JPH10291867A - Spray castable refractory material containing aluminum-based metal powder and its executing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spray castable refractory material and its executing method without causing an explosion, etc. even if rapid drying is executed just after spray executing is finished and even if the spray executing is executed to a body to be executed in a high temp. state. SOLUTION: In a spray castable refractory material and the executing method of the spray castable refractory material, the 0.03-1.0 wt.% sum of one or more kinds of an aluminum-based metal powder such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy and a hydration reaction accelerating agent of the aluminum based metal powder and added to the total solid contents of the castable refractory material. The material is used by adding the aluminum based metal powder, the hydration reaction accelerating agent and water just before the executing in the vicinity including a spray nozzle part of by mixing beforehand one or two among the aluminum-based metal powder, the hydration reaction accelerating agent and the water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sprayable amorphous refractory containing aluminum-based metal powder used for a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator, and the like, and a method of applying the same.

[0002]

2. Description of the Related Art In recent years, the use of irregular-shaped refractories has been widespread due to a shortage of skilled workers for brick construction, labor saving and cost reduction, and casting, spraying, ramming,
A construction method such as a vibration iron construction is selected depending on the situation.

[0003] Among these irregular refractory construction methods,
Spraying construction is classified into three types of construction methods: a dry method, a semi-wet method, and a wet method, and all of them are methods of spraying an irregular-shaped refractory to a container or the like to be constructed. The dry method is a construction method in which an amorphous material in a dry powder state is pneumatically fed and water is added and sprayed at a spray nozzle portion as disclosed in Japanese Patent Application Laid-Open No. 60-186482. In the semi-wet method, for example, as disclosed in Japanese Patent Application Laid-Open No. 62-36070, a semi-wet state amorphous material to which a part of water has been previously added and kneaded is pressure-fed, and a pressure feeding pipe (hose) in the middle of the pressure feeding. Alternatively, in the spray nozzle portion, either one of the binder and the quick-setting binder and the remaining water are added and sprayed. The wet method is described in, for example, Japanese Patent Application Laid-Open No. 54-6100.
As disclosed in Japanese Patent Publication No. 5 (1994), an amorphous material for wet spraying containing a binder such as cement preliminarily kneaded with a necessary construction amount of water is pressure-fed, and a pressure-feeding pipe or a spray nozzle portion in the middle of pressure-fed. In this method, a quick setting agent is added and sprayed.

On the other hand, the addition of aluminum or aluminum alloy to amorphous refractories is disclosed in, for example,
As disclosed in Japanese Patent No. 784777, the method is used to generate a vent hole in a construction body by generating hydrogen gas due to hydration of aluminum powder so that explosion or the like does not occur even if the construction body is rapidly dried. I have.

[0005]

Generally, in the case of spraying an amorphous refractory containing aluminum or an aluminum alloy, so-called aluminum-based metal powder, the aluminum-based metal powder is mixed during the kneading process of the amorphous material and water. Or, when water is added to the amorphous material, the hydration reaction does not occur, but after 4 to 6 hours from the end of spraying, the hydration reaction starts and hydrogen gas is generated, and the vent hole is opened. This will cause the explosion prevention effect. Therefore, the addition of aluminum-based metal powder to the water-based amorphous material is effective as a means for improving the drying characteristics so that the construction body does not explode even if it is rapidly dried, but the generation of hydrogen gas due to hydration does not occur. If drying is not started after a certain progress, improvement of drying characteristics cannot be expected. That is, in the case of spraying construction, the construction body develops strength in a short time after completion of the construction, but if drying is started immediately, the improvement of the drying characteristics cannot be expected. In addition, when spraying is performed in a state where the object to be repaired is at a high temperature for the purpose of repair, since the amorphous refractory is sprayed on the object to be dried and drying starts at the same time, the above-described drying is performed. No improvement in properties can be expected.

The present invention relates to an amorphous refractory for spraying, which does not generate explosions even if it is rapidly dried immediately after the spraying is completed, and which does not generate explosion even when sprayed on a workpiece in a high temperature state. It is to provide a method.

[0007]

The amorphous material for spraying containing the aluminum-based metal powder according to the present invention comprises aluminum, aluminum-silicon alloy, aluminum-magnesium alloy and the like in the total solid content of the amorphous refractory. One or more of the aluminum-based metal powders of
1.0% by weight and the hydration reaction accelerator for the aluminum-based metal powder are added.

