Thermostable composite material and furnace wall using thermostable composite material

Abstract

To provide a thermostable composite material, effectively using standard refractory and an integrated body of alumina-highly containing fibers, the integrated body being light, easy to handle, superior in workability, superior in durability, and low in heat capacity, where the thermostable composite material: retains superior dimension stability even being used at a high temperature of 1600°C or higher; can be effectively used as a lining material of a furnace wall; is easy to handle when installed to the furnace wall compared with the standard refractory; and can prevent debris from dropping off, which would be otherwise caused by cracking.SOLUTION: A thermostable composite material (composite body) is formed by integrating an integrated body of alumina-highly containing fibers containing alumina 70% or more on a mass ratio basis and hexahedron standard refractory and is used as a lining furnace material fire-resistant and thermostable. The thermostable composite material is integrated in a state in which one side face and two flat faces of the standard refractory are covered by the integrated body and other three side faces are exposed, where an end face of the integrated body and an end face of the refractory are faced to match on a same plane, in the three side faces other than the one side face covered by the integrated body of the standard refractory, and forms the same plane. Also, a furnace wall using the thermostable composite material is provided.SELECTED DRAWING: Figure 1A

Description

Technical Field

[0001] The present invention relates to a heat-resistant composite material useful as a lining furnace material used in, for example, industrial heating furnaces, etc., and a furnace wall formed using the heat-resistant composite material. The present invention relates to a technique for effectively utilizing an aggregate of high-alumina-containing fibers. In the present invention, hereinafter, a "ceramic blanket" will be cited as a representative example of the aggregate of ceramic fibers for explanation.

Background Art

[0002] Conventionally, in industrial furnaces such as heating furnaces and heat treatment furnaces, heat-resistant materials called refractories have been used as refractory and heat-insulating lining furnace materials. On the other hand, in recent years, as an alternative to conventional refractories, heat-resistant blocks formed using blankets made of aggregates of ceramic fibers having excellent various functionalities such as light weight, low heat storage property, and heat insulation property have been developed and are being widely used.

[0003] Regarding heat-resistant blocks made of ceramic blankets, various proposals have been made, for example, as listed below. In Patent Document 1, a heat-resistant block is proposed in which a laminate of a ceramic blanket and a heat-resistant cloth is stitched and integrated with a string-like body made of long-fiber alumina fibers. Further, in Patent Document 2, an inner layer body made of a crystalline alumina fiber mat having a bulk density of 60 to 80 kg / m 3 and an outer layer body made of a crystalline alumina fiber blanket having a bulk density of 100 to 130 kg / m 3 and a three-layer laminate composed of a gauze attached to the outside of the outer layer body are continuously folded in a corrugated shape (accordion shape) to form a ceramic fiber block.

[0004] In addition, Patent Document 3 proposes a three-layer laminated ceramic fiber block in which an outer layer body is a crystalline alumina fiber blanket, an inner layer body is a crystalline alumina fiber mat in which alumina fibers are three-dimensionally randomly oriented and intertwined with each other, the outer layer body covers the outer surface of the inner layer body in a state of being sandwiched between the folded portions of the inner layer body, and a cloth is attached to the outside of the outer layer body. The bulk density of the crystalline alumina fiber mat is 50 to 80 kg / m 3 and the bulk density of the crystalline alumina fiber blanket is 100 to 130 kg / m 3 There has been proposed a ceramic fiber block continuously folded in a pleated (accordion-like) shape, which is composed of an inner layer body, an outer layer body, and a cloth attached to the outside of the outer layer body.

[0005] In addition, Patent Document 4 proposes a heat-resistant block that can be manufactured at low cost while maintaining heat resistance by laminating two types of ceramic blankets having different maximum use temperatures of 50°C or higher. Further, Patent Document 5 proposes a heat insulating material containing 40 to 60% by mass of a high heat-resistant ceramic fiber of 1400°C or higher and 40 to 60% by mass of an inorganic filler composed of metal oxide particles having an average particle diameter of 100 nm or less, and having a pore volume of 30% or more and 60% or less.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0007] Incidentally, it is known that the ceramic blanket constituting the heat-resistant block and heat insulating material as described above undergoes dimensional shrinkage due to sintering of ceramic fibers when heated at high temperatures. Therefore, the heat-resistant block and the heat insulating material itself using the ceramic blanket also shrink in dimensions when repeatedly used at a temperature of 1600°C or higher. This means that when using a heat-resistant block or heat insulating material made of a ceramic blanket as an inner lining material for a heating furnace or the like that needs to be used at a high temperature of 1600°C or higher, gaps are generated between the blocks, and problems such as fire leakage occur from the gaps. Therefore, heat-resistant blocks and heat insulating materials made of ceramic blankets cannot be applied as lining materials for furnaces for use at the above-mentioned high temperatures.

[0008] On the other hand, for inner lining materials of heating furnaces and the like used at 1600°C or higher, it is common to use so-called refractory bricks and refractory heat insulating bricks, etc., which have little dimensional change even at high temperatures. However, generally, refractory materials have a larger heat capacity and a higher thermal conductivity compared to the heat-resistant blocks made of the ceramic fiber-based materials described above. Therefore, when used as an inner lining material for a heating furnace, there is a problem that the energy-saving effect is low. In recent years, when the effective utilization of limited resources has become an important social issue, the improvement of energy efficiency has become an urgent issue to be addressed. In addition, compared with heat-resistant blocks, general refractory heat insulating bricks have a high bulk density, a complicated construction method, and furthermore, according to the studies of the present inventors, cracks occur due to repeated heating and cooling during the operation of the heating furnace, and in some cases, there are practical problems such as fragments falling off from the surface. Also, refractory heat insulating bricks have a higher specific heat compared to heat-resistant blocks, that is, the energy required to heat them themselves is higher, which leads to a reduction in the heating efficiency of the heating furnace itself. If these problems can be easily improved, it will be extremely useful industrially.

