JPS60246253A - Manufacture of fibrous refractories - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

BACKGROUND OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing fibrous refractory materials such as alumina, silica, and zirconia.

[Prior art]

Fibrous refractory materials, such as refractory fibrous boards, have conventionally been produced by adding an inorganic binder to refractory fibers such as alumina fibers, which are produced by heating and melt-spinning Ceramic Phi 9-1 cold spinning and then firing. It is manufactured by paper-forming and then heating.

For example, silica tile is made of silica fiber and aluminum/yl?
It is manufactured by adding a binder to a mixture of rosilicate fibers, molding this into a paper, drying it, and firing the dry molded product. However, this method requires a large amount of energy when manufacturing the refractory fibers, and also requires a large amount of energy when firing the molded and dried tile base, so it takes a lot of energy to produce the final product. The problem is that fuel must not be consumed.

In addition, alumina-based fiber I-do is made by adding an inorganic binder to alumina fibers made by firing a fiber precursor obtained by cold spinning at a temperature of 1000°C or higher, forming the fibers, and then drying the fibers. The alumina fibers are produced by sintering the alumina fibers using a binder, or by firing the same for 100 degrees and sintering the alumina fibers with a binder. However, this method also requires firing energy when manufacturing the refractory m-fiber, and further firing energy when manufacturing the board, so there is a problem that multiple tons of fuel must be consumed mainly twice. be. Therefore, it has been difficult to obtain inexpensive zede using conventional methods. Furthermore, since the refractory fibers that have been completely fired, such as alumina fibers, have poor sintering activity, even if they are molded with a binder and sintered, the final product will be alumina). - There is a problem that the strength of the cord is low.

Summary of the Invention [Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and its purpose is to reduce the overall energy consumption required in the production of fibrous refractory material, and to produce a product that can be used for a long time. An object of the present invention is to provide a method for producing a fibrous refractory material that can increase the strength of the fibrous refractory material.

[Structure of the invention]

The present inventors have found that, when producing fibrous refractory materials, the present invention can be achieved by using a fiber precursor that changes into refractory fibers through firing treatment, rather than using already produced refractory fibers. The present invention was completed after realizing that the present invention was effective in achieving the object.

That is, the method for producing a fibrous refractory material according to the present invention involves firing a molded article consisting of a fiber precursor and an inorganic binder that transform into refractory fibers by firing, and converting the precursor into refractory fibers and sintering between the fibers. It is characterized by carrying out the following.

[Effect of the invention] The present invention provides the following effects.

f8+ The firing energy for forming refractory fibers and the energy for sintering between fibers in the molded body are not consumed separately, but the formation of refractory fibers and the sintering between fibers are simultaneously performed in the molded body. Alternatively, since it is performed sequentially, energy consumption can be significantly reduced compared to conventional methods, and therefore, inexpensive fibrous refractory materials can be produced.

(bl) Rather than using completely refractory fibers, the use of unfired fiber precursors and their high sintering activity allows for easy and strong sintering between the fibers (3). Therefore, a strong fibrous refractory material can be obtained.

[Detailed Description of the Invention 1 The fiber precursor used in the present invention is transformed into a refractory fiber by firing it. The fiber precursor can be produced, for example, by the method described in US Pat. No. 4,277,269 and Japanese Patent Publication No. 55-36726. The former method uses 0.3 to 1
．． The method consists of introducing a solution for forming a fiber precursor into a hollow rotating disk having a 5 m hole, and rotating this disk to obtain a fibrous precursor. The latter method also involves extruding a fiber precursor forming solution through one or more apertures into an air stream to form the precursor.

In addition, a primary fiber precursor is formed in the fluid stream by spinning this viscous liquid from the surface of the viscous liquid for forming a fiber precursor, and the secondary fiber precursor is further stretched by fluid pressure. There is also a method consisting of obtaining a secondary fiber precursor.

The solution or (4) viscous liquid for forming a fiber precursor in the present invention includes a solution of a metal salt that changes into a metal oxide by heating and baking, a refractory material such as alumina, silica, zirconia, and magnesia, or iron, titanium, and chromium. metal powder dispersions, polycarbosilane viscous liquids, and mixtures thereof.