[0008] The method of applying the amorphous refractory for spraying according to the present invention is characterized in that one or two or more aluminum-based metal powders of aluminum-based metal powder such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy, etc. ) A hydration reaction accelerator excluding water. (3) When adding water, one or more of the above three are added at or near the spray nozzle portion.

In addition, one or more kinds of aluminum-based metal powders such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy, etc. are previously mixed with the amorphous material, and at the spray nozzle portion or in the vicinity thereof, A hydration accelerator in the form of a dry powder or an aqueous solution is added.

Also, one or more of aluminum-based metal powders such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy and the like and a dry powder hydration reaction accelerator are mixed in advance with the amorphous material. Dry spraying method may be used.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The refractory raw material aggregate and fine powder used in the amorphous refractory of the present invention are generally used as an amorphous material and are not particularly limited. For example,
Electrofused or sintered alumina, calcined alumina, bauxite,
Electrofused or synthetic mullite, sillimanite, andalusite, kyanite, ban shale, chamotte, olivine, quartzite, fused silica, electrofused or sintered magnesia, electrofused or sintered spinel, evaporated silica, titania, electrofused Or sintered zirconia, zircon, chromite, fused or sintered magnesia lime, fused zirconia arm light, fused alumina zirconia, silicon carbide, silicon nitride, clay, natural or artificial graphite, petroleum coke, pitch coke , Anthracite, carbon black, amorphous carbon such as pitch, etc., and one or more of these are used. Further, as the binder and the deflocculant, those used for ordinary amorphous refractories for spraying can be used.

Aluminum-based metal powders such as aluminum, aluminum-silicon alloys, aluminum-magnesium alloys, etc., have a particle size of 1 mm or less, preferably 0.1 mm or less, usually used for amorphous refractories. 1 mm or less in a solid content of 100% by weight, a total of one or more
Use 3 to 1.0% by weight. When the amount is limited to 0.03% by weight or more, if the amount is less than 0.03% by weight, the amount of hydrogen gas generated by hydration of the aluminum-based metal powder is small. This is because the effect of preventing explosion or the like that occurs when spraying is performed on the workpiece in a high temperature state is small. The reason why the amount is limited to 1% by weight or less is that if the amount of use is more than 1% by weight, hydrogen gas is generated too much, and the sprayed construction body may crack or peel off.

As the hydration reaction accelerator for the aluminum-based metal powder, when an amorphous material for dry spraying containing the aluminum-based metal powder, water and the hydration reaction accelerator are mixed, Preferably, a liquid, powder or suspension having an action of initiating the hydration reaction of the aluminum-based metal powder within 10 minutes is used. Examples of the hydration reaction accelerator having such an action include, but are not limited to, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkali metal aluminates such as sodium aluminate and potassium aluminate. Can be used. The amount of addition is not limited, but usually, the above-mentioned effect is produced when the amount of addition is in the range of 0.1 to 3% by weight based on the solid content of 100% by weight. Among the hydration reaction accelerators for aluminum-based metal powders, there are, for example, alkali metal aluminates that act as a quick setting agent in spraying irregular refractories, in which case one kind of additive is used. Can also serve as a hydration accelerator and a quick-setting agent.

In the spraying, one or more aluminum-based metal powders such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy,
Hydration reaction accelerator excluding water, and when mixing or adding water, the aluminum-based metal powder, hydration reaction accelerator and water may be added in the vicinity including the spray nozzle immediately before construction, or The aluminum-based metal powder,
One or two of the hydration accelerator and water are mixed in advance and used.

[0015] That is, the method of adding the hydration reaction accelerator in the present invention is slightly different depending on the construction method.

In the case of dry spraying, there are two methods. One method is to pump an amorphous material for dry spraying containing an aluminum-based metal powder and a powder (solid) hydration reaction accelerator. , A method of adding water with a pressure feeding pipe (hose, the same applies hereinafter) or a spray nozzle part in the middle of the pressure feeding, and another method of feeding an amorphous material for dry spraying containing aluminum-based metal powder and feeding the water in the middle of the pressure feeding. It is constructed by a method of adding a hydration reaction accelerator for liquid, powder, or suspension and water with a pressure feed pipe or a spray nozzle. In this case, the hydration reaction accelerator and water may be added separately or simultaneously.

