JPH08169772A - Baking repairing material - Google Patents

Abstract

PURPOSE: To obtain a baking repairing material excellent in flow spreadability and adhesiveness in a hot state and excellent also in work efficiency and physical properties by mixing refractory aggregate with a binder forming carbon bonds in a hot state and a specified diphenyl type fluidizing aid. CONSTITUTION: Refractory aggregate (A) such as silica, alumina, chromia, magnesia, calcia or silicon carbide is mixed with a binder (B) made of a substance forming carbon bonds in a hot state, e.g. pitch and a fluidizing aid (C) made of diphenyl and/or diphenylamine to obtain the objective baking repairing material. The component B made of pitch having <=300 deg.C softening point and the component C are added by 5-40 pts.wt. and 0.5-40 pts.wt. per 100 pts.wt. of the component A, respectively. An antioxidant for carbon such as Al powder and a dust generation inhibitor such as liq. paraffin may further be blended. The resultant repairing material is suitable for hot repair of various refining furnaces and vessels.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bake repair material for hot repairing various refining furnaces and vessels.

[0002]

2. Description of the Related Art As one of the methods for hot repairing a melted portion of a furnace wall refractory of various kilns, a hot-throw baking repair method is widely adopted. This is generally made by kneading a refractory material with pitch and tar that function as a binder to form a kneaded clay. However, in addition to the drawback that it takes a long time to bake, it also has the drawback that smoke and offensive odor are severe during use.Therefore, phenol, etc., is obtained from the product obtained by acid decomposition of cumene hydroperoxide benzene as a non-tar binder. Kneading with a pot residue obtained by distilling off and dissolving it in an organic solvent (JP-A-59-59)
No. 45975), or a mixture in which a frit or a frit and a powder resin are added and kneaded with a polyhydric alcohol solution (JP-A-63-63)
-31435) is publicly announced.

On the other hand, the powdery form (including the form which is wet but can be regarded as a powdery form for handling, the same applies hereinafter) includes pitches within a specific range and granular and liquid phenols. Resins used as binders to reduce environmental and hygiene defects of tar and pitch (Japanese Patent Laid-Open No. 60-235772), those containing pitch as binders in order to improve fluidity, heavy oil and creos Those to which sort oil or the like is added (Japanese Patent Laid-Open No. 1-150790),
A baking material is prepared by adding an inorganic compound having water of crystallization so that this water of crystallization is in a mud-showing state due to the water content when dehydrated in a red-hot furnace (JP-A-2-26).
No. 874), in which lactams are added as a fluidization aid to a material containing pitch or a phenol resin in order to improve flow developability (Japanese Patent Laid-Open No. 6-157149) and the like.

[0004]

From the viewpoint of manufacturing, it is inconvenient for the bake repairing material to be used and handled, and the material in the form of a dough is inconvenient because the liquid may flow out even from a small crushed bag portion. It is also a very complicated production. On the other hand, the powder form does not have the above-mentioned drawbacks at all. However, the powdery one has a poorer flow spreadability than the kneaded one, and the adhesiveness to the furnace wall is poor, so that there has been no satisfactory durability up to now.

In this respect, the method disclosed in Japanese Patent Laid-Open No. 6-157149, which is characterized by using a fluidization aid, is a method for advancing the drawbacks of the powdery baking repair materials to date. However, it can be said that the use of ε-caprolactam as a fluidization aid disclosed in JP-A-6-157149 has a problem in storage stability. That is, ε-caprolactam is a substance having a strong hygroscopic property, and is likely to cause hydration of dolomite and magnesia, and there is a problem in storage stability especially in summer. Also, the adhesive strength is not sufficient as compared with the conventional one.

[0006]

Means for Solving the Problems In the development of a powdery baking repair material, the present inventors searched various substances as fluidization aids for pitch and phenol resin, and as a result, diphenyl or diphenylamine was the best. That is, the present invention has been completed. That is, the present invention provides a bake repair material comprising a refractory aggregate, a substance that forms a carbon bond during heat as a binder, and diphenyl or (and) diphenylamine as a fluidization aid.

The refractory aggregate used in the present invention is not particularly limited, and any suitable one can be used which is suitable for the composition of the base material used in the portion to be repaired. That is, so-called acidic oxides such as silica, zircon and zirconia, neutral oxides such as alumina and chromia, basic oxides such as magnesia, calcia and dolomite, and non-oxides such as carbon materials, silicon carbide and silicon nitride. One kind or two or more kinds of the above can be appropriately used.

Next, as the substance which forms a carbon bond by heat, pitches and phenol resins which are commonly used as organic binders can be used. The amount used gives the necessary fluidity suitable for the repaired part and is used in such an amount that carbon bonds are sufficiently formed, but the amount used is usually 5 to 40 parts by weight with respect to 100 parts by weight of the refractory aggregate. I need.
If this amount is less than 5 parts by weight, the flow developability will be insufficient, and the strength and adhesiveness will be poor. If it is used in an amount of 40 parts by weight or more, the porosity of the construction body becomes large and the durability becomes poor. The pitch used in the present invention may be coal-based or petroleum-based, and the softening point thereof should be 300 ° C. or less because it has the role of quickly melting by the furnace heat and making the entire baking repair material into a fluid state. Limited but usually 100
A temperature of up to 150 ° C is desirable. As the phenol resin, a so-called novolac type thermoplastic resin is preferable, and various solid resins such as powder and flakes can be used. The melting point is preferably 120 ° C. or lower.

