JPS62197348A - Binder for blast furnace mad material - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a binder used in producing a mat material used during operation or repair of a blast furnace.

[Prior Art] Blast furnace mat materials are used as taphole plugging materials, repair materials, etc. for the operation and repair of blast furnaces. This mat material for blast furnaces is mainly composed of refractory aggregates such as alumina, carborundum, coke, and clay.A binder is added to this to give it appropriate plasticity and adhesiveness, and it is kneaded into an irregular shape. It is an object.

However, since this mat material for blast furnaces is used under the special conditions of a blast furnace, it must have good crosstalk properties, at least enough plasticity to be filled with a mat gun, and hardening after filling. It is required to meet various conditions such as fast speed, good opening properties, no generation of black smoke or abnormal dust, and excellent hot strength and slag corrosion resistance. For this reason, the binder used to manufacture this blast furnace mat material must not only be blended with the refractory aggregate to provide appropriate plasticity and adhesion, but also require strict conditions in various respects. .

From this point of view, we proposed a binder for a mat material for blast furnaces, which is a binder containing a phenolic resin, mixed with high-boiling point tar acid, aromatic hydrocarbon oil, and/or alcohol solvent (Japanese Patent Laid-Open No. 60-51. Publication No. 656).

[Problems to be Solved by the Invention] This binder has a high residual carbon content and has excellent performance in that it provides a cured product with excellent hot strength and corrosion resistance against slag. While offering excellent performance for just N¥1, the binder itself does not change in quality even when heated during transportation, storage, or mat material production, and its viscosity is stable (viscosity stability). The mat material maintains its fluidity without seizing even if it is exposed to high temperatures for a long time (seizure is prevented); ■ Even when the temperature inside the mat gun decreases, the mat material maintains its fluidity and reaches the tap hole. (low-temperature fluidity), and ■ the mat material hardens as quickly as possible in the taphole during extrusion filling (
The present invention provides a binder for a mat material for blast furnaces that has superior performance in terms of rapid hardening.

Means for Solving Problem E] That is, the present invention provides a binder in which a binder containing a phenolic resin is blended with high boiling point tar acid, an aromatic hydrocarbon oil, and/or an alcoholic solvent,
This is a binder for a mat material for blast furnaces that uses a benzylic ether type resol and a novolac type phenol resin in combination as the phenolic resin.

The benzylic ether type resol used in the present invention is
It is obtained by reacting phenols such as phenol, xylenol, and cresol with formaldehyde under the catalyst of divalent metal oxides, hydroxides, or acetates such as Zn, No, and PbCa, and is preferably obtained by reacting formaldehyde with formaldehyde. The molar ratio (F/P) of phenols is 1.05 to 1.
A product manufactured with adjustment within the range of 20 is used. By adjusting the molar ratio (F/P) to a range of 1.05 to 1.20 during production, there is an advantage that thermal stability at around 100° C. is improved. In addition, this benzylic ether type resol has a temperature higher than 100°C compared to normal resols.
It has good thermal stability before and after extrusion filling, and shows high reactivity at around 200℃, so the viscosity does not increase significantly during the process from mat gun to extrusion filling, and it hardens quickly after extrusion filling. It has this effect.

Further, the novolac type phenol resin used in combination with this benzylic ether type resol is obtained by reacting phenols such as phenol, xylenol, and cresol with formaldehyde in the presence of a m-functional catalyst, and is preferably a liquid. It has a molecular weight of 500 or more as measured by the O-madograph method. By using a novolac type phenolic resin having a molecular weight of 1500 or more, the viscosity of the binder can be maintained at an appropriate value. This novolac type phenol resin is used as a binder component like the benzylic ether type resol, but the high molecular weight one also functions as a viscosity modifier.

The ratio of the benzylic ether type resol and novolac type phenol resin used is usually 40:
60-80:20, preferably 50:50-70
: The range is 30. If the amount of benzylic ether type resol used as a phenolic resin is less than 40% by weight, a problem arises in that the viscosity increases significantly at around 100°C, and if it exceeds 80% by weight, the viscosity decreases so much that it is not practical as a binder. The problem arises that it is not.

In the present invention, high boiling point tar acid, an aromatic hydrocarbon oil, and/or an alcoholic solvent are blended into a binder containing a phenolic resin consisting of the benzylic ether type resol and novolak type phenolic resin.

The high boiling point tar acid used here is usually obtained by distillation of crude tar acid obtained by extraction and separation from tar oil.
Tar acid is obtained by separating a fraction with a boiling point of 00°C or lower, preferably a boiling point of 250°C or lower. This high-boiling tar acid has a boiling point of 200° C. or higher and may contain pitch produced during distillation. This high boiling point tar acid exhibits a high residual carbon content similar to phenolic resin, has excellent compatibility with phenolic resin, and when used as a mat material, reacts with phenolic resin to form strong carbon bonds.
Improves the strength of cured products.

