Hot-state repairing material composite ceramic fiber blanket and hot-state repairing construction method thereof

Abstract

The present application belongs to the technical field of refractory materials, and discloses a hot-state repairing material composite ceramic fiber blanket and a hot-state repairing construction method thereof. The hot-state repairing material composite ceramic fiber blanket comprises, from top to bottom, an upper layer, a filling layer and a bottom layer; a plurality of staggered partition cloths are arranged between the upper layer and the bottom layer, the partition cloths are vertically arranged to form a net structure to divide the filling layer into a plurality of small cells, and the hot-state repairing material is filled in the small cells; and the upper layer, the bottom layer and the partition cloths are all ceramic fiber cloths. The hot-state repairing material is combined with the ceramic refractory fiber, the hot-state repairing material is filled in the small cells in the ceramic fiber blanket through structural design, the ceramic fiber blanket is used during transportation and construction, the advantages of the fiber blanket, such as high integrity and fast construction, are fully exerted, the ceramic fiber blanket is converted into a hard overall furnace lining after construction and sintering, and the fast sintering repairing performance of the hot-state repairing material is exerted.

Description

Technical Field

[0001] This invention belongs to the field of refractory materials technology, specifically relating to a hot-state repair material composite ceramic fiber blanket and its hot-state repair construction method. Background Technology

[0002] During the operation of high-temperature industrial kilns and equipment, the lining material is subjected to high temperatures, atmospheres, and molten slag, which can cause cracking and detachment after prolonged service. To minimize operational losses due to shutdowns for maintenance, emergency repairs under hot conditions are necessary. Conventional methods include: placing hot repair material into the furnace at a relatively high temperature, allowing it to liquefy, self-level, and then sintering to repair the lining; alternatively, lowering the temperature to a certain level and then using non-baking ramming mix or dry mix for ramming repairs; or hot spraying.

[0003] All of the above construction methods involve transporting the unshaped refractory material to the site, mixing it thoroughly, and then applying it. During transportation, hot repair materials and hot spraying materials may segregate due to vibration, requiring on-site remixing. However, on-site mixing generates excessive dust, causing environmental pollution. Furthermore, hot repair materials are difficult to spread evenly when liquefied and flowing in the furnace for repair, and the material layer is prone to lifting and falling off when under-sintered, while the material layer is difficult to clean when over-sintered. Hot spraying materials have a high construction rebound rate, wasting material, and the rebounded material is difficult to clean completely. No-bake ramming materials may dry out due to long transportation and storage times, making them difficult to ram and dense, and requiring high labor intensity during ramming. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the shortcomings of the existing technology by providing a hot-state repair material composite ceramic fiber blanket and its hot-state repair construction method. During transportation and construction, it is a ceramic fiber blanket, which fully utilizes the advantages of strong integrity and quick construction of the fiber blanket. After construction, it is sintered and cured to become a hard integral furnace lining, thus giving full play to the rapid sintering repair performance of the hot-state repair material.

[0005] To solve the technical problem proposed in this invention, this invention provides a hot-state repair material composite ceramic fiber blanket, which includes an upper layer, a filling layer and a bottom layer from top to bottom; a number of staggered partition fabrics are provided between the upper layer and the bottom layer, and the vertically arranged partition fabrics form a mesh structure that divides the filling layer into a number of small grids, and the small grids are filled with hot-state repair material.

[0006] In the above scheme, the thickness of the upper layer is ≤5mm, preferably ≤1mm.

[0007] In the above scheme, the thickness of the bottom layer is ≤5mm, preferably ≤1mm.

[0008] In the above scheme, the thickness of the separating cloth is ≤1mm, preferably 0.2-0.5mm.

[0009] In the above scheme, the upper layer, the lower layer, and the separator fabric are all ceramic fiber fabrics.

[0010] Furthermore, the ceramic fiber cloth is woven from one or more of aluminosilicate refractory fibers and zirconium-containing aluminosilicate refractory fibers.

[0011] Furthermore, the upper and lower ceramic fiber cloths are pre-impregnated or sprayed with liquid organic aluminum, and active magnesium oxide powder is sprayed on them before the liquid organic aluminum solidifies.

