JP2001080969A - Nonlithic refractory raw material and monolithic refractries - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve corrosion resistance, executability and safety at a low cost by specifying a composition consisting of fine ceramic powder containing fine aluminous powder, on aluminous or silicon carbide refractory aggregate, nickel oxide powder or nickel powder and a hydraulic binder. SOLUTION: Monolithic refractories are obtained by firing the kneaded matter obtained by adding water to a raw material consisting of the refractory aggregate, the fine ceramic powder, the nickel oxide powder or the nickel powder and the hydraulic binder. The fine ceramic powder consists of 8 to 26.5 wt.% fine aluminous powder and 0.5 to 10% fine silica powder. The overage grain size thereof is 0.1 to 50 μm. The nickel oxide or nickel powder to improve the corrosion resistance to slag is specified to a content of 0.17 to 18% in terms of NiO and the average grain size thereof is specified to 0.1 to 100 μm. The refractory aggregate preferably contains aluminous material, and further, silicon carbide material is incorporated at need therein. The content thereof is specified to 48 to 80%. The hydraulic binder is preferably hydraulic alumina and the content thereof is specified to 2 to 10%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous refractory raw material based on alumina-nickel oxide and silicon carbide-alumina-nickel oxide having excellent corrosion resistance to slag, and an amorphous refractory produced from the refractory raw material. It is about things.

[0002]

2. Description of the Related Art Conventionally, an alumina-based amorphous refractory having alumina aggregate as a main component and a silicon carbide having silicon carbide aggregate as a main component, using alumina cement as an inorganic binder as an amorphous refractory. Amorphous refractories are known. Both alumina-based amorphous refractories and silicon carbide-based amorphous refractories have excellent heat resistance. In particular, silicon carbide-based amorphous refractories have low permeability to basic molten slag and have excellent corrosion resistance. These refractories are widely used as blast ladle refractories.

In recent years, the use of the above-mentioned irregular refractories as refractories for melting furnaces has been considered. However, since the refractory for a melting furnace is in direct contact with the basic molten slag, the requirements for corrosion resistance are more stringent than those for a blast ladle. For this reason, even if the conventional amorphous refractory is a silicon carbide-based amorphous refractory having relatively excellent corrosion resistance, the corrosion resistance is not sufficient as a refractory for a melting furnace.

As a solution to such a problem, Japanese Patent Application Laid-Open No. 9-278540 discloses a silicon carbide-based amorphous refractory obtained by adding carbon and cobalt oxide and calcining the refractory. According to this, the corrosion resistance can be further improved. However, since the cobalt oxide used in the refractory is expensive, there is a problem that the amorphous refractory to be manufactured is also expensive.

[0005]

As a method of improving the corrosion resistance without using cobalt oxide, for example, magnesia or chromia, which is already used for an alumina-based irregular refractory and imparts high corrosion resistance to the refractory, is replaced with a silicon carbide-based refractory. It is conceivable to mix it with irregular shaped refractories. However, silicon carbide-based amorphous refractories obtained by blending magnesia are 14
Since a low-melting point compound is generated at a temperature lower than 00 ° C., there is a problem that the heat resistance of the refractory decreases.

In general, silicon carbide-based amorphous refractories generate carbon dioxide or carbon monoxide and further generate silicon oxide by reacting a silicon component with oxygen in a high-temperature atmosphere. Therefore, there is a problem that the corrosion resistance is reduced.

[0007] Further, although the silicon carbide-based amorphous refractory obtained by blending chromia has high corrosion resistance, there is a concern that hexavalent chromium is generated during use, and its use is not preferable from the viewpoint of environmental protection. This is a problem pointed out similarly for alumina-based amorphous refractories obtained by blending chromia.

On the other hand, as an alumina-based amorphous refractory excellent in heat resistance and corrosion resistance, for example, Japanese Patent Publication No. 6-8224
In the official gazette, a predetermined refractory material, an ultrafine powder of silica or the like, and a refractory composition comprising hydraulic alumina contained in the ultrafine powder, a cement-free amorphous refractory raw material added with a dispersant, It has been disclosed.

According to this refractory raw material, corrosion resistance and fire resistance of the obtained refractory are improved, and workability such as fluidity and curability is enhanced. However, since the refractory raw materials and the like have a narrow range of conditions suitable for curing, they are easily affected by the temperature and humidity at the kneading site and the mixing ratio of the compounding materials such as aggregate during the application, and the workability is sufficient. There was a problem that was not. Specifically, hydraulic binders generally have a tendency to decrease in fluidity during kneading, and are also susceptible to poor curing when the temperature at the kneading site during construction is low, and to cure too quickly when the temperature is high. There is a problem that the fluidity at the time is rapidly reduced.

