denitrification devices often place the catalyst inside the filter element, which increases the resistance of the pulse soot blowing process, resulting in poor soot blowing effect. It includes a shell, a pulse dust removal device, and an airflow mixer. The shell includes, from top to bottom, a flue gas outlet, an outlet reducer, a housing, an ash hopper, and an ash discharge port. Inside the housing, a catalyst layer and a dust removal filter element layer are spaced apart from top to bottom. The pulse dust removal device is connected to the housing and located above the dust removal filter element layer. The airflow mixer's outlet is connected to the ash hopper, and its inlet is connected to an external flue gas duct and a reducing agent duct.

Description

Technical Field

[0001] This utility model belongs to the technical field of flue gas treatment devices, and in particular relates to a combined ceramic filter element dust removal and denitrification device. Background Technology

[0002] Industries such as power, steel, and petrochemicals involve combustion processes during industrial production, which generate large amounts of high-temperature flue gas containing harmful substances such as sulfur oxides, nitrogen oxides, and dust. To reduce atmospheric pollution, these harmful substances require effective treatment. Dust removal and denitrification devices, as upstream process equipment in high-temperature flue gas treatment, are crucial for ensuring that dust and nitrogen oxide levels in the flue gas meet standards. Furthermore, the dust and nitrogen oxide content in the treated flue gas affects the desulfurization efficiency in subsequent desulfurization processes; therefore, dust removal and denitrification devices are of paramount importance.

[0003] Denitrification process: Under the action of a catalyst, a reducing agent (ammonia) reacts with nitrogen oxides in flue gas to produce harmless nitrogen and water, thereby removing nitrogen oxides from the flue gas. The temperature range of the denitrification reaction is between 250℃ and 450℃, with the optimal reaction temperature at 300℃. The denitrification reaction will proceed smoothly only within this temperature range. If the dust content in the flue gas is too high, the dust will penetrate the catalyst surface, enter its internal microporous structure, and gradually accumulate, clogging the catalyst micropores and reducing the effective surface area of ​​the catalyst, thus lowering the efficiency of the denitrification reaction. Besides temperature and dust content in the flue gas, the uniformity of mixing the reducing agent with the high-temperature flue gas also affects the denitrification reaction efficiency. Uneven mixing will cause the unit flue gas to not have enough time to contact the unit reducing agent, instead passing directly through the catalyst micropores. The unit reducing agent will also experience "ammonia escape" due to not contacting the unit flue gas, resulting in waste of the reducing agent.

[0004] Existing dust removal and denitrification devices often place the catalyst inside the filter element. The catalyst layer increases the resistance of the pulse soot blowing process, resulting in poor soot blowing effect. Utility Model Content

[0005] In view of this, to address the problem that existing dust removal and denitrification devices often place the catalyst inside the filter element, which increases the resistance of the pulse soot blowing process and leads to poor soot blowing effect, this utility model proposes a combined ceramic filter element dust removal and denitrification device. In this device, the catalyst layer and the dust removal filter layer are spaced apart, and the pulse soot blowing device is positioned above the dust removal filter layer. The soot blowing process is unaffected by the catalyst layer, resulting in good soot blowing effect. Simultaneously, the airflow during the soot blowing process effectively promotes the mixing of ammonia and high-temperature flue gas, making the mixing more uniform, reducing ammonia escape, and improving the denitrification reaction efficiency.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a combined ceramic filter element dust removal and denitrification device, comprising a housing, a pulse dust removal device, and an airflow mixer. The housing includes a flue gas outlet, an outlet reducer, a box, an ash hopper, and an ash discharge port connected sequentially from top to bottom. Inside the box, a catalyst layer and a dust removal filter element layer are spaced apart from top to bottom. The pulse dust removal device is connected to the box and located between the catalyst layer and the dust removal filter element layer on the side close to the dust removal filter element layer. The airflow mixer's outlet is connected to the ash hopper, and its inlet is connected to an external flue gas pipe and a reducing agent pipe, respectively.

