JPH02212355A - Hot furnace reparing binder - Google Patents

Abstract

PURPOSE:To control the porosity formation and cracking of a worked body to be formed on the wall of a furnace and to improve the corrosion resistance of the worked body by adding a small amt. of defoaming agent to the binder for repairing the furnace. CONSTITUTION:The binder for repairing a furnace at high temp. contains 50-5000ppm of a defoaming agent based on the binder. A resin-based binder or a binder contg. the resin-based binder is preferably used as the binder. A phenolic resin is typically used as the resin-based binder, and any of the novolac- type phenolic resin, resol-type phenolic resin, and benzylic ether-type phenolic resin can be used. A silicone-based defoaming agent such as a polymethylsiloxane, a higher alcohol-based defoaming agent, a polyalkylene glycol-based defoaming agent, etc., can be exemplified as the defoaming agent. The silicone-based defoaming agent, which is chemically stable and capable of producing an excellent effect with only a trace amt., is preferably used.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a binder for hot furnace repair materials used in manufacturing repair materials for various furnaces exposed to high temperatures during operation, such as converters. .

[Prior Art] Refractories of furnaces such as converters that house high-temperature molten metal are eroded in various parts depending on the operating conditions of the furnace, resulting in local damage. Furnace repair materials used to repair such damaged parts of furnaces are mainly composed of refractory aggregates such as alumina, magnesia, carborundum, coke, clay, silica, and silica. Aggregate alone cannot be used as a furnace repair material, so a binder is added to give it appropriate plasticity and adhesiveness, and it is kneaded into an appropriate shape so that it can be used depending on the damaged area of the furnace. For example, it is used for spraying, pouring, pouring, etc.

Hot furnace repair materials are used during intervals between furnace operations, and if the repair time becomes longer, the operability of the furnace operation will be reduced. It is required to be applied to damaged parts of furnaces, to have a fast curing speed, and to have excellent high-temperature adhesive properties. The performance of such a hot furnace repair material is largely dependent on the performance of the binder used.

As binders for hot furnace repair materials used for such purposes, there are resin powders such as phenol resin, resin binders made by dissolving such resins in solvents, and pitch binders such as tar and pitch. known (Special Publication No. 59-17, No. 072, Special Publication No. 56-20
．． 329, and Special Publication No. 58-23, 351).

Hot furnace repair materials using such a binder receive heat from the high-temperature part of the furnace wall, melt, harden, and carbonize. The gas generated during carbonization adheres to the furnace wall. In some cases, this may cause cracks to occur in the constructed body, which is a major cause of lowering the corrosion resistance of the constructed body.

[Problems to be Solved by the Invention] As a result of intensive research in view of this point of view, the present inventors have found that by adding a small amount of antifoaming agent to the binder for hot furnace repair material, the formation of foam on the furnace wall. The present inventors have discovered that it is possible to suppress as much as possible the occurrence of porosity and cranking in the constructed body, thereby improving the corrosion resistance of the constructed body, and have thus arrived at the present invention.

Therefore, an object of the present invention is to provide a binder for a hot furnace repair material that can form a construction body formed on a furnace wall with less porosity and cracks, and thereby has excellent corrosion resistance. It is in.

[Means for solving the WR problem] That is, the present invention provides a method for solving the WR problem by adding 50% of the antifoaming agent to the binder.
It is a binder for hot furnace repair material containing in the range of ~5,000 p1)m.

As the binder used in the present invention, a resin binder such as a phenolic resin binder, a pitch binder such as pitch or tar, etc. can be used, but a resin binder or a binder containing a resin binder is preferable. A typical example of this resin binder is a phenol resin, and any of a novolac type phenol resin, a resol type phenol resin, a benzylic ether type phenol resin, etc. can be used.

Such a phenolic resin can be obtained by reacting phenols such as phenol, xylenol, and cresol with formaldehyde in the presence of an acidic catalyst.