That is, conventionally, there has been no known amorphous refractory which has excellent corrosion resistance, is inexpensive, has excellent workability at the time of production, and has high safety.

Accordingly, an object of the present invention is to provide an amorphous refractory which is low in cost, has excellent corrosion resistance, is excellent in workability at the time of production, has high safety, and a raw material of an amorphous refractory which can be manufactured with the refractory. Is to do.

[0012]

Under such circumstances, the present inventors have conducted intensive studies and as a result, have used fire-resistant aggregate and ceramic fine powder, and used nickel oxide or nickel powder as an additive for improving the corrosion resistance. According to the refractory raw material using a hydraulic binder as a binder, the obtained amorphous refractory is excellent in corrosion resistance at low cost,
The present inventors have found that the workability during production is excellent and the safety is further improved, and the present invention has been completed.

In addition, the present inventor has found that in the refractory raw material, according to the refractory raw material in which the ceramic fine powder contains alumina fine powder, the obtained amorphous refractory contains alumina having a spinel structure similar to that of the refractory raw material. -Nickel oxide compound (hereinafter, "spinel type alumina-Nickel oxide compound")
) Is produced, so that it is less expensive, has excellent corrosion resistance, is excellent in workability at the time of production, and has higher safety.

That is, the present invention provides an irregular-shaped refractory raw material comprising refractory aggregate, ceramic fine powder, nickel oxide powder or nickel powder, and a hydraulic binder. .

Further, the present invention provides an amorphous refractory raw material, wherein the ceramic fine powder contains alumina fine powder in the amorphous refractory raw material.

The present invention also provides an amorphous refractory obtained by adding water to the amorphous refractory raw material to form a kneaded product, and firing the kneaded product.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The amorphous refractory raw material according to the present invention is an amorphous refractory raw material containing a refractory aggregate, ceramic fine powder, nickel oxide powder or nickel powder, and a hydraulic binder. .

The refractory aggregate used in the present invention includes alumina-based refractory aggregate, silicon carbide-based refractory aggregate, or both of them. Among these, alumina-based refractory aggregate is preferable because it reacts with nickel oxide to generate a spinel-type alumina-nickel oxide compound and increases the corrosion resistance of the amorphous refractory. When only a silicon carbide refractory aggregate is used as the refractory aggregate, when a ceramic fine powder containing alumina fine powder described later is used, alumina and nickel oxide in the refractory raw material are used as a spinel. Since a type-alumina-nickel oxide compound is generated, the corrosion resistance of the refractory obtained is preferably high.

Examples of the material of the alumina refractory aggregate include one or more selected from high-purity alumina, alumina silica, mullite, bauxite, and chamotte. Here, alumina silica refers to a composition mainly including an alumina component and a silica component in a broad sense, and mullite refers to a mullite material containing an alumina component and a silica component in a predetermined blending ratio. Say. The above-mentioned alumina-based refractory aggregate may contain other components in addition to the alumina-based, but those containing a higher proportion of the alumina-based are preferred from the viewpoint of heat resistance (fire resistance). Examples of the material of the silicon carbide refractory aggregate include silicon carbide for refractories having a purity of 80% or more. The above-mentioned alumina refractory aggregate or silicon carbide refractory aggregate is one or two kinds.
It can be used in combination of more than one kind.

As the refractory aggregate, those having a particle size exceeding 50 μm are used, and any material having a particle size within this range may be used. In addition, it is preferable to use a combination of materials having different particle diameters, because the internal structure of the obtained refractory becomes denser, the fluidity of the kneaded material is improved, and the material can be easily poured into the construction site.

For example, the refractory aggregate is composed of a coarse-grained material having a particle size of more than 1 mm and 3 mm or less, a fine-grained material having a particle size of more than 0.15 mm and 1 mm or less, and a fine-grained material having a particle size of more than 0.15 mm and 1 mm or less. When it is a combination of a powder material of 0.15 mm or less, the coarse material forms a skeleton of the refractory, the fine material fills the gap between the coarse materials, and the powder material is a coarse material and a fine material. It acts as a lubricant to increase the denseness of the refractory obtained by further filling the gaps between the materials and to increase the fluidity of the kneaded material,
In addition, the refractory aggregate as a whole is preferable because the internal structure of the obtained refractory is densified, the fluidity of the kneaded material is improved, and it is easy to pour into the construction site.

The amount of the refractory aggregate to be incorporated is preferably 48 to 80% by weight in the amorphous refractory raw material. When the refractory aggregate is composed of a coarse-grained material, a fine-grained material, and a powdered material, the coarse-grained material is preferably 25 to 45% by weight, more preferably 28 to 40% by weight in the amorphous refractory raw material. The fine particles are preferably 15 to 35% by weight, more preferably 20 to 30% by weight, and the powders are preferably 4 to 2% by weight.
5% by weight, more preferably 5 to 22% by weight. When the coarse-grained material, fine-grained material and powder material are blended in the above ratio, the internal structure of the obtained refractory is densified,
It is preferable because the fluidity of the kneaded material is improved and the kneaded material is easily poured into the construction site.

