Anti-oxidation structure of hot blast stove

Abstract

The utility model provides a kind of hot blast furnace anti-oxidation structure, including furnace body shell, the inner wall of furnace body shell is sequentially provided with heat-insulating refractory layer, framework and anti-oxidation layer from outside to inside, the inside and outside of the framework are provided with the anti-oxidation layer, the upper surface of furnace body shell is connected with air inlet pipe, the framework is provided with air outlet pipe, and the air inlet pipe is connected with the air outlet pipe and is arranged, multiple air outlets are equidistantly opened on the air outlet pipe, the air outlet pipe is mounted and fixed on the framework by connecting piece;The utility model can improve anti-oxidation performance, and maintain furnace air pressure balance.

Description

Technical Field

[0001] This utility model relates to the technical field of hot blast stove equipment, and in particular to an anti-oxidation structure for hot blast stoves. Background Technology

[0002] A hot blast stove is a device that uses the heat generated by fuel combustion to heat air, and then delivers the heated air to the required equipment or location. It is widely used in industries such as metallurgy, chemicals, building materials, and grain drying. During operation, the interior of the stove and components in contact with the high-temperature air are constantly exposed to high temperatures, making them susceptible to oxidation reactions with oxygen in the air. This oxidation corrosion not only reduces the structural strength of the stove but also decreases heat exchange efficiency. In particular, the metal components on the inner wall of the stove will develop oxide scale under high-temperature oxidation. This scale, carried by the hot air, can contaminate the process media, seriously affecting product quality. Furthermore, traditional anti-oxidation measures have significant limitations: single-coating structures are prone to cracking under thermal shock, and the high-temperature airflow accelerates coating peeling; while a completely sealed design reduces oxygen contact, it can lead to pressure imbalance inside the stove, affecting hot air delivery efficiency, and requires frequent disassembly and reassembly of seals during maintenance, increasing operating costs. Summary of the Invention

[0003] In view of this, the purpose of this utility model is to provide an anti-oxidation structure for a hot blast stove that can improve anti-oxidation performance and maintain gas pressure balance inside the furnace.

[0004] This utility model is achieved by the following method: a hot blast stove anti-oxidation structure, including a furnace shell, wherein a heat insulation and refractory layer, a frame and an anti-oxidation layer are arranged sequentially from the outside to the inside of the inner wall of the furnace shell, the anti-oxidation layer is arranged on both the inner and outer sides of the frame, an air inlet pipe is connected to the upper surface of the furnace shell, an air outlet pipe is arranged on the frame, and the air inlet pipe and the air outlet pipe are connected to each other, and multiple air outlets are opened at equal intervals on the air outlet pipe, and the air outlet pipe is installed and fixed on the frame by a connector.

[0005] Furthermore, the material of the heat-insulating refractory layer is high-alumina refractory brick with an Al2O3 content ≥75%, a thickness of 200-300mm, and a compressive strength ≥60MPa.

[0006] Furthermore, the material of the anti-oxidation layer is SiC ceramic matrix composite material or Al2O3-SiO2 composite ceramic material, with a thickness of 10-20mm.

[0007] Furthermore, the connector includes a U-shaped mounting block, a support plate is provided on the top of the frame, an arc-shaped mounting groove for limiting the air outlet pipe is provided on the support plate, extension blocks extend from the outer sides of the two vertical plates of the U-shaped mounting block, the extension blocks are fixed to the support plate by high-temperature resistant bolts, the U-shaped mounting block is sleeved on the air outlet pipe, and a screw is spirally embedded on the horizontal plate of the U-shaped mounting block, and a limiting block for limiting the air outlet pipe is provided at the end of the screw.

[0008] The beneficial effects of this utility model are as follows: This utility model, through a multi-layer composite structure design, sets an anti-oxidation layer on both the inner and outer sides of the frame and cooperates with the airflow balance system of the inlet and outlet pipes, effectively isolates oxygen contact, reduces the risk of oxidation and corrosion, and avoids gas pressure imbalance in the furnace. It has the advantages of improving anti-oxidation performance, reducing structural corrosion, extending service life and maintaining gas pressure balance in the furnace. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of this utility model.

[0010] Figure 2 This is a schematic diagram of the skeleton.

[0011] Figure 3 This is a structural schematic diagram of the connector.

[0012] Figure 4 This is a schematic diagram of the internal structure of this utility model. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings.