[0009] Accordingly, an object of the present invention is to provide a heat-resistant composite material having excellent properties not found in the prior art by compounding a general refractory used as an inner furnace lining material such as a heating furnace with another material. The ultimate object of the present invention is to effectively utilize a high-alumina-containing fiber aggregate (ceramic blanket) used in a heat-resistant block, which is lighter in weight, superior in workability, excellent in durability, and has a low heat capacity compared to the above-described general refractory, so that even when used at a high temperature of 1600°C or higher, it can be effectively used as a refractory and heat-insulating inner furnace lining material (inner lining material of the furnace wall) that ensures excellent dimensional stability, and the construction of the furnace wall is simpler compared to general refractory heat-insulating bricks, and it is also possible to suppress cracks and the detachment of fragments from the surface. The present invention aims to develop a useful technology that can provide a heat-resistant composite material.

Means for Solving the Problems

[0010] The inventors of the present invention have conducted intensive studies to solve the above problems. As a result, by using a ceramic blanket used in a heat-resistant block and a shaped refractory that exhibits a high residual linear expansion rate (i.e., thermal expansion) during the firing process from room temperature to a heating state of 1600°C or higher and then back to room temperature in a specific form to form a heat-resistant composite material, it is possible to provide a heat-resistant composite material that can be used even in a heating furnace at 1600°C or higher where a heat-resistant block cannot be used due to dimensional changes caused by volume shrinkage, and the inventors have found that the above various problems can be solved and thus completed the present invention.

[0011] That is, the present invention provides the following heat-resistant composite material. [1] A heat-resistant composite material used as a refractory and heat-insulating inner furnace lining material, which is a composite body in which an aggregate of high-alumina-containing fibers containing 70% or more of alumina by mass, which is a heat-resistant material, and a hexahedral shaped refractory used as an inner furnace lining material of a heating furnace are compounded and integrated. One side and two planes of the hexahedral shaped refractory are covered by the laminate, and the other three sides are exposed and combined, and on the three sides other than the one side covered by the laminate, the end face of the laminate and the end face of the refractory are butted in a flush state to form the same plane, and the heat-resistant composite material is characterized by this.

[0012] The following are preferable forms of the heat-resistant composite material of the present invention. [2] Further, it is a block-shaped heat-resistant composite material having a laminated structure in which a plurality of the composites are laminated, and the laminated structure is laminated in a direction in which the laminates covering the plane overlap, and in the lamination direction, a layer made of the laminate and a layer made of the shaped refractory are continuously formed, and on the three sides other than the one side of the shaped refractory covered by the laminate, the end face of the laminate and the end face of the refractory are butted in a flush state to form the same plane, and the heat-resistant composite material according to [1] above, wherein the length in the lamination direction is 150 mm or more. [3] The heat-resistant composite material according to [1] or [2] above, wherein the use temperature of the laminate is 1600°C or higher and the use temperature of the shaped refractory is 1600°C or higher. [4] The laminate is a blanket made of the following high alumina-containing fibers, and the bulk density of the shaped refractory is 2000 kg / m 3 The following heat-resistant composite material according to any one of [1] to [3] above. 3 The heat-resistant composite material according to any one of [1] to [3] above, wherein the bulk density of the shaped refractory is 2000 kg / m or less. [5] The heat-resistant composite material according to any one of [1] to [4] above, wherein the shaped refractory is a material that expands upon heating and exhibits a high residual linear expansion rate (i.e., expands thermally) during the firing process from room temperature to a heated state of 1600°C or higher and back to room temperature. [6] The heat-resistant composite material according to any one of [1] to [5] above, wherein the material composition of the composite is 30 to 70% by volume of the high alumina-containing fibers and 30% to 70% of the shaped refractory. [7] The heat-resistant composite material according to any one of [1] to [6] above, wherein the shape of the composite is 50 to 350 mm in length, 50 to 350 mm in width, and 50 to 300 mm in thickness. [8] Further, a dropout prevention pin is provided to prevent the shaped refractory from dropping out of a block-shaped heat-resistant composite material having a laminated structure in which a plurality of the composites are laminated. The dropout prevention pin is arranged in a state of penetrating both the aggregate constituting the plurality of laminated composites and the shaped refractory. The heat-resistant composite material according to any one of [2] to [7] above.

[0013] Another embodiment of the present invention is as follows. [9] A furnace wall made of a refractory and heat-insulating inner furnace lining material, wherein a plurality of the heat-resistant composite materials according to any one of [1] to [8] above are used as the refractory and heat-insulating inner furnace lining material, and the aggregate is arranged inside the furnace. A furnace wall characterized by being configured as such.

[0014] Preferred forms of the furnace wall of the present invention are as follows.