[0007] Furthermore, the catalyst layer has a honeycomb structure in which the catalyst is placed.

[0008] Furthermore, the housing also includes a grating plate and a perforated plate, both of which are connected to the inner wall of the housing. The catalyst layer is placed on the grating plate, and the dust removal filter layer is connected to the perforated plate.

[0009] Furthermore, it also includes a screw conveyor, the bottom of the ash hopper is strip-shaped, the ash discharge port is located at one end of the strip, and the screw conveyor passes through the ash hopper and is connected to the bottom side wall of the ash hopper.

[0010] Furthermore, the pulse dust removal device includes a dust removal air chamber and multiple blow pipes. The dust removal air chamber is located outside the housing and connected to the housing, while the blow pipes are located inside the housing and connected to the housing. The dust removal air chamber and the blow pipes are connected in series.

[0011] Furthermore, the dust removal air bag includes a seamless steel pipe and multiple air outlet pipes. One end of the seamless steel pipe is sealed and the other end is connected to an external compressed air pipeline. The body of the seamless steel pipe is connected to the multiple air outlet pipes.

[0012] Furthermore, a pulse valve is provided on the air outlet pipe.

[0013] Furthermore, the blowpipe includes a seamless steel pipe and multiple nozzles. One end of the seamless steel pipe is sealed and the other end is connected to the air outlet pipe of the dust collector air bag. The pipe body of the seamless steel pipe is connected to multiple nozzles, and the nozzles face the dust collector filter layer.

[0014] Furthermore, the pulse dust removal device also includes a pipe compensator, through which the seamless steel pipe II is connected to the air outlet pipe.

[0015] Furthermore, the dust removal filter layer includes multiple ceramic fiber filter elements, which are connected to the holes of the perforated plate. The ceramic fiber filter elements are test tube shaped with their openings facing the nozzles of the blowpipe.

[0016] Compared with the prior art, the beneficial effects of the combined ceramic filter dust removal and denitrification device of this utility model are:

[0017] 1. The catalyst layer and dust removal filter element layer of this utility model are set separately, which avoids the problem of high resistance in the pulse soot blowing process caused by placing the catalyst in the filter element in the existing equipment. This ensures the cleaning efficiency of the pulse soot blowing process and the promoting effect of the gas mass on the mixing of ammonia and high temperature flue gas during the soot blowing process, thereby improving the efficiency of the denitrification reaction.

[0018] 2. This utility model is equipped with an airflow mixer, a pulse dust removal device and a ceramic fiber filter element, which mixes ammonia and high-temperature flue gas three times to make the mixing more uniform, reduce the occurrence of "ammonia escape" and improve the denitrification reaction efficiency.

[0019] 3. The dust removal filter element of this utility model adopts ceramic fiber filter element, which has high dust removal efficiency and extends the service life of the catalyst. The ceramic fiber filter element can be used at a maximum temperature of 500℃, and the long-term operating temperature can be kept stable between 250℃ and 450℃. It is suitable for high-temperature flue gas dust removal. Moreover, the operating temperature of the ceramic fiber filter element coincides with the reaction temperature of the denitrification reaction, so that the denitrification reaction can continue to proceed at the temperature that meets the conditions.

[0020] 4. This utility model takes into account the large temperature difference between the working environment of the dust collector air bag and the blow pipe, and the change in the length of the connecting pipe between the two caused by thermal expansion and contraction. A pipe compensator is specifically designed to flexibly connect the dust collector air bag and the blow pipe, avoiding structural damage and disconnection of the dust collector air bag and the blow pipe that may be caused by fixed-length pipes. Attached Figure Description

[0021] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0022] Figure 1 This is a front view of the combined ceramic filter element dust removal and denitrification device described in this utility model;

