JPS60246257A - Manufacture of refractory brick - 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 (Field of Industrial Application) The present invention relates to a method for producing fireproof bricks, including, but not limited to, fireproof bricks used for lining blast furnaces, converters, electric furnaces, etc. Concerning the manufacturing method of bricks.

[Prior art]

Blast furnaces, converters, electric furnaces, and other ceramic furnaces used for refining metals such as iron and aluminum are used under harsh conditions at high temperatures, so the inner walls of the furnaces are made of fireproof bricks. is lined inside. Various types of refractory bricks are known, such as magnesia-carbon bricks, alumina-carbon bricks, and carbonaceous bricks, but these bricks have excellent hot strength and slag resistance. In both cases, aggregates made of fire-resistant materials or carbon materials are mixed with a binder and formed into a predetermined shape.
It is manufactured by Tl.

In addition, the binders used when making these refractory bricks include pitch-based binders such as right-handed pitch and b-charcoal-based pip, and phenolic resin-based binders such as phenolic resin and furan-modified phenolic resin. Are known. Incidentally, pitch-based binders are easier to graphitize than phenolic resin-based binders, and when comparing binders alone, pitch-based binders are superior to phenolic resin-based ones, but pitch-based binders In addition to the disadvantages of poor workability during brick manufacturing, such as the need for heating cross-wires and poor filling properties during molding, brick physical properties deteriorate due to expansion immediately after heat treatment, and the brick performance is 71. The results are inferior to bricks using a knoll resin binder. For this reason, recently, phenolic resins have become mainstream as binders for carbon-containing bricks.

However, recent regulations for the use of steel windows are becoming increasingly strict, and the durability of phenolic resin binders is beginning to show its limits, and the excellent performance of pitch binders is becoming increasingly difficult. There is no one.

Therefore, in consideration of such problems, we have created a firebrick using a mixed binder that combines pip-based and phenol-based materials in a predetermined ratio (by combining them, we can combine the advantages of both). However, even when this mixed binder is used, it does not satisfy any of (a) in terms of various physical properties such as residual emissivity after firing and viscosity-dependent crosstalk. Therefore, there is a need to develop a method for manufacturing refractory bricks that has even better physical properties.

[Purpose of the invention]

The present invention has been devised in view of the above-mentioned viewpoints.The purpose of the present invention is to not only make it possible to produce a refractory brick with high hot strength and excellent corrosion resistance tQ, but also to make it possible to The object of the present invention is to provide a method for producing firebricks that have a fast curing speed and excellent moldability.

[Structure of the invention]

That is, the present invention uses magnesia clinker-50 to 9
0Φ wrinkle part, carbon material 10~50 heavy part and metal 0~10
15 to 65 weight % of phenolic resin and 50 weight η% of purified PIDEF per 100 weight parts of aggregate constructed in Φ Kawabe.
After blending 2 to 10 parts by weight of a binder containing 18 to 44% by weight of boiling point phenols and having a combined ratio of these three components of 60% by weight, and mixing uniformly. This is a method for producing firebricks that is pressure molded and heat cured at 200 to 400°C.

As the aggregate used in the present invention, known aggregates such as magnesia-carbon type, which are excellent in wear resistance and have a long life, can be used. Magnesia includes magnesia clinker, and carbon (carbon) includes earthy graphite, natural graphite, artificial graphite, electricity scrap, petroleum coke, foundry coke, carbon black, pitch coke, etc. The clinker and the carbon material are such that the former is in the 50-90 m section and the latter is 10-50 parts by weight, preferably the former is in the 60-80 gutter section and the latter is in the 15-35 gutter section. Manoko, the metals added to these ngnesia clinkers and carbon materials include:
Any material may be used as long as it can become an oxide and absorb oxygen, such as aluminum or zinc. The mixing ratio of this metal (1, usually 0 to 10 parts by weight, preferably 3 to 5 parts by weight).

The phenolic resin used in preparing the binder in the present invention is a thermoplastic novolac type phenol made into a resin by reacting phenols such as J-nor, t-cresol, and cresol with formaldehyde in the presence of an acidic catalyst. When the resin is used to mold firebricks,
Thermosetting resol-type phenolic resins, which are cured by reacting phenols with formaldehyde in the presence of a basic catalyst, can also be used; naphthalene, furan, etc. It may also be a modified phenolic resin modified with rosin, lignin, fatty acid, drying oil, or the like. This phenolic resin has a high residual elongation rate when producing firebricks.

6- In addition, even if the refined pitch constituting the binder is right-handed or coal-based, the Q
However, those with high aromaticity are preferred. This refined pitch uses any hydrocarbon, for example, coal tar, crude oil, oak 1J, etc. obtained during the production of =1-x, as a raw material, and is purified by means such as distillation or heat treatment. Pitch is classified into soft pitch with a softening point of 70°C or lower, medium pitch with a softening point of 70 to 85°C, and hard pitch with a softening point of 85°C or higher, but preferably soft pitch or medium pitch. It is. Furthermore, these pitches usually contain about 5 to 15% of the quinolinated content, but if this quinolinated content exists at many ends, the dispersibility will be affected when used as a binder for refractory bricks. This will have an adverse effect on l'J, and will also have an adverse effect on the storage stability of Preferably, it is separated and removed to 0.1% or less.This refined pitch not only has a high residual carbon content when producing refractory bricks, but also exhibits excellent binder properties.

Examples of the 111-bodied alcohols used with the above purified pitch include cresols, 2,3-xylenol, 2.
Examples include xylenol such as 4-xylenol, 2.5-xylenol, and 2.6-xylenol, i-limable phenols such as 2.4.6-drimethylphenol, ethylphenols, and methyl/ethylphenols. be able to. This high boiling point phenol may be the compound of A-1 or a mixture containing two or more compounds, for example, high boiling point tar acid obtained by distilling tar acid. Good, but preferably 2.4-
It is a xylenol soluble component. . These high-boiling point phenols also do not show a high residual carbon content like the above-mentioned phenolic resins and purified pitches, and also show excellent compatibility with both phenolic resins and purified pitches, and when producing firebrick,
Reacts with Knoll resin to create strong carbon bonds and improves the strength of refractory bricks.

In the present invention, in addition to each of the binder components described above, other components such as high-boiling aromatic hydrocarbon oil, alcoholic solvent, water, surfactant, etc. may be blended for the purpose of improving compatibility and reducing viscosity. I can do it.

The high-boiling aromatic hydrogenated oil used for this purpose includes hydrocarbons such as alkylbenzenes, naphthalenes, al-4-lupphthalenes, anthracenes, biphenyls, dibenzofurans, fluorenes, and phenane-1-lenes. From one or more types of oil <7. Among them, hydrocarbon oils such as fluorine and chlorine are preferred.

Examples of such soluble components include tar oil obtained by distilling tartar or neutral oil obtained by refining this, with a boiling point range of 185 to 370°C. Also,
Examples of alcohol-based solvents include glyfurs such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dibu[]pyrene glycol, and hexylene glycol, glycerins such as glycerin and diglycerin, and methanol. , octyl alcohol, nonyl alcohol and the like.

Although the above-mentioned high-boiling aromatic hydrocarbon oil