[10] In the above [9], the plurality of heat-resistant composite materials are arranged such that the shaped refractory materials constituting the laminate are arranged in a straight line in the vertical direction, or the positions of the shaped refractory materials constituting the laminate in adjacent heat-resistant composite materials are arranged alternately in the vertical and horizontal directions. Furnace wall.

Advantages of the Invention

[0015] According to the present invention, when used at a high temperature of 1600 °C or higher, by compounding a general refractory used as an inner lining material of a heating furnace or the like with another material, it becomes possible to provide a heat-resistant composite material having unprecedented characteristics. More specifically, according to the present invention, the above-described general refractory and a ceramic blanket used for a heat-resistant block, which is lighter, has excellent workability, is excellent in durability, and has a low heat capacity compared to the general refractory, are compounded in a good state, solving the problem that the energy-saving effect in a general refractory is low. Also, compared to general refractory heat-insulating bricks, the construction of the furnace wall is simple, and it becomes possible to provide an excellent industrially useful heat-resistant composite material that can effectively suppress the occurrence of cracks in the refractory heat-insulating bricks and the falling off of fragments from the surface. Further, according to a preferred form of the present invention, in addition to the above-described effects, even when using a ceramic blanket that shrinks in dimensions when repeatedly used at a temperature of 1600 °C or higher, excellent dimensional stability can be ensured even when used at a temperature above the above temperature, making it possible to provide an excellent heat-resistant composite material that can be effectively used for the inner lining material (inner lining of the furnace wall) for fire resistance and heat insulation on the furnace wall. According to a preferred form of the present invention, by skillfully compounding the ceramic blanket used for the above-described heat-resistant block and a shaped refractory that exhibits a high residual linear expansion rate (i.e., expands thermally) during the firing process from room temperature to a heating state of 1600 °C or higher and back to room temperature to form a heat-resistant material, it becomes possible to provide a heat-resistant composite material that can be used even in a heating furnace at 1600 °C or higher where heat-resistant blocks cannot be used.

Brief Description of the Drawings

[0016]

Figure 1A

Figure 1B

Figure 2

Figure 3A

Figure 3B

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0017] Hereinafter, the present invention will be described in detail with reference to preferred embodiments. However, the present invention is not limited to the following embodiments, and includes all objects having the specific matters of the invention. The heat-resistant composite material of the present invention is a composite body in which an aggregate of high-alumina-containing fibers containing 70% or more of alumina by volume ratio, which is a heat-resistant material, and a hexahedral shaped refractory used as an inner lining material of a heating furnace are combined and integrated, and is a heat-resistant composite material used as an inner lining material for fire resistance and heat insulation. In the heat-resistant composite material, one side surface and two plane surfaces of the hexahedral shaped refractory are covered with the aggregate, and the other three side surfaces are exposed and combined, and on the three side surfaces other than one side surface of the shaped refractory covered with the aggregate, the aggregate and the refractory are butted in a flush state to form the same plane.

[0018] As described above, the heat-resistant composite material of the present invention is formed by combining and integrating a ceramic blanket made of a specific material defined in the present invention and a hexahedral shaped refractory (also simply referred to as a shaped refractory) generally used as an inner lining material of a heating furnace. The heat-resistant composite material of the present invention is, for example, a composite material formed by combining a ceramic blanket 1 and a shaped refractory 2 as illustrated in FIGS. 1A and 1B, and examples include a block-shaped laminated structure formed by laminating a plurality of heat-resistant composite materials having the configuration illustrated in FIG. 1A as illustrated in FIG. 2. Details of these will be described later. First, the ceramic blanket and the shaped refractory constituting the heat-resistant composite material of the present invention will be described.

[0019] <Aggregate of high-alumina-containing fibers (taking a ceramic blanket as a representative example)> In the present invention, from the perspective of the heat resistance of the heat-resistant composite material formed by compounding, an aggregate of high-alumina-containing fibers (fibers) containing 70% or more of alumina, which is a heat-resistant material, by mass ratio is used. With the above configuration, it is possible to obtain a ceramic blanket with high heat resistance that can withstand use in a portion exposed to a furnace with a maximum use temperature of 1600 °C or higher. The upper limit of the maximum use temperature is not particularly limited, but considering the manufacturing cost, it is preferable to use a ceramic blanket with a maximum use temperature of 1800 °C or lower, and more preferably 1700 °C or lower.

[0020] As described above, the ceramic blanket constituting the present invention is an aggregate of high-alumina-containing fibers. In the present invention, the "high-alumina-containing fibers" means alumina-based ceramic fibers having an alumina content of 70% or more by mass ratio. The upper limit of the alumina content is not particularly limited, and those with an alumina content of 100% by mass can also be used. According to the study by the present inventors, considering the balance between the manufacturing cost and the heat resistance of the obtained heat-resistant composite material, it is preferably 80% by mass or less.

[0021] The components other than alumina in the alumina-based ceramic fibers of the ceramic blanket constituting the present invention are not particularly limited. For example, silica and the like can be mentioned and can be preferably used. That is, the high-alumina-containing fibers constituting the present invention are preferably alumina-silica-based. Further, when the high-alumina-containing fibers used in the present invention are of high heat resistance and are alumina-silica-based, the total content of alumina and silica is preferably 98% by mass or more on a weight basis. More preferably, it is 99% by mass or more.