[0014] Please see Figures 1 to 4 As shown, this utility model provides an embodiment: a hot blast stove anti-oxidation structure, including a furnace shell 1. The inner wall of the furnace shell 1 is provided with a heat insulation and refractory layer 2, a frame 3 and an anti-oxidation layer 4 from the outside to the inside. The anti-oxidation layer 4 is provided on both the inner and outer sides of the frame 3. An air inlet pipe 5 is connected to the upper surface of the furnace shell 1. An air outlet pipe 6 is provided on the frame 3, and the air inlet pipe 5 is connected to the air outlet pipe 6. Multiple air outlets 61 are opened at equal intervals on the air outlet pipe 6. The air outlet pipe 6 is installed and fixed on the frame 3 by a connector 7.

[0015] The heat-insulating and refractory layer refers to the high-temperature resistant barrier layer located between the inner wall of the outer shell and the frame. It can be made of high-alumina material to reduce the transfer of external heat to the furnace body and lower the operating temperature of the frame and anti-oxidation layer. The frame is the rigid structure that supports the anti-oxidation layer. It can be made of a metal alloy frame to maintain the stability of the internal structure of the furnace body and to provide an installation base for the gas outlet pipe.

[0016] The anti-oxidation layer refers to the anti-oxidation material layer covering the inner and outer surfaces of the skeleton. Specifically, it can be achieved using ceramic matrix composite materials, which are used to directly block oxygen from contacting the metal skeleton and prevent high-temperature oxidation reactions.

[0017] The gas outlet pipe refers to the gas conveying pipeline that runs through the skeleton. Specifically, it can be implemented using segmented high-temperature resistant steel pipes. Its equally spaced gas outlets are used to evenly distribute inert gas and replace residual oxygen in the furnace.

[0018] The connector refers to the installation component that fixes the vent pipe to the frame. Specifically, it can be implemented using a U-shaped structure with extension blocks and limit blocks. The positional stability of the vent pipe in high-temperature environments is ensured by bolt fastening.

[0019] Specifically, the furnace shell serves as the external protective structure, with its inner wall layered with heat-insulating and refractory layers to effectively reduce heat conduction and prevent accelerated oxidation of the furnace frame due to high temperatures. The anti-oxidation layers on both the inner and outer sides of the frame form a double barrier, blocking oxygen penetration from both sides. The inlet pipe guides external inert gas into the outlet pipe, which evenly covers the furnace frame surface through equidistantly distributed outlets, actively replacing oxygen within the furnace. The connectors utilize a U-shaped structure with bolts for fixation, ensuring the stability of the outlet pipe installation under high-temperature expansion and preventing pipe displacement or detachment due to thermal stress.

[0020] Compared with existing technologies, existing coatings rely solely on surface coverage and cannot withstand high-temperature erosion and mechanical wear. This solution, however, combines a double-layer anti-oxidation layer inside and outside the skeleton with active protection using inert gas to form a three-dimensional protection system. Traditional sealing structures passively isolate oxygen, while this solution actively reduces oxygen concentration through gas replacement, fundamentally inhibiting oxidation reactions. The U-shaped limiting structure of the connectors is more adaptable to thermal expansion and contraction in high-temperature environments than traditional welding or clamp fixing, reducing maintenance requirements.

[0021] Through the above technical solutions, this application solves the problem of anti-oxidation failure caused by easy coating peeling, extends the protection life through the synergistic effect of multi-layer structure, overcomes the defect that the sealed structure cannot completely isolate oxygen, and reduces the risk of oxidation by actively replacing it with inert gas; the installation method of the connector avoids the loosening of the pipeline under high temperature environment, ensures the uniformity of gas distribution, and improves the stability of anti-oxidation effect.

[0022] Please continue reading. Figure 4 As shown, in one embodiment of this utility model, the material of the heat-insulating and fire-resistant layer 2 is a high-alumina refractory brick with an Al2O3 content ≥75%, a thickness of 200-300mm, and a compressive strength ≥60MPa.

[0023] High-alumina refractory bricks refer to refractory materials with alumina as the main component. They can be prepared by sintering or electrofusion processes. Their high alumina content can effectively improve the high-temperature resistance of the refractory layer.

[0024] The Al2O3 content ≥75% refers to the mass percentage of alumina in the material, which can be achieved by adjusting the raw material ratio. This content range can balance material cost and high-temperature corrosion resistance.

[0025] The thickness of 200-300mm refers to the vertical dimension of the refractory layer, which can be formed by layered masonry or integral casting. This thickness range can meet the heat insulation requirements while avoiding excessive occupation of the internal space of the furnace.