The ceramic fine powder used in the present invention is used for improving the workability of the kneaded material obtained by adding water to the amorphous refractory raw material, that is, increasing the fluidity and water retention of the kneaded material, It is for lowering. Examples of the ceramic fine powder include fine powders of alumina, silica, titania, zirconia, silicon carbide, and the like.

Examples of the material of the alumina fine powder include the same materials as the above alumina refractory aggregate. For example, one or more selected from high-purity alumina, alumina silica, mullite, bauxite and chamotte Is mentioned. The alumina fine powder may contain other components besides alumina, but those containing alumina at a higher ratio are preferable from the viewpoint of heat resistance (fire resistance). Examples of the material of the silicon carbide fine powder include the same materials as the above-mentioned silicon carbide refractory aggregate, for example, silicon carbide for refractories having a purity of 80% or more.

Of the ceramic fine powders, alumina fine powders are preferred because they impart fluidity to the kneaded material and form a spinel-type alumina-nickel oxide compound by reacting with nickel oxide. Further, the silica fine powder is preferable because it imparts fluidity and water retention to the kneaded material and ensures sufficient strength of the refractory after heating. further,
The combination of the alumina fine powder and the silica fine powder has high fluidity and water retention of the kneaded material, the alumina fine powder generates a spinel-type alumina-nickel oxide compound, and the silica fine powder heats the refractory. It is more preferable to make the strength afterward sufficient. The ceramic fine powder,
One type or a combination of two or more types can be used.

The ceramic fine powder has an average particle size of 0.1
To 50 μm, preferably 0.1 to 30 μm, more preferably 0.1 to 10 μm. When the average particle size is in the above range, the internal structure of the obtained refractory is densified, and the fluidity of the kneaded material is improved, so that it is easy to pour the material into the construction site. The average particle size of the alumina fine powder is within the above range, and the average particle size is different from that of the alumina refractory aggregate. Classified as one of high quality refractory aggregates. Since the alumina fine powder has an average particle size smaller than that of the alumina-based refractory aggregate, the alumina-based powder easily fills the gaps between the refractory aggregates during firing of the amorphous refractory. For this reason, it is preferable because it reacts with the nickel oxide in the gap to generate a spinel-type alumina-nickel oxide compound having a high corrosion resistance, and can more effectively suppress slag immersion generally generated in the gap.

[0027] The ceramic fine powder is preferably 12 to 27% by weight, more preferably 1 to 27% by weight in the raw material of the amorphous refractory.
It is contained in an amount of 4 to 27% by weight. If the content of the ceramic fine powder is less than 12% by weight, the fluidity and water retention of the kneaded product of the amorphous refractory raw material are not sufficient, which is not preferable. It is not preferable to increase the amount of kneading water to impart fluidity and water retention to the kneaded material in this state, because the refractory aggregate and the ceramic fine powder are easily separated. If the amount of the fine ceramic powder exceeds 27% by weight, the fluidity of the kneaded material of the amorphous refractory material when vibration is applied is improved, but the viscosity of the kneaded material is excessively increased and the workability is deteriorated. Is not preferred.

When the ceramic fine powder is a combination of alumina fine powder and silica fine powder, the amount of the alumina fine powder in the amorphous refractory raw material is preferably from 8 to 26.
5% by weight, more preferably 10 to 25% by weight, and the amount of the silica fine powder is preferably 0.5 to 10% by weight, more preferably 1.5 to 7% by weight. When the blending amount of the alumina fine powder and the silica fine powder is within the above range, a kneaded product having an excellent balance of fluidity, water retention and viscosity can be obtained.

The nickel oxide powder or nickel powder used in the present invention is for imparting corrosion resistance to slag to an amorphous refractory. Among these, as the nickel oxide powder, for example, a powder of 75% by weight or more in terms of nickel used for catalyst, glass coloring, enamel, ceramic glaze, ferrite material and the like can be mentioned. Examples of the nickel powder include a powder that generates nickel oxide by heating in an oxidizing atmosphere. Here, the heating in the oxidizing atmosphere includes, for example, heating in the firing step of the kneaded molded product in the air, drying, or heating when the refractory after firing is used in the furnace. .

The nickel oxide powder or nickel powder has an average particle size of 0.1 to 100 μm, preferably 0.3 to 30 μm.
μm is used. When the average particle size is within the above range, nickel oxide or nickel oxide generated by oxidation of nickel powder during firing or the like reacts with alumina fine powder or alumina aggregate to effectively produce spinel type alumina. -It is preferable because a nickel oxide compound is generated and the erosion resistance of the amorphous refractory to slag is increased.