[0023] Figure 2 This is a partial cross-sectional view of a combined ceramic filter element dust removal and denitrification device according to the present invention;

[0024] Figure 3 This utility model Figure 2 A sectional view along line A in the middle;

[0025] Figure 4 This utility model Figure 2 Sectional view along line B;

[0026] Figure 5 This is a top view of the grating plate described in this utility model;

[0027] Figure 6This is a top view of the perforated plate described in this utility model;

[0028] Figure 7 This is a cross-sectional view of the dust removal air bag described in this utility model;

[0029] Figure 8 This is a schematic diagram of the structure of the blowpipe described in this utility model;

[0030] Figure 9 This utility model Figure 2 A magnified view of a section at point C;

[0031] Figure 10 This utility model Figure 3 A magnified view of a section at point E in the middle;

[0032] In the diagram: 1-Flue gas outlet; 2-Outlet reducer; 3-Box; 4-Ash hopper; 5-Ash discharge port; 6-Airflow mixer; 7-Screw conveyor; 8-Dust collector air manifold; 9-Pulse jet pipe;

[0033] 31-Catalyst layer; 32-Dust collector filter layer; 33-Grate plate; 34-Perforated plate;

[0034] 81-Seamless steel pipe; 82-Gas outlet pipe; 83-Pipe compensator;

[0035] 91-Seamless steel pipe II; 92-Nozzle; D-Compressed air source. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present utility model can be combined with each other, and the described embodiments are only some embodiments of the present utility model, not all embodiments.

[0037] I. Detailed Implementation Method 1, see [link / reference] Figure 1-10 This embodiment describes a combined ceramic filter dust removal and denitrification device, comprising a housing, a pulse dust collector, and an airflow mixer 6. The housing includes, from top to bottom, a flue gas outlet 1, an outlet reducer 2, a housing 3, an ash hopper 4, and an ash discharge port 5. Inside the housing 3, a catalyst layer 31 and a dust collector filter layer 32 are spaced apart from top to bottom. The pulse dust collector is connected to the housing 3 and is located between the catalyst layer 31 and the dust collector filter layer 32, closer to the dust collector filter layer 32. The outlet of the airflow mixer 6 is connected to the ash hopper 4, and the inlet is connected to an external flue gas duct and a reducing agent duct, respectively.

[0038] The catalyst layer 31 has a honeycomb structure, which has a large specific surface area and contains the catalyst, thus facilitating the denitrification reaction. The catalyst layer 31 can be configured as a multi-layer structure.

[0039] The airflow mixer 6 has a high-temperature flue gas inlet, an ammonia inlet, and four outlets. The high-temperature flue gas inlet is connected to an external flue gas pipeline, the ammonia inlet is connected to an external reducing agent pipeline, and all four outlets are connected to the ash hopper 4.

[0040] The housing 3 also includes a grating plate 33 and a perforated plate 34, both of which are connected to the inner wall of the housing 3. A catalyst layer 31 is placed on the grating plate 33, and a dust filter layer 32 is connected to the perforated plate 34. The catalyst layer 31 is composed of catalyst modules. Two layers of grating plates 33 are horizontally arranged on the upper part of the housing 3, and the grating plates 33 are welded to the inner wall of the housing 3 on all four sides. A total of 18 catalyst modules are arranged on the upper part of the grating plates 33. A perforated plate 34 is horizontally arranged below the two layers of grating plates 33 inside the housing 3, and the perforated plate 34 is welded to the inner wall of the housing 3 on all four sides.

[0041] The combined ceramic filter dust removal and denitrification device also includes a screw conveyor 7. The bottom of the ash hopper 4 is strip-shaped, and the ash discharge port 5 is located at one end of the strip. The screw conveyor 7 passes through the ash hopper 4 and is connected to the bottom side wall of the ash hopper 4. The screw conveyor 7 is installed at the bottom of the ash hopper 4 and is driven by its own motor.

