JPH10182246A - Bond castable composition of non-slumping magnesia-silica and its working method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-slumping, high density and low water content castable composition improved in corrosion resistance and mechanical strength at a high temp. such as hot strength and necessitating substantially not or much cement as a binder. SOLUTION: This non-slumping castable composition is composed of a 1st pump transportable component, which is prepared by kneading 100wt.% solid portion consisting of 0.5-30wt.% magnesia fine powder, 0.5-10wt.% siliceous fine powder, 0.01-0.5wt.% deflocculant and the balance refractory aggregate and fine powder with water in a quantity enough to attain the consistency capable of pump transportation, and a 2nd component of a coagurant, which is added into the 1st component at the time of working. Further a calcium aluminate cement in a quantity of <=2wt.% per 100wt.% solid portion of the 1st component in the content of calcia component contained in the calcium aluminate cement and/or <=5wt.% clay are added into 100wt.% solid portion of the 1st component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel non-slump castable composition for use in a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator and the like.
The present invention relates to a method for applying the castable composition without using a mold or a formwork.

[0002]

2. Description of the Prior Art Portland cement-based wet spray compositions and methods of applying them are old and well known. For example, a mixture containing sand, gravel and Portland cement is made, kneaded with water to a pumpable consistency, and then the concrete is pumped into a nozzle. In this nozzle, a cement hardening accelerator and air are added, and the concrete material is sprayed on the surface, for example, the wall surface of the object to be sprayed. At that surface, the concrete hardens quickly enough to prevent slumping from the sprayed surface. Such hardening is a result of the chemical accelerator accelerating with the Portland cement to initiate the hardening action quickly, whereby the viscosity of the concrete rapidly rises to a level high enough to prevent slumping. To rise.

However, while this is suitable for applications such as civil engineering, refractory concrete is not used satisfactorily with Portland cement as a binder. This is because Portland cement cannot withstand the high temperatures and corrosive environments in which refractory materials are placed. Thus, the majority of refractory concrete, known as refractory castables, contains calcium aluminate cement rather than Portland cement. Calcium aluminate cements have much higher fire resistance and also have higher corrosion resistance to the environments found in high temperature refractory applications.

A castable composition for wet spraying using such a calcium aluminate cement as a binder and a method of applying the same are disclosed in JP-A-54-6100.
No. 5 is known. However, the composition disclosed in Japanese Patent Application Laid-Open No. 54-61005 contains calcium aluminate cement as much as 20% by weight, and the amount of water added is 10 to 20% by weight.
Therefore, the composition is inferior in corrosion resistance as a refractory material and mechanical properties at high temperatures.

Therefore, U.S. Pat. S. Patent 55497
At 45, a castable composition of a non-slump, low moisture, low calcium aluminate cement is shown.

[0006]

Problems to be Solved by the Invention S. Patent
The castable composition of the non-slump, low moisture, low calcium aluminate cement shown in US Pat.
Although it can provide sufficient corrosion resistance and mechanical properties as a commonly used refractory material, calcia contained in cement forms a low melt with acidic or neutral refractory material,
Further, in order to improve mechanical properties at high temperatures such as corrosion resistance and hot strength, it is sometimes desirable to reduce the addition amount of the calcia component, that is, the cement, to the limit.

An object of the present invention is to basically eliminate the need or a large amount of cement as a binder in order to further improve mechanical properties at high temperatures such as corrosion resistance and hot strength. An object of the present invention is to provide a castable composition having a slump property, a high density, and a low moisture content, and a method for applying the same.

[0008]

According to the present invention, there is provided a method for manufacturing a semiconductor device comprising:
100% by weight of solids consisting of magnesia fine powder of 0.5% by weight, silicic fine particles of 0.5 to 10% by weight, deflocculant of 0.01 to 0.5% by weight, and refractory aggregate and fine powder To
A non-slump property comprising a pumpable first component kneaded with an amount of water sufficient to achieve a pumpable consistency and a second component coagulant added to the first component during construction. The castable composition, and the calcium aluminate cement in an amount such that the calcia component contained in the calcium aluminate cement is 2% by weight or less based on 100% by weight of the solid content of the first component, and / or 5% by weight or less Is achieved by adding a non-slump castable composition to a solid content of 100% by weight of the first component, and a method of applying the castable composition.