Furthermore, the aromatic hydrocarbon oil used in the present invention is a hydrocarbon consisting of alkylbenzenes, naphthalenes, alkylnaphthalenes, anthracenes, biphenyls, dibenzofurans, fluorenes, phenanthrenes, etc., or one thereof.
A hydrocarbon oil consisting of two or more species, such as tar oil obtained by distilling coal tar or a neutral oil obtained by refining this, usually containing methylnaphthalene and dimethylnaphthalene as the main components. boiling point range 185
~370°C is preferred. If the boiling point of the aromatic hydrocarbon oil is low, the aromatic hydrocarbon oil will volatilize after the mat material is prepared, and the plasticity of the prepared mat material will change easily, which will not only hinder the filling operation with a mat gun, but also cause problems after filling. Rapid evaporation tends to cause cracks and cavities in the structure of the mat material. In addition, if the boiling point of the aromatic hydrocarbon oil is too high, it will remain in the structure of the hardened mat material, and this will decompose during the heating process of the mat material, destroying the structure of the mat material and causing a decrease in corrosion resistance. This may cause problems such as: This aromatic hydrocarbon oil exhibits excellent compatibility with high-boiling tar acid and reduces the viscosity of high-boiling tar acid, so it is used alone or together with an alcoholic solvent as a solvent or viscosity modifier.

The alcoholic solvents mentioned above include ethylene glycol,
Glycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, hexylene glycol, glycerin such as gutserin, siglycerin, monoalcohols such as methanol, octyl alcohol, nonyl alcohol, etc. can be mentioned. This alcohol-based solvent has a relatively high boiling point, and
Those with a high flash point are preferred. This alcoholic solvent exhibits excellent solubility for phenolic resins.

In the present invention, the blending ratio of the phenolic resin consisting of benzylic ether type resol and novolac type phenolic resin, high boiling point tar acid, aromatic hydrocarbon oil and/or alcoholic solvent is 5 to 70%.
The heavy suspended part is preferably 15 to 50 parts by weight, more preferably 20 to 40 parts by weight, and the high boiling point tar acid is 10 to 60 parts by weight.
parts by weight, preferably 15 to 50 parts by weight, more preferably 20 to 40 parts by weight, and the aromatic hydrocarbon oil is 0 to 40 parts by weight.
parts by weight, preferably 5 to 30 parts by weight, more preferably 1
0 to 25 parts by weight, and the alcohol solvent is 0 to 30 parts by weight.
im part, preferably 5 to 25 parts by weight, more preferably 5
~20 parts by weight, the total of the aromatic hydrocarbon oil and alcoholic solvent is 10 to 50 parts by weight, preferably 20 parts by weight.
~40fffffi portion. If the blending ratio of phenolic resin is too small, the residual carbon content will decrease and the hot strength will deteriorate, and the initial curing time will also become long; on the other hand, if it is too large,
Not only does the viscosity become too high, but the degree of performance improvement also decreases.

Regarding high-boiling point tar acid, if its blending ratio is small,
The residual carbon content decreases and the hot strength deteriorates, and on the other hand, if it is too much, the viscosity becomes too high. Regarding aromatic hydrocarbon oils and alcoholic solvents, if the total amount used is small, the solubility in high boiling point tar acid and phenolic resin will decrease, and on the other hand, if the amount used is too large, the residual carbon rate will decrease. descend. These aromatic hydrocarbon oils and alcoholic solvents may be used alone, but aromatic hydrocarbon oils are compatible with high boiling point tar acid, and alcoholic solvents are compatible with phenolic resins. Because it is excellent
If these two are used together, the compatibility with both high boiling point tar acid and aromatic hydrocarbon oil will be improved.

When preparing the binder of the present invention, a phenolic resin consisting of a benzylic ether type resol and a novolak type phenolic resin, high boiling point tar acid, and an aromatic hydrocarbon oil and/or an alcoholic solvent are mixed in a predetermined ratio. Just mix and dissolve uniformly.

Furthermore, the binder of the present invention can be used in the same manner as conventionally known binders. That is, when preparing a mat material for a blast furnace, it is sufficient to mix it with an appropriate refractory aggregate at a certain ratio and knead it.

As this refractory aggregate, a wide range of conventionally known materials can be mentioned, specifically alumina, carborundum,
Examples include coke, clay, and a combination of two or more of these. The blending ratio of these refractory aggregates and binder is such that the binder is usually 10 to 40 parts by weight, preferably 15 to 25 parts by weight, per 100 parts by weight of the refractory aggregate.

