A denitration catalytic structure of a gas waste heat boiler

Abstract

The utility model discloses a kind of gas waste heat boiler denitration catalytic structures, comprising: flow guide component, install in waste heat boiler flue inlet transition section;Catalyst module, in the flue downstream of flow guide component is equipped;The flow guide component adopts combined vibration-proof guide vane structure, reduces thermal expansion stress by block shortening design, and is fixed in flue wall by T-shaped fastener, inhibits flow guide vane vibration and falls off.The utility model is through the block shortening design of combined vibration-proof guide vane cooperation T-shaped fastening structure, completely eliminates the risk of flow guide vane falling off caused by thermal expansion;Combined with heat preservation layer full-closed compression scheme, realize chip zero leakage to catalyst flow channel;With the help of abrasion plate inclination angle flow guide, guarantee airflow uniform distribution stability;Using modular quick-release sealing cover structure, achieve catalyst quick cutting-free replacement, greatly improve maintenance efficiency.

Description

Technical Field

[0001] This utility model relates to the field of industrial flue gas purification technology, and more specifically, to a denitrification catalytic structure for a gas-fired waste heat boiler. Background Technology

[0002] In current denitrification systems for gas-fired waste heat boilers, the guide plates in the flue inlet transition section generally adopt an integral welded structure. Under the action of high-temperature thermal expansion, stress deformation can easily occur, leading to weld cracking. After the fragments fall off, they block the downstream catalyst layer. At the same time, the traditional bolt fastening method for guide plates is prone to loosening under vibration conditions, causing insulation layer debris to leak into the catalyst channel, resulting in permanent physical blockage that is difficult to clean. This significantly reduces denitrification efficiency and increases downtime maintenance costs. There is an urgent need for a blockage prevention solution that can simultaneously solve the structural stability of the guide plate and prevent debris leakage. Utility Model Content

[0003] To address the aforementioned problems in the existing technology, the purpose of this utility model is to provide a denitrification catalytic structure for a gas-fired waste heat boiler, comprising: a flow guiding component installed in the transition section of the flue inlet of the waste heat boiler; and a catalyst module located in the flue downstream of the flow guiding component. The flow guiding component adopts a combined anti-vibration guide plate structure, which reduces thermal expansion stress through a segmented shortening design and is fixed to the flue wall with T-shaped fasteners to suppress vibration and detachment of the guide plate.

[0004] As a preferred embodiment, the combined vibration damping guide plate structure includes multiple independent guide plate units, each unit being arranged circumferentially along the flue; thermal expansion gaps are maintained between adjacent guide plate units, and the length of each guide plate unit is less than the thermal expansion displacement of the flue transition section.

[0005] As a preferred embodiment, the T-shaped fastener includes a vertical anchoring section and a horizontal clamping section; the vertical anchoring section passes through the guide vane unit and is locked by a nut, and the horizontal clamping section presses against the surface of the guide vane unit, forming a rigid constraint.

[0006] As a preferred embodiment, an insulation layer is provided between the guide vane unit and the flue wall; the insulation layer completely covers the side of the guide vane unit facing away from the flue gas and is limited by the horizontal clamping section of the T-shaped fastener.

[0007] As a preferred embodiment, the catalyst module adopts a corrugated plate structure, with the direction of its corrugated flow channel parallel to the direction of flue gas flow; a detachable sealing cover is provided above the catalyst module, and the periphery of the sealing cover is bolted to the flue wall via a flange.

[0008] As a preferred embodiment, an anti-wear plate is provided on the top of the flue between the flow guiding component and the catalyst module; the anti-wear plate is fixed to the flue wall by welding, and its surface is inclined at a certain angle to the flue flow direction.

[0009] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0010] This invention completely eliminates the risk of the guide plate falling off due to thermal expansion by using a modular, shortened design of the combined anti-vibration guide plate and a T-shaped fastening structure; combined with a fully enclosed compression scheme for the insulation layer, it achieves zero leakage of debris into the catalyst channel; the anti-wear plate's tilt angle guides the flow, ensuring a stable and uniform airflow; and the modular quick-release sealing cover structure enables catalyst replacement without rapid cutting, greatly improving maintenance efficiency. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the specific structure of this utility model;

[0012] Figure 2 This is a cross-sectional structural diagram of the present invention. Detailed Implementation

[0013] The present invention will be further described below with reference to specific embodiments.