Examples of the metal salts include chlorides, sulfates, formates, acetates, zolopionates, butyrates, other alkanoates, and bases of aluminum, iron, zirconium, titanium, helium, chromium, magnesium, yttrium, etc. alkanoates, lactates, silicates, and mixtures thereof.

Examples of the dispersoid used in preparing the dispersion include:
Ultrafine powder of refractories such as alumina, silica, zirconia, and magnesia, used in ordinary refractory bricks, iron,
These include metal powders such as titanium and chromium, colloidal silica, colloidal zirconia, and alumina sol.

In the present invention, a clear liquid or viscous liquid for forming a fiber precursor is prepared using the above-mentioned gold bullion salt and dispersoid in combination or each alone. Since these metal salts and dispersoids are usually solid or powdered, they are dissolved or dispersed. This medium includes water; hydrocarbons such as hexane and petroleum benzene; halogenated hydrocarbons; -hydric alcohols; phenols; ethers and esters; polyhydric alcohols and their ethers or esters, aldehydes; acetals; ketones; Nitro compounds, amides,
amines); sulfur-containing compounds (dimethyl sulfoxide, etc.)
; and mixtures thereof.

In addition, when preparing solutions or viscous liquids for forming fiber precursors, viscosity imparting agents (gluing agents) are used to adjust the viscosity.
Alternatively, a diluent can be added. Examples of the viscosity imparting agent that can be used in the present invention include polyethylene oxide, polyvinyl alcohol, polyacrylic acid,
Synthetic polymers such as polyvinyl acetate; methylcellulose,
Examples include cellulose derivatives such as carboxymethylcellulose, carboxyethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, and cellulose phosphate; starch and its derivatives; animal and plant mucilages such as pectin, sodium alginate, and agar. The amount of the viscosity imparting agent and diluent added may be changed as appropriate depending on the length, diameter, strength, etc. of the target fiber precursor. Furthermore, during this preparation, it goes without saying that various auxiliary agents are added in order to impart various performances to the fiber body and the refractory fiber obtained by firing the same.

The inorganic binder used in the present invention is intended to mutually sinter the fibers in the molded body.

An example of such a binder is basic aluminum chloride [
AI(OH) The binder to be used can be selected in consideration of, for example, the quality of the intended fibrous refractory material. That is, when attempting to produce a fibrous refractory material with high purity of zirconia, zirconium chloride and/or zirco acetate (
7) It is desirable to add Ni. Furthermore, when attempting to produce an alumina-based fibrous refractory material, it is necessary to select colloidal alumina, basic aluminum chloride, or aluminum chloride. In preparing the molded body,
The amount of inorganic binder added to the fiber precursor is 5 to 70 parts by weight based on 100 parts by weight of the fiber precursor as solid content,
Preferably, the amount is between 1 and 2 parts by weight. This is because if the amount added is less than 5 parts by weight, it will not be possible to impart sufficient strength to the fibrous refractory material of the final product, while if it exceeds 70 parts by weight, excessive sintering will occur, impairing the lightness of the final product. It's your body.

In preparing the molded body in the present invention, in addition to the fiber precursor and the inorganic binder, ordinary refractory powder,
For example, powders such as silica, alumina, and zirconia can be added to form a composite material. Furthermore, during this preparation, various auxiliary agents may be added in order to impart various properties to the final refractory material.

Formation of the molded body (8) consisting of the fiber precursor and the inorganic binder can be carried out by various methods depending on the type and shape of the target fibrous refractory material. For example, when manufacturing a plate-shaped fibrous refractory material, that is, a refractory fibrous material See 1, it can be carried out by paper forming. A plate-shaped molded article can be obtained by adding an inorganic binder and a paper-making medium to a fiber precursor of a predetermined violet, and then forming the fiber precursor into a sheet.

In this papermaking process, if a water-insoluble fiber precursor containing polyvinyl acetate, polyacrylic acid, etc. is used as a viscosity imparting agent, papermaking using water as a medium is possible; When using a fiber precursor containing a water-bathable organic viscosity-imparting agent, the precursor must be dried at 100 to 200°C to make it water-insoluble, or a non-aqueous liquid such as kerosene or heavy oil may be used as the papermaking medium. should be used. In addition to this paper forming process, a molded article consisting of a fiber precursor and an inorganic binder can be formed by spraying an inorganic binder onto a certain-shaped aggregate of fiber precursors and immersing the aggregate in a binder liquid. I can do one thing.