[0022] Furthermore, the heat-resistant composite material of the present invention can be suitably used for a furnace wall made of a refractory and heat-insulating inner lining material, and it is preferable that the furnace material has a low heat capacity. On the other hand, the ceramic blanket constituting the present invention has a small bulk density, that is, the lower the bulk density, the lower the heat capacity, and the higher the heating efficiency of the heating furnace when used as a furnace material. Therefore, considering the reduction of the energy required for heating the furnace material, the ceramic blanket constituting the present invention preferably consists of high-alumina-containing fibers with a bulk density of 200 kg / m 3 or less.

[0023] The high heat-resistant high-alumina-containing fiber itself that forms the ceramic blanket constituting the present invention is a high melting point material, but due to its manufacturing method, it becomes an amorphous fiber without crystallinity. When the amorphous fiber is heated at a high temperature of 1000 °C or higher, it changes into a crystalline fiber while accompanying volume shrinkage. This volume shrinkage is the volume shrinkage of the aggregate of the high heat-resistant high-alumina-containing fibers itself. Therefore, when such a material is used as a furnace material for a heating furnace, gaps are generated between the furnace materials, which causes fire leakage (see "Iron and Steel", No. 16, 69th year (1983), pp. 19-24). The volume shrinkage that occurs when the high-alumina-containing fiber is heated starts at about 1000 °C and becomes more significant when the temperature reaches 1600 °C or higher, depending on the material of the fiber. For this reason, the heat-resistant block or heat-insulating material itself made of the ceramic blanket also shrinks in dimensions when repeatedly used at a temperature of 1600 °C or higher. The heat-resistant composite material of the present invention improves the problem of dimensional shrinkage of the ceramic blanket by skillfully compounding the ceramic blanket and a general shaped refractory, enabling the practical application of a useful heat-resistant composite material that can be used even at a use temperature of 1600 °C or higher.

[0024] The shape of the ceramic blanket constituting the present invention is not particularly limited. It may be appropriately determined in consideration of the shape of the shaped refractory used when compounding with the ceramic blanket to form the heat-resistant composite material of the present invention. The heat-resistant composite material of the present invention is formed by compounding in a state where one side surface and two plane surfaces of a hexahedral shaped refractory are covered with a ceramic blanket and the other three side surfaces are exposed, and on the three exposed side surfaces of the shaped refractory other than the one side surface covered with the ceramic blanket, the ceramic blanket and the hexahedral shaped refractory are butted in a flush state to form the same plane. When the heat-resistant composite material of the present invention formed by compounding two kinds of materials as described above is applied to a furnace lining material, the shape of the furnace lining material is, for example, a block shape having dimensions of 50 to 350 mm in length, 50 to 350 mm in width, and 50 to 300 mm in thickness. Therefore, the shape of the heat-resistant composite material of the present invention may be appropriately designed within the above range in consideration of this point. In that case, as the form of the single body of the heat-resistant composite material of the present invention, those exemplified in FIGS. 1A and 1B may be mentioned, and it may be designed in consideration of this point. Further, when the heat-resistant composite material of the present invention is applied to a furnace lining material, as shown in FIG. 2, for example, a laminated structure having a block shape formed by laminating a plurality of single bodies having the shape shown in FIG. 1 is preferable. Therefore, the form of the single body of the heat-resistant composite material of the present invention may be determined in consideration of this point.

[0025] <shaped refractory> The shaped refractory constituting the present invention is a general hexahedral shaped refractory (refractory brick) used as the inner lining material of a heating furnace. Similar to the ceramic blanket described above, the shaped refractory constituting the present invention preferably has a use temperature of 1600 ° C or higher from the viewpoint of heat resistance. Further, in view of reducing the heat capacity of the furnace lining material in view of applying the shaped refractory constituting the present invention to the furnace lining material, the bulk density of the shaped refractory constituting the present invention is 2000 kg / m 3 It is preferably the following. Furthermore, the bulk density is 1500 kg / m 3 It is more preferably the following.

[0026] Further, according to the studies of the present inventors, in the heat-resistant composite material of the present invention having a configuration in which a shaped refractory constituting the present invention is combined with a ceramic blanket, the effect of the present invention obtained is more effective when the shaped refractory shows a residual linear expansion rate of 3% or more during the cooling process from a heating state of 1600 °C or higher to room temperature. That is, by applying the shaped refractory showing the above residual linear expansion rate, when the heat-resistant composite material of the present invention is used as a furnace lining material for a heating furnace used at a temperature of 1600 °C or higher, the volume shrinkage occurring in the ceramic blanket constituting the present invention can be effectively compensated by the expansion of the shaped refractory constituting the present invention and combined with the ceramic blanket. As described above, when a heat-resistant block or heat insulating material using the ceramic blanket constituting the present invention is used as an inner lining furnace material for a heating furnace or the like that needs to be used at a high temperature of 1600 °C or higher, gaps may occur between the heat-resistant blocks, and problems such as fire leakage may occur from the gaps. According to the studies of the present inventors, by combining the ceramic blanket constituting the present invention and the shaped refractory having the above-described characteristics in the state defined in the present invention, the generation of gaps occurring between the blocks caused by the volume shrinkage of the ceramic blanket can be effectively suppressed. Therefore, particularly when the heat-resistant composite material of the present invention is used as a furnace lining material for a heating furnace used at a temperature of 1600 °C or higher, it is useful to use a shaped refractory having a characteristic of a high residual linear expansion rate (i.e., thermal expansion) during the firing process from room temperature to a heating state of 1600 °C or higher and then back to room temperature. Regarding the material of the shaped refractory used in this case, any oxide raw material that can achieve a heat-resistant temperature of 1600 °C or higher may be used, and it is not particularly limited.