[0009]

DETAILED DESCRIPTION OF THE INVENTION The first component of the castable composition of the present invention comprises a refractory aggregate and fines, magnesia fines, siliceous fines, a deflocculant to achieve a pumpable consistency. Kneaded with a sufficient amount of water. Further, the first component may include one or both of a calcium aluminate cement and a clay for the purpose of enhancing non-slump properties during construction.

The refractory aggregate and fine powder (except for magnesia fine powder) include a molten metal container, a molten metal processing apparatus,
Any suitable refractory material for cement kilns, incinerators, etc. may be used, for example, electrofused or sintered alumina, calcined alumina, bauxite, electrofused or synthetic mullite, sillimanite, andalusite, kyanite , Ban earth shale, chamotte, olivine, quartzite, fused silica, electrofused or sintered magnesia, electrofused or sintered spinel,
Fused or sintered zirconia, zircon, chromite, fused or sintered magnesia-lime, fused zirconia-mullite, fused alumina-zirconia, titania, silicon carbide,
Examples thereof include silicon nitride, natural or artificial graphite, petroleum coke, pitch coke, anthracite, carbon black, and amorphous carbon such as pitch. One or more of these are used.

In the case of a castable composition containing a carbon component such as graphite or amorphous carbon, aluminum, an aluminum-silicon alloy, an aluminum-magnesium alloy, silicon, magnesium or the like is used for the purpose of preventing carbon oxidation and improving strength. Metal powder, carbides such as silicon carbide and boron carbide, borides such as zirconium boride, and glass components such as borosilicate glass can also be used.

The fine powder referred to in the present invention has a particle size of 0.2 mm.
Or less, and 50% by weight or more thereof is substantially 74 μm.
m means the above raw material.

As the magnesia fine powder, one or more kinds of powders called electrofused or sintered magnesia, or an active mug obtained by firing magnesium hydroxide or magnesium carbonate at 400 to 1000 ° C. are used. As the sintered magnesia, dust collected in a magnesia firing kiln usually called cyclone powder can also be used.

Examples of the siliceous fine particles include those called evaporated (volatile) silica which is generated as a by-product during the production of silicon or ferrosilicon, white carbon, anhydrous or hydrous amorphous silicic acid, shirasu, and silica sol.
Use two or more species.

[0015] The siliceous fine particles also function as a fluidity aid for imparting fluidity to the first component. Of course, among the refractory fine powders described above, fine powders such as calcined alumina, titania, and carbon black having a particle size of 10 μm or less also have a function as a flow aid.

The magnesia fine powder and the siliceous fine particles exhibit hydraulic properties as a magnesia-silica-water bonding part in the castable composition, and further dehydrate at high temperatures,
A magnesia-silica or magnesia-silica-containing ceramic bond is formed. Accordingly, it is desirable that the particle size of the magnesia fine powder is 75 μm or less, and the particle size of the siliceous fine particles is 10 μm or less. It is 75
In the case of magnesia larger than μm, and silicic acid fine particles larger than 10 μm, the magnesia-silica-water bonding portion is not sufficiently formed at a high temperature because a magnesia-silica or magnesia-silica-containing ceramic bond is not sufficiently formed. This is because

As the deflocculant, one or more of condensed phosphoric acid, polyacrylic acid, polycarboxylic acid, phosphonic acid, humic acid, alkylsulfonic acid, aromatic sulfonic acid and the like, or salts thereof are used. .

As the calcium aluminate cement,
Any of the commonly used refractory amorphous compositions can be used for the present invention. For example, a calcia content of 15 to 22% by weight corresponding to the first type of JIS, and a calcia content of 25 to 3 corresponding to the second type of JIS
0% by weight, 30 to 40% by weight of calcia content corresponding to the third or fourth type of JIS, and
One or more of other calcium aluminate cements are used.

As the clay, one or two or more of kaolin group clay represented by ball clay, montmorillonite group clay represented by bentonite, and illite group clay are used.

The calcium aluminate cement and clay are
It can be added for the purpose of improving non-slump properties during construction. However, as the amount of calcium aluminate cement used increases, the amount of low melt produced at high temperatures increases,
When high mechanical properties at high temperatures such as high corrosion resistance and hot strength are desired, the amount used is limited.

The clay also functions as a plasticizer that imparts plasticity to the first component. Of course, organic plasticizers commonly used in refractory amorphous compositions can also be used for the purpose of imparting plasticity.