In addition, this binder may also contain its own ingredients, if necessary.
Solvents such as tar oil and ethylene glycol, high boiling point tar acids, hexamethylenetetramine, etc. can be added. In particular, examples of the binder of the present invention include those containing phenolic resin or pitch as a main component.

Further, examples of the antifoaming agent used in the present invention include silicone antifoaming agents such as silicone oil such as polymethylsiloxane, higher alcohol antifoaming agents, polyalkylene glycol antifoaming agents, etc. Preferably, it is a silicone antifoaming agent that is chemically stable and exhibits excellent effects even in small amounts.

The amount of antifoaming agent used varies depending on the type of antifoaming agent and the type of binder, but it is
5,000 ppm, preferably 100-3. OOOp
It is pm. 501) I) IIIJ: Very little effect of adding this antifoaming agent was hardly observed, and 5.
Even if the amount is increased more than OOOppm, the effect will not improve much.

When preparing a hot furnace repair material using the binder of the present invention, it may be prepared in advance by blending refractory aggregate, binder, and antifoaming agent in a predetermined ratio and kneading while heating. Alternatively, a binder may be prepared by mixing a binder and an antifoaming agent in advance, and at the time of use, refractory aggregates may be mixed in a predetermined ratio and kneaded under heating. , a binder and an antifoaming agent may be blended in a predetermined ratio at the time of use, and the mixture may be prepared by kneading while heating. In addition, conventionally known fire-resistant aggregates include alumina, magnesia, carborundum, coke, clay, silica, silica, etc. Only one type of these can be used, or a mixture of two or more types can be used. It can also be used as The blending ratio of the refractory aggregate is preferably 75 to 85% by weight based on the total of the binder and the refractory aggregate.

[Examples] The present invention will be specifically described below based on Examples and Comparative Examples.

Examples 1 to 3 and Comparative Example 1 Consists of 5% by weight of novolac type phenolic resin, 25% by weight of benzylic ether type phenolic resin, and 70% by weight of a solvent containing tar oil, pitch, tar acids, and ethylene glycol. To 100 parts by weight of the binder, 1.000 parts by weight of the antifoaming agent shown in Table 1 was added,
Furthermore, 3 parts by weight of hexamine was added as a curing agent and kneaded to prepare a binder.

5g of the obtained binder of each example and comparative example was added to 18#
Take a sample in a tester with a size of 1 Iφ x 165 m, heat it at 200°C using an oil bath to harden it, measure the height before hardening and the height after hardening to determine the height of swelling due to hardening. Ta. The results are shown in Table 1.

Next, 15 parts by weight of the binder obtained in each of the above Examples and Comparative Examples was blended with 100 parts by weight of the refractory aggregate, and
The mixture was kneaded while heating at °C to prepare a lumpy hot furnace repair material.

Regarding the obtained hot furnace repair materials of each example and comparative example,
This was filled into a magnetic crucible with an inner diameter of 30aφ and a height of 150m, and heated from 300℃ to 9℃ at a heating rate of 10℃/min in an electric furnace.
The temperature was raised to 00°C, and the height before curing and the height after curing were measured to determine the height of swelling due to curing. In addition, the surface condition after curing was observed to determine the presence or absence of surface cracks. The results are shown in Table 1.

Table 1 (Note) A: Silicone antifoaming agent (product name manufactured by Toshi Silicon ■: 5C-5570> B: Higher alcohol antifoaming agent (Taiho Awaklin) C: Polyalkylene glycol antifoaming agent (ADEKA) MH-
1000> [Effects of the Invention] By using the binder of the present invention, when repairing the furnace lining, it is possible to suppress as much as possible the formation of porosity and the occurrence of cracks in the construction body formed on the furnace wall. , This can improve the corrosion resistance of the construction body.

Claims (1)

[Claims] (1) A binder for hot furnace repair material characterized by containing an antifoaming agent in a range of 50 to 5,000 ppm; (2) A hot furnace repair material according to claim 1, wherein the antifoaming agent is a silicone oil. Binder for materials.