JPH0331672B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for manufacturing a repair material used for repairing the lining of a furnace. [Prior Art] In kilns such as converters, ladles, and vacuum degassing furnaces used in the steel industry, the lining refractories are locally damaged as the operation progresses. In order to repeatedly use a furnace with damaged lining refractories, it is necessary to repair the damaged parts. Spraying is a commonly used method for this repair. However, since a large amount of water is added during construction, the lining may be damaged due to rapid cooling.
There are drawbacks such as the repair material becoming porous. Furthermore, the adhesive strength is also insufficient. Therefore, a repair material in which a carbonaceous resin such as pitch is added to a fireproof aggregate as a binder has been proposed, for example, in Japanese Patent Publication No. 58-23351. When this repair material is poured into the repaired area while hot, the carbonaceous resin of the binder is heated and melted, and then carbonized, resulting in a repair material structure with excellent spalling resistance and adhesive strength. It becomes strong. [Problems to be Solved by the Invention] However, carbonaceous resin burns in the high-temperature atmosphere inside the furnace, causing significant smoke generation. As a result, the working environment deteriorates. Furthermore, since the carbon component in the carbonaceous resin is easily oxidized, there has been a problem that the effect of carbon bonding cannot be fully exhibited. An object of the present invention is to provide a furnace repair material that solves the problems in the prior art. [Means for Solving the Problems] Therefore, the present inventors first considered suppressing smoke and oxidation of the carbonaceous resin by granulating the conventional repair material to reduce its surface area. However, in order to granulate the mixture, the mixture of refractory aggregate and carbonaceous resin must be heated and kneaded to a temperature equal to or higher than the melting softening point of the carbonaceous resin. During this kneading process, the carbonaceous resin burns, and the problem of smoke still remains. Therefore, when using this method, it becomes difficult to manufacture the repair material. Furthermore, when using large granules obtained in this way, even if heated after being introduced into the area to be repaired, the granules may harden without exhibiting sufficient fluidity. become. Therefore, the formed repair refractory material layer is inferior in density, adhesive strength, etc. However, when an appropriate amount of paraffin was added to the conventional material and the material was granulated under pressure into small pieces, low-temperature heating was sufficient even when heating and kneading, and smoke generation during kneading could be prevented. Furthermore, it has excellent fluidity when heated, and after repair, its compactness and adhesive strength are significantly improved. The present invention
This study was completed based on this knowledge. In order to achieve the objective, the method for producing a repair material of the present invention adds 1 to 20% by weight of paraffin to a compound mainly composed of basic fireproof aggregate and carbonaceous resin, and after kneading, 1 to 20% by weight of paraffin is added. Weight per piece is 10~1000
It is characterized by pressure granulation into small pieces of g. Next, the present invention will be specifically explained. The materials and blending ratios of the basic fireproof aggregate and carbonaceous resin used as the base material in the present invention are as follows:
Not much different from before. As the basic refractory aggregate, one or more selected from magnesia clinker, dolomite clinker, spinel clinker, lime clinker, or brick waste mainly composed of these materials is used. The particle size of this basic refractory aggregate is adjusted so that a densely packed structure can be obtained.
In addition, some of the basic refractory aggregates can be replaced with neutral, acidic refractory aggregates, carbon, carbides, nitrides, slaked lime, limestone,
It can also be replaced with clay etc. On the other hand, carbonaceous resins are organic compounds that turn into carbon when heated to high temperatures, and specifically include bituminous substances such as pitch and coal tar, powders such as phenolic resins, furan resins, epoxy resins, and melamine resins. thermosetting resin, polybdenum resin,
Examples include thermoplastic resins such as vinyl polymers.
One or more selected from these resins,
Used as carbonaceous resin. Among them, Pitch, which has a high residual carbon content (carbonization rate of about 45 to 80% by weight), and phenolic resin (carbonization rate of about 52%)
Favorable results are obtained when using furan resin (carbonization rate of about 49% by weight), etc. The ratio of the refractory aggregate to the carbonaceous resin is preferably 2 to 60% by weight of the carbonaceous resin, with the remainder being the refractory aggregate. If the blending ratio of the carbonaceous resin is less than 2% by weight, the desired carbon connective tissue cannot be obtained. On the other hand, if the blending ratio is too high, the refractory will have poor oxidation resistance. A more preferable range of this blending ratio is:
The carbonaceous resin content is 5 to 40% by weight. The blending ratio of paraffin is 1 to 20% by weight based on the total amount of fireproof aggregate and carbonaceous resin. When the blending ratio of this paraffin is less than 1% by weight,