[0042] The pulse dust collector includes a dust collection air manifold 8 and multiple blowpipes 9. The dust collection air manifold 8 is located outside the housing 3 and connected to it, while the blowpipes 9 are located inside the housing 3 and connected to it. The dust collection air manifold 8 and the blowpipes 9 are interconnected. The side wall of the housing 3 has multiple openings for installing the blowpipes 9. There are two dust collection air manifolds 8, symmetrically arranged on both sides of the housing 3, and a total of 32 blowpipes 9.

[0043] The dust removal air chamber 8 includes a seamless steel pipe 81 and multiple air outlet pipes 82. One end of the seamless steel pipe 81 is sealed and the other end is connected to an external compressed air pipeline. The pipe body of the seamless steel pipe 81 is connected to the multiple air outlet pipes 82. The multiple air outlet pipes 82 are arranged linearly and uniformly along the length of the seamless steel pipe 81.

[0044] A pulse valve is provided on the air outlet pipe 82.

[0045] The blowpipe 9 includes a seamless steel pipe 91 and multiple nozzles 92. One end of the seamless steel pipe 91 is sealed, and the other end is connected to the air outlet pipe 82 of the dust collector air manifold 8. The pipe body of the seamless steel pipe 91 is connected to the multiple nozzles 92, and the nozzles 92 face the dust collector filter layer 32. The multiple nozzles 92 are arranged linearly and uniformly along the length of the seamless steel pipe 91.

[0046] The pulse dust collector also includes a pipe compensator 83, which connects the seamless steel pipe 91 to the outlet pipe 82. The pipe compensator 83 consists of multiple U-shaped compensating joints. During installation, the seamless steel pipe 91 and the outlet pipe 82 are connected at room temperature. During operation, the seamless steel pipe 91 and the outlet pipe 82 are located inside and outside the equipment, respectively. The inside of the equipment is a high-temperature environment, while the outside is a room-temperature environment, resulting in a significant temperature difference and changes in the distance between them due to thermal expansion and contraction. The pipe compensator 83 can freely adjust its length to prevent connection failure between the seamless steel pipe 91 and the outlet pipe 82. There are 32 pipe compensators 83 in total.

[0047] The dust collector filter layer 32 includes multiple ceramic fiber filter elements, which are connected to the holes in the perforated tube sheet 34. Each ceramic fiber filter element is test-tube shaped, with its opening facing the nozzle 92 of the blowpipe 9. There are a total of 160 ceramic fiber filter elements.

[0048] The working principle of this invention is as follows: High-temperature flue gas containing dust and ammonia gas enter the airflow mixer 6 through their respective inlets and mix. After mixing, the gas enters the ash hopper 4 through four outlets. During this process, ammonia gas and high-temperature flue gas complete a primary mixing. Under the negative pressure provided by other equipment on the production line, the high-temperature flue gas mixed with ammonia gas enters from the outside of the ceramic fiber filter element. During the process of passing through the filter element, the dust contained therein is blocked on the outer surface of the ceramic fiber filter element. The dust-removed flue gas is discharged from the top outlet of the ceramic fiber filter element. During the process of passing through the filter element, ammonia gas and high-temperature flue gas complete a secondary mixing inside the ceramic fiber filter element. When the amount of dust on the outside of the ceramic fiber filter element is too thick, the pulse valve is activated. Compressed air in the dust removal air tank 8 enters the blowpipe 9 instantaneously through the pulse valve. The airflow formed by the pulse airflow is sprayed into the interior of the ceramic fiber filter element through the nozzle 92. Under the action of the airflow, the dust on the outside of the ceramic fiber filter element is cleaned, thus completing one dust removal process. At the same time, under the action of the airflow, ammonia gas and mixed gas complete a third mixing.

[0049] The dust that is removed falls to the bottom of the ash hopper 4. The screw conveyor 7 is started, and the dust is pushed into the ash discharge port 5 by the action of the screw blades.