The nickel oxide powder or nickel powder is N
The weight in terms of iO is preferably 0.7 to 18% by weight, more preferably 1 to 15% by weight, particularly preferably 1.5 to 5% by weight, and still more preferably 1.8 in the amorphous refractory raw material. -4.5% by weight.

When the amount is less than 0.7% by weight,
It is not preferable because the corrosion resistance of the obtained refractory is not sufficiently improved. Further, if the amount is 0.7% by weight or more and less than 1.8% by weight, the amount of the compounded amount may be small and the stability of quality may be reduced. More preferably, the amount is 1.8% by weight or more. On the other hand, if the amount is more than 18% by weight, the effect of improving corrosion resistance is not improved beyond a certain level, which is uneconomical, and the molded body expands greatly at the time of firing and cracks easily occur in the construction body, which is not preferable.

FIG. 5 shows an example of the relationship between the amount of nickel oxide powder added, the erosion index, and the average pore diameter in the alumina-nickel oxide-based irregular refractory among the irregular refractories according to the present invention. From FIG. 5, it can be seen that the higher the mixing ratio of the nickel oxide powder, the higher the corrosion resistance of the amorphous refractory and the smaller the average pore diameter. Accordingly, the corrosion resistance of the amorphous refractory, particularly the corrosion resistance of the alumina-nickel oxide-based irregular refractory, is determined by reacting alumina and nickel oxide to form a spinel-type alumina-nickel oxide compound. It is thought that the pore diameter becomes smaller and the molten slag has a structure that is hardly eroded, thereby improving the structure.

The hydraulic binder used in the present invention is not particularly limited, and examples thereof include hydraulic alumina and alumina cement. Among them, hydraulic alumina is not particularly reduced in corrosion resistance even when an amorphous refractory obtained without containing CaO is repeatedly used at a high temperature, and an alumina component reacts with nickel oxide to form a spinel-type alumina-nickel oxide. It is preferable because it contributes to the formation of a compound. The hydraulic binder has an average particle size of 1 to 20 μm.
m, preferably 10 to 15 μm. It is preferable that the average particle size is within the above range, since the workable fluidity can be maintained for 30 minutes or more after kneading.

The hydraulic binder is contained in the amorphous refractory raw material in an amount of preferably 2 to 10% by weight, more preferably 2 to 5% by weight. If the compounding amount of the hydraulic binder is less than 2% by weight, poor curing may occur when the temperature at the time of construction is low, and if it exceeds 10% by weight, curing may occur at a high temperature during construction. It is not preferable because it is too early and the fluidity at the time of kneading may suddenly decrease.

The amorphous refractory raw material according to the present invention may further contain an organic fiber and a dispersant as appropriate. Examples of the organic fiber include polypropylene, acrylic, rayon, nylon, and vinylon, and these can be used alone or in combination of two or more. It is preferable to mix organic fibers because explosion of the construction body during rapid heating can be prevented. The compounding amount of the organic fiber is 0.04 to 0.1 part by weight based on the total amount of the refractory aggregate, nickel oxide powder or nickel powder in terms of NiO, and the total amount of the ceramic fine powder and the hydraulic binder of 100 parts by weight. is there.

Examples of the dispersant include a metal chelate compound, an alkali metal carbonate, a condensed salt of aromatic sulfonic acid and formalin, and these can be used alone or in combination of two or more. It is preferable to add a dispersant, since the fluidity of the kneaded material in a low water amount is improved and kneading becomes possible. The amount of the dispersant is 0.05 to 0.5 parts by weight, based on the total amount of the refractory aggregate, nickel oxide powder or Ni powder in terms of NiO, and the total amount of the ceramic fine powder and hydraulic binder of 100 parts by weight. is there. It is preferable that the compounding amount of the dispersant is within the above range, since the fluidity of the kneaded material of the amorphous refractory raw material is maintained for a long time. The amorphous refractory raw material according to the present invention is obtained by mixing and mixing the refractory aggregate, nickel oxide powder or nickel powder, ceramic fine powder and hydraulic binder, and, if necessary, organic fiber or dispersant. . These various raw materials may be mixed once or in a plurality of times, and when mixing in a plurality of times, the order of mixing does not matter.

The amorphous refractory raw material according to the present invention may further contain one or more selected from zirconia, titania, manganese oxide and cobalt oxide in order to further enhance the corrosion resistance of the refractory. Good.