The molded body is subjected to a normal drying process as necessary.

In the present invention, the purpose of firing a molded body made of a fiber precursor and an inorganic binder is to make the precursor into a refractory fiber and to sinter the fibers. The firing temperature is appropriately selected depending on the desired refractory material.

If the optimal temperature for refractory fiberization and the optimal temperature for firing are the same,
heated to that temperature. Furthermore, if the optimum temperatures for both are different, heating can be carried out by sequentially heating to each temperature. The final product is heated to 900°C to 1500°C when the final product is alumina I-do, to 600°C to 1000°C when it is a siliceous mate, and to 1300°C to 1800°C when it is a zirconia mate. can be fired.

The fibrous refractory material produced by the method of the present invention can be used as an insulating lining material for various industrial kilns, lids for metal melting furnaces, ladles, tundishes, etc., P overlay materials, and thermal buffering materials for preventing heat spalling in refractory bricks. It is used for materials installed on the surface of refractory bricks, burner tiles, small electric furnace lining materials, etc.

〔example〕

The invention will now be explained by way of example.

Example 1 Zirconia powder of 0.1μ or less) parts by weight, zirconium oxychloride (zirconium oxychloride, Zr0C12) 6
Water-insoluble fiber precursor (length 5 to 21) III11 diameter 2 to 5 parts by weight and 5 layers of polyethylene oxide
5μ) was prepared. Part by weight of an aqueous solution of zirconium chloride (ZrOCl2) having a concentration of 50% was added to 1 part of 100 m' of this fiber precursor, and this was formed into a paper to obtain a molded article. This molded body was dried at 100° C. for U hours. The dried molded body was fired at 1600°C to produce a zirconia-based fibrous mate.

The properties of the obtained mate are shown in Table 1.

Comparative Example 1 Zirconium acid chloride (ZrOCl2) was added to zirconia powder and calcined zirconia fibers using a conventional method, and a molded product was obtained by paper forming, and this molded product was dried at 100° C. for a while. The dried molded body was fired at 1600°C to produce a conventional zirconia-based fibrous Zee P (11).

The properties of the obtained Zee 1 are shown in Table 1.

Example 2 A water-insoluble fiber precursor (length 100 to 2001 m, diameter 7
~10μ) was prepared. 120 parts by weight of a basic aluminum chloride aqueous solution having a concentration of 30% was added to 100 parts by weight of this fiber precursor, and this was formed into a paper to obtain a molded article. This molded body was dried at 100° C. for a while. 100 dried molded bodies
An alumina-based fibrous mate was produced by firing at 0°C.

The properties of the obtained mate are shown in Table 1.

Comparative Example 2 By a conventional method, zirconium oxychloride (ZrOCl2) was added to calcined alumina fibers, and a molded body was obtained by paper forming.
This molded body was dried at 100° C. for U hours.

The molded body was fired at 1000°C to produce a conventional alumina-based fibrous mate.

The properties of the obtained Z-r are shown in Table 1.

(2) As is clear from the table above, the manufacturing method of the present invention makes it possible to obtain a fibrous board that is lighter and stronger than conventional boards.

Example 3 A water bathable fiber precursor (length 1
~5 dragons, diameter 2-4μ) were prepared. This water-soluble fiber precursor has #! l Zirconium chloride (ZrOCl
2) Powder 4 (adding J Chonghuibu and Kerosene Guanjubabu,
This was paper-formed to obtain a molded body. This molded body is 160
A zirconia-based fibrous board was manufactured by firing at 0°C.

The obtained solid had a bulk specific gravity of 0.4 and a bending strength of 2.
0 kp/(m2), and had substantially the same characteristics as the board of Example 1 described above.

Applicant's agent Kiyoshi Inomata (15)

Claims (1)

[Claims] A fibrous refractory material characterized in that a molded body consisting of a fiber precursor and an inorganic binder that is converted into a refractory fiber by firing is fired to convert the precursor into a refractory fiber and to sinter the fibers. Production method.