[0027] Here, refractory materials are the general term for non-metallic inorganic substances or their products that can withstand high temperatures and are chemically stable. Oxide-based materials are often used in terms of material. The shaped refractory used in the present invention is a kind of refractory material and can be produced by a general refractory manufacturing method, and its method is not particularly limited. Considering the manufacturing cost and mass productivity, the shaped refractory constituting the heat-resistant composite material of the present invention is preferably produced by press molding using a friction press or the like.

[0028] As described above, when the heat-resistant composite material of the present invention is used as the furnace lining material of a heating furnace used at a temperature of 1600 °C or higher, it is necessary to compensate for the volume shrinkage of the ceramic blanket to be compounded with the expansion of the shaped refractory. Therefore, in this case, it is desirable to use a shaped refractory having a residual linear expansion rate of 3% or more in the firing process from room temperature to a heating state of 1600 °C or higher and then back to room temperature. Examples of methods for imparting a residual linear expansion rate of 3% or more to the shaped refractory in the cooling process from a heating state of 1600 °C or higher to room temperature include the following methods. Specifically, for example, a method of using a material having a high residual linear expansion rate such as magnesium oxide as a raw material of the shaped refractory, or the expansion when alumina (Al 2 O 3 ) and silica (SiO 2 ) react at high temperature to form mullite (3Al 2 O 3 ·2SiO 2 ) is utilized, etc., but it is not particularly limited.

[0029] FIG. 3A shows a schematic cross-sectional view for explaining the shape changes of the heat-resistant composite material 3 of the present invention having a structure in which a plurality of the heat-resistant composite materials of FIG. 1 illustrated in FIG. 2 are laminated, before heating, during heating (1600° C.), and after heating (room temperature). As shown in FIG. 3A, before heating (room temperature), the ceramic blanket does not shrink in the thickness direction and no dimensional change occurs. On the other hand, as shown in FIG. 3A, the ceramic blanket shrinks in the thickness direction during heating (1600° C. or higher) and after cooling (room temperature) as compared with before heating. In a preferred form of the heat-resistant composite material 3 of the present invention, in order to compensate for the dimensional change due to the volume shrinkage of the ceramic blanket 1 caused by heat, the shaped refractory 2 expands at a high temperature of 1600° C. or higher, and the expansion remains until after cooling, so that no apparent dimensional change occurs in the block-shaped furnace lining material.

[0030] <composite> In the attached drawings, the heat-resistant composite material (composite) of the present invention illustrated as FIGS. 1A and 1B is a composite and integrated body of an aggregate (ceramic blanket) 1 of high-alumina-containing fibers containing 70% by mass or more of alumina and a hexahedral shaped refractory 2 used as an inner lining material of a heating furnace. As shown in FIGS. 1A and 1B, in the heat-resistant composite material of the present invention, one side surface and two plane surfaces of the hexahedral shaped refractory are covered with the ceramic blanket 1, and the other three side surfaces of the ceramic blanket 1 are exposed and are composite, and on the three side surfaces other than the one side surface covered with the ceramic blanket 1, the ceramic blanket 1 and the hexahedral shaped refractory 2 are abutted in a flush state to form the same plane. As the material composition of the heat-resistant composite material (composite) of the present invention, it is preferable that the high-alumina-containing fiber is 30% to 70% and the shaped refractory is 30% to 70% in terms of volume ratio (volume %). According to the study by the present inventors, it is more preferable that the ceramic blanket (high-alumina-containing fiber) is 60% to 40% and the shaped refractory is 40% to 60% in terms of volume ratio. Further, it is more preferable that the ceramic blanket is 60% to 50% and the shaped refractory is 40% to 50%. This will be described later.

[0031] <Laminate>: Furthermore, as shown in FIG. 3, the heat-resistant composite material of the present invention can be made into a block-shaped heat-resistant composite material, for example, by laminating a plurality of composites such as those exemplified in FIG. 1A. Specifically, in the lamination structure, the heat-resistant composite material of the present invention is laminated in the direction in which the ceramic blankets covering the plane of the shaped refractory overlap, and a layer made of the ceramic blanket and a layer made of the shaped refractory are continuously formed in the lamination direction. Moreover, on three sides other than one side covered with the ceramic blanket, the ceramic blanket and the shaped refractory are butted in a flush state to form the same plane, and further, an example is a product manufactured such that the length in the lamination direction is 150 mm or more.

[0032] When considering the reduction of the heat capacity when the heat-resistant composite material of the present invention is used as a furnace material for a heating furnace, the higher the usage ratio of the ceramic blanket, the lighter and more effective it is. On the other hand, in that case, the volume shrinkage during heating also becomes larger, and there is a tendency that it becomes difficult to use as a furnace material. Therefore, it is preferable to manufacture the heat-resistant composite material such that, by volume ratio (volume %), the ceramic blanket is in the range of 30% to 70% and the shaped refractory 2 is in the range of 70% to 30%. Furthermore, as described above, it is more preferable that, by volume ratio, the ceramic blanket (high-alumina-containing fiber) is 60% to 40% and the shaped refractory is 40% to 60%. It is even more preferable that the ceramic blanket is 60% to 50% and the shaped refractory is 40% to 50%.