[0012] Furthermore, the liquid organoaluminum is an aluminum isopropoxide melt at a temperature of 120-135°C, or a saturated solution of aluminum formate or aluminum acetate at room temperature.

[0013] Furthermore, the particle size of the activated magnesium oxide powder is <200 mesh.

[0014] In the above scheme, the top and bottom of the separating fabric are respectively connected to the upper layer and the bottom layer by needle punching with fiber filaments, and the fiber filaments should pass through the upper layer and the bottom layer respectively.

[0015] In the above scheme, the cross-section of the small grid is hexagonal or square.

[0016] In the above scheme, the horizontal side length of the small grid is ≤200mm, preferably 20-50mm.

[0017] In the above scheme, the hot repair material includes the following raw materials in the following mass fractions: 20-30% bauxite with a particle size of 1-3mm, 25-35% bauxite with a particle size of 0.1-1mm, 20-30% fine bauxite powder, 10-20% fine clay powder, 2-5% brucite powder, and 5-10% binder.

[0018] Furthermore, the particle size of the bauxite powder, clay powder, and brucite powder is all <100μm.

[0019] Furthermore, the binder is one or more of thermosetting resin powder, boric acid, boric anhydride, and hydrated sodium metasilicate.

[0020] Furthermore, the clay powder and brucite powder are premixed before being mixed with other raw materials of the hot-state repair material.

[0021] In the above scheme, the hot-state repair material composite ceramic fiber blanket is in the form of a blanket roll or folded block before construction, with a single layer thickness of 10-200mm.

[0022] This invention also provides a hot-state repair construction method for a composite ceramic fiber blanket, comprising the following steps:

[0023] 1) Repair the construction surface inside the industrial kiln that needs repair, so that the construction surface forms a repair groove;

[0024] 2) Cut or continue to lay the hot-state repair material composite ceramic fiber blanket to match its shape and size with the repair groove to obtain the repair module;

[0025] 3) Apply fiber adhesive to the bottom layer of the repair module, then send it to the repair groove, ensuring that the bottom layer is laid tightly against the bottom surface of the repair groove, and press the edge into the repair groove with a hammer;

[0026] 4) The repair module is cured under the residual temperature of the industrial kiln, thus completing the repair.

[0027] In the above scheme, the hot-state repair material composite ceramic fiber blanket is cut along the dividing fabric to ensure that the cut repair module is a closed body with the dividing fabric as the side boundary.

[0028] In the above scheme, the curing temperature is ≥400℃. When the residual temperature of the industrial kiln is less than 400℃, a flame torch can be used to assist in heating and curing.

[0029] In the above scheme, the bulk density of the hot-pressed repair material composite ceramic fiber blanket after curing is 2.45-2.55 g / cm³. 3 The compressive strength after curing is 2-5 MPa; the compressive strength after firing at 1400℃ for 3 hours is 12-20 MPa.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1) This invention combines hot-state repair material with ceramic refractory fiber. Through structural design, the hot-state repair material is filled into small cells inside the ceramic fiber blanket, effectively avoiding segregation of the hot-state repair material during transportation. It also solves the problem of dust pollution caused by on-site mixing of dry repair materials. This design, using ceramic fiber blankets for construction, fully leverages the advantages of the fiber blankets' strong integrity and rapid construction. After construction, it is sintered and cured to transform into a rigid, integral furnace lining, maximizing the rapid sintering and repair performance of the hot-state repair material.

[0032] 2) The ceramic fiber cloth in the upper, lower, and vertically arranged layers of this invention is sintered and hardened together with the hot repair material, overcoming the shortcomings of ceramic fiber cloth, such as low strength, large shrinkage, and rough surface, making it difficult to use in the inner lining working layer. A clearly defined modified sintered layer is formed at the junction of the lower surface and the construction surface, which is easy to clean during later maintenance. The vertically arranged ceramic fiber cloth plays a role in strengthening and toughening, and after sintering, it provides fiber reinforcement to the furnace lining. In addition, the ceramic fiber cloth in the upper and lower layers is pre-treated with liquid organic aluminum and active magnesium oxide powder. The liquid organic aluminum decomposes into nano-sized alumina at high temperature, which reacts with active magnesium oxide to generate spinel, resulting in volume expansion, filling the pores between ceramic fibers, making the surface dense, and further increasing the toughness and strength of the product. At the same time, magnesium oxide reacts with the original surface of the furnace lining to form a penetration layer, enhancing the bonding force between the repair material and the furnace lining.