The strength of the small lump becomes insufficient. On the other hand, if it exceeds 20% by weight, the porosity will increase and the corrosion resistance will be poor. The preferred blending ratio of paraffin is 2 to 15% by weight. Further, known additives for this type of repair material, such as metal powder, fibers, wetting agents, etc., may be added as necessary. These humectants include ethylene glycol, diethylene glycol, propylene glycol, glycerin,
Specific examples include kerosene, anthracene oil, light oil, heavy oil, and lubricating oil. The kneading may be performed by kneading each compound at once, or by kneading while changing the order of addition. An example of the latter case is to knead the refractory aggregate and carbonaceous resin in advance, then add paraffin and knead them again. It is preferable to add paraffin in a heated and molten state. In addition, to improve workability during kneading,
Heat kneading is preferred. In the Examples described below, a briquette machine is used as a means for pressurizing and granulating the mixture thus kneaded into small pieces. This device is equipped with a roller whose surface has a large number of concave holes of a shape and size suitable for small lumps, and the kneaded material is passed through this roller to form small lumps under pressure. , generally known as a charcoal forming machine. The shape of the small lump may be either spherical or polyhedral, but
A sphere or an elliptical sphere is preferred. The size of each small lump is preferably 10 to 1000 g. When this small lump weighs less than 10g, the specific surface area of the entire repair material increases,
It becomes easily oxidized. On the other hand, if it exceeds 1000g, the softening fluidity of the repair material will decrease,
This results in poor filling properties. [Function] In the present invention, as explained above, an appropriate amount of paraffin of a conventional material is added and granulated under pressure into small lumps. By adding paraffin, sufficient kneading can be achieved even by heating at a relatively low temperature, and it is also possible to prevent fuming during kneading. Moreover, the paraffin contained in the repair material is rapidly melted by heating after applying it to the repair area. This makes it possible to obtain a repaired refractory material layer with excellent fluidity and significantly improved density and adhesive strength after repair. That is, even though the repair material is in the form of a lump, it is easily loosened and becomes fluid when it is heated after being put into the area to be repaired. In this way, after flowing and filling the repaired area, the repair material firmly adheres to the object to be repaired due to carbon bonding. And since the repair material is granulated into small lumps,
Its specific surface is small. Therefore, the number of parts that come into contact with the atmosphere is reduced, and smoke, oxidation, etc. are prevented from occurring during repair. [Example] Hereinafter, the effects of the present invention will be specifically explained with reference to Examples. Various repair materials were manufactured using the blending ratios shown in Table 1. At this time, in Examples 1 to 5, the mixture was heated and kneaded at about 50 to 60°C, and then granulated into charcoal shapes each weighing 40 to 50 g using a briquetting machine. In addition, in Comparative Examples 1 and 2, after heating and kneading the mixture at about 100°C, the weight of each piece was 40 to 50% using a briquetting machine.
It was granulated into the shape of charcoal of 100 g. Furthermore, in Comparative Example 3, the mixture was heated and kneaded at about 100 to 110° C., and then the granular material was used as a repair material as it was. Although not shown in Table 1, when each example was heated and kneaded, in Comparative Examples 1 and 2, the pitch was heated to a temperature higher than the melting point of the pitch, so smoke emitted from the pitch was significant, which was not favorable in terms of the working environment. In contrast, in the examples of the present invention, sufficient kneading was possible at a relatively low temperature, and almost no smoke was emitted from the pitch.

【table】

〔Effect of the invention〕

As explained above, in the method for manufacturing a repair material of the present invention, by pressurizing and granulating the repair material to which paraffin has been added into small lumps, smoke generation and oxidation can be suppressed when the repair material is poured into the repaired area. I can do it. After being applied to the area to be repaired, the repair material is easily loosened by the action of paraffin, which has a low melting point.
It melts and flows and fills the area to be repaired. This fluidization is promoted by the paraffin, and the repair material has dense and strong carbon bonds. As a result, the repaired refractory material layer formed with the repair material manufactured according to the present invention has significantly superior durability compared to that formed with the conventional type of repair material.

Claims (1)

[Scope of Claims] 1. Paraffin is added in an outer layer of 1 to 20% by weight to a compound mainly composed of basic fireproof aggregate and carbonaceous resin, and after kneading, small pieces each weighing 10 to 1000 g are prepared. A method for producing a furnace repair material, which is characterized by pressure granulation into lumps. 2. The furnace repair material according to claim 1, wherein the weight of each small lump is 10 to 1000 g.