A composite heat-insulating structure of a soda calcining furnace

Abstract

The utility model relates to calcining furnace heat preservation technical field, and disclose a kind of soda calcining furnace composite heat preservation structure, including inner lining, the outer surface of inner lining is sequentially provided with first composite silicate layer and second composite silicate layer, steel wire hanging ash net is arranged between first composite silicate layer and second composite silicate layer, second composite silicate layer outer surface is sprayed with rigid polyurethane layer, the outer surface of rigid polyurethane layer is provided with shell, use rigid polyurethane as heat preservation material, its density is 35~40kg / m 3 , low to 0.018~0.024W / (m·K) heat conductivity coefficient, can significantly reduce the heat loss in the working process of steam calcining furnace, improve heat preservation energy-saving effect, with excellent moisture-proof waterproof performance, its closed porosity reaches more than 90%, can effectively block air convection;And itself is hydrophobic material, after moisture absorption, will not lead to heat conductivity coefficient increase, can avoid the layer body drop-off problem due to water, ensure that in steam environment or humid working condition, furnace body always maintains low heat conduction characteristic.

Description

Technical Field

[0001] This utility model relates to the field of calcining furnace insulation technology, specifically a composite insulation structure for a soda ash calcining furnace. Background Technology

[0002] Alkali steam calcining furnace is a high-temperature thermal equipment specifically designed for alkaline materials (such as sodium carbonate semi-finished products, sodium bicarbonate, alkaline waste residue, etc.). Its core function is to achieve dehydration, decomposition, and purification of materials through high-temperature calcination, while treating the corrosive alkaline steam generated during the calcination process. It is widely used in fields such as soda ash production, caustic soda preparation, metallurgical dealkali treatment, and environmental solid waste treatment. The heat insulation structure of the furnace wall is the key to the energy saving of the calcining furnace.

[0003] Traditional calcining furnaces employ composite silicate insulation structures, using inorganic minerals such as sepiolite wool, aluminum silicate fiber, and expanded perlite as base materials, combined with high-temperature adhesives to create paste or powder-like insulation materials. After drying, this material forms a closed microporous network structure, characterized by low thermal conductivity (≤0.07W / m·k) and high bonding strength (≥100kPa), making it suitable for environments ranging from -25℃ to 600℃ and widely used in industries such as petrochemicals, power generation, and metallurgy. However, in the field of steam calcining furnaces, even with a 40mm layer of composite silicate coating on the furnace wall, the outer wall still reaches 40-50℃ and is prone to detachment upon contact with water. Glass wool insulation cannot effectively prevent air convection, resulting in poor insulation performance. Therefore, we propose a composite insulation structure for soda ash calcining furnaces. Utility Model Content

[0004] The purpose of this utility model is to provide a composite insulation structure for a soda ash calcining furnace to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a composite insulation structure for a soda ash calcining furnace, comprising an inner lining, wherein a first composite silicate layer and a second composite silicate layer are sequentially disposed on the outer surface of the inner lining, a steel wire mesh is sandwiched between the first composite silicate layer and the second composite silicate layer, a rigid polyurethane layer is sprayed onto the outer surface of the second composite silicate layer, and an outer shell is disposed on the outer surface of the rigid polyurethane layer.

[0006] Preferably, the thickness of the rigid polyurethane layer is 15-20 mm.

[0007] Preferably, the thickness of the first composite silicate layer and the second composite silicate layer is 8-12 mm.

[0008] Preferably, the first composite silicate layer and the second composite silicate layer are composed of composite silicate dry powder, binder, chopped glass fiber, silica micro powder and diluent.

[0009] Preferably, the surface of the wire mesh is coated with a silicate adhesive.

[0010] Preferably, the lining comprises a refractory brick stacking layer formed by stacking high-alumina bricks, and a plurality of sets of anchors are embedded in the outer surface of the refractory brick stacking layer.

[0011] Preferably, the installation spacing of several groups of anchors is ≤300 mm.

[0012] Preferably, ceramic fiber modules are installed on the outer surface of the refractory brick stacking layer using anchors.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention uses rigid polyurethane as the insulation material, with a density of 35-40 kg / m³. 3 With a thermal conductivity as low as 0.018~0.024W / (m・K), it can significantly reduce heat loss during the operation of steam calcining furnace and improve the heat preservation and energy saving effect.

[0014] This material has excellent moisture and water resistance, with a closed-cell rate of over 90%, which can effectively block air convection. As it is a hydrophobic material, it does not increase its thermal conductivity after absorbing moisture, thus avoiding the problem of layer peeling due to water contact. This ensures that the furnace body maintains low thermal conductivity in steam or humid conditions. Attached Figure Description

[0015] Figure 1 A schematic diagram of the overall structure of the composite insulation structure for a soda ash calcining furnace provided by this utility model; Figure 2 Provided by this utility model Figure 1 Enlarged structural diagram at point a; Figure 3 Provided by this utility model Figure 2 Enlarged structural diagram at point b.

[0016] In the diagram: 1. Lining; 11. Refractory brick stacking layer; 12. Ceramic fiber module; 13. Anchor; 2. First composite silicate layer; 3. Steel wire mesh; 4. Second composite silicate layer; 5. Rigid polyurethane layer; 6. Outer shell. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Please see Figures 1-3 As shown, a composite insulation structure for a soda ash calcining furnace includes an inner lining 1. A first composite silicate layer 2 and a second composite silicate layer 4 are sequentially disposed on the outer surface of the inner lining 1. A steel wire mesh 3 is sandwiched between the first composite silicate layer 2 and the second composite silicate layer 4. A rigid polyurethane layer 5 is sprayed onto the outer surface of the second composite silicate layer 4. An outer shell 6 is disposed on the outer surface of the rigid polyurethane layer 5.