In the amorphous refractory raw material according to the present invention, it is preferable that at least the ceramic fine powder contains alumina fine powder, and the ceramic fine powder contains alumina fine powder, and the refractory aggregate is alumina-based refractory bone. It is more preferable to include a material. If the amorphous refractory raw material contains alumina fine powder, the alumina fine powder is easily filled into the gaps between the refractory aggregates during firing of the amorphous refractory, and during firing or in the melting furnace. When using, for example, the nickel oxide reacts with the nickel oxide in the gap to produce a highly corrosion-resistant spinel-type alumina-nickel oxide compound. Is more preferred. In addition, when alumina-based refractory aggregate is further included in addition to alumina-based fine powder, when the alumina-based refractory aggregate is particularly a powdered material, the spinel is formed in a void formed by the coarse-grained or fine-grained material. Since a type-alumina-nickel oxide compound is generated, corrosion resistance is further improved, which is preferable.

When the amorphous refractory raw material according to the present invention contains alumina fine powder, the amorphous refractory raw material usually contains 8 to 27% by weight of alumina fine powder and nickel oxide powder or nickel powder in terms of NiO. Contains 0.7 to 18% by weight and 2 to 10% by weight of a hydraulic binder, preferably 10 to 25% by weight of alumina fine powder, and 1 to 15% by weight of nickel oxide powder or nickel powder in terms of NiO. And 2 to 5% by weight of a hydraulic binder. It is preferable that the alumina fine powder and the nickel oxide powder or the like be contained in the above ratio, since a spinel-type alumina-nickel oxide compound is easily generated and the corrosion resistance becomes higher.

When the amorphous refractory raw material according to the present invention contains alumina fine powder and also contains alumina refractory aggregate, the amorphous refractory raw material usually contains 8 fine alumina powder.
To 27% by weight, alumina-based refractory aggregate is 48 to 80% by weight, nickel oxide powder or nickel powder is 0.7 to 18% by weight in terms of NiO, and hydraulic binder is 2 to 10% by weight.
Preferably, it contains 10 to 25% by weight of alumina fine powder, 55 to 80% by weight of alumina refractory aggregate, 1 to 15% by weight of nickel oxide powder or nickel powder in terms of NiO, and 2 parts of hydraulic binder. -5% by weight. It is preferable that the alumina fine powder, the alumina refractory aggregate, the nickel oxide powder, and the like be contained in the above ratio because a spinel-type alumina-nickel oxide compound is easily generated and the corrosion resistance is further increased.

The irregular refractory according to the present invention is obtained by adding water to the above-mentioned irregular refractory raw material to form a kneaded product, and then firing the kneaded product. At this time, the amount of water to be added is usually 4 to 7 parts by weight of water with respect to 100 parts by weight of the above-mentioned amorphous refractory raw material,
Preferably it is 5 to 6 parts by weight. If the added amount of water is less than 4 parts by weight, the fluidity of the kneaded material is low, and kneading tends to be difficult, which is not preferable. If it exceeds 7 parts by weight, the fluidity of the kneaded material becomes too high, and It is not preferable because the ceramic fine powder is easily separated.

The kneaded material is prepared by using, for example, a mixer. The amorphous refractory according to the present invention is excellent in fluidity because it is obtained by kneading the above-mentioned amorphous refractory raw material and water in the above-mentioned mixing ratio when kneaded. Further, since the dispersing agent is further blended in an amount within the above range, especially the fluidity of the kneaded material is maintained long, and the usable time is prolonged.

The irregular refractory according to the present invention is obtained by appropriately molding, drying and firing the above kneaded material. For example, the kneaded material is molded in a mold to obtain a molded product having a predetermined shape, and then dried and fired to obtain an amorphous refractory.
As a forming method, for example, vibration casting into a form at a construction site or thick coating can be used. Drying is performed, for example, at 80 to 120 ° C. for 17 to 24 hours. The firing is performed, for example, at 1200 to 1500 ° C. for 5 to 24 hours. In addition, the amorphous refractory according to the present invention can be applied to an inner wall or the like of a melting furnace as a dry body without providing the above-described firing step for producing a refractory, and the heat generated when the melting furnace is used. By baking substantially. In addition,
The organic fibers and dispersant incorporated as needed are burned off after firing and do not exist in the amorphous refractories.

The amorphous refractory according to the present invention has excellent corrosion resistance and heat resistance. In particular, an amorphous refractory material containing alumina fine powder or an amorphous refractory obtained from an amorphous refractory material containing alumina fine powder and containing alumina refractory aggregate is a refractory material in the amorphous refractory material. Since the gap between the aggregates contains the spinel-type alumina-nickel oxide compound, it is more excellent in corrosion resistance and heat resistance. The amorphous refractory raw material according to the present invention and the amorphous refractory produced from the amorphous refractory raw material can be used for refractory for blast ladle and refractory for ash melting furnace. .

[0046]

EXAMPLES Next, the present invention will be described more specifically with reference to examples, but this is merely an example and does not limit the present invention.