Further, the first component of the present invention is a steel fiber added for the purpose of reducing spalling in a general refractory amorphous composition, and an organic fiber added for the purpose of preventing explosion during drying. And metallic aluminum can be used in the usual customary amounts.

The additive water is added in as small an amount as possible to obtain a first component having a pumpable consistency suitable for use with the swing valve pump and the spray nozzle used therewith. To be done.

The kneaded first component needs to maintain a pumpable consistency until the coagulant of the second component is added at the spray nozzle portion. The pot life, which is the time for maintaining the tension, can be adjusted by the specific surface area and the addition amount of the magnesia fine powder and the siliceous fine particles. That is, when the specific surface area of the magnesia fine powder is reduced or the added amount is reduced, or when the specific surface area of the siliceous fine particles is increased or the added amount is increased, the pot life becomes longer.

If the required pot life cannot be ensured due to problems in temperature and material design, hexafluorosilicic acid, oxycarboxylic acid, condensed phosphoric acid,
Aggregation can be achieved by using additives such as polyacrylic acid or their salts that have the effect of retarding coagulation and hardening, or by using magnesia fine powder surface-treated with a silane coupling agent or the like for part or all of magnesia fine powder. It is also possible to extend the pot life by slowing down the rate and cure rate, i.e. the rate of formation of the magnesia-silica-water bond.

The flocculant of the second component acts to "overwhelm", ie, extinguish, the effect of the deflocculant introduced into the first component and immediately convert the first component into a viscous plastic; Ultimately, the castable composition imparts sufficient tackiness and rigidity to adhere to the wall without slumping. That is, the coagulant causes the first component to coagulate and promotes hydraulic hardening by forming a magnesia-silica-water-based bonding portion.

Examples of the coagulant having such an action include aluminates such as sodium aluminate, carbonates such as sodium carbonate, alkali silicates such as sodium silicate, chlorides such as calcium chloride, sodium hydroxide and hydroxide. There are aqueous solutions, suspensions and powders of hydroxides such as calcium, calcium aluminate, Portland cement and the like, and one or more of these are used.

100% by weight of the solid content of the first component is 0.5%
-30% by weight of magnesia fine powder, 0.5 to 10% by weight of siliceous fine particles, 0.01 to 0.5% by weight of a deflocculant, and the balance of refractory aggregate and fine powder. Further, in order to enhance the non-slump property at the time of construction, the amount of the calcium aluminate cement contained in the calcium aluminate cement is within 2% by weight based on 100% by weight of the solid content of the first component. One or both of the clays, by weight or less, are added to 100% by weight solids of the first component.

The amount of the magnesia powder used is 0.5 to 30.
% By weight. 0.5% by weight of magnesia powder
The reason is that even if active magnesia having a very small particle size and high activity is used, if the amount used is less than 0.5% by weight, the bonding portion is not sufficiently formed, so that the adhesion is poor, and This is because the strength becomes low. The reason for limiting the content to 30% by weight or less is that if the content exceeds 30% by weight, a particle size composition suitable as the first component having a low water content cannot be obtained, and it is difficult to perform pumping at a low water content.

The amount of the siliceous fine particles used is 0.5 to 10% by weight. The reason why the amount of the siliceous fine particles is limited to 0.5% by weight or more is that if the amount is less than 0.5% by weight, the bonding portion is not sufficiently formed as described above, resulting in low strength. Yes, the limit of 10% by weight or less is 1
If the content exceeds 0% by weight, the effect of improving mechanical properties at high temperatures such as corrosion resistance and hot strength decreases.

The amount of the peptizer used is 0.01 to 0.5% by weight. The use amount of the deflocculant is limited to 0.01% by weight or more because the effect as a deflocculant is not exhibited when the use amount is less than 0.01% by weight. Is not obtained. 0.5% by weight
When the amount exceeds 0.5% by weight, the coagulant effect of the second component, ie, the coagulant, is reduced, so that the adhesion of the castable composition is reduced and the peptizing property of the first component is reduced. The pump pressure can not be pumped with low moisture,
This is because mechanical properties such as strength may be reduced, or corrosion resistance may be reduced.

The amount of water to be added depends on the specific gravity and the particle size of the first component, but usually the first component which can be easily pumped with a water content of 5.0 to 8.0% by weight is obtained.
However, when the first component is pumped to a very long distance and to a high place, the water content may be increased by about 1 to 3% by weight, and the porosity of the material may be intentionally increased like a heat insulating material. Is increased, the amount of water to be added may be further increased.