[0033] Finally, when assuming the use of the heat-resistant composite material of the present invention as a furnace material for a heating furnace, considering the workability for the furnace and the like, for example, the shape of the ceramic blanket 1 or the shaped refractory 2 which are the forming materials of the composite, the shape of a single composite, the balance of the forming materials, the number of laminations and the lamination structure of the heat-resistant composite material of the present invention which is a single composite are adjusted to be in the shape of a block composed of a cube of 300 mm × 300 mm × 300 mm, which is preferable.

[0034] <Anti - detachment pin>: As a preferred form of the heat - resistant composite material of the present invention, as shown in FIG. 2, for example, a plurality of single complexes having the shape shown in FIG. 1A are laminated to form a block - shaped laminate 3. In that case, as shown in FIG. 3B, in order to prevent the shaped refractory 2 from detaching from the block - shaped laminate 3 which is a laminate, it is preferable to adopt a structure in which the laminate 3 is provided with anti - detachment pins 5. In that case, as shown in FIG. 3B, the anti - detachment pins 5 are arranged so as to penetrate both the ceramic blanket 1 and the shaped refractory 2, and it is more preferable that the anti - detachment pins 5 are fixed at both ends. That is, by passing and fixing the anti - detachment pins 5 not only through the shaped refractory 2 but also through the ceramic blanket 1, for example, even when cracks occur in the shaped refractory 2, it is effectively prevented that fragments fall off (drop) into the furnace. Therefore, if configured as described above, it becomes possible to apply the heat - resistant composite material to the ceiling of the heating furnace, and the durability of the heat - resistant composite material constructed on the ceiling of the heating furnace can be improved.

[0035] The material of the anti - detachment pin 5 used above is not particularly limited. However, since the anti - detachment pin 5 is assumed to reach around 600 °C during the operation of the heating furnace, it is preferably a material having high heat resistance. For example, metals etc. can be mentioned, and for example, heat - resistant metals such as SUS310S and Inconel can be used. However, it is not limited to this.

[0036] Also, the shape of the anti-drop pin 5 used above is not particularly limited. For example, it can be a round bar shape, a square bar shape, etc., and among them, a round bar shape is preferably used. The size of the anti-drop pin 5 should be appropriately selected and used according to the size of the heat-resistant composite material, etc., as long as it has the strength to fix the ceramic blanket 1 and the shaped refractory 2. For example, when the heat-resistant composite material of the present invention is in the shape of a cube with a side length of about 300 mm, it is preferable to use one with an outer diameter of 6 to 12 mmφ and a length of 260 to 290 mm. The number of anti-drop pins 5 is not particularly limited either, and only the number required to fix each component can be used and installed at the desired position. That is, each component can be fixed by using at least one anti-drop pin 5. For example, as shown in FIG. 3B, in order to fix each component more stably, it is more preferable to use two or more anti-drop pins 5.

[0037] The arrangement method of the anti-drop pin 5 is not particularly limited. For example, a method can be mentioned in which a through hole for inserting the pin is formed in the laminate in advance, and the anti-drop pin 5 is inserted and arranged in the through hole. However, when the anti-drop pin 5 has sufficient strength, a method can be adopted in which the anti-drop pin 5 is directly stabbed and arranged on the laminate without providing the through hole in the laminate in advance.

[0038] Also, as shown in FIG. 3B, a general L-shaped metalware can be used as the fastener of the anti-drop pin 5, but it is not particularly limited. Furthermore, the L-shaped metalware is also used to attach the wall surface of the can body 4 of the heating furnace and the fixing pin 5 for fixing the heat-resistant composite material, but both are general ones and are not particularly limited in this regard either.

[0039] <Example of Application of Heat-Resistant Composite Material to Furnace Wall> FIG. 4 is an example of using the heat-resistant composite material 3 of the present invention as the inner lining material of a heating furnace. By arranging a plurality of heat-resistant composite materials along the entire inner wall of the can body 4 of the heating furnace, it is used as a furnace wall. In addition, the heat-resistant composite material of the present invention can be stacked as shown in FIG. 5. In the case of the stacking method shown in FIG. 5, the ceramic blanket 1 and the shaped refractory 2 constituting the heat-resistant composite material 3 are arranged in a straight line in the vertical direction and stacked to form a fireplace. The heat-resistant composite material 3 of the present invention can be stacked as shown in FIG. 6. In the case of the stacking method shown in FIG. 6, the positions of the shaped refractories 2 constituting the laminate between adjacent heat-resistant composite materials 3 are arranged alternately in the vertical and horizontal directions to form a fireplace. As described above, the stacking method of the heat-resistant composite material 3 of the present invention as a furnace material can be appropriately selected according to the material of the shaped refractory 2 and the operating conditions of the heating furnace, and is not particularly limited.

[0040] <Method for manufacturing heat-resistant composite material> An example of the method for manufacturing the heat-resistant composite material of the present invention will be described with reference to the drawings. The single body of the heat-resistant composite material of the present invention, as shown in FIGS. 1A and 1B, covers one side surface and two plane surfaces of a hexahedral shaped refractory 2 manufactured by a general refractory manufacturing method with a sheet-shaped ceramic blanket 2, and the other three side surfaces of the shaped refractory 2 are exposed and compounded. By doing so, as shown in FIGS. 1A and 1B, on the three exposed side surfaces of the shaped refractory 2 other than the one side surface covered with the ceramic blanket 1, the end surface of the ceramic blanket 1 and the end surface of the shaped refractory 2 are butted in a flush state to form the same plane. In order to easily obtain the single body of the heat-resistant composite material of the present invention having the above-described configuration, it is necessary to make the width of the sheet-shaped ceramic blanket 2 the same as the length of the vertical or horizontal side of the plane of the hexahedral shaped refractory 2.

