Steel rolling heating furnace heat storage honeycomb body integrated with fins for heat exchange enhancement and provided with positioning connection

Abstract

The invention discloses a steel rolling heating furnace heat storage honeycomb body integrated with fins for heat exchange enhancement and provided with positioning connection, the heat storage honeycomb body is composed of a plurality of hexagonal heat storage single bodies, each heat storage single body comprises a hexagonal hollow honeycomb body base body, and the fins are distributed on the outer side wall of the honeycomb body base body. The heat storage capacity is improved by increasing the fins to increase the specific surface area.

Description

Technical Field

[0001] This invention discloses a heat storage honeycomb structure for a steel rolling furnace with integrated finned heat exchange and positioning connection. Background Technology As a critical thermal equipment widely used in industrial production and consuming enormous amounts of energy, the operating efficiency, energy structure, and emission levels of heating furnaces directly affect the progress of achieving the "dual carbon" (carbon dioxide, carbon sequestration, and carbon emissions) goals. Currently, to improve thermal efficiency and reduce energy consumption, most heating furnaces are regenerative furnaces. Therefore, the efficient and stable operation of the regenerator is crucial. Most regenerators currently used in regenerative furnaces primarily employ honeycomb structures made of high-alumina or mullite materials. Common problems encountered during the use of regenerators include melting, softening, cracking, blockage, and corrosion. Poor thermal shock resistance of the regenerator material is particularly prevalent, and the causes of these problems are closely related to the materials used in the regenerator and flow deviation issues. Since honeycomb structures operate in harsh environments with rapid heating and cooling or corrosive gases for extended periods, stringent requirements are placed on the materials used in the regenerator.

[0002] In high-temperature industrial furnaces such as steel rolling heating furnaces, regenerative combustion systems achieve waste heat recovery (>80%) by periodically switching the flow of flue gas and air through the regenerator, significantly reducing fuel consumption. Honeycomb regenerators have become the mainstream material due to their high specific surface area and low resistance characteristics, and their performance directly affects system energy efficiency. However, traditional honeycomb regenerators (such as cordierite and silicon carbide) rely on smooth pore walls for heat transfer, resulting in predominantly laminar airflow, high boundary layer thermal resistance, and Nusselt numbers (Nu) generally below 5. Although increasing pore density can improve the surface area, it leads to a sharp increase in pressure loss, limiting the overall improvement in heat transfer coefficient and restricting the potential for waste heat recovery. Summary of the Invention

[0003] To overcome the above-mentioned defects, the present invention aims to provide a heat storage honeycomb structure for a steel rolling heating furnace with integrated finned heat exchange and positioning connection.

[0004] To achieve the above objectives, the present invention provides a heat storage honeycomb structure for a rolling mill heating furnace with integrated finned enhanced heat exchange and positioning connection. The heat storage honeycomb structure is composed of a plurality of hexagonal heat storage cells, each heat storage cell comprising: A hexagonal hollow honeycomb substrate, with fins arranged on the outer side wall of the honeycomb substrate.

[0005] Furthermore, the fins are truncated conical columns.

[0006] Furthermore, the fins are connected to the hexagonal hollow honeycomb substrate via a gradient functional transition layer, wherein the gradient functional transition layer is FeCrAl / Al2O3.

[0007] Furthermore, the ends of the corresponding fins on two adjacent heat storage units abut each other.

[0008] Furthermore, the heat storage honeycomb body is a cuboid; an upper tenon is provided at the upper end of one side of the cuboid, and a lower mortise is provided at the lower end of the cuboid on the same side; an upper mortise is provided at the upper end of the other side of the cuboid, and a lower tenon is provided at the lower end of the cuboid on the same side; the upper heat storage honeycomb body is engaged with the upper tenon and upper mortise at the upper end of the lower heat storage honeycomb body through the lower mortise and lower tenon at the lower end.

[0009] Furthermore, through-holes are distributed on the sidewalls of the honeycomb matrix.

[0010] Furthermore, the hexagonal hollow honeycomb matrix is ​​made of cordierite, mullite, or silicon carbide ceramic material, with a pore density of 200-400 cpsi.

[0011] Furthermore, the depth of the mortise is 10%-20% of the thickness of the honeycomb structure.

[0012] The present invention has the following advantages: 1) Significantly improves heat transfer efficiency: The fin structure greatly enhances airflow turbulence and heat transfer boundary layer disturbance. Tests have verified that the overall heat transfer coefficient (Nusser number or convective heat transfer coefficient) is improved by up to 178%.

[0013] 2) Ensure high-temperature sealing: Individual honeycomb heat storage units are connected by dovetail joints, and the tenons and mortises of adjacent honeycomb units form a mechanical interlock. This ensures the unobstructed flow of the channels, thereby reducing dust accumulation and blockage.

[0014] 3) It has excellent thermal expansion self-compensation capability and can maintain extremely high connection airtightness under high temperature thermal cycling, with gas leakage rate stably controlled below 0.5% (vol%).

[0015] 4) Extended service life: The gradient transition layer protects the fins, and the tenon and mortise structure resists thermal stress damage, which together significantly improves the durability of the heat storage body under harsh working conditions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the honeycomb structure of the present invention.

[0017] Figure 2 This is a planar schematic diagram of the honeycomb structure of the present invention.

[0018] Figure 3 This is a schematic diagram of the structure of the honeycomb substrate of the present invention.

[0019] Figure 4 This is a planar schematic diagram of the honeycomb substrate of the present invention.

[0020] Figure 5 This is a schematic diagram of the fin structure of the honeycomb structure of the present invention.

[0021] Figure 6 yes Figure 1 Enlarged schematic diagram of the connection of the three heat storage units.