In the present invention, when preparing a binder or when preparing a mat material for a blast furnace using this, hexamethylenetetramine or the like is used as a curing agent for a novolak type phenolic resin. Since the benzylic ether type resol is used together with the type phenolic resin, the amount of curing agent used is reduced accordingly, the curing effect at low temperatures is suppressed, and the thermal stability at around 100°C is further improved.

[Example 1] Hereinafter, the present invention will be specifically explained based on an example and a comparative example.

Examples 1 to 5 and Comparative Examples 1 to 3 Benzylic obtained by adjusting the molar ratio (F/P) of formaldehyde and phenols to 1.1 and reacting at 100°C for 4 hours using zinc acetate as a catalyst. An ether type resol was used, and novolac type phenol resins having the molecular weights shown in Table 1 (measured by liquid chromatography) were used.

The above-mentioned benzylic ether type resol, novolak, high boiling point tar acid of 220° C. or higher, aromatic hydrocarbon oil containing methylnaphthalene and dimethylnaphthalene as main components, and ethylene glycol as an alcoholic solvent are first added. They were blended in the proportions shown in the table, mixed under stirring, and hexamethylenetetramine in the amount shown in Table 1 was added and dissolved to prepare binders for each example and comparative example. For each of these binders, the viscosity, gel time at 200°C, residual carbon percentage, and viscosity change over time at 90°C were measured. The results are shown in Table 1.

The gel time was measured by taking 5 g of the sample into a test tube, heating it in an oil bath at 200° C., measuring the time until the content lost fluidity, and defining this time as the gel time. In addition, regarding the residual carbon percentage, a sample of 2g was taken into a crucible, weighed, and then baked in an electric furnace at 750°C for about 7 minutes with a lid on.
The residue was weighed and its heavy R ratio was defined as the residual carbon percentage.

Next, using each binder of Example 5 and Comparative Example 3,
21 parts by weight of each of the binders mentioned above is mixed and kneaded with 100 parts by weight of fireproof aggregate mainly composed of fireclay and coke powder to form a mat material for blast furnaces w4! ! It was. Each of the obtained mat materials was heated at 110° C., and the mat hardness was measured at an extrusion speed of 15 Im/Win after 1 hour and 5 hours of heating time. Further, these mat materials were cured at 900° C. in a nitrogen stream, and the resulting cured products were subjected to a hot bending test and a corrosion resistance test. The results are shown in Table 2.

Table 2 Furthermore, an actual furnace test was conducted in a blast furnace for the blast furnace mat material using the binder of Example 5 and the blast furnace mat 44 (tar mat) using coal tar as a binder control. The results are shown in Table 3.

Table 3 The mat material using the binder of Example 5 had a larger tap hole depth and was better than the tar mat material using coal tar as the binder, and both the unfilling rate and the burned mat were O. It is better than tar mat, and the mat temperature in the mat gun is 45-7
It only needs to be kept at 5℃, so it can be heated to 100℃ like tar mat.
There is no need to raise the temperature above ℃, and there is little smoke generation, and the L: & development property is good.

[Effects of the Invention] The binder of the mat material for blast furnaces of the present invention has a high residual carbon content similar to the binder using only novolak type phenolic resin as the phenolic resin, and has excellent hot strength, corrosion resistance against slag, and tap hole. Not only does it provide a cured product with excellent depth, pore size expansion tendency after the start of slag flow, stability of the blocked state, smoke generation, and mat material consumption, but it also has excellent viscosity stability, anti-seizure properties, low-temperature fluidity, and quickness. B exhibits a more layered performance in terms of hardness.

Patent applicant: Nippon Steel Corporation e Co., Ltd. Same as above
Nippon Steel Chemical Co., Ltd. Harima Fire Brick Co., Ltd. Representative Patent Attorney Katsuo Naruse (2 others)

Claims (4)

[Claims] (1) In a binder formed by blending high-boiling point tar acid, aromatic hydrocarbon oil and/or alcohol solvent into a binder containing a phenolic resin, a benzylic ether type resol and a novolac type phenolic resin are used as the phenolic resin. A binder for mat material for blast furnaces, which is characterized by the combination of (2) Benzylic ether type resol has a formaldehyde to phenol molar ratio (F/P) of 1.05 to 1.
．． The binder for a mat material for a blast furnace according to claim 1, which is manufactured by adjusting the binder content within the range of 20. (3) The binder for a mat material for blast furnaces according to claim 1, wherein the novolac type phenolic resin has a molecular weight of 500 or more. (4) The weight ratio of benzylic ether type resol and novolac type phenol resin is 40:60 to 80:
20. The binder for a mat material for a blast furnace according to any one of claims 1 to 3.