A new low-temperature SCR denitration equipment

Abstract

This utility model discloses a novel low-temperature SCR denitrification device, belonging to the field of flue gas treatment technology. It includes a denitrification chamber and a dust collection chamber arranged side-by-side. The tops of the denitrification chamber and the dust collection chamber are connected together via a chimney. The bottom ends of the denitrification chamber and the dust collection chamber, furthest from each other, are respectively provided with a flue gas outlet and a flue gas inlet. Flue gas passes sequentially through the flue gas inlet, the dust collection chamber, the chimney, the denitrification chamber, and the flue gas outlet. An SCR module is located in the middle of the denitrification chamber. A second blowing device is installed above the SCR module, with its piping extending out of the denitrification chamber and connected to a main hot steam pipe. A flow-rectifying grid is located above the second blowing device, below the chimney. A discharge valve is located below the bottom collection chamber of the denitrification chamber. This utility model uses a second blowing device installed above the SCR module for ash removal, resulting in strong ash removal and effective removal of ash and sticky deposits from the catalyst channels.

Description

Technical Field

[0001] This utility model relates to the field of flue gas treatment technology, and in particular to a novel low-temperature SCR denitrification device. Background Technology

[0002] Low-temperature SCR denitrification equipment is a system specifically designed for the efficient removal of nitrogen oxides at relatively low flue gas temperatures (typically in the range of 120℃ to 300℃, and even as low as 80℃). It solves the denitrification problems in industries such as steel sintering, coking, glass, ceramics, chemicals, some gas-fired boilers (especially during low-load operation), waste incineration (certain sections), and coal-fired power plants where flue gas temperatures have been significantly reduced after the installation of wet desulfurization. At low temperatures (especially below the dew point temperature of ammonium bisulfate, approximately 150-200℃), SO3 in the flue gas reacts with escaped NH3 to form viscous ammonium bisulfate, which easily clogs catalyst pores and adheres to the catalyst surface. Based on this, this invention proposes a novel low-temperature SCR denitrification device. Utility Model Content

[0003] The purpose of this invention is to provide a novel low-temperature SCR denitrification device that solves the problem of catalyst pore blockage.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] This utility model discloses a novel low-temperature SCR denitrification device, comprising a denitrification chamber and a dust removal chamber arranged side by side. The tops of the denitrification chamber and the dust removal chamber are connected together by a chimney. The bottom ends of the denitrification chamber and the dust removal chamber, which are far from each other, are respectively provided with a flue gas outlet and a flue gas inlet. The flue gas passes through the flue gas inlet, the dust removal chamber, the chimney, the denitrification chamber, and the flue gas outlet in sequence.

[0006] A tube sheet is installed in the middle of the dust collector chamber. Below the tube sheet is a filter bag chamber, in which several filter bags are arranged in a matrix. The upper ends of the filter bags are fixedly connected to the tube sheet. A blowing device is installed above the tube sheet, and the blowing device extends out of the dust collector chamber and is connected to an air manifold. A discharge valve is installed below the bottom hopper of the dust collector chamber.

[0007] An SCR module is installed in the middle of the denitrification chamber. A second blowing device is installed above the SCR module. The pipeline of the second blowing device extends out of the denitrification chamber and is connected to the hot steam main pipe. A rectifier grid is installed above the second blowing device and below the chimney. A discharge valve is installed below the bottom collection chamber of the denitrification chamber.

[0008] Furthermore, the air bag is mounted on the outer wall of the dust collector via an air bag mounting bracket.

[0009] Furthermore, the denitrification chamber and the dust removal chamber are each supported on the ground by a number of symmetrically distributed support legs.

[0010] Furthermore, the structure of the second blowing device is the same as that of the first blowing device, both including a blowing pipe. The feed end of the blowing pipe is equipped with a solenoid valve, and a number of Venturi nozzles are equidistantly arranged at the lower end of the blowing pipe.