Example 1 31.0 parts by weight of coarse alumina refractory aggregate having a particle size of more than 1 mm and 3 mm or less, and alumina refractory aggregate having a particle size of more than 0.15 mm and 1 mm or less Fine grain material 2
7.1 parts by weight, 10.4 parts by weight of alumina refractory aggregate powder having a particle size of more than 50 μm and 0.15 mm or less;
10.0 parts by weight of nickel oxide powder having an average particle size of 1 μm, 16.0 parts by weight of ultrafine alumina powder having an average particle size of 2 μm, 1.5 parts by weight of ultrafine silica powder having an average particle size of 0.6 μm, and average particle size 10 μm of hydraulic alumina 4.0 parts by weight total 1
0.08 parts by weight of organic fiber, 0.1 parts by weight of dispersant and 6.0 parts by weight of water were added to 00.0 parts by weight, and the mixture was kneaded with a mixer for 6 minutes. The fluidity of the obtained kneaded material was evaluated as a vibration flow value shown below. Table 1 shows the results of the compounding amount and the vibration flow value. In Table 1, the blending amounts are expressed in parts by weight. Next, the kneaded material is cast and molded, and 105
C. for 24 hours, and then calcined at 1400.degree. C. for 5 hours to obtain an amorphous refractory. The corrosion resistance of the obtained amorphous refractory was evaluated as an erosion index shown below. Table 1 shows the results.

[Measurement Method of Vibration Flow Value] First, a flow cone specified in JIS R 5201: 92 is placed on a vibration table such that the tip of the cone faces upward. The kneaded material was filled while applying vibration. next,
After the cone was slowly removed without disturbing the shape of the filled kneaded material, a 60 Hz vibration was immediately applied for 30 seconds. After the end of the vibration, the maximum value of the diameter at the bottom surface of the kneaded material that has collapsed and spread and the diameter of the portion perpendicular to the maximum value portion are measured, and the average value of the two positions is used as the vibration flow value (mm) And The larger the vibration flow value, the better the fluidity.

[Measurement method of erosion index] First, an isosceles trapezoidal column as shown in FIG. 1 (upper base of trapezoidal surface 55 mm, lower base of trapezoidal surface 130 mm, trapezoidal surface height 65 mm, trapezoidal column height 11)
A test sample A made of an amorphous refractory (5 mm) is prepared, and six samples A are combined and fixed so as to form a hexagonal column-shaped concave portion D on the six rectangular surfaces on the upper bottom side as shown in FIG. Then, a test piece B having a hexagonal column shape was formed. The numerical values in FIG. 1 indicate dimensions, and the unit is mm. Next, in a state where the specimen B is laid down sideways as shown in FIG. 2 and the specimen B is rotated by a rotating device C about an axis perpendicular to the bottom surface as shown in FIG.
, A slag E was charged into the concave portion D of the test piece B, and the test piece B was rotated at 1500 ° C. for 8 hours. After a lapse of 8 hours, the specimen B is disintegrated for each sample A, and as shown in FIG. 3, the sample A is moved from the center line ab in the longitudinal direction of the upper bottom rectangular surface contacted with the slag to the longitudinal direction of the lower bottom rectangular surface. Was cut such that a substantially rectangular cut surface abdc appeared at the center line cd of the above. Next, as shown in FIG.
The erosion area of the erosion part F by the slag of c was measured, and the erosion rate was calculated by the following formula (1). Erosion rate (%) = (Erosion area of cross section / total area of cross section) × 100 (1) Next, the erosion rate of the obtained target sample and a standard sample (calcined using conventional alumina cement as a binder) The erosion index was calculated by the following equation (2) from the erosion rate of the irregular shaped refractory). About the composition and physical properties of the standard sample,
It is shown in Table 1. Erosion index = (Erosion rate of target sample / Erosion rate of standard sample) × 100 (2) From equation (2), if the erosion index of the target sample is smaller than the erosion index 100 of the standard sample, the durability is high, and if it is large, It was evaluated that the corrosion resistance was low.

[0050]

[Table 1]

Comparative Example 1 A kneaded product and an amorphous refractory were obtained in the same manner as in Example 1 except that 4.0 parts by weight of alumina cement was used instead of 4.0 parts by weight of hydraulic alumina. Evaluation was performed in the same manner as in Example 1. Table 1 shows the results of the amounts of the raw materials and the like, the vibration flow value, and the erosion index.

Comparative Example 2 A kneaded product and an amorphous refractory were obtained in the same manner as in Example 1 except that nickel oxide was not added and the powder of alumina refractory aggregate was 20.4 parts by weight. Evaluation was performed in the same manner as in Example 1. Table 1 shows the results of the amounts of the raw materials and the like, the vibration flow value, and the erosion index.