[0033] 3) This invention is mainly used for hot repair of high-temperature furnaces and kilns with aluminum-silicon refractory linings. In the design of the hot repair material, brucite powder is added and premixed with fine clay powder. When heated, brucite releases water, which wets and fuses the powder, densifies the air, and decomposes brucite to form a small amount of magnesium oxide, which reacts with fine clay powder to generate a low-melting-point cordierite phase, promoting sintering, improving the thermal stability of the repaired area, and preventing detachment due to thermal stress. In addition, the hot repair material of this invention releases water from the mixture after heating through hydrated sodium metasilicate and brucite in the binder, reducing the addition of various inorganic salt additives such as water-reducing agents, accelerators, and air-entraining agents, reducing costs, and improving the refractory performance of the material. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of the hot-state repair material composite ceramic fiber blanket of Embodiment 1 of the present invention.

[0035] Figure 2 for Figure 1 AA section diagram.

[0036] In the diagram: 1. Top layer; 2. Filling layer; 3. Bottom layer; 4. Divider fabric; 5. Small grid. Detailed Implementation

[0037] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0038] Example 1

[0039] like Figure 1 and Figure 2 As shown, a hot-state repair material composite ceramic fiber blanket comprises, from top to bottom, an upper layer 1, a filling layer 2, and a bottom layer 3. Several staggered partition fabrics 4 are arranged between the upper layer 1 and the bottom layer 3. The vertically arranged partition fabrics 4 form a mesh structure that divides the filling layer 2 into several small square grids 5 with a side length of 30mm. The grids 5 are filled with hot-state repair material. The upper layer 1, the bottom layer 3, and the partition fabrics 4 are all ceramic fiber cloths woven from aluminosilicate refractory fibers. The top and bottom of the partition fabrics 4 are respectively connected to the upper layer 1 and the bottom layer 3 by fiber needle punching, with the fiber filaments passing through the upper layer 1 and the bottom layer 3 during connection. The ceramic fiber cloths of the upper layer 1 and the bottom layer 3 are pre-impregnated with aluminum isopropoxide melt at a temperature of 125℃, and before solidification, active magnesium oxide powder with a particle size <200 mesh is sprayed. The thickness of the upper layer 1 and the bottom layer 3 is 0.5mm, the thickness of the partition fabric is 0.25mm, and the final thickness of the hot-state repair material composite ceramic fiber blanket is 150mm.

[0040] The hot-state repair material used in this embodiment includes the following raw materials by mass fraction: 30% bauxite with a particle size of 1-3mm, 25% bauxite with a particle size of 0.1-1mm, 22% bauxite fine powder with a particle size of <100μm, 10% clay fine powder with a particle size of <100μm, 5% brucite powder with a particle size of <100μm, and 8% sodium metasilicate nonahydrate. The preparation method is as follows: first, the clay fine powder and brucite powder are premixed evenly, and then the other raw materials are added and mixed evenly to obtain the hot-state repair material.

[0041] The hot-state repair material composite ceramic fiber blanket of this embodiment is used for hot-state repair of an industrial kiln. The hot-state repair construction method includes the following steps:

[0042] 1) Use a cutting machine and a pneumatic pick to trim the construction surface inside the industrial kiln that needs repair, so that the construction surface forms a repair groove, and use an oxygen gun to blow away the dust and residue.