When it is necessary to increase the construction thickness, the amount of the calcia component contained in the calcium aluminate cement is 2% by weight in the solid content of the first component of 100% by weight in order to enhance the non-slump property during the construction. % Or less of calcium aluminate and / or 5% by weight of clay is added to 100% by weight of the solids of the first component.
The reason for limiting the amount of calcium aluminate cement to 2% by weight or less based on the amount of calcia component contained in the calcium aluminate cement in 100% by weight of the solid content of the first component, and to limit the amount of clay to 5% by weight is as follows. The reason for this is that if the amount of these materials used increases, the amount of low melt produced at high temperatures increases, and the effect of improving mechanical properties at high temperatures such as corrosion resistance and hot strength decreases. When using 3% by weight or more of clay,
The amount of the calcium aluminate cement used is desirably 1.5% by weight or less of the calcia component contained in the calcium aluminate cement in 100% by weight of the solid content of the first component.

The amount of the coagulant, the second component added immediately before spraying, is important because it can adversely affect the desired porosity (apparent porosity) of the castable composition. Porosity is considered to be the most important physical property in castable compositions because all other properties, such as strength and corrosion resistance, are directly proportional to the porosity of any castable composition. Generally, when the porosity increases, both the corrosion resistance and the strength decrease, so that it is desirable that the porosity be as small as possible.
Therefore, the amount of the coagulant added is such that the castable composition cures at a sufficient speed, and the porosity after dehydration as a high-density castable composition is 25% or less, preferably 20% or less.
%. Usually, the above condition is satisfied with an addition amount in the range of 0.2 to 3% by weight based on 100% by weight of the solid content of the first component. 0.2 added
If the amount is less than the percentage by weight, it is difficult to uniformly mix the first component with the nozzle component. If the content is more than 3% by weight, the curing rate of the castable composition becomes too high, so that the porosity of the construction body becomes large. If the coagulant is an aqueous solution or a suspension, the water content of the entire castable composition is increased. This is not preferable because the porosity of the construction body may increase due to the increase in the porosity.

However, when the porosity of the material is intentionally increased as in the case of a heat insulating material, the amount of the coagulant as the second component can be increased. That is, in the case of a castable composition in which heat insulation is more desirable than corrosion resistance and strength, the porosity may be set to be larger than 25%.

The swing valve pump used in the present invention is a very efficient means of material transfer, and the present invention therefore provides the first component having a much smaller amount of water than the conventional one over a long distance and It can be transported to high places. The swing valve pump is usually connected to the nozzle device via steel pipes and / or hoses. Such a nozzle arrangement has an air line line from which air is supplied to the nozzle for blowing a pumpable first component onto the surface to be lined with the refractory material.

A further aspect of the present invention is that when the first component is about to be sprayed onto the surface of a refractory container or apparatus, the second component coagulant is applied, preferably via the air line described above. That is to add to the nozzle.

The device for supplying the second component flocculant to the nozzle should have a capacity to balance the given material output of the swing valve pump and the air pressure in the air line (Usually about 3.52 to 7.03 kg / c
m ² = should be capable of generating sufficient pressure to about 50～100Psi) above.

[0039]

EXAMPLES Examples according to the present invention are shown in Tables 1, 2 and 4.
Table 3 shows a comparative example.

The application of the embodiment of the first component specified in the present invention is as follows. Aggregate and fine powder of refractory raw material, magnesia fine powder, siliceous fine particles, deflocculant, calcium aluminate cement and clay are shown below. used. That is, as the aggregate and fine powder of the refractory raw material, 99.5% pure fused alumina, 98.6% pure fused magnesia, 99.7% pure
A sintered alumina having a purity of 99.3%, a sintered magnesia having a purity of 95.4%, a calcined alumina having a purity of 99.6% and an average particle size of 1.5 μm, a silicon carbide having a purity of 93.7%, A pitch having a fixed carbon amount of 60.0% was used. As magnesia fine powder, a sintered magnesia having a purity of 98.1% was pulverized and passed through a 75 μm sieve (average particle diameter of 20.%).
4 μm) or 99.9% purity, 1.5 μm average particle size
m (BET specific surface area: 20 m ² / g) was used. Evaporated silica having a purity of 96.0% and an average particle diameter of 0.28 μm was used as the siliceous fine particles. As the peptizer, sodium polyacrylate and sodium ligninsulfonate were used. "SECAR71" manufactured by Lafarge Co., Ltd. was used as the calcium aluminate cement, and ball clay was used as the clay. It should be noted that what is shown here is not limited to the examples, and the same effects can be obtained as long as they are described in the embodiments of the present invention. Here, all the average particle diameters of the fine powder are values measured by a laser diffraction method.