Both diphenyl and diphenylamine as fluidization aids are powders (solids) at room temperature and have no hygroscopicity as seen in ε-caprolactam, so there is no problem in storage and fire resistance. It can be said that it is easy to mix with the aggregate and is convenient in manufacturing. These are not inferior to ε-caprolactam in flow developability, and are superior to ε-caprolactam in adhesiveness to the furnace wall, and both can be used alone as a fluidization aid, but the baking temperature and It can also be used in combination for the purpose of adjusting the flow developability according to the heat capacity of the kiln. The amount used is 0.5 to 40 parts by weight based on 100 parts by weight of the refractory material, depending on the required fluidity.
Use of 0 parts by weight or more is not desirable because it increases the porosity of the construction body and prolongs the baking time. Further, when used in an amount of 0.5% or less, almost no effect as a fluidization aid is observed.

The fluidizing aid must be compatible with the pitch and the phenol resin melted by the heat of the furnace, because it must lower the viscosity and accelerate the flow. For example, even if polyethylene glycol, which is easily melted and becomes a low-viscosity liquid by furnace heat but has little compatibility with pitch or phenolic resin, is used, the melting of these is delayed, and the fluidization aid is increased simply by increasing the baking time. It does not function as an agent. In addition, as the fluidization aid, it is preferable that the fluidization aid itself is melted by furnace heat, and is desirably melted at a temperature lower than that of the pitch or the phenol resin to lower the viscosity. In this respect, the melting points of diphenyl and diphenylamine are about 70 ° C. and 52 ° C., respectively, which is convenient. When a baking repair material using diphenyl or (and) diphenylamine as a fluidization aid is placed in a red-hot furnace, the binder and the pitch or phenol resin blended as a fluidizing agent melts, and diphenyl or (And) Diphenylamine compatibilized makes the whole mud-shown with low viscosity, flow-developed, penetrated even into the details of the damaged furnace wall and packed densely, and after solidification it has excellent strength and adhesion due to carbon bonding. Develop sex.

In addition to the above, in the product of the present invention, metal powder such as aluminum powder, silicon powder, and ferrosilicon powder, which functions as a carbon antioxidant, and boron carbide (B
₄ C) can also be used. Further, for convenience of handling such as prevention of dust generation at the time of addition, it is also possible to premix and wet with an organic solvent such as liquid paraffin, isoparaffin, ethanol and the like, kerosene, heavy oil, water and the like.

[0012]

EXAMPLES Examples of the present invention and comparative examples are shown in Table 1. Examples 1 to 6 are examples of the powdery baking repair material of the present invention, and Comparative Examples 1 to 4 use pitch, or pitch and thermoplastic phenolic resin powder in combination as a binder, and use a fluidization aid. And the examples using Pitch as a binder and ε-caprolactam as a fluidization aid.

The characteristic value of each composition shown in Table 1 is 1
It is a value when tested in a test furnace maintained at 100 ° C.
That is, as the spread area index, the spread area when 200 g of the sample was dropped on a magnesia brick set in a test furnace (held at 1100 ° C., the same applies hereinafter) was used as Comparative Example 1.
Is indexed to 100. The curing time is the time until 500 g of the sample is placed in an iron container having an inner diameter of 100 mmφ and a depth of 70 mm and placed in a test furnace to melt and solidify the sample. The adhesive shear strength is determined by placing an iron frame measuring 70 mm in length x 80 mm in width x 50 mm in depth on a magnesia brick set in a test furnace, in which 500 g of a sample is placed.
Was put into a magnesia brick by baking to bond it, taken out of the furnace, cooled, and measured. The physical properties after hot working are measured by putting 2 kg of a sample in an iron container having an inner diameter of 150 mmφ and a depth of 170 mm, placing the sample in a test furnace, melting and solidifying, and then removing the solidified product from the container.

Compared with the comparative examples, the examples show good results in both the flow spreadability represented by the spread area index of the sample and the adhesive shear strength, and the adhesive shear strength is particularly excellent. I understand that.

[0015]

Since the product of the present invention uses diphenyl or (and) diphenylamine as a fluidizing agent, it has excellent fluidity and adhesiveness during hot working, and therefore has good workability.
It was possible to obtain a baked repair material with excellent physical properties. Also,
Since the fluidization aid of the present invention is solid at room temperature without hygroscopicity, it has good storability, and it is possible to obtain a baking repair material excellent in terms of handling including transportation and manufacturing. did it.

[0016]

[Table 1]

Claims (3)

[Claims] 1. A baking repair material comprising a refractory aggregate, a substance that forms a carbon bond during heating as a binder, and diphenyl or (and) diphenylamine as a fluidization aid. 2. As a fluidizing aid, diphenyl or (and) diphenylamine is added in an amount of 0.5 to 40 parts by weight per 100 parts by weight of the refractory aggregate.
Bake repair material described in. 3. As a binder, 5 to 40 parts by weight of a pitch having a softening point of 300 ° C. or less, and diphenyl or (and) diphenylamine are used as the binder to 100 parts by weight of the refractory aggregate.
The baking repair material according to claim 1, wherein 0.5 to 40 parts by weight is blended with respect to 00 parts by weight.