JP2002213880A - Pneumatic conveying spraying method for irregular refractories - Google Patents

Abstract

(57) [Abstract] (Modifications required) [Problem] To solve the difficulties of the dry spraying method and the wet spraying method, eliminate the need for kneading materials, do not obstruct the transfer pipe, and perform long-distance transfer. Providing a new spray construction method that can be constructed and the construction refractories are of high quality. An amorphous refractory composition 2 containing a refractory aggregate, a refractory powder, a binder and a dispersant is sent in a powder stream into a transport pipe 3 in a powder stream, and is transported while floating in the transport pipe. Then, the construction water is added 4 in the middle of the conveying pipe, and thereafter the air is also conveyed by air flow, and then the one added with the quick setting agent 5 is sprayed through the spray nozzle 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention eliminates the disadvantages of the conventional dry spraying method and wet spraying method, eliminates the need for a kneading operation of the spraying material, and does not cause any blockage in the conveying pipe. The present invention relates to a new method of applying a sprayed amorphous refractory having a high quality, which enables a long-distance transport construction and which has a high quality.

[0002]

2. Description of the Related Art A spraying construction method is known as a promising construction method for irregular-shaped refractories. Compared to the casting method, this construction method does not require a casting formwork and can be easily applied to places where the shape is complicated and the frame is difficult, so it is widely used in more and more fields in recent years. ing. Broadly classified as such spraying construction methods, there are dry spraying method of pneumatic pumping method and wet spraying method of pumping method.
Each has the following advantages and disadvantages.

[0003] The dry spraying method is a powdery spraying method containing a hardening agent such as alumina cement which hardens when combined with water and a refractory powder such as clay for improving the adhesion at the time of spraying. The refractory material is supplied to a pneumatic spraying machine, and the inside of the transfer pipe is pneumatically fed. The construction water is added to the pumped powdered refractory material for spraying at the spray nozzle portion, and the powdered refractory material for spraying is converted into a highly viscous adhesive state containing the construction water in the nozzle. This is a construction method that blows out through a nozzle, adheres to a furnace wall construction part, cures, and constructs a refractory furnace wall.

In this dry spraying method, the refractory material for spraying is pneumatically fed in a powder form, so that the transfer pipe is not clogged, so that the transfer is easy and the transfer can be performed over a long distance. For this reason, it is possible to construct a distant place or a high place with the spraying machine or the spraying refractory material installed on the ground.

[0005] On the other hand, in the dry spraying method, powdery spraying refractory and construction water are mixed in a nozzle to form a viscous spraying refractory. Contact time is short. As a result, the quality of the applied refractory furnace wall becomes uneven because the construction water is not sufficiently mixed with the powdered refractory for spraying, and a stable high-quality refractory with high strength is obtained. Tends to be difficult.

On the other hand, the wet spraying method has been developed in order to obtain a furnace wall having a more uniform quality and excellent physical properties than the refractory obtained by the dry spraying method. It is. In the wet spraying method, a kneaded material called "kneaded clay" is prepared by sufficiently kneading a spraying refractory material and construction water in advance. This clay has a fluidity flow value (using JIS cone) of 20 which can be pumped using a mixer.
The mixture is kneaded until it is about 0 mm, and the mixture is supplied to a pressure pump to be conveyed in a conveying pipe. Then, by adding a quick setting agent for agglomerating the kneaded clay at the nozzle portion and supplying compressed air, it is sprayed on the furnace wall construction portion to relatively instantaneously aggregate and refractory material such as the furnace wall. To construct.

In such a wet spraying method, when the spraying material is supplied to the pressure feed pump as described above,
Since it is necessary to knead the spraying material using a mixer until sufficient fluidity is obtained, a large mixer and a large number of personnel are required. In addition, it is difficult to control the amount of kneading water to obtain an appropriate fluidity by pumping with a pump. For example, if the fluidity is low, blockage occurs in the pump or in the transport pipe. If kneading water is added too much to increase the fluidity, the fine refractory aggregate and the fine refractory powder contained in the refractory for spraying are separated, and the material cannot be transported. As described above, the wet spraying method has many unstable factors at the time of construction on site.