[0043] 2) Cut or continue to lay the hot-state repair material composite ceramic fiber blanket to match its shape and size with the repair groove to obtain the repair module; cut along the dividing cloth to ensure that the cut repair module is a closed body with the dividing cloth as the side boundary;

[0044] 3) Apply fiber adhesive to the bottom layer of the repair module, use a robot to deliver it to the repair groove, so that the bottom layer is laid tightly against the bottom surface of the repair groove, and press the edge hammer into the repair groove;

[0045] 4) Utilizing the residual heat of the industrial kiln, the brucite and sodium metasilicate nonahydrate in the repair module decompose and release water, which wets the repair material powder, removes gas between the powder particles, and densifies the repair material. As the temperature rises, the sodium silicate generated from the decomposition of sodium metasilicate nonahydrate in the repair module forms a liquid phase that further coats the repair material powder, promoting sintering. The magnesium oxide generated from the decomposition of brucite reacts with fine clay powder to form a cordierite phase, improving the material's thermal shock resistance. The alumina generated from the decomposition of aluminum isopropoxide in the upper and lower layers reacts with activated magnesia to form a spinel phase, filling the fiber pores in the upper and lower layers, making the surface structure dense. At the same time, the spinel synthesis reaction in the lower layer erodes and penetrates into the construction surface, increasing the bonding strength and improving the repair material's anti-stripping performance. Under the combined effect of the above, the repair module solidifies, thus completing the repair.

[0046] Testing revealed that the bulk density of the hot-pressed repair material composite ceramic fiber blanket after curing was 2.52 g / cm³. 3 The compressive strength after curing is 4.8 MPa, and the compressive strength after firing at 1400℃ for 3 hours is 19.2 MPa, which meets the service requirements of industrial kiln linings.

[0047] Example 2

[0048] A hot-state repair material composite ceramic fiber blanket comprises, from top to bottom, an upper layer 1, a filling layer 2, and a bottom layer 3. Several staggered partition fabrics 4 are arranged between the upper layer 1 and the bottom layer 3. The vertically arranged partition fabrics 4 form a mesh structure that divides the filling layer 2 into several regular hexagonal grids 5 with a side length of 40 mm. The grids 5 are filled with hot-state repair material. The upper layer 1, the bottom layer 3, and the partition fabrics 4 are all ceramic fiber cloths woven from zirconium-alumina silicate refractory fibers. The top and bottom of the partition fabrics 4 are respectively connected to the upper layer 1 and the bottom layer 3 by fiber needle punching, with the fiber filaments passing through the upper layer 1 and the bottom layer 3 during connection. The ceramic fiber cloths of the upper layer 1 and the bottom layer 3 are pre-sprayed with a saturated aluminum acetate solution at room temperature and sprayed with active magnesium oxide powder with a particle size <200 mesh before solidification. The thickness of the upper layer 1 and the bottom layer 3 is 0.8 mm, the thickness of the partition fabric is 0.4 mm, and the final thickness of the hot-state repair material composite ceramic fiber blanket is 180 mm.

[0049] The hot-state repair material used in this embodiment includes the following raw materials by mass fraction: 28% alumina with a particle size of 1-3mm, 30% alumina with a particle size of 0.1-1mm, 20% alumina fine powder with a particle size of <100μm, 10% clay fine powder with a particle size of <100μm, 2% brucite powder with a particle size of <100μm, 8% epoxy resin powder, and 2% boron anhydride. The preparation method is as follows: first, the clay fine powder and brucite powder are premixed evenly, and then the other raw materials are added and mixed evenly to obtain the hot-state repair material.

[0050] The hot-state repair material composite ceramic fiber blanket of this embodiment is used for hot-state repair of an industrial kiln. The hot-state repair construction method includes the following steps:

[0051] 1) Use a cutting machine and a pneumatic pick to trim the construction surface inside the industrial kiln that needs repair, so that the construction surface forms a repair groove, and use an oxygen gun to blow away the dust and residue.