Examples 2 to 4 and Comparative Examples 3 and 4 As shown in Table 2, kneaded materials and irregular refractories were obtained in the same manner as in Example 1 except that the amounts of the nickel oxide powder and the like were changed. These were evaluated in the same manner as in Example 1. Table 2 shows the results of the amounts of the raw materials and the like, the vibration flow value and the erosion index. In Comparative Example 4, an erosion test was not possible because cracks occurred in the molded body.

[0054]

[Table 2] * 1 Unable to measure because good specimens were not obtained after firing.

Example 5 31.0 parts by weight of coarse particles of refractory SiC (silicon carbide) aggregate having a particle size of more than 1 mm and 3 mm or less, and a particle size of 0.1
27.1 parts by weight of fine particles of SiC refractory aggregate exceeding 5 mm and not more than 1 mm, particle size exceeding 50 μm and 0.15
18.4 parts by weight of a powder of a refractory SiC aggregate having a diameter of 1 mm or less, 2.0 parts by weight of nickel oxide powder having an average particle size of 1 μm,
16.0 parts by weight of ultrafine alumina powder having an average particle size of 2 μm, 1.5 parts by weight of ultrafine silica powder having an average particle size of 0.6 μm, and 4.0 parts by weight of hydraulic alumina having an average particle size of 10 μm. To 0 parts by weight, 0.08 parts by weight of the organic fiber, 0.1 parts by weight of the dispersant, and 6.0 parts by weight of water were added, and the mixture was kneaded with a mixer for 6 minutes. The fluidity of the obtained kneaded material was evaluated as a vibration flow value in the same manner as in Example 1.
Table 3 shows the results of the compounding amount and the vibration flow value. In Table 3,
The amount is expressed in parts by weight. Next, an amorphous refractory was obtained from the kneaded material in the same manner as in Example 1. The corrosion resistance of the obtained refractory was evaluated as an erosion index in the same manner as in Example 1. Table 3 shows the results.

[0056]

[Table 3]

Comparative Example 5 A kneaded product and an amorphous refractory were obtained in the same manner as in Example 5 except that 4.0 parts by weight of alumina cement was used instead of 4.0 parts by weight of hydraulic alumina. Evaluation was performed in the same manner as in Example 1. Table 3 shows the amounts of the raw materials and the like, the results of the vibration flow value and the erosion index.

Comparative Example 6 A kneaded product and an amorphous refractory were obtained in the same manner as in Example 5 except that nickel oxide was not used and the powder of the SiC refractory aggregate was changed to 20.4 parts by weight. Evaluation was performed in the same manner as in Example 1. Table 3 shows the amounts of the raw materials and the like, the results of the vibration flow value and the erosion index.

Example 6 As shown in Table 3, kneaded materials and irregular refractories were obtained in the same manner as in Example 5 except that the amounts of the nickel oxide powder and the like were changed. Was evaluated. Table 3 shows the amounts of the raw materials and the like, the results of the vibration flow value and the erosion index.

Examples 7 to 9 and Comparative Example 7 As shown in Table 4, kneaded materials and amorphous refractories were obtained in the same manner as in Example 1 except that the amounts of the nickel oxide powder and the like were changed. Was evaluated in the same manner as in Example 1. Table 4 and FIG. 5 show the results of the amounts of the raw materials and the like, the vibration flow value, the erosion index, and the average pore diameter. The average pore size was measured by a mercury porosimeter by cutting the obtained amorphous refractory into small pieces.

[0061]

[Table 4]

From Table 1, it can be seen that Example 1 of the alumina-based amorphous refractory material has a smaller erosion index and lower corrosion resistance than Comparative Example 1 using alumina cement or Comparative Example 2 in which no nickel oxide powder was blended. Excellent. Further, from Table 2, when the content of nickel oxide is at least in the range of 0.7 to 18% by weight, the balance between fluidity and corrosion resistance is excellent. Also, from Table 3, Example 5 or 6 of the silicon carbide-based amorphous refractory has a smaller erosion index than Comparative Example 5 using alumina cement or Comparative Example 6 in which no nickel oxide powder was blended, Excellent corrosion resistance.

As can be seen from Table 4 and FIG. 5, Examples 7 to 9 of the alumina-based amorphous refractory material have a smaller average pore diameter and a lower erosion index than Comparative Example 7 and have excellent corrosion resistance, and also have an excellent balance between fluidity and corrosion resistance. You can see that. Table 4 and FIG.
From the above, it can be seen that, by mixing the nickel oxide fine powder with the alumina-based refractory aggregate and the alumina fine powder, the average pore diameter becomes smaller and the corrosion resistance becomes higher accordingly.
The relationship between the average pore diameter and the corrosion resistance in FIG. 5 is that the voids in the obtained alumina-based amorphous refractory are filled by the generated spinel-type alumina-nickel oxide compound, thereby suppressing immersion of the slag. It can be said that it suggests.