[0011] Furthermore, the unloading valve includes a valve body, and a rotating shaft is rotatably disposed in the middle position inside the valve body; one end of the rotating shaft is rotatably disposed in an insertion hole in the inner wall of the valve body, and the other end passes through the valve body and is connected to a worm gear mechanism, the input end of the worm gear mechanism being fixedly connected to a reduction motor; the rotating shaft is provided with a switch door that matches the inner wall of the valve body.

[0012] Furthermore, the bottom of the switch door is integrally formed with symmetrically distributed mounting sleeves, and the mounting sleeves are interference-fitted with the rotating shaft.

[0013] Furthermore, an electric heating device is fitted on the outer wall of the valve body. The electric heating device includes a heating body, an electric heating wire is disposed inside the heating body, and an electrical interface is disposed on the outer wall of the heating body. The electrical interface is electrically connected to the electric heating wire.

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

[0015] This novel low-temperature SCR denitrification equipment employs a blowing device installed above the SCR module to remove ash. The blowing force is strong, effectively removing ash and sticky deposits (such as ABS) from the catalyst channels. Furthermore, the blowing of hot steam softens or partially melts the sticky deposits (such as ABS), making them easier to blow away. In low-temperature SCR, the heat of the steam can also temporarily and locally increase the surface temperature of the catalyst, helping to alleviate the stickiness of ABS. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] Figure 1 This is a cross-sectional view of the novel low-temperature SCR denitrification equipment of this utility model;

[0018] Figure 2 Schematic diagram of the structure of blow-jet device one / blow-jet device two;

[0019] Figure 3 This is a schematic diagram of the unloading valve.

[0020] Figure 4 A sectional view of the discharge valve;

[0021] Explanation of reference numerals in the attached drawings: 1. Support leg; 2. Dust collector housing; 3. Flue gas inlet; 4. Filter bag; 5. Blow-jet device one; 6. Air manifold; 7. Air manifold mounting bracket; 8. Chimney; 9. Denitrification housing; 10. Rectifying grid; 11. SCR module; 12. Blow-jet device two; 13. Hot steam main pipe; 14. Flue gas outlet; 15. Unloading valve one; 16. Unloading valve two;

[0022] 1201. Blow nozzle; 1202. Solenoid valve; 1203. Venturi nozzle;

[0023] 1501, Valve body; 1502, Opening / closing door; 1503, Rotating shaft; 1504, Worm gear mechanism; 1505, Mounting sleeve; 1506, Insertion hole; 1507, Electric heating device. Detailed Implementation

[0024] like Figure 1-4 As shown, a novel low-temperature SCR denitrification device includes a denitrification chamber 9 and a dust collection chamber 2 arranged side by side. The tops of the denitrification chamber 9 and the dust collection chamber 2 are connected together by a chimney 8. The outside of the chimney 8 is covered with an insulation layer to prevent air condensation in low-temperature environments. At the bottom of the denitrification chamber 9 and the dust collection chamber 2, at the ends furthest from each other, are respectively installed a flue gas outlet 14 and a flue gas inlet 3. Flue gas passes sequentially through the flue gas inlet 3, the dust collection chamber 2, the chimney 8, the denitrification chamber 9, and the flue gas outlet 14.

[0025] A tube sheet is installed in the middle of the dust collector housing 2. Below the tube sheet is the filter bag chamber, in which several filter bags 4 are arranged in a matrix. The upper ends of the filter bags 4 are fixedly connected to the tube sheet. The base fabric of the filter bags 4 is preferably made of acid-resistant fiber: P84 (polyimide), PTFE (polytetrafluoroethylene), or fiberglass membrane (requiring special treatment for acid resistance). The surface of the base fabric of the filter bags 4 also requires anti-corrosion treatment: PTFE impregnation or membrane coating, which significantly improves anti-sticking, hydrophobicity, and acid resistance, making it suitable for high-sulfur, high-humidity, and sticky dust treatment, thereby improving the dust removal effect.