[0052] 2) Cut or continue to lay the hot-state repair material composite ceramic fiber blanket to match its shape and size with the repair groove to obtain the repair module; cut along the dividing cloth to ensure that the cut repair module is a closed body with the dividing cloth as the side boundary;

[0053] 3) Apply fiber adhesive to the bottom layer of the repair module, use a robot to deliver it to the repair groove, so that the bottom layer is laid tightly against the bottom surface of the repair groove, and press the edge hammer into the repair groove;

[0054] 4) Utilizing the residual heat of the industrial kiln, the resin in the repair module is liquefied, impregnating the powder, expelling gas, and densifying the material; as the temperature rises, the boron anhydride in the repair module liquefies, forming a boron-rich liquid phase, which promotes the sintering of various reactants in the repair material, the reaction and sintering of brucite and clay, the reaction and sintering of aluminum acetate and active magnesium powder, the coking of the resin, and the densification of the fiber layer; under the combined effect of the above, the repair module solidifies, thereby completing the repair.

[0055] Testing revealed that the bulk density of the hot-pressed repair compound ceramic fiber blanket after curing was 2.48 g / cm³. 3 The compressive strength after curing is 3.5 MPa, and the compressive strength after firing at 1400℃ for 3 hours is 17.6 MPa, which meets the service requirements of industrial kiln linings.

[0056] Example 3

[0057] A hot-state repair material composite ceramic fiber blanket comprises, from top to bottom, an upper layer 1, a filling layer 2, and a bottom layer 3. Several staggered partition fabrics 4 are arranged between the upper layer 1 and the bottom layer 3. The vertically arranged partition fabrics 4 form a mesh structure that divides the filling layer 2 into several small square grids 5 with a side length of 40mm. The grids 5 are filled with hot-state repair material. The upper layer 1 and the bottom layer 3 are ceramic fiber cloths woven from aluminosilicate, and the partition fabrics 4 are ceramic fiber cloths woven from zirconium-containing aluminosilicate refractory fibers. The top and bottom of the partition fabrics 4 are respectively needle-punched to the upper layer 1 and the bottom layer 3 using zirconium-containing fiber filaments. During connection, the zirconium-containing fiber filaments pass through the upper layer 1 and the bottom layer 3 respectively. The ceramic fiber cloths of the upper layer 1 and the bottom layer 3 are pre-sprayed with a saturated aluminum formate solution at room temperature and sprayed with active magnesium oxide powder with a particle size <200 mesh before solidification. The thickness of the upper layer 1 and the bottom layer 3 is 1mm, the thickness of the partition fabric is 0.2mm, and the final thickness of the hot-state repair material composite ceramic fiber blanket is 100mm.

[0058] The hot-state repair material used in this embodiment includes the following raw materials by mass fraction: 30% 70% alumina with a particle size of 1-3mm, 25% alumina with a particle size of 0.1-1mm, 22% alumina fine powder with a particle size of <100μm, 10% clay fine powder with a particle size of <100μm, 3% brucite powder with a particle size of <100μm, 8% sodium metasilicate pentahydrate, and 2% boric acid. The preparation method is as follows: first, the clay fine powder and brucite powder are premixed evenly, and then the other raw materials are added and mixed evenly to obtain the hot-state repair material.

[0059] The hot-state repair material composite ceramic fiber blanket of this embodiment is used for hot-state repair of tunnel kilns. The hot-state repair construction method includes the following steps:

[0060] 1) Use a cutting machine and a pneumatic pick to trim the construction surface of the tunnel kiln lining that needs repair, so that the construction surface forms a square repair groove, and use an oxygen gun to blow away the dust and residue.

[0061] 2) Cut the hot-state repair material composite ceramic fiber blanket to match its shape and size with the repair groove to obtain the repair module; cut along the dividing cloth to ensure that the cut repair module is a closed body with the dividing cloth as the side boundary;

[0062] 3) Apply fiber adhesive to the bottom layer of the repair module, use a robot to deliver it to the repair groove, so that the bottom layer is laid tightly against the bottom surface of the repair groove, and press the edge hammer into the repair groove;

[0063] 4) Utilizing the residual heat inside the tunnel kiln, sodium metasilicate pentahydrate and brucite in the repair module release water, which wets the powder, removes gas, and densifies the material. As the temperature rises, boric acid in the repair module decomposes and liquefies to produce a boron-rich liquid phase, thereby enhancing the sintering reaction of the repair material and inducing other components in the system to interact more easily, thus improving sintering. At the same time, aluminum formate in the repair module decomposes into alumina powder. As the temperature further rises, the alumina powder reacts with active magnesium oxide powder to generate spinel, which fills the fiber gaps in the upper and lower layers, forming a dense surface layer. Under the combined effect of the above, the repair module solidifies, thus completing the repair.