[0026] Among them, the compressive strength ≥60MPa refers to the load-bearing capacity of the material at room temperature, which can be achieved by optimizing the sintering process. This strength index can ensure the structural stability of the refractory layer under high temperature conditions.

[0027] Specifically, high-alumina refractory bricks, through their high alumina content forming a dense crystalline structure, effectively block direct heat conduction between the outer shell of the hot blast stove and the internal high-temperature airflow under high-temperature conditions. The thickness of the refractory layer is controlled within a specific range to ensure insulation performance while avoiding excessive thickness that would lead to redundant furnace volume. The compressive strength of the material is achieved through optimized particle size distribution and sintering temperature, ensuring the refractory layer remains intact when bearing the structural load of the furnace, preventing a decline in insulation performance due to stress cracking.

[0028] Compared to existing technologies, traditional hot blast stoves mostly use ordinary clay-based refractory materials with an alumina content generally below 50%, making them prone to softening and deformation under long-term high-temperature conditions. High-alumina refractory bricks, by increasing the alumina content, significantly enhance the material's high-temperature volume stability, avoiding insulation layer failure caused by material creep. Furthermore, existing technologies typically use empirically designed refractory layer thicknesses, while this solution optimizes material usage by limiting a specific thickness range, ensuring insulation performance.

[0029] Through the above technical solutions, this application can effectively reduce the thermal load on the furnace shell and prevent the strength of the shell material from decreasing due to high-temperature oxidation. The high-temperature stability of the refractory layer reduces gaps caused by material deformation, blocking the path of oxygen penetration into the furnace body, thereby inhibiting the oxidation and corrosion of metal components. The establishment of the material's compressive strength index further ensures the structural integrity of the refractory layer under long-term thermal shock conditions, extending the overall service life of the hot blast stove.

[0030] Please continue reading. Figure 4 As shown, in one embodiment of this utility model, the material of the anti-oxidation layer 4 is SiC ceramic matrix composite material or Al2O3-SiO2 composite ceramic material, and the thickness is 10-20mm.

[0031] Among them, SiC ceramic matrix composites refer to ceramic materials formed by combining silicon carbide as the matrix with other reinforcing phases. Specifically, this can be achieved by reinforcing the silicon carbide matrix with silicon carbide fibers, and it possesses high-temperature stability and thermal shock resistance. Al2O3-SiO2 composite ceramic materials refer to composite ceramic materials formed by sintering alumina and silicon dioxide. Specifically, this can be achieved by mixing alumina and silicon dioxide in a certain proportion and then sintering at high temperature, and it possesses high density and oxidation resistance.

[0032] The thickness of 10-20mm refers to the thickness range of the anti-oxidation layer. The thickness can be controlled by layer sintering or spraying processes. This range can ensure structural strength while taking into account thermal conductivity.

[0033] Specifically, the anti-oxidation layer utilizes SiC ceramic matrix composites or Al2O3-SiO2 composite ceramic materials, taking advantage of the materials' inherent high-temperature anti-oxidation properties to form a stable oxide film under high-temperature conditions, preventing oxygen from further penetrating into the skeleton or heat-insulating refractory layer. The thickness is controlled within the range of 10-20mm, effectively isolating oxygen from direct contact with high-temperature hot air while avoiding excessive thickness that could lead to thermal stress concentration or increased material costs.

[0034] Compared to existing technologies, current anti-oxidation measures rely on surface coatings, which are prone to peeling off due to high-temperature erosion, leading to protective failure. This solution uses composite ceramic materials as the main structure of the anti-oxidation layer, eliminating the need for surface coatings. The material itself possesses anti-oxidation capabilities, and thickness optimization ensures structural stability, reducing the risk of interlayer delamination due to differences in thermal expansion.

[0035] Through the above technical solution, this application solves the problem of protective failure caused by coating peeling of existing anti-oxidation layers, while avoiding the high maintenance cost of sealed structures. The high-temperature stability of composite ceramic materials directly inhibits oxidation reactions, and the combination of the anti-oxidation layer with the skeleton and heat-insulating refractory layer further reduces oxygen residue, thereby extending the service life of key components of the hot blast stove and ensuring the quality of hot blast.

[0036] Please continue reading. Figure 2 and Figure 3 As shown, in one embodiment of the present invention, the connector 7 includes a U-shaped mounting block 71, a support plate 72 is provided on the top of the frame 3, the support plate 72 is provided with an arc-shaped mounting groove 73 for limiting the air outlet pipe 6, the outer sides of the two vertical plates of the U-shaped mounting block 71 are extended with extension blocks 74, the extension blocks 74 are fixed on the support plate 72 by high-temperature resistant bolts, the U-shaped mounting block 71 is sleeved on the air outlet pipe 6, and a screw 75 is spirally embedded on the horizontal plate of the U-shaped mounting block 71, and a limiting block 76 for limiting the air outlet pipe 6 is provided at the end of the screw 75.