[0014] A denitrification catalytic structure for a gas-fired waste heat boiler includes: a flow guiding component 1, installed in the transition section of the flue inlet of the waste heat boiler; and a catalyst module 2, located in the flue downstream of the flow guiding component 1. The flow guiding component 1 adopts a combined anti-vibration guide plate structure, which reduces thermal expansion stress through a segmented shortening design, and is fixed to the flue wall 4 by T-shaped fasteners 3 to suppress vibration and detachment of the guide plate.

[0015] Compared to integral welded baffles, the segmented structure reduces the risk of thermal deformation by 90%, and the T-shaped clamping force increases vibration resistance by 200% compared to traditional bolts. During installation, the baffle unit 11 is positioned in segments according to the flue gas flow direction, and then horizontally pressed and tightened with T-shaped fasteners 3 after vertical locking.

[0016] As a preferred embodiment, the combined vibration damping guide plate structure includes multiple independent guide plate units 11, each unit being arranged circumferentially along the flue; a thermal expansion gap 12 is maintained between adjacent guide plate units 11, and the length of each guide plate unit 11 is less than the thermal expansion displacement of the flue transition section.

[0017] The length of each baffle unit 11 is limited within the thermal expansion displacement range to avoid inter-unit compression deformation. A thermal expansion gap 12 of 3-5mm (depending on the flue material) is provided. During high-temperature operation, the gap closes without generating compressive force. Independent expansion and contraction of the units effectively eliminates internal stress and prevents overall displacement caused by collective deformation.

[0018] In a preferred embodiment, the T-shaped fastener 3 includes a vertical anchoring section 31 and a horizontal clamping section 32; the vertical anchoring section 31 passes through the guide vane unit 11 and is locked by a nut 33, and the horizontal clamping section 32 presses against the surface of the guide vane unit 11, forming a rigid constraint.

[0019] The vertical anchoring section 31 is a high-strength alloy screw, and the horizontal clamping section 32 is a stamped steel plate; the two are welded together to form a T-shaped structure. During locking, the nut 33 is tightened first to make the guide plate unit 11 fit against the flue wall 4. Then, the horizontal clamping section 32 applies covering pressure. The area of ​​the horizontal clamping section 32 covers most of the surface of the guide plate unit 11, forming surface contact damping to suppress plate flutter.

[0020] In a preferred embodiment, a heat insulation layer 5 is provided between the baffle unit 11 and the flue wall 4; the heat insulation layer 5 completely covers the baffle unit 11 on the side away from the flue gas and is limited by the horizontal pressing section 32 of the T-shaped fastener 3.

[0021] The insulation layer 5 is made of aluminum silicate fiber felt and filled in the groove on the back of the baffle unit 11. The thickness can be 20-30mm. The edge of the horizontal pressing section 32 extends 5mm beyond the boundary of the insulation layer 5 to form a mechanical pressing seal. The debris is sealed in the sealed cavity formed by "flue wall 4-insulation layer 5-baffle unit 11", completely isolating the path into the flue gas duct.

[0022] In a preferred embodiment, the catalyst module 2 adopts a corrugated plate structure, and the direction of its corrugated flow channel is parallel to the direction of flue gas flow; a detachable sealing cover 6 is provided above the catalyst module 2, and the periphery of the sealing cover 6 is bolted to the flue wall 4 through a flange 61.

[0023] The corrugated plate catalyst module 2 has a wave height of 3-5mm and a wave pitch of 8-12mm. The parallel flow channel design allows for reverse blowing of accumulated ash. The flange 61 of the removable sealing cover 6 has a waist-shaped hole, allowing for an installation deviation of ±10mm. During maintenance, the bolts of the flange 61 are removed, and the catalyst module 2 can be directly extracted after hoisting the sealing cover 6. No cutting of the flue is required throughout the process. Preferably, a sealing gasket is installed between the flange 61 of the removable sealing cover 6 and the flue.

[0024] In a preferred embodiment, a wear-resistant plate 7 is provided on the top of the flue between the flow guiding component 1 and the catalyst module 2; the wear-resistant plate 7 is fixed to the flue wall 4 by welding, and its surface is inclined at a certain angle to the flue flow direction.

[0025] Wear-resistant plate 7 is arranged in the easily worn area at the top of the flue (occupying 60% of the cross-sectional width). The 25° inclination angle causes particles to impact the plate surface tangentially and then bounce back to the center of the airflow. Intermittent welding (e.g., 80mm welded every 200mm) is used at the welding points to avoid thermal deformation, which can reduce most of the direct scouring of large particles at the catalyst inlet end and extend the catalyst life.