[0064] Testing revealed that the bulk density of the hot-pressed repair compound ceramic fiber blanket after curing was 2.55 g / cm³. 3 The compressive strength after curing is 4.0 MPa, and the compressive strength after firing at 1400℃ for 3 hours is 15 MPa, which meets the service requirements of industrial kiln linings.

[0065] The above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations, and any obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A hot-state repair material composite ceramic fiber blanket, characterized in that, The structure consists of an upper layer (1), a filling layer (2), and a bottom layer (3) from top to bottom. Several staggered partition cloths (4) are provided between the upper layer (1) and the bottom layer (3). The partition cloths (4) are vertically arranged to form a mesh structure that divides the filling layer (2) into several small grids (5). The small grids (5) are filled with hot repair material. The upper layer (1), the bottom layer (3), and the partition cloths (4) are all ceramic fiber cloths. The ceramic fiber cloths of the upper layer (1) and the bottom layer (3) are pre-impregnated or sprayed with liquid organic aluminum, and active magnesium oxide powder is sprayed before the liquid organic aluminum solidifies.

2. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The thickness of the upper layer (1) and the bottom layer (3) is ≤5mm, the thickness of the separating cloth (4) is ≤1mm, and the thickness of the hot-state repair material composite ceramic fiber blanket is 10-200mm.

3. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The ceramic fiber cloth is woven from one or more of aluminosilicate refractory fibers and zirconium-containing aluminosilicate refractory fibers.

4. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The liquid organoaluminum is an aluminum isopropoxide melt at a temperature of 120-135℃, or a saturated solution of aluminum formate or aluminum acetate at room temperature; the particle size of the active magnesium oxide powder is <200 mesh.

5. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The top and bottom of the separating fabric (4) are respectively connected to the upper layer (1) and the bottom layer (3) by needle punching with fiber filaments, and the fiber filaments should pass through the upper layer (1) and the bottom layer (3) respectively.

6. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The cross-section of the small grid (5) is hexagonal or square, with a lateral side length ≤200mm.

7. The hot-state repair material composite ceramic fiber blanket according to claim 1, characterized in that, The hot-state repair material comprises the following raw materials in the following mass fractions: 20-30% bauxite with a particle size of 1-3 mm, 25-35% bauxite with a particle size of 0.1-1 mm, 20-30% fine bauxite powder with a particle size of <100 μm, 10-20% fine clay powder, 2-5% brucite powder, and 5-10% binder.

8. The hot-state repair material composite ceramic fiber blanket according to claim 7, characterized in that, The binder is one or more of the following: thermosetting resin powder, boric acid, boric anhydride, and hydrated sodium metasilicate.

9. The hot-repair construction method of the hot-repair material composite ceramic fiber blanket according to any one of claims 1-8, characterized in that, Includes the following steps: 1) Repair the construction surface inside the industrial kiln that needs repair, so that the construction surface forms a repair groove; 2) Cut or continue to lay the hot-state repair material composite ceramic fiber blanket to match its shape and size with the repair groove to obtain the repair module; 3) Apply fiber adhesive to the bottom layer of the repair module, then send it to the repair groove, ensuring that the bottom layer is laid tightly against the bottom surface of the repair groove, and press the edge into the repair groove with a hammer; 4) The repair module is cured under the residual temperature of the industrial kiln, thus completing the repair.

10. The hot-state repair construction method for the composite ceramic fiber blanket according to claim 9, characterized in that, The bulk density of the hot-pressed repair material composite ceramic fiber blanket after curing is 2.45-2.55 g / cm³. 3 The compressive strength after curing is 2-5 MPa, and the compressive strength after firing at 1400℃ for 3 hours is 12-20 MPa.

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