[0041] Next, a case where a block-shaped laminate is formed using a plurality of the above-described heat-resistant composite materials of the present invention will be described. As shown in FIG. 2, by laminating a plurality of ceramic blankets that cover the plane of the shaped refractory 2 so as to butt against each other using a plurality of the heat-resistant composite materials of the present invention obtained as described above, a block-shaped heat-resistant composite material having a laminated structure can be easily produced. In the example shown in FIG. 2, six heat-resistant composite materials of the present invention in a single form were used to produce a laminate with a length in the stacking direction of 150 mm or more.

[0042] Furthermore, as shown in FIG. 3B, a through hole (not shown) was formed in the heat-resistant composite material 3 produced as shown in FIG. 2, and a dropout prevention pin 5 was inserted into the through hole so that six heat-resistant composite materials of the present invention in a single form were fixed in a stacked state. In the example shown in FIG. 3B, the dropout prevention pin 5 is fastened and fixed by an L-shaped metal fitting, and with such a configuration, the heat-resistant composite material 3 formed by laminating six single forms is prevented from dropping out and can be firmly fixed to the can body of the heating furnace.

[0043] <Use of the heat-resistant composite material> The heat-resistant composite material of the present invention is suitable as a lining furnace material for fireproof and heat insulation purposes, and can be effectively used, for example, as a material for the furnace wall of a heating furnace heated to 1600 ° C or higher.

Examples

[0044] Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited only to the configurations of the following examples.

[0045] (Example 1) As Example 1, a block-shaped heat-resistant composite material having a laminated structure shown in FIG. 2, in which four single heat-resistant composite materials shown in FIG. 1A are laminated, was produced. The single heat-resistant composite material used above was designed such that the ceramic blanket 1 and the shaped refractory 2 had a volume ratio shown in Table 1, and a composite was produced as shown in FIG. 1A. The shaped refractory 2 used at this time was a flat plate having a length of 300 mm × width of 300 mm × thickness of 25 mm. Further, as the ceramic blanket 1, a sheet-like material having a thickness of 25 mm and a shape (size) capable of covering two planes of the shaped refractory 2 with a length of 300 mm × width of 300 mm and one side surface of 300 mm × 25 mm was used. In the heat-resistant composite material having the laminated structure obtained above, the material compositions of the ceramic blanket 1 and the shaped refractory 2 occupied 70% and 30% respectively by volume ratio for the ceramic blanket 1 and the shaped refractory 2.

[0046] In the above, for the ceramic blanket 1, one having a heat-resistant temperature of 1600 °C, a bulk density of 200 kg / m 3 and a volume shrinkage rate of 3% due to heating at 1600 °C was used. Further, for the shaped refractory 2, one having a heat-resistant temperature of 1600 °C, a bulk density of 2000 kg / m 3 and a residual linear expansion rate of 3% in the cooling process from the heating state at 1600 °C to the room temperature state was used. Then, by laminating four single heat-resistant composite materials prepared using the above ceramic blanket 1 and shaped refractory 2, a substantially cubic heat-resistant composite material having dimensions of 300 mm × 325 mm × 300 mm was produced. This was used as the block-shaped heat-resistant composite material having the laminated structure of Example 1.

[0047] (Examples 2 to 5) In Examples 2 to 5, materials having the same characteristics as the above-described ceramic blanket 1 and shaped refractory 2 used in the production of the block-shaped heat-resistant composite material having the laminated structure of Example 1 were used respectively. Then, in the same manner as in Example 1 except that the thicknesses of the ceramic blanket 1 and the shaped refractory 2 were changed, block-shaped heat-resistant composite materials in which the material compositions of the ceramic blanket 1 and the shaped refractory 2 were 60:40, 50:50, 40:60, and 30:70 in volume ratio (volume %) were produced respectively. These were made into block-shaped heat-resistant composite materials having the laminated structures of Examples 2 to 5.

[0048] (Comparative Example 1) In Comparative Example 1, a material consisting only of a shaped refractory having the same characteristics (material) as the shaped refractory used in Example 1 and having a shape of 300 mm × 325 mm × 300 mm was used.

[0049] (Evaluation) Using the heat-resistant composite materials of Examples 1 to 5 produced as described above as furnace materials for a heating furnace, the furnace wall of a test heating furnace was constructed in the stacking method shown in FIG. 6. Also, a shaped refractory only of Comparative Example 1 was used as a furnace material, and it was constructed as a furnace wall in a heating furnace in the same manner as in the case of the examples. After constructing the furnace walls of the heating furnace using the materials of each example and comparative example as furnace materials respectively, the inside of each furnace was heated to 1600° C. over about 32 hours, the temperature was maintained at 1600° C. for 4 hours, and it was cooled to room temperature over about 40 hours. Then, the fuel consumption required for heating was measured for each example, and the relative fuel consumption index calculated based on the fuel consumption measured in the heating furnace constructed with the furnace material of Comparative Example 1 is shown in Table 1. Also, for the four furnace materials with the same arrangement constructed inside each heating furnace, for each heat-resistant composite material (furnace material) of Examples 1 to 5, the thicknesses in the stacking direction of each heat-resistant composite material arranged at the above four locations before and after heating were measured respectively. For the furnace material consisting only of the shaped refractory of Comparative Example 1, the thicknesses in the same direction as the furnace material of the example were measured respectively. Then, the dimensional change rate was calculated from the average dimensions of the four measured furnace materials, and the results are shown in Table 1. Shrinkage was shown as a negative numerical value, and expansion was shown as a positive numerical value.