[0050] High-temperature flue gas containing ammonia enters the upper part of chamber 3 after dust removal. It passes through catalyst layer 31 to react ammonia with nitrogen oxides in the high-temperature flue gas to generate nitrogen and water, and is finally discharged through high-temperature flue gas outlet 1.

[0051] The embodiments of the present invention disclosed above are merely illustrative of the present invention. The embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A combined ceramic filter element dust removal and denitrification device, characterized in that: The device includes a housing, a pulse dust collector, and an airflow mixer (6). The housing includes a flue gas outlet (1), an outlet reducer (2), a housing (3), an ash hopper (4), and an ash discharge port (5) connected sequentially from top to bottom. Inside the housing (3), a catalyst layer (31) and a dust filter layer (32) are spaced apart from top to bottom. The pulse dust collector is connected to the housing (3) and is located between the catalyst layer (31) and the dust filter layer (32) on the side close to the dust filter layer (32). The outlet of the airflow mixer (6) is connected to the ash hopper (4), and the inlet is connected to the external flue gas pipe and the reducing agent pipe, respectively.

2. The combined ceramic filter element dust removal and denitrification device according to claim 1, characterized in that: The catalyst layer (31) has a honeycomb structure and contains the catalyst.

3. The combined ceramic filter element dust removal and denitrification device according to claim 1, characterized in that: The housing (3) also includes a grid plate (33) and a perforated plate (34), both of which are connected to the inner wall of the housing (3). The catalyst layer (31) is placed on the grid plate (33), and the dust removal filter layer (32) is connected to the perforated plate (34).

4. The combined ceramic filter element dust removal and denitrification device according to claim 1, characterized in that: It also includes a screw conveyor (7), the bottom of the ash hopper (4) is strip-shaped, the ash discharge port (5) is located at one end of the strip, the screw conveyor (7) passes through the ash hopper (4) and is connected to the bottom side wall of the ash hopper (4).

5. The combined ceramic filter element dust removal and denitrification device according to claim 1, characterized in that: The pulse dust removal device includes a dust removal air bag (8) and multiple blow pipes (9). The dust removal air bag (8) is located outside the housing (3) and connected to the housing (3). The blow pipes (9) are located inside the housing (3) and connected to the housing (3). The dust removal air bag (8) and the blow pipes (9) are connected.

6. The combined ceramic filter element dust removal and denitrification device according to claim 5, characterized in that: The dust removal air bag (8) includes a seamless steel pipe (81) and multiple air outlet pipes (82). One end of the seamless steel pipe (81) is sealed and the other end is connected to an external compressed air pipeline. The pipe body of the seamless steel pipe (81) is connected to the multiple air outlet pipes (82).

7. The combined ceramic filter element dust removal and denitrification device according to claim 6, characterized in that: A pulse valve is provided on the air outlet pipe (82).

8. The combined ceramic filter element dust removal and denitrification device according to claim 7, characterized in that: The blowpipe (9) includes a seamless steel pipe (91) and a plurality of nozzles (92). One end of the seamless steel pipe (91) is sealed and the other end is connected to the air outlet pipe (82) of the dust removal air bag (8). The pipe body of the seamless steel pipe (91) is connected to the plurality of nozzles (92), and the nozzles (92) face the dust removal filter layer (32).

9. A combined ceramic filter element dust removal and denitrification device according to claim 8, characterized in that: The pulse dust removal device also includes a pipe compensator (83), and the seamless steel pipe (91) and the air outlet pipe (82) are connected through the pipe compensator (83).

10. A combined ceramic filter element dust removal and denitrification device according to claim 9, characterized in that: The dust removal filter layer (32) includes multiple ceramic fiber filter elements, which are connected to the holes of the perforated plate (34). The ceramic fiber filter elements are in the shape of test tubes, with their openings facing the nozzles (92) of the blowpipe (9).

Images