[0064]

According to the present invention, a kneaded material having excellent fluidity can be obtained at a low cost by adding predetermined kneading water to the amorphous refractory raw material according to the present invention, and the amorphous refractory obtained by firing the kneaded material is obtained. The material has excellent corrosion resistance. That is, it is possible to manufacture an inexpensive amorphous refractory having excellent corrosion resistance at a low cost with excellent workability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a sample shape in an erosion test.

FIG. 2 is a schematic diagram showing an erosion test.

FIG. 3 is a schematic diagram showing a method for evaluating an erosion rate.

FIG. 4 is a schematic view showing a method for evaluating an erosion rate.

FIG. 5 is a graph showing the relationship between the amount of nickel oxide added, the erosion index, and the average pore diameter.

[Explanation of symbols]

 A Amorphous refractory sample B Hexagonal column-shaped specimen C Rotating device D Recess E Slag F Erosion

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tohru Yamagishi 1-8-1 Shintoda, Hamamatsu-shi, Shizuoka Nichias Inside Hamamatsu Laboratory Co., Ltd. (72) Inventor Hiroki Ishizuka 1-81-1, Shintoda, Hamamatsu-shi, Shizuoka Nichias Inside the Hamamatsu Laboratory Co., Ltd. (72) Inventor Junichi Irimura 1-81-1, Shintoda, Hamamatsu-shi, Shizuoka Nichias Inside the Hamamatsu Research Laboratories Co., Ltd. (72) Inventor Junichi Sano 1-7-89 Minami Kohoku, Suminoe-ku, Osaka-shi, Osaka Hitachi Zosen Corporation (72) Yoshimasa Miura 1-7-89 Minami Kohoku, Suminoe-ku, Osaka, Osaka Prefecture Hitachi Zosen Corporation (72) Hideo Shimotani 1-7 Minami Kohoku, Suminoe-ku, Osaka, Osaka No. 89 Hitachi Zosen Corporation F term (reference) 4G033 AA02 AA24 AB02 AB04 AB09 BA01 4K051 AA00 BB03

Claims (15)

[Claims] 1. A refractory raw material comprising a refractory aggregate, a ceramic fine powder, a nickel oxide powder or a nickel powder, and a hydraulic binder. 2. The refractory raw material according to claim 1, wherein the ceramic fine powder contains alumina fine powder. 3. The alumina fine powder is 8 to 27% by weight, the nickel oxide powder or the nickel powder is 0.7 to 18% by weight in terms of NiO, and the hydraulic binder is 2 to 1%.
The amorphous refractory raw material according to claim 2, comprising 0% by weight. 4. The raw material according to claim 1, wherein the ceramic fine powder contains alumina fine powder and the refractory aggregate contains alumina refractory aggregate. 5. The alumina fine powder is 8 to 27% by weight, the alumina refractory aggregate is 48 to 80% by weight, and the nickel oxide powder or the nickel powder is 0.1 to 0.2% in terms of NiO.
7 to 18% by weight and 2 to 10% by weight of the hydraulic binder
The raw material for refractory according to claim 4, wherein the raw material comprises: 6. The alumina-based refractory aggregate or the alumina-based fine powder comprises one or more selected from high-purity alumina, alumina silica, mullite, bauxite, and chamotte. 6. The amorphous refractory raw material according to any one of 2 to 5. 7. The refractory raw material according to claim 1, wherein the refractory aggregate includes a silicon carbide refractory aggregate. 8. The refractory aggregate is 48 to 80% by weight, the ceramic fine powder is 12 to 27% by weight, and the nickel oxide powder or nickel powder is 0.7 to 18 in terms of NiO.
The amorphous refractory raw material according to any one of claims 1 to 7, comprising 2 to 10% by weight of the hydraulic binder. 9. The ceramic fine powder having an average particle size of 0.1 to 50 μm.
The refractory raw material according to any one of the above. 10. The refractory raw material according to claim 1, wherein the ceramic fine powder comprises an alumina fine powder and a silica fine powder. 11. The compounding amount of the alumina fine powder is 8 to 10.
26.5% by weight, the compounding amount of the silica fine powder is 0.5 to
The raw material for refractory according to claim 10, wherein the content is 10% by weight. 12. The amorphous refractory raw material according to claim 1, wherein the nickel oxide powder or the nickel powder has an average particle size of 0.1 to 100 μm. 13. The amorphous refractory raw material according to claim 1, wherein the hydraulic binder is hydraulic alumina. 14. An amorphous refractory obtained by adding water to the amorphous refractory raw material according to any one of claims 1 to 13 to form a kneaded product, and further firing the kneaded material. 15. The refractory according to claim 14, wherein the refractory comprises a spinel type alumina-nickel oxide compound.