Examples of the coagulant as the second component defined in the present invention include 9.0% by weight of K ₂ O and 20.
Although an aqueous solution of potassium silicate composed of 6% by weight of SiO ₂ was used, it goes without saying that the same effect can be obtained as long as it is described in the embodiment of the present invention.

In the table, the amounts of water and coagulant added are indicated by the outer value (+) with respect to 100% by weight of the solid content of the first component.

In the spraying operation, the first components listed in the table were kneaded with a mixer, and Allentown was used.
0.05mm inside diameter using AP-10 swing valve pump
A 1-meter (2 inch), 30.48-m (100 ft) heavy-duty hose is pressure-fed and further sprayed at the spray nozzle connected to the tip at 5.62 kg / cm.
² (80 psi), 8.5 m ³ / min (300 cft) of compressed air is added together with the coagulant of the second component and a vertically installed 9.29 m ² (100 ft ² ) area of chamotte brick is sprayed onto the surface. The method was performed. Here, a 35.15 kg / cm ² (500 psi) diaphragm chemical pump was used for transferring the flocculant.

The items of pumping performance shown in the table were very good when the pump pressure was 140.6 kg / cm ² (2000 psi) or less under the above conditions. The product was marked with “◎” and the pump cylinder pressure was 140.6 kg / cm ² (200
0 psi) is marked with “○” for those that could be pumped, and “x” for those that could not be pumped.

The items of the adhesion rate shown in the table are "◎" when the ratio of the adhesion weight to the total construction weight was very good at 95% or more under the above-mentioned conditions.
A mark, “○” indicates that the sample was good at 90% or more and less than 95%, and “X” indicates a sample that was poor, at less than 90%.

The items of the apparent porosity shown in the table are as follows.
When the apparent porosity measured after baking for 3 hours was 20% or less, a mark “◎” was given. When the apparent porosity was greater than 20% and 25% or less, a mark “○” was given. Is marked with “x”.

The items of the hot bending strength shown in the table are the cross section □ 40 mm cut out of the construction body constructed under the above conditions,
Using a 160 mm long test piece in an electric furnace at 1500 ° C,
The three-point bending strength of a span of 100 mm was measured, and the hot bending strength was 200% or more of the hot bending strength of Comparative Example 1 (an example using calcium aluminate cement as a binder), and was extremely large. Is "◎" mark, 150% or more 2
If the hot strength is as high as less than 00%, mark "O", 15
If it is less than 0%, the improvement of hot strength is insufficient, and the mark "x" is entered.

In the corrosion resistance items shown in the table, a test piece was cut out from a construction body constructed under the above conditions, and a slag rotation tasting test was performed using CaO / SiO ₂ (molar ratio) = 1.2 slag. The test was performed at 1600 ° C., and the erosion rate was 60% or less of the erosion rate of Comparative Example 1 and marked with “耐” when the corrosion resistance was very good, and the erosion rate was greater than 60% and 90% or less when the corrosion resistance was good Is marked with a “○”, and those with a corrosion resistance greater than 90% and insufficiently improved are marked with a “x”.

Examples 1 to 27 shown in Tables 1, 2 and 4
Is a result of the construction body which satisfies the conditions specified by the present invention, and a good construction body which basically does not require cement as a binder or does not require a large amount was able to be obtained.

[Table 1]

[Table 2]

[Table 4]

Table 3 shows Comparative Examples 1 to 10.

[Table 3]

Comparative Example 1 shows a conventional composition using 7% by weight of calcium aluminate cement. Because of the large amount of calcium aluminate cement, the corrosion resistance and hot strength were inferior to those of the examples of the present invention.

In Comparative Example 2, the amount of magnesia fine powder used was 0.3% by weight or less (Examples 1, 2, 3, 4 and 5 in which the amount of magnesia fine powder was changed in the range of 0.5 to 30% by weight). Therefore, the adhesion rate was not satisfactory.