[0026] A blower device 5 is installed above the tube sheet. The blower device 5 extends out of the dust collector housing 2 and connects to an air manifold 6. The air manifold 6 is mounted on the outer wall of the dust collector housing 2 via an air manifold mounting bracket 7. The air manifold 6 supplies air for blowing and cleaning of the filter bags 4, preventing clogging and ensuring optimal filtration. A discharge valve 16 is installed below the bottom hopper of the dust collector housing 2; a star-shaped discharge valve, a flap valve, or a slide valve can be selected.

[0027] An SCR module 11 is installed in the middle of the denitrification chamber 9. A second blowing device 12 is installed above the SCR module 11 to purge the mixture of viscous ABS deposits, fly ash, and desulfurization byproducts, preventing blockage of the catalyst channels. The blowing device 12 extends out of the denitrification chamber 9 and is connected to a hot steam main pipe 13. The heat of the hot steam can soften or partially melt highly viscous deposits (such as ABS), making them easier to blow away. In low-temperature SCR, the heat of the steam can also temporarily and locally increase the surface temperature of the catalyst, helping to alleviate the stickiness of ABS.

[0028] A flow-rectifying grid 10 is installed above the second blowing device 12 and below the chimney 8 to ensure uniform distribution of flue gas velocity, temperature, and pollutant concentration, and to avoid local eddies that could lead to ash accumulation or uneven denitrification efficiency.

[0029] A discharge valve 15 is installed below the bottom collection chamber of the denitrification chamber 9. The discharge valve 15 includes a valve body 1501, and a rotating shaft 1503 is rotatably mounted in the middle of the valve body 1501. One end of the rotating shaft 1503 is rotatably installed in an insertion hole 1506 on the inner sidewall of the valve body 1501, and the other end extends out of the valve body 1501 and is connected to a worm gear mechanism 1504. The input end of the worm gear mechanism 1504 is fixedly connected to a reduction motor. A switch door 1502 that matches the inner sidewall of the valve body 1501 is installed on the rotating shaft 1503. The bottom of the switch door 1502 has symmetrically distributed mounting sleeves 1505 integrally formed, and the mounting sleeves 1505 are interference-fitted with the rotating shaft 1503. The worm gear mechanism 1504 drives the rotating shaft 1503 to rotate, thereby realizing the rotation of the door 1502 and thus opening and closing the door 1502.

[0030] ABS (acrylonitrile-butadiene-styrene copolymer) is a viscous substance with strong adhesion at room temperature, easily adhering to the inner wall of valves, sealing surfaces, and transmission components, forming a "gel-like" accumulation. When the mixture flows through the valve, the viscous substance will coat fly ash and desulfurization by-product particles, forming high-viscosity clumps, resulting in a significant increase in resistance when the valve is opened, and even jamming. Therefore, an electric heating device 1507 is sleeved on the outer wall of the valve body 1501. The electric heating device includes a heating body, an electric heating wire installed inside the heating body, and an electrical interface installed on the outer wall of the heating body, which is electrically connected to the electric heating wire. When energized, the electric heating wire generates heat, causing the valve body 1501 to heat up, preventing the ABS from deliquescing and sticking, thereby ensuring the smooth use of the unloading valve 15.

[0031] The denitrification chamber 9 and the dust removal chamber 2 are respectively supported on the ground by a number of symmetrically distributed support legs 1.

[0032] The structure of the second blowing device 12 and the first blowing device 5 is the same, both including a blowing pipe 1201. A solenoid valve 1202 is installed at the feed end of the blowing pipe 1201, and a number of Venturi nozzles 1203 are installed at equal intervals at the lower end of the blowing pipe 1201.

[0033] The inner walls of the aforementioned denitrification chamber 9 and dust removal chamber 2 are coated with high-temperature resistant and corrosion-resistant coatings, such as epoxy phenolic resin and flake resin.

[0034] In another embodiment, a combination of ultrasonic cleaning and steam blowing can be used. Taking the common DC75 diaphragm ultrasonic soot blower as an example, the installation method is to determine the installation position and make a hole on the side wall of the denitrification box 9. The diaphragm ultrasonic soot blower mounting sleeve is inserted and welded to the side wall of the denitrification box 9. The horn extends into the wall about 30mm. The distance between the lower edge of the sound tube and the SCR module is generally between 300-500mm. This allows the sound waves generated by the diaphragm soot blower to effectively act on the catalyst surface, achieving a better cleaning effect.