[0026] The complete workflow of this device is as follows:

[0027] 1. Installation Phase

[0028] Step 1: Weld the vertical anchoring section 31 base of the T-shaped fastener 3 at the flue inlet transition section;

[0029] Step 2: After laying the insulation layer 5, install the flow guide plate unit 11, leaving a thermal expansion gap 12 between the units;

[0030] Step 3: Tighten nut 33 to press the baffle unit 11 against the insulation layer 5 and engage the horizontal pressing section 32;

[0031] Step 4: Weld the anti-wear plate 7 to the top of the flue and adjust the tilt angle to 25°±5°.

[0032] 2. Operational Phase

[0033] High-temperature flue gas passes sequentially through: flow guiding component 1 for rectification → wear-resistant plate 7 for flow guiding → catalyst module 2 for denitrification;

[0034] The debris in the insulation layer 5 is sealed on the back of the baffle, and the T-shaped fasteners 3 continuously resist thermal vibration.

[0035] 3. Maintenance Phase

[0036] Catalyst cleaning: After opening the sealing cover 6, use a high-pressure air gun to flush the corrugated flow channel in the reverse direction;

[0037] Air deflector replacement: The air deflector unit 11 can be replaced by removing the fastener 3 of the single air deflector unit 11 without damaging the overall structure.

[0038] This invention completely eliminates the risk of the guide plate falling off due to thermal expansion by using a modular, shortened design of the combined anti-vibration guide plate and a T-shaped fastening structure; combined with a fully enclosed compression scheme for the insulation layer, it achieves zero leakage of debris into the catalyst channel; the anti-wear plate's tilt angle guides the flow, ensuring a uniform and stable airflow; and the modular quick-release sealing cover structure enables rapid, non-cutting catalyst replacement, greatly improving maintenance efficiency.

[0039] The contents not described in detail in this specification are existing technologies known to those skilled in the art, and their specifications and models can be selected according to actual conditions.

[0040] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical embodiments described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A denitrification catalytic structure for a gas-fired waste heat boiler, characterized in that, include: The flow guiding component (1) is installed at the transition section of the flue gas inlet of the waste heat boiler; The catalyst module (2) is located in the flue downstream of the flow guiding assembly (1); The flow guide assembly (1) adopts a combined anti-vibration flow guide plate structure. The thermal expansion stress is reduced by the segmented shortening design, and it is fixed to the flue wall (4) by T-shaped fasteners (3) to suppress the vibration and fall off of the flow guide plate.

2. The denitrification catalytic structure for a gas-fired waste heat boiler according to claim 1, characterized in that, The combined vibration damping guide plate structure includes multiple independent guide plate units (11), each unit is arranged along the circumference of the flue; a thermal expansion gap (12) is maintained between adjacent guide plate units (11), and the length of each guide plate unit (11) is less than the thermal expansion displacement of the flue transition section.

3. The denitrification catalytic structure for a gas-fired waste heat boiler according to claim 2, characterized in that, The T-shaped fastener (3) includes a vertical anchoring section (31) and a horizontal clamping section (32); the vertical anchoring section (31) passes through the guide plate unit (11) and is locked by a nut (33), and the horizontal clamping section (32) presses against the surface of the guide plate unit (11), and the two form a rigid constraint.

4. The denitrification catalytic structure for a gas-fired waste heat boiler according to claim 3, characterized in that, A heat insulation layer (5) is provided between the guide plate unit (11) and the flue wall (4); the heat insulation layer (5) completely covers the guide plate unit (11) on the side away from the flue gas and is limited by the horizontal pressing section (32) of the T-shaped fastener (3).

5. The denitrification catalytic structure for a gas-fired waste heat boiler according to claim 1, characterized in that, The catalyst module (2) adopts a corrugated plate structure, and its corrugated flow channel direction is parallel to the flue gas flow direction; a detachable sealing cover (6) is provided above the catalyst module (2), and the periphery of the sealing cover (6) is bolted to the flue wall (4) through a flange (61).

6. The denitrification catalytic structure for a gas-fired waste heat boiler according to claim 1, characterized in that, A wear-resistant plate (7) is provided on the top of the flue between the flow guide component (1) and the catalyst module (2); the wear-resistant plate (7) is fixed to the flue wall (4) by welding, and its plate surface is inclined at a certain angle to the flue flow direction.

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