In Comparative Example 3, the amount of the magnesia fine powder used was more than the specified range of the present invention (Examples 1, 2, 3, 4 and 5 in which the amount was varied from 0.5 to 30% by weight) (35% by weight). However, pumping could not be performed with low moisture.

In Comparative Example 4, the amount of the siliceous fine particles used was less than the specified range (0.5 to 10% by weight of Examples 6, 7 and 8) (0.3% by weight). The adhesion rate was not satisfactory.

In Comparative Example 5, since the amount of the siliceous fine particles used was larger than the specified range of the present invention (Examples 6, 7, and 8 varied from 0.5 to 10% by weight) (12% by weight), the corrosion resistance was high. And the improvement in hot strength was small.

In Comparative Example 6, the amount of the peptizer used was changed in the range specified in the present invention (0.01 to 0.5% by weight).
9 and 10) Due to the following (0.005% by weight), pumping could not be performed with low moisture.

In Comparative Example 7, the amount of the deflocculant was changed in the range specified in the present invention (0.01 to 0.5% by weight).
9 and 10), the adhesion was poor and the improvement in corrosion resistance was small.

In Comparative Example 8, the amount of calcium aluminate cement (SECAR71) used was within the specified range of the present invention (first type).
The amount of the calcia component contained in the calcium aluminate cement based on 100% by weight of the solid content of the component was greater than that in Examples 2, 11, 12, 13, 17, and 18) in which the amount of the calcia component was changed within 2% by weight. The amount of calcia component contained in the calcium aluminate cement was 2.4% by weight based on 100% by weight of the solid content, so that the adhesion was very good, but the improvement in corrosion resistance and hot strength was small. there were.

In Comparative Example 9, the amount of clay (ball clay) used was larger than the specified range of the present invention (Examples 2, 14, 15, 16, 17 and 18 changed within 5% by weight) (7% by weight). ), The adhesion was very good, but the improvement in corrosion resistance was small.

In Comparative Example 10, the apparent porosity after dehydration was large because the amount of the coagulant as the second component was too large.
The corrosion resistance was inferior to the examples of the present invention.

Importantly, the castable composition of the present invention does not require a formwork to hold it in place before it cures sufficiently to produce no slump.
Can be applied, which of course saves the labor and time of installing and removing such forms.

[0066]

According to the present invention, there is provided a non-slump which does not require or basically does not require cement as a binder for use in a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator and the like. Provided is a castable composition having a high density, a high density and a low moisture content, and a construction method capable of constructing the castable composition without providing a mold or a formwork.

As a result, it is possible to improve mechanical properties at high temperatures such as corrosion resistance and hot strength, and to save labor and time for installing and removing the formwork and labor.

Claims (4)

[Claims] 1. A magnesia fine powder of 0.5 to 30% by weight,
0.5 to 10% by weight of siliceous fine particles, 0.01 to 0.5%
A first component obtained by kneading water with 100% by weight of a deflocculant and 100% by weight of a solid content composed of refractory aggregate and fine powder, and pumping the first component mixed with water. A non-slump magnesia-silica system comprising the pumpable first component present in an amount sufficient to achieve a possible consistency and a second component coagulant added to the first component during construction. Bond castable composition. 2. The amount of the calcia component contained in the calcium aluminate cement is 100% by weight of the solid content of the first component.
The composition according to claim 1, wherein the amount of the calcium aluminate cement is at most 2% by weight, and / or the clay is at most 5% by weight in the solids content of the first component of 100% by weight. 3. A method of spraying a castable composition using a swing valve pump and an auxiliary spray nozzle without using a mold and a mold, comprising: 0.5 to 30% by weight of magnesia fine powder; 0.5 to 10% by weight of siliceous fine particles,
Pumping and spraying of 0.01 to 0.5% by weight of a deflocculant and 100% by weight of a solid content consisting of refractory aggregate and fine powder through the swing valve pump and the spray nozzle. Making a pumpable first component kneaded with an amount of water sufficient to achieve a possible consistency;
A spraying construction method in which a coagulant of a second component is added to a first component in a spray nozzle immediately before spraying of the component. 4. The amount of the calcia component contained in the calcium aluminate cement is 100% by weight of the solid content of the first component.
The construction method according to claim 3, wherein calcium aluminate cement in an amount of 2% by weight or less and / or clay of 5% by weight or less is contained in 100% by weight of the solid content of the first component.