In the case of semi-wet spraying, an amorphous material for semi-wet spraying containing an aluminum-based metal powder kneaded with a predetermined amount of a part of water is usually fed under pressure, and a pressure feeding pipe or spraying partway through the pressure feeding is performed. At the nozzle, the hydration reaction accelerator for liquid, powder or suspension and the remaining water are added. In this case, the hydration reaction accelerator and water may be added separately or simultaneously.

In the case of wet spraying, usually, an amorphous material for wet spraying containing an aluminum-based metal powder kneaded with a predetermined amount of water is pressure-fed, and the liquid is fed through a pressure-feeding pipe or a spray nozzle portion during the pressure-feeding. It is constructed by adding a powder or suspension hydration accelerator. The above-described method of adding the hydration reaction accelerator is a description in the case where aluminum-based metal powder is mixed in advance with the amorphous material, but aluminum-based metal powder is added in the vicinity including the spray nozzle portion. It can also be implemented.

The method of adding the binder and the quick-setting agent is not different from the usual dry, semi-wet or wet spraying method. When adding a binder or a quick-setting binder in the vicinity including the blowing nozzle and blowing the amorphous material, the binder and the quick-setting binder, and the hydration reaction accelerator of the aluminum-based metal powder, respectively, They may be added in different systems or simultaneously. It should be noted that the aluminum-based metal powder, its hydration accelerator, and water are not simultaneously contacted until immediately before spraying. That is, when the hydration reaction accelerator is an aqueous solution or suspension water, the aluminum-based metal powder and the hydration reaction accelerator are prevented from reacting with each other until immediately before spraying.

[0020]

Examples Examples and comparative examples according to the present invention are shown in Tables 1, 2 and 3.

With respect to the application of Examples and Comparative Examples defined in the present invention, as the aluminum-based metal powder, "AC100" which is an aluminum powder manufactured by Toyo Aluminum Co., Ltd.
No. 3) was used, and a 20% by weight aqueous sodium hydroxide solution was used as a hydration reaction accelerator, but is not limited thereto. As the refractory raw material, sintered alumina having a purity of 99.7% by weight, purity of 99.6% by weight, and an average particle diameter of 1.5 μm.
Of calcined alumina having a purity of 96.0% by weight and an average particle size of 0.2
Using 8 μm evaporated silica and ball clay, alumina cement “Lafarge S”
ECAR71 ”, sodium polyacrylate as a deflocculant, lime powder, 50% by weight calcium hydroxide suspension, or 40% by weight aqueous potassium aluminate solution (potassium aluminate is water ), But is not limited thereto. The average particle size of the fine powder is a value measured by a laser diffraction method.

The item "Construction state" shown in the table is about 2
spraying construction were construction body was left at room temperature for 24 hours to a thickness of about 0.15m in chamotte brick surface area of m ^2,
A mark "◎" indicates that the construction body did not have any cracks or peeling, and a mark "に は" indicates that a very small crack was slightly generated on the surface but no practical problem was found.
Those that are judged to be practically difficult due to occurrence of cracks or peeling are marked with “x”.

The item "explosion resistance" shown in the table refers to the construction surface of a construction body sprayed to a thickness of about 0.15 m on a chamotte brick having an area of about 0.5 m ^2. 10 minutes after the completion of the construction, one side was heated in a gas burner furnace heated to 600 ° C., and no “cracked” or “peeled” was generated on the construction body. The symbol "裂" indicates that a small crack was slightly generated but no practical problem was found, and the symbol "x" indicates that cracking or peeling occurred and was judged to be difficult to use. I have filled in.

Table 1 shows examples and comparative examples of amorphous refractories for dry spraying.

[0025]

[Table 1] Examples 1 to 5 are amorphous refractories for dry spraying that satisfy the conditions defined by the present invention. In the table, the amounts of water and the hydration reaction accelerator added are indicated by an outer appearance (ten) with respect to the other solid content of 100% by weight. In this example and the comparative example, spraying was performed by a method of adding water and a hydration reaction accelerator at the spray nozzle portion, but the same effect can be obtained if the method described in the embodiment of the present invention. can get.

In Comparative Example 1, the amount of aluminum used was less than the specified range of the present invention (0.03 to 1% by weight).
(01% by weight), cracks were generated when it was quickly dried immediately after the application, and the explosion resistance was inferior to that of the examples of the present invention.

In Comparative Example 2, the amount of aluminum used was more than the specified range (0.03 to 1% by weight) of the present invention (1.5 to 1% by weight).
% By weight), cracks occurred after the construction, and a satisfactory construction was not obtained.