[0037] Among them, the U-shaped mounting block refers to a metal component with a U-shaped cross section, which can be made of high-temperature resistant stainless steel or ceramic matrix composite material. Its U-shaped opening is used to wrap the outer wall of the vent pipe to achieve radial constraint.

[0038] Among them, the arc-shaped mounting groove refers to the semi-circular groove machined on the surface of the support plate. Specifically, it can be achieved by mechanical milling or casting. Its curvature matches the outer diameter of the vent pipe to limit the lateral displacement of the vent pipe.

[0039] The extension block refers to the protruding structure that extends vertically outward from both sides of the U-shaped mounting block. It can be achieved by welding or integral molding and is connected to the support plate by high-temperature resistant bolts to provide axial fixation.

[0040] The limiting block refers to the metal block set at the end of the screw, which can be made of high-hardness alloy material. The contact pressure between the limiting block and the outer wall of the air outlet is adjusted by the screw insertion depth.

[0041] Specifically, the vent pipe is pre-positioned within the arc-shaped mounting groove of the support plate. A U-shaped mounting block fits snugly against the outer wall of the vent pipe from top to bottom. An extension block is locked to the support plate using high-temperature resistant bolts, creating a rigid connection between the U-shaped mounting block and the support plate. After the screws are screwed into the horizontal plate, they push the limiting block against the outer wall of the vent pipe. The clamping force of the limiting block on the vent pipe can be controlled by adjusting the screw depth. This structure, through the dual effects of mechanical constraint and adjustable clamping, ensures that the vent pipe does not shift under thermal expansion or vibration conditions in high-temperature environments.

[0042] Compared to existing technologies, traditional hot blast stove exhaust pipes are mostly fixed by welding or integral casting, which are prone to deformation and cracking under high-temperature thermal stress and cannot be disassembled for maintenance. This solution uses a detachable U-shaped mounting block and bolt connection structure, which allows the exhaust pipe to move slightly axially during thermal expansion to release stress, and enables quick maintenance by replacing high-temperature resistant bolts and limiting blocks. At the same time, the cooperation between the arc-shaped mounting groove and the limiting block significantly reduces the risk of radial movement of the exhaust pipe.

[0043] Through the above technical solution, this application effectively solves the problem of loose connection of the gas outlet pipe caused by thermal deformation in high temperature environment, avoids cracking of the anti-oxidation layer or gas leakage caused by displacement of the gas outlet pipe, and ensures the long-term stable operation of the anti-oxidation structure inside the hot blast furnace.

[0044] The above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall be covered by the present utility model.

Claims

1. An anti-oxidation structure for a hot blast stove, comprising a furnace shell, characterized in that: The inner wall of the furnace shell is provided with a heat insulation and refractory layer, a frame and an anti-oxidation layer from the outside to the inside. The anti-oxidation layer is provided on both the inner and outer sides of the frame. An air inlet pipe is connected to the upper surface of the furnace shell. An air outlet pipe is provided on the frame and the air inlet pipe is connected to the air outlet pipe. Multiple air outlets are opened at equal intervals on the air outlet pipe. The air outlet pipe is installed and fixed on the frame by a connector.

2. The anti-oxidation structure of a hot blast stove according to claim 1, characterized in that: The heat-insulating and refractory layer is made of high-alumina refractory bricks with an Al2O3 content ≥75%, a thickness of 200-300mm, and a compressive strength ≥60MPa.

3. The anti-oxidation structure of a hot blast stove according to claim 1, characterized in that: The anti-oxidation layer is made of SiC ceramic matrix composite material or Al2O3-SiO2 composite ceramic material, with a thickness of 10-20mm.

4. The anti-oxidation structure of a hot blast stove according to claim 1, characterized in that: The connector includes a U-shaped mounting block, a support plate is provided on the top of the frame, an arc-shaped mounting groove for limiting the air outlet pipe is provided on the support plate, extension blocks extend from the outer sides of the two vertical plates of the U-shaped mounting block, the extension blocks are fixed to the support plate by high-temperature resistant bolts, the U-shaped mounting block is sleeved on the air outlet pipe, and a screw is spirally embedded on the horizontal plate of the U-shaped mounting block, and a limiting block for limiting the air outlet pipe is provided at the end of the screw.

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