[0022] Among them, (1) is a honeycomb heat storage body, (1-1) is a honeycomb substrate; (2) is a longitudinal toothed fin; (2-1) is a FeCrAl / Al2O3 gradient functional transition layer, (2-1-1) is a FeCrAl layer, (2-1-2) is an Al2O3 layer; (2-2) is a nickel-based high-temperature alloy layer; (3-1) is a tenon, and (3-2) is a mortise. Detailed Implementation

[0023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] like Figures 1 to 6As shown, the integrated finned heat exchange heat storage honeycomb structure for a steel rolling furnace with positioning connection of the present invention is composed of several hexagonal heat storage units. Each heat storage unit includes a hexagonal hollow honeycomb base, on which fins are arranged on the outer side wall. The shape and structure of the fins can be set as needed, such as triangular prisms, cylinders, polygonal columns, etc. Preferably, as shown in the figure, the fins are truncated conical columns.

[0028] As shown in the figure, longitudinal toothed fins (2) are integrally provided on the outer wall surface of the honeycomb (1) channel. The fins are made of nickel-based high-temperature alloy material and are firmly bonded to the honeycomb substrate (1-1) through FeCrAl / Al2O3 gradient functional transition layer (2-2), which effectively suppresses high-temperature oxidation and interfacial thermal stress. In addition, the distribution density of the fins is proportional to the distance from the inner wall of the furnace, thereby effectively improving the heat storage efficiency. The increase of fins increases the specific surface area to improve the heat storage capacity. The longitudinal toothed fins (2) are made of nickel-based high-temperature alloy material and are firmly bonded to the honeycomb substrate (1-1) through FeCrAl / Al2O3 gradient functional transition layer (2-1). The thickness of the FeCrAl / Al2O3 gradient functional transition layer (2-1) is 50-200μm, in which the FeCrAl layer (2-1-1) is adjacent to the honeycomb substrate (1-1) and the Al2O3 layer (2-1-2) is adjacent to the longitudinal toothed fins (2). This can effectively suppress high-temperature oxidation and interfacial thermal stress.

[0029] Furthermore, the heat exchange process within the regenerator occurs during the flue gas exhaust stage, where the flue gas stores sensible heat in the honeycomb structure as it flows through it, heating the honeycomb structure. During the combustion stage, the air (or gas) is heated as it flows through the honeycomb structure, and the residual heat is carried back into the furnace. In these stages, if the gas flow is skewed within the regenerator, after several reversals, it can easily lead to localized high temperatures in the honeycomb structure, generating thermal stress. When the generated temperature stress exceeds its withstand limit, the honeycomb structure will crack. Therefore, the dovetail tenon and mortise connection structure (3) allows individual honeycomb structures (1) to be tightly assembled together, ensuring consistent alignment of the channels. Dovetail tenon joints (3) are set on the upper and lower surfaces of the honeycomb body (1). The four corners of the upper and lower surfaces of the honeycomb body correspond to tenons (3-1) and mortises (3-2) respectively. The inclination angle of the tenon (3-1) in the dovetail tenon joint is 30°, and the depth of the mortise (3-2) is 10%-20% of the thickness of the honeycomb body (1). The height of the tenon (3-1) is the same as the depth of the mortise (3-2), and the cross-sectional profile of the tenon (3-1) is trapezoidal or right-angled sector. The extension direction of the tenon structure is parallel to the direction of the honeycomb body channel. This can minimize the occurrence of flow deviation.

[0030] In summary, this invention can be widely applied to high-temperature regenerative combustion systems such as steel rolling heating furnaces. By significantly improving the heat exchange efficiency and connection reliability of the regenerator, it effectively enhances the overall thermal efficiency of the heating furnace, significantly reduces fuel consumption, and extends the service life of the regenerator and the system, thus possessing significant energy-saving, consumption-reducing, and economic value.

[0031] The present invention has been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described above. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Many other changes and modifications made without departing from the concept and scope of the present invention should be considered within the scope of protection of the present invention.

[0032] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0033] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A heat storage honeycomb structure for a steel rolling heating furnace with integrated finned enhanced heat transfer and positioning connection, characterized in that, The heat storage honeycomb structure is composed of several hexagonal heat storage cells, each heat storage cell comprising: A hexagonal hollow honeycomb substrate, with fins arranged on the outer side wall of the honeycomb substrate.

2. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 1, characterized in that, The fins are truncated conical columns.

3. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 2, characterized in that, The fins are connected to the hexagonal hollow honeycomb matrix through a gradient functional transition layer, wherein the gradient functional transition layer is FeCrAl / Al2O3.

4. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 1, characterized in that, The ends of the corresponding fins on two adjacent heat storage units abut each other.

5. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 1, characterized in that, The heat storage honeycomb body is a cuboid; an upper tenon is provided at the upper end of one side of the cuboid, and a lower mortise is provided at the lower end of the cuboid on the same side; an upper mortise is provided at the upper end of the other side of the cuboid, and a lower tenon is provided at the lower end of the cuboid on the same side; the upper heat storage honeycomb body is engaged with the upper tenon and upper mortise at the upper end of the lower heat storage honeycomb body through the lower mortise and lower tenon at the lower end.

6. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 1, characterized in that, The honeycomb matrix has through-holes distributed on its sidewalls.

7. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 1, characterized in that, The hollow honeycomb matrix is ​​made of cordierite, mullite, or silicon carbide ceramic material, with a pore density of 200-400 cpsi.

8. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 5, characterized in that, The depth of the mortise is 10%-20% of the thickness of the honeycomb structure.

9. The integrated finned heat exchange enhanced heat transfer regenerator honeycomb structure for a steel rolling furnace with positioning connection as described in claim 5, characterized in that, The fins are made of nickel-based high-temperature alloy.

Images