[0050] TIFF2025084494000002.tif71170

[0051] As shown in Table 1, it was confirmed that in all examples, the fuel consumption of the heating furnace could be reduced by using the furnace lining materials of the examples compared with the furnace lining composed only of the shaped refractory of Comparative Example 1. That is, it was found that by applying the heat-resistant composite material of the present invention to the furnace lining of the heating furnace, the heating efficiency of the heating furnace could be improved. Further, as shown in Table 1, the dimensional change rate before and after heating when the heat-resistant composite material of the example of the present invention was used as the furnace lining was remarkably improved compared with the case where the furnace lining composed only of the shaped refractory of Comparative Example 1 was used. And it was assumed that there would be no fire leakage during the operation of the heating furnace as long as it was within the range of the dimensional change rate in Examples 1 to 5 this time. In particular, considering the reduction of the dimensional change rate, it was found that it was effective to set the material ratio of the ceramic blanket (high alumina-containing fiber aggregate) and the shaped refractory at 60 - 40:40 - 60 in volume %. Also, considering the reduction of fuel consumption, it was found that it was more preferable to set the material ratio of the ceramic blanket and the shaped refractory at about 60 - 50:40 - 50 in volume %.

Explanation of Signs

[0052] 1: Aggregate of high alumina-containing fibers (ceramic blanket) 2: Hexahedral shaped refractory 3: Block-shaped heat-resistant composite material having a laminated structure 4: Shell of the heating furnace 5: Anti-drop pin

Claims

1. A heat-resistant composite material used as a lining refractory material for heat resistance and heat insulation, which is a composite body in which an aggregate of high-alumina-containing fibers containing 70% or more of alumina by mass ratio, which is a heat-resistant material, and a hexahedral shaped refractory used as a lining refractory material of a heating furnace are combined and integrated, wherein one side surface and two flat surfaces of the hexahedral shaped refractory are covered with the aggregate, and the other three side surfaces are exposed and combined, and on the three side surfaces other than the one side surface covered with the aggregate, the end surface of the aggregate and the end surface of the refractory are butted in a flush state to form the same plane. The heat-resistant composite material is characterized by this.

2. Furthermore, it is a block-shaped heat-resistant composite material having a laminated structure in which a plurality of the composite bodies are laminated, and the laminated structure is laminated in a direction in which the aggregates covering the flat surfaces overlap, and in the lamination direction, a layer composed of the aggregate and a layer composed of the shaped refractory are continuously formed, and on the three side surfaces other than the one side surface of the shaped refractory covered with the aggregate, the end surface of the aggregate and the end surface of the refractory are butted in a flush state to form the same plane, and the length in the lamination direction is 150 mm or more. The heat-resistant composite material according to Claim 1.

3. The heat-resistant composite material according to Claim 1 or 2, wherein the use temperature of the aggregate is 1600°C or higher, and the use temperature of the shaped refractory is 1600°C or higher.

4. The integrated body has a bulk density of 200 kg / m ３ is a blanket made of the following high alumina-containing fibers, and the bulk density of the shaped refractory is 2000 kg / m ３ The heat-resistant composite material according to claim 1 or 2, wherein the bulk density is 2000 kg / m or less.

5. The heat-resistant composite material according to Claim 1 or 2, wherein the shaped refractory is a material that expands upon heating and exhibits a high residual linear expansion rate during the firing process from room temperature to a heated state of 1600°C or higher and back to room temperature.

6. The heat-resistant composite material according to Claim 1 or 2, wherein the material composition of the composite body is 30 to 70% of the high-alumina-containing fiber and 30% to 70% of the shaped refractory by volume ratio.

7. The heat-resistant composite material according to Claim 1 or 2, wherein the shape of the composite body is 50 to 350 mm in length, 50 to 350 mm in width, and 50 to 300 mm in thickness.

8. Furthermore, a dropout prevention pin is provided to prevent the shaped refractory from dropping out of a block-shaped heat-resistant composite material having a laminated structure in which a plurality of the composite bodies are laminated, and the dropout prevention pin is arranged in a state of penetrating both the aggregate and the shaped refractory constituting the plurality of laminated composite bodies. The heat-resistant composite material according to Claim 2.

9. A furnace wall made of a refractory and heat-insulating inner lining furnace material, wherein a plurality of the heat-resistant composite materials according to claim 1 or 2 are used as the refractory and heat-insulating inner lining furnace material, and the laminate is arranged on the inner side of the furnace. A furnace wall characterized by being configured as described above.

10. The furnace wall according to claim 9, wherein the plurality of heat-resistant composite materials are arranged such that the shaped refractories constituting the laminate are arranged in a straight line in the vertical direction, or the positions of the shaped refractories constituting the laminate between adjacent heat-resistant composite materials are arranged alternately in the vertical and horizontal directions.

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