In Comparative Example 3, since no hydration reaction accelerator was added, cracking and peeling occurred when rapidly dried immediately after the application, and the explosion resistance was inferior to that of Examples of the present invention. there were.

Table 2 shows examples and comparative examples of the semi-wet type refractory for spraying.

[0030]

[Table 2] Examples 6 to 10 are semi-wet spraying irregular shaped refractories satisfying the conditions defined by the present invention. The amounts of water, quick-setting agent, and hydration reaction accelerator added at the nozzle portion in the table are indicated by outside values (indicated in tens) with respect to the other solid contents of 100% by weight. In this embodiment and the comparative example, water was sprayed at the spray nozzle portion.
Spraying was performed by a method of adding a quick setting agent and a hydration reaction accelerator, but the same effect can be obtained with the method described in the embodiment of the present invention.

In Comparative Example 4, the amount of aluminum used was less than the specified range (0.03 to 1% by weight) of the present invention (0.0 to 1% by weight).
(01% by weight), cracks were generated when it was quickly dried immediately after application, and the explosion resistance was inferior to that of the examples of the present invention.

In Comparative Example 5, the amount of aluminum used was more than the specified range (0.03 to 1% by weight) of the present invention (1.5 to 1.5% by weight).
% By weight), cracks occurred after the construction, and a satisfactory construction was not obtained.

In Comparative Example 6, since no hydration reaction accelerator was added, cracking and peeling occurred when rapidly dried immediately after application, and the explosion resistance was inferior to that of the Example of the present invention. there were.

Table 3 shows examples of the amorphous refractory for wet spraying and comparative examples.

[0035]

[Table 3] Examples 11 to 15 are amorphous refractories for wet spraying that satisfy the conditions defined by the present invention. In the table, the amounts of the quick-setting agent and the hydration reaction accelerator added at the nozzle portion are indicated by an outer number (indicated by ten) with respect to the other solid content of 100% by weight. In this example and the comparative example, spraying was performed by a method of adding a quick-setting agent and a hydration reaction accelerator in a spray nozzle portion, but the method described in the embodiment of the present invention is equivalent. The effect is obtained.

In Comparative Example 7, the amount of aluminum used was less than the specified range of the present invention (0.03 to 1% by weight).
(01% by weight), cracks were generated when it was quickly dried immediately after application, and the explosion resistance was inferior to that of the examples of the present invention.

In Comparative Example 8, the amount of aluminum used was more than the specified range (0.03 to 1% by weight) of the present invention (1.5 to 1.5% by weight).
% By weight), cracks occurred after the construction, and a satisfactory construction was not obtained.

In Comparative Example 9, since no hydration reaction accelerator was added, cracking and peeling occurred when rapidly dried immediately after application, and the explosion resistance was inferior to that of Examples of the present invention. there were.

[0039]

The present invention relates to an amorphous refractory for spraying which can be used for a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator, etc., and which can be quickly dried immediately after spraying, or In addition, even when sprayed on a work piece in a high temperature state, there was no occurrence of explosion or the like, and a highly durable sprayable refractory material could be obtained.

Further, a construction method which can make full use of the characteristics of the amorphous refractory of the present invention has become possible.

Claims (4)

[Claims] 1. An aluminum-based metal powder such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy or the like in a total solid content of an amorphous refractory.
An amorphous refractory for spraying, comprising an aluminum-based metal powder to which at least 0.03 to 1.0% by weight of the above-mentioned seeds and a hydration reaction accelerator for the aluminum-based metal powder are added. 2. An aluminum-based metal powder such as (1) aluminum, an aluminum-silicon alloy, an aluminum-magnesium alloy, or the like; (2) a hydration reaction accelerator excluding water; and (3) water. The method of claim 1, wherein one or more of the three are added at or near a spray nozzle. 3. One or more of aluminum-based metal powders such as aluminum, aluminum-silicon alloys, aluminum-magnesium alloys, etc., are previously mixed with an amorphous material, and at or near the spray nozzle portion, The method according to claim 1, further comprising adding a hydration reaction accelerator in the form of a dry powder or an aqueous solution. 4. An amorphous material in which one or more of aluminum-based metal powders such as aluminum, aluminum-silicon alloy, aluminum-magnesium alloy, and the like, and a powdered hydration reaction accelerator are mixed in advance. 2. The method for applying an amorphous refractory for spraying according to claim 1, wherein the refractory is spray-dried.