[0035] The combination of ultrasonic cleaning and steam blowing allows for a systematic cleaning operation through long-term ultrasonic cleaning and periodic steam blowing.

[0036] The operation process of this utility model is as follows:

[0037] First, the flue gas enters the dust removal chamber 2 through the flue gas inlet 3 for dust removal. Then, the filtered flue gas enters the denitrification chamber 9 through the chimney 8 for catalytic reaction to achieve denitrification. Finally, the denitrified flue gas is discharged from the flue gas outlet 14.

[0038] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A novel low-temperature SCR denitrification device, characterized in that: It includes a denitrification chamber (9) and a dust removal chamber (2) arranged side by side. The tops of the denitrification chamber (9) and the dust removal chamber (2) are connected together by a chimney (8). The bottoms of the denitrification chamber (9) and the dust removal chamber (2) are respectively provided with a flue gas outlet (14) and a flue gas inlet (3) at the ends away from each other. The flue gas passes through the flue gas inlet (3), the dust removal chamber (2), the chimney (8), the denitrification chamber (9), and the flue gas outlet (14) in sequence. A tube sheet is provided in the middle of the dust collector box (2). Below the tube sheet is a filter bag chamber, in which several filter bags (4) are arranged in a matrix. The upper end of the filter bags (4) is fixedly connected to the tube sheet. A blowing device (5) is provided above the tube sheet. The blowing device (5) extends out of the dust collector box (2) and is connected to an air tank (6). A discharge valve (16) is provided below the bottom hopper of the dust collector box (2). An SCR module (11) is installed in the middle of the denitrification chamber (9). A second blowing device (12) is installed above the SCR module (11). The pipeline of the second blowing device (12) extends out of the denitrification chamber (9) and is connected to the hot steam main pipe (13). A flow rectifier grid (10) is installed above the second blowing device (12) and below the chimney (8). A discharge valve (15) is installed below the bottom collection chamber of the denitrification chamber (9).

2. The novel low-temperature SCR denitrification equipment according to claim 1, characterized in that: The air bag (6) is mounted on the outer wall of the dust collector (2) via an air bag mounting bracket (7).

3. The novel low-temperature SCR denitrification equipment according to claim 1, characterized in that: The denitrification chamber (9) and the dust removal chamber (2) are supported on the ground by several symmetrically distributed support legs (1).

4. The novel low-temperature SCR denitrification equipment according to claim 1, characterized in that: The structure of the second blowing device (12) and the first blowing device (5) are the same, both including a blowing pipe (1201). The feed end of the blowing pipe (1201) is equipped with a solenoid valve (1202), and a number of Venturi nozzles (1203) are equidistantly arranged at the lower end of the blowing pipe (1201).

5. The novel low-temperature SCR denitrification equipment according to claim 1, characterized in that: The discharge valve (15) includes a valve body (1501), and a rotating shaft (1503) is rotatably disposed in the middle position inside the valve body (1501). One end of the rotating shaft (1503) is rotatably disposed in the insertion hole (1506) on the inner side wall of the valve body (1501), and the other end passes through the valve body (1501) and is connected to a worm gear mechanism (1504). The input end of the worm gear mechanism (1504) is fixedly connected to a reduction motor. A switch door (1502) matching the inner side wall of the valve body (1501) is provided on the rotating shaft (1503).

6. The novel low-temperature SCR denitrification equipment according to claim 5, characterized in that: The bottom of the switch door (1502) is integrally formed with symmetrically distributed mounting sleeves (1505), and the mounting sleeves (1505) are interference-fitted with the rotating shaft (1503).

7. The novel low-temperature SCR denitrification equipment according to claim 5, characterized in that: An electric heating device (1507) is sleeved on the outer wall of the valve body (1501). The electric heating device includes a heating body, an electric heating wire is provided inside the heating body, and an electrical interface is provided on the outer wall of the heating body. The electrical interface is electrically connected to the electric heating wire.

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