[0019] Polyurethane raw material is sprayed onto the outer surface of the second composite silicate layer 4 using a high-pressure spraying method, and after it dries and solidifies, a rigid polyurethane layer 5 is formed.

[0020] First, a first composite silicate layer 2 is sprayed onto the inner lining 1 to form a first composite silicate layer 2. Taking advantage of its high temperature resistance and strong adhesion, the strength after solidification is improved. A steel wire mesh 3 is sandwiched between the first composite silicate layer 2 and the second composite silicate layer 4 to increase the overall strength.

[0021] Rigid polyurethane is used as the insulation material, with a density of 35–40 kg / m³. 3 With a thermal conductivity as low as 0.018~0.024W / (m・K), it can significantly reduce heat loss during the operation of steam calcining furnace and improve the heat preservation and energy saving effect.

[0022] This material has excellent moisture and water resistance: the closed-cell rate is over 90%, which can effectively block air convection; and it is a hydrophobic material, so it will not increase its thermal conductivity after absorbing moisture, which can avoid the problem of layer peeling due to water contact, and ensure that the furnace body always maintains low thermal conductivity in steam environment or humid conditions.

[0023] In this embodiment, the thickness of the rigid polyurethane layer 5 is 15-20 mm to meet the heat insulation requirements of the outer layer (temperature ≤150℃) of the soda ash calcining furnace.

[0024] In this embodiment, the thickness of the first composite silicate layer 2 and the second composite silicate layer 4 is 8-12 mm, and the two layers are of the same thickness to balance the thermal insulation performance and the requirement for lightweight structure.

[0025] In this embodiment, the first composite silicate layer 2 and the second composite silicate layer 4 are made of a fiber slurry prepared by mixing composite silicate dry powder, binder, chopped glass fiber, silica micro powder, and diluent. The first composite silicate layer 2 is sprayed onto the outer surface of the ceramic fiber module 12 after high-pressure atomization of the fiber slurry through a fan-shaped nozzle. The second composite silicate layer 4 is sprayed onto the outer surface of the wire mesh 3 after high-pressure atomization of the fiber slurry through a fan-shaped nozzle. After solidification, the second composite silicate layer 4 is formed. The fan-shaped nozzle (diameter 8-10mm) has a spraying pressure of 0.7MPa.

[0026] In this embodiment, the surface of the wire mesh 3 is coated with a silicate adhesive, which strengthens the connection between the wire mesh 3 and the first composite silicate layer 2 and the second composite silicate layer 4.

[0027] In this embodiment, the inner lining 1 includes a refractory brick stacking layer 11 formed by stacking high alumina bricks, and a number of sets of anchors 13 are embedded in the outer surface of the refractory brick stacking layer 11.

[0028] High-alumina bricks are made by mixing first-grade bauxite with phosphoric acid / phosphate binder, forming the mixture, and then sintering it.

[0029] In this embodiment, the installation spacing of several sets of anchors 13 is ≤300 mm, and ceramic fiber modules 12 are installed on the outer surface of the refractory brick stacking layer 11 using anchors 13 to prevent the ceramic fiber modules 12 from falling off.

[0030] The ceramic fiber module 12 is pre-compressed and formed from ceramic fiber blankets. The ceramic fiber module 12 is installed using anchors 13. It has the advantages of being lightweight, having low thermal conductivity, and being resistant to thermal shock, and can be adapted to the complex curved surface of the furnace body.

[0031] Working principle: Rigid polyurethane is used as the insulation material, with a density of 35–40 kg / m³. 3 With a thermal conductivity as low as 0.018~0.024W / (m・K), it can significantly reduce heat loss during the operation of steam calcining furnace and improve the heat preservation and energy saving effect.

[0032] This material has excellent moisture and water resistance: the closed-cell rate is over 90%, which can effectively block air convection; and it is a hydrophobic material, so it will not increase its thermal conductivity after absorbing moisture, which can avoid the problem of layer peeling due to water contact, and ensure that the furnace body always maintains low thermal conductivity in steam environment or humid conditions.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A composite insulation structure for a soda ash calcining furnace, comprising an inner lining (1), characterized in that, The outer surface of the liner (1) is provided with a first composite silicate layer (2) and a second composite silicate layer (4) in sequence. A steel wire mesh (3) is sandwiched between the first composite silicate layer (2) and the second composite silicate layer (4). The outer surface of the second composite silicate layer (4) is sprayed with a rigid polyurethane layer (5). The outer surface of the rigid polyurethane layer (5) is provided with an outer shell (6).

2. The composite insulation structure for a soda ash calcining furnace according to claim 1, characterized in that: The thickness of the rigid polyurethane layer (5) is 15-20 mm.

3. The composite insulation structure for a soda ash calcining furnace according to claim 1, characterized in that: The thickness of the first composite silicate layer (2) and the second composite silicate layer (4) is 8-12 mm.

4. The composite insulation structure for a soda ash calcining furnace according to claim 1, characterized in that: The surface of the wire mesh (3) is coated with a silicate adhesive.

5. The composite insulation structure for a soda ash calcining furnace according to claim 1, characterized in that: The lining (1) includes a refractory brick stacking layer (11) formed by stacking high alumina bricks, and a number of sets of anchors (13) are embedded in the outer surface of the refractory brick stacking layer (11).

6. The composite insulation structure for a soda ash calcining furnace according to claim 5, characterized in that: The installation spacing of several sets of anchors (13) is ≤300 mm.

7. The composite insulation structure for a soda ash calcining furnace according to claim 6, characterized in that: Ceramic fiber modules (12) are installed on the outer surface of the refractory brick stack layer (11) using anchors (13).

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