Further, in order to carry the kneaded kneaded clay over a long distance by pumping, a large pump is required because the viscosity of the kneaded clay is large, and the carrying distance is also shorter than in the dry spraying method. It is short and at most about 100 meters in horizontal distance. Furthermore, in the wet spraying method using a pump, at the time of completion of the work, since the kneaded clay remains in the transfer pipe, there is also a problem that a large amount of material is lost and it takes a lot of people and time to clean the material. .

Further, conventionally, as described in JP 62-36071 Patent Publication No. <br/> paper, against powdery spraying refractory composition, the final construction water content required 1 / 5/3/4 of the water, kneaded the mixture with the refractory composition in advance by a mixer, and pressurized to a dry spray gun. A construction method is known in which an amorphous refractory is constructed by spraying a solution containing a solution comprising a curing accelerator and a curing accelerator.

However, in this construction method, similarly to the conventional dry spray construction method, an aqueous solution containing a mixture of construction water and a hardening accelerator is finally applied to the spraying refractory material at the spray nozzle. Because of the addition, the required amount of moisture is uniformly sprayed for a short period of time in contact with the refractory material and is not sufficiently dispersed, so that a high-quality uniform furnace wall cannot be constructed. Does not limit the scope of the dry spraying method, and cannot be said to be a method that improves the difficulties of the dry spraying method.

[0011]

SUMMARY OF THE INVENTION The present invention eliminates the disadvantages of the conventional dry spraying method and wet spraying method as described above, eliminates the necessity of kneading the spraying material, and reduces A new air-flow-conveying spraying method for irregularly shaped refractories, which enables long-distance transport construction without blockage in the building, and that the constructed refractory has high quality and uniform characteristics provide.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a novel idea obtained by sufficiently analyzing the characteristics of each of a dry spraying method and a wet spraying method. This is based on knowledge. That is,
Amorphous refractories having the same level of excellent properties as the wet spraying method do not necessarily use a kneaded clay obtained by sufficiently kneading, but a powdery amorphous refractory composition (hereinafter, referred to as It has been found that it can be easily obtained by carrying using a refractory composition) and adding the entire amount of construction water in the middle of the carrying pipe. This is because even if the entire amount of construction water is added in the middle of the conveying pipe, if the addition is not in the vicinity of the spray nozzle, a more than expected mixing of the refractory composition and the construction water is performed. I think that the.

Here, when the entire amount of water required for the construction is added to the powdery refractory composition conveyed in the conveying pipe, the viscosity increases and adheres to the inside of the conveying pipe, which is blocked. It is expected to do. However, in the present invention, as a powdery refractory composition to be transported in the transport pipe,
It has been found that the use of an amorphous refractory composition containing a dispersant in addition to a refractory aggregate, a refractory powder, and a binder can prevent such a clogging of a transport pipe. Thus, the present invention has succeeded in developing a new construction method that solves the above-mentioned problems, that is, the difficulties of the dry spraying method and the wet spraying method.

The present invention has the following main configuration. (1) An amorphous refractory composition containing a refractory aggregate, a refractory powder, a binder and a dispersant is sent in a powder stream into a transport pipe in a gas stream, and is transported while floating in the transport pipe. In the middle of the construction water, and then transported by air flow,
Then, a blowing agent is added to the tip of the spray nozzle at the upstream of the spray nozzle and sprayed through the spray nozzle. (2) The refractory powder is a refractory ultrafine powder having an average particle diameter of 10 μm or less, the binder is alumina cement, and the dispersant is a condensed phosphate, carboxylate or sulfonate. The method of spraying an irregular-shaped refractory according to the above (1). (3) The construction water is 1 to 50 m from the addition position of the quick setting agent.
(1) or (2), wherein the irregular-shaped refractory is blown by an air-flow-conveying method. (4) The quick-setting agent is supplied from the tip of the spray nozzle in an amount of 0.3 to 0.3.
The method of the above-mentioned (1), (2) or (3), wherein the amorphous refractory is added upstream at a distance of 2.5 m. (5) After adding the construction water, a means for uniformly mixing the construction water and the refractory composition is provided, and the mixture is further uniformly mixed. Air-flow type spraying method for refractories. (6) A fire-resistant wall constructed by the airflow-conveying spraying method of the irregular-shaped refractory according to any one of the above (1) to (5). Hereinafter, the present invention will be described in more detail.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The powdery amorphous refractory composition in the spraying method according to the present invention comprises a refractory aggregate, a refractory powder,
It contains a binder and a dispersant. Here, as the refractory aggregate, alumina, bauxite, diaspore,
Mullite, kyanite, ban earth shale, chamotte, quartzite, pyrophyllite, sillimanite, andalusite, chromite, spinel, magnesia, zirconia, zircon, chromia, silicon nitride, aluminum nitride, silicon carbide, boron carbide, graphite And at least one selected from carbon, titanium boride and zirconium boride. In the present invention, the term “refractory aggregate” refers to an aggregate having an average particle diameter of more than 30 μm. These refractory aggregates preferably have a particle diameter of 12 mm or less, particularly preferably 10 mm or less. As the particle size, a combination of two or more types, for example, a coarse particle, a medium particle, and a fine particle can be used. In this case, 95% by mass or more of those particles is the largest It is preferable that the ratio of the diameter to the inner diameter of the pressure feed pipe be 1/7 to 1/3.

Further, the refractory powder contained in the refractory composition forms a bonding portion for filling the gap between the refractory aggregates and bonding the refractory aggregates, and has an average particle diameter of 10 μm or less,
Further, a refractory ultrafine powder of 5 μm or less is preferably used. As the refractory ultrafine powder, alumina and fumed silica are preferable. Alumina and fumed silica may be used in the form of alumina sol, silica sol, colloidal silica, or the like, in addition to powder. The refractory powder is preferably contained in an amount of preferably 30 to 60 parts by mass, particularly preferably 40 to 50 parts by mass, based on 100 parts by mass of the refractory aggregate.

As the refractory powder, in addition to the above refractory ultrafine powder, other materials having a particle size larger than that of the refractory ultrafine powder but having an average particle diameter of 30 μm or less can be added. Such materials include alumina, titania, bauxite, diaspore, mullite, ban shale, chamotte, pyrophyllite, sillimanite, andalusite, silicalite, chromite, spinel, magnesia,
Zirconia, zircon, chromia, silicon nitride, aluminum nitride, silicon carbide, boron carbide, titanium boride,
Amorphous silica such as zirconium boride, bentonite or silica. These are used alone or in combination. However, in the present invention, the refractory composition is a clay-like material whose viscosity rapidly increases when water is added, such as those contained in a refractory material of a conventional dry construction method, refractory clay, kaolin. , Bentonite and the like are preferably reduced as much as possible.
The amount is preferably 3 parts by mass or less based on 00 parts by mass.

The binder contained in the refractory composition functions as a binder for amorphous refractories, and alumina cement is preferably used. When alumina cement is used as a binder, the construction body can maintain strength in a wide range from normal temperature to high temperature. As the binder, phosphates such as phosphoric acid and aluminum phosphate, silicates such as sodium silicate and potassium silicate, lignin sulfonate, and water-soluble phenol can also be used. The binder is preferably contained in an amount of preferably 2.5 to 20 parts by mass, particularly preferably 5 to 12 parts by mass with respect to 100 parts by mass of the refractory aggregate.

In the present invention, the dispersant contained in the refractory composition is important, and when the dispersant is not contained, the viscosity increases when the construction water is added to the powdery composition, so that the conveying pipe becomes difficult. It will be blocked. Examples of the dispersing agent include condensed phosphates such as sodium tetrapolyphosphate and sodium hexametaphosphate, carboxylate such as polycarboxylate and polyacrylate, sulfonate such as melamine sulfonate, and β-naphthalene sulfonate. One or more selected from acid salts are preferable, and it is preferable to add 0.02 to 1 part by mass based on 100 parts by mass of the total amount of the refractory aggregate, the refractory powder and the binder of the refractory composition.

FIG. 1 is a schematic view for carrying out a typical spraying method of the present invention. A powdery refractory composition 2 containing the above-mentioned components and sufficiently mixed is supplied to an air carrier 1. Is fed into the conveying pipe 3 in the form of powder. There is no particular limitation on the air flow carrier as long as it can convey the powder by air. For example, a spraying machine can be used. Compressed air is usually supplied from the compressor 7 as an airflow source.
The inner diameter of the transport pipe 3 used here is preferably 65 m
m or less is preferable. If the inner diameter of the transfer pipe exceeds 65 mm, the spray amount per unit time becomes too large, and if the inner diameter is too small, pressure loss occurs. Especially, it is preferably 38 mm or more and 65 mm or less.

Although the length of the transfer pipe 3 is related to the capacity of the airflow transfer device 1, the present invention is characterized in that the transfer can be carried out in a powder form and can be performed over an extremely long distance. In the present invention, the transport distance, which was at most about 100 m in the wet spraying method, can be as long as 200 m. The transport pipe 3 includes an airflow transport device 1 and a spray nozzle 6.
Is not particularly limited as long as it can be connected, and a known metal pipe or rubber hose can be used.

Construction water is added to the refractory composition 2 transported in the transport pipe 3 by a construction water supply unit 4. The position of the construction water supply unit 4 is preferably 1 to 50
m. When the addition of water is added at a position closer than the above, before the refractory composition 2 and the working water are sufficiently mixed, a quick setting agent is added, and solidification of the refractory composition 2 starts. It is not preferable. On the other hand, when water is added at a position farther from the above, the pressure resistance is increased by the addition of water, and the conveying pipe tends to be blocked due to insufficient conveying force with compressed air, which is not preferable. The addition of water is 3 to 10 m more than the quick-setting agent supply unit 5.
Upstream is preferred.

The amount of construction water added to the refractory composition 2 in the present invention is substantially the entire amount of construction water necessary for spraying construction of the refractory. Here, substantially means almost all the required amount, and in some cases a small amount of water can be added at other positions. For example, a small amount of water is added to the amorphous refractory composition 2 to prevent the powder from rising,
It may be a so-called premoist. In order to make such a premoist, a pre-dampener or the like can be appropriately used.
According to the present invention, the refractory composition does not become so viscous as to adhere to the transport pipe even after it becomes wet due to the addition of water. Although it is a peculiar phenomenon about an object, it is not necessarily something that does not fit theoretically.

For example, in studies on the structure of powder, water and air dispersions, generally these three systems can take various structures, but the wet state of the refractory composition in the transport tube of the present invention is So-called “Fuji (II) region” in which air is trapped in continuous particles of powder and water (Umeya: Gakushin 136)
Committee, the non-standard refractory construction technology council study group material), for this purpose, the wet refractory composition of the present invention,
It is assumed that they are transported while floating in the transport pipe. However, this is a presumption of the mechanism and does not restrict the interpretation of the present invention.

When the powdery refractory composition 2 is fed into the transport pipe 3, the irregular refractory 2 is transferred from the irregular refractory composition storage bag 9 containing the refractory composition by the quantitative transporter 8. The supply to the airflow conveyor 1 is no different from the conventional construction method.

Next, a quick-setting agent is added to the wet refractory composition 2 at a quick-setting agent supply unit 5. The addition of the quick setting agent is carried out preferably 0.3 to 2.5 m upstream from the tip of the spray nozzle 6. When the setting agent is added at a position closer than the above, the coagulating effect is not exhibited because the setting agent is not sufficiently uniformly mixed with the refractory composition. On the other hand, when the quick setting agent is added at a position farther than the above, the refractory composition 2 solidifies in the middle of the transport pipe 3, and
There is a possibility that the transfer pipe 3 and the spray nozzle 6 may be closed.

Powders or liquids can be used as the quick setting agent. In order to minimize the amount of water in the clay to be sprayed and maintain good refractory properties, a powder quick-setting admixture is preferably used. When a quick-setting agent of an aqueous solution is used, it is preferable to use an aqueous solution that is as dense as possible because the denseness of the construction body after spraying hardly decreases.

A device capable of uniformly controlling the amount of the powder to be added can be preferably used for the addition of the quick-setting agent to the powder. Usually, a device for adding the quick-setting agent using compressed air as a carrier is used. Also, when a liquid quick-setting agent is used, a liquid pump capable of uniformly controlling the supply amount is preferable, and is appropriately selected according to the type of the quick-setting agent to be used.
A diaphragm pump, a rotating positive displacement single-shaft eccentric screw pump, and the like are preferable.

The quick-setting agent used in the present invention includes silicates such as sodium silicate and potassium silicate, aluminates such as sodium aluminate, potassium aluminate and calcium aluminate, sodium carbonate and potassium carbonate. , Carbonates such as sodium hydrogen carbonate, sulfates such as sodium sulfate, potassium sulfate, magnesium sulfate, C
_{aO · Al 2 O 3, 12CaO} · 7Al 2 O 3, CaO · 2
_{Al 2 O 3, 3CaO · Al} 2 O 3, 3CaO · 3Al 2 O 3
One or more selected from calcium aluminates such as CaF ₂ , 11CaO · 7Al ₂ O ₃ · CaF ₂ , calcium oxide, calcium hydroxide, calcium chloride, and composites or mixtures thereof. In addition, without being limited to the above, known substances called quick-setting agents and flocculants can also be used.

Since the addition amount of the quick-setting agent varies depending on the type of the quick-setting agent, the injection amount is adjusted according to the type of the quick-setting agent and the length to the spray nozzle after the quick-setting agent is injected. Is preferred. In the case of a liquid quick setting agent, it may be diluted, or in the case of a powder quick setting agent, it may be used as it is or as a liquid dispersed or dissolved in a medium with water or the like.

Among the above-mentioned quick-setting agents, it is preferable to use a sodium aluminate powder or an aqueous solution because they are easily available, inexpensive, and have excellent properties. Since sodium aluminate has a high melting point, it does not lower the refractory of the refractory, and when injected into the refractory composition, it hydrolyzes to form a gel of Al (OH) _{3 in} addition to NaOH, thereby rapidly producing the refractory composition. Let it cure.

The amount of the quick-setting admixture is 0.05 to 100 parts by mass of the refractory composition excluding the dispersant, based on the dry weight.
Preferably it is 3 parts by mass. If it is less than 0.05 parts by mass, even if it is a quick-setting agent with good performance, there is a risk that the refractory that has been sprayed will run down due to insufficient quick-setting speed, and if more than 3 parts by mass is injected, It hardens rapidly and makes spraying work difficult, and the performance as a refractory such as heat resistance and corrosion resistance deteriorates.

In the spraying method of the present invention, by changing the amount of the quick setting agent added to the refractory composition during spraying, it is possible to obtain a structure having excellent properties such as durability. For example, in the case of repairing a gap in a refractory furnace wall, a quick setting agent is not added at the start of construction, and the final stage of the construction, preferably, a method of injecting the quick setting agent immediately before completion or at the start of construction, a predetermined amount. A method of injecting several to several tens of mass% of quick-setting agent, increasing the amount of quick-setting agent as the construction progresses, and finally injecting a predetermined amount of quick-setting agent. It is. By adopting such a quick-setting agent injection method, there is little or no quick-setting agent in the inside of the construction body, so it has excellent fire resistance characteristics, while there is sufficient quick-setting agent near the surface, so strength A construction body having excellent characteristics can be obtained.

In the spraying method, if necessary, preferably 0.002 to 0.2 parts by mass of a retarder is added to 100 parts by mass of the refractory composition to form an aggregate. Time can be controlled and refractory can be sprayed stably. As the retarder, a weak acid such as oxalic acid, boric acid, malic acid, citric acid, or ligninsulfonate can be preferably used.

Further, in the present invention, a means for promoting uniform mixing of the powdered refractory composition and the working water after adding the working water to the refractory composition 2 conveyed in the transfer pipe 3 is provided. By providing them, both can be mixed more uniformly.
FIG. 2 to FIG. 4 show the means for that.
Indicates a spiral system in which a part of the transport pipe is spirally twisted, and the refractory composition transported by air inside the transport pipe is spirally inverted in the transport pipe to promote mixing. FIG. 3 shows a swirling method in which a compressed air blowing port 13 is provided on a part of the outer circumference of the conveying pipe to forcibly apply a swirl by the compressed air and rotate the refractory composition to promote mixing. FIG. 4 shows a guide plate 14 (preferably at an angle of 45 ° or less) for causing rotation, which is mounted on a part of the inner circumference of the transfer tube, to disturb the internal flow to promote mixing. The plate method is shown.

Thus, the wet refractory composition to which the quick-setting agent has been added is sprayed from the spray nozzle 6 together with the air for transportation. That is, the wet refractory material is sprayed at a high pressure on a furnace wall construction part or the like to be sprayed. The transfer air is released into the outside air due to the impact when it is blown to the furnace wall construction section. After being blown out, the sprayed amorphous refractory rapidly agglomerates due to the effect of the quick-setting agent, and then hardens to form a construction body, and a strong furnace wall is constructed. At the time of construction, a formwork or the like may be used as necessary.

[0037]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the invention in any way.

Example 1 The results of a comparative test of the constructions obtained by the spraying method of the present invention and the conventional wet spraying method and the dry spraying method are shown below. Test materials: Table 1 shows the breakdown of the materials used. Test method: 400 mm long x 4 wide by each spraying method
Five spray panels each of 00 mm × 100 mm in thickness were prepared and dried, and the physical properties of the panels were compared.
Summarized in

From Table 2, it can be seen that the spraying method of the present invention has less variation in the physical properties of the refractory after drying than the conventional dry spraying method and wet spraying method. This indicates that the construction body structure constructed by the spraying method of the present invention is more homogeneous than the conventional spraying method. In addition, the construction method of the present invention has good mixability with water and requires less supply of construction water than the conventional wet spray construction method, and as a result, it is understood that the construction body is of good quality.

[0040]

[Table 1]

[0041]

[Table 2]

Example 2 Table 3 summarizes the results of comparison of the number of working steps between the spraying method of the present invention and the wet spraying method. Spraying material: The same material as in Example 1 was used in each case. Spraying location: Preheater cyclone for cement equipment (50m above ground)

[0043]

[Table 3] From Table 3, it can be seen that the spraying method of the present invention significantly reduces the number of work steps and the construction period as compared with the conventional wet spraying method.

Example 3 In the spraying method of the present invention, Table 4 shows the test results on the appropriate positions where the working water is added to the sprayed refractory composition flowing in the conveying pipe. Test material: The same material as in Example 1 was used. Test method: A spray panel (length: 10 mm) was connected while connecting a conveyance pipe with an inner diameter of 38 mmφ and a total length of 100 m, while changing the addition position of construction water, that is, the distance between the construction water supply unit 4 and the quick-setting agent supply unit 5.
(00 cm × 1000 cm in width). Discharge rate 3000kg / hour, spray pressure 0.6MP
a. In the table, the dischargeability was evaluated as ○ when the refractory composition could be transported without adhering to the transport tube, and as X when the refractory composition did not adhere to the transport tube. In the wet state, water was evenly distributed to the details, and ○ was used.

[0045]

[Table 4]

From Table 4, it can be seen that the suitable addition position of construction water in the construction method of the present invention is within a range of 50 m or less.

Example 4 In the spraying method of the present invention, Table 5 shows the results of tests on the appropriate positions where the quick-setting agent was added to the wet amorphous refractory composition. Test materials: The same chamotte refractory composition as in the examples was used. Test method: Connect a conveying pipe with an inner diameter of 38 mmφ and a total length of 100 m, and position the construction water supply unit 4 at 10 m from the quick setting agent supply unit 5.
And the position of addition of the quick-setting agent was changed, and spraying was performed on a spray panel (1000 cm long × 1000 cm wide) to compare the characteristics. At the same time, the panel (400mm × 4mm)
A sprayed sample (00 mm x thickness 100 mm) was prepared and the physical properties were compared. The spray amount was 3000 kg / hour, the spray pressure was 0.6 MPa, and the addition amount of the quick setting agent was constant at 1.0% by mass.

[0048]

[Table 5] From Table 5, it can be seen that the appropriate position for the addition of the quick setting agent in the construction method of the present invention is preferably in the range of 0.3 to 2.5 m.

[0049]

According to the present invention, there is provided a novel spraying method which solves the problems of the conventional wet spraying method and dry spraying method.

That is, according to the construction method of the present invention, the following advantages can be obtained. (1) Since the powdery refractory composition is conveyed by airflow, it is not necessary to knead the sprayed refractory composition by a large mixer, and it is not necessary to use a pump for pumping the kneaded material having a large pressure loss. I do. (2) Since the kneaded material is not in a kneaded state, there is no risk of clogging in the transport pipe, and the distance from the supply destination of the amorphous refractory composition to the spraying point is about 10 m in horizontal distance and about 60 m in high places. Can be transported over long distances of about 200 m
Enables construction in high places up to about 50m. (3) Since the irregular-shaped refractory composition does not adhere to the transfer pipe or remains in the transfer pipe after the construction, maintenance is significantly simplified. (4) Work can be greatly reduced because there is no kneading. (5) The loss of the refractory material due to a decrease in the adhesion to the transfer pipe can be reduced. (6) The obtained sprayed refractory has excellent properties with high strength and uniformity.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a typical spraying method of the present invention.

FIG. 2 shows a spiral method in which a part of a transfer pipe is spirally twisted and a refractory composition conveyed by air inside the transfer pipe is spirally inverted in the transfer pipe to promote mixing.

FIG. 3 shows a swirling method in which a compressed air blowing port is provided on the outer periphery of a part of the transfer pipe to forcibly apply a swirl by compressed air and rotate the refractory composition to promote mixing.

FIG. 4 shows a guide plate system in which a guide plate (with a mounting angle of preferably 45 ° or less) for causing rotation is attached to the inner periphery of a part of the transfer pipe to promote mixing by disturbing the internal flow. Show.

[Explanation of symbols]

1: Air flow carrier 2: Irregular refractory composition 3: Conveyor pipe 4: Construction water supply unit 5: Quick binder supply unit 6: Spray nozzle 7: Compressor 8: Quantitative conveyor 9: Irregular refractory composition storage Bag 10: Construction water flow regulator 11: Construction wall surface 12: Construction refractory 13: Compressed air inlet 14: Guide plate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D075 AA02 AA71 AA85 AA90 CA18 DA19 DB11 DC05 EA02 EA25 EB01 EB03 EB57 EC31 EC37 4G033 AA10 AB01 AB21 BA02 4K051 LA02 LA11 LA17 LJ01

Claims (6)

[Claims] 1. An amorphous refractory composition containing a refractory aggregate, a refractory powder, a binder and a dispersant, is sent in a powder stream in a stream of air into a transport pipe, and is transported while floating in the transport pipe. An irregular shape characterized by adding construction water in the middle of the conveying pipe, carrying airflow thereafter, and then adding a quick-setting agent upstream of the tip of the spray nozzle and spraying it through the spray nozzle. Air-flow type spraying method for refractories. 2. The refractory powder having an average particle diameter of 10 μm.
m or less, and the binder is alumina cement, and the dispersant is a condensed phosphate, carboxylate or sulfonate. Conveying spraying method. 3. The method according to claim 1, wherein the working water is added 1 to 5 times from the addition position of the quick-setting agent.
3. The method according to claim 1 or 2, wherein the refractory is added upstream of 0 m. 4. The method according to claim 1, wherein the quick-setting agent is injected from the tip of the spray nozzle at a distance of 0.3.
4. The method according to claim 1, 2 or 3, wherein the refractory is added upstream of about 2.5 m. 5. The method according to claim 1, wherein after the addition of the construction water, a means for uniformly mixing the construction water and the amorphous refractory composition is provided, and the mixture is further uniformly mixed. Pneumatic conveying spraying method for irregular refractories. 6. A fire-resistant wall constructed by the air-flow-conveying spraying method of the refractory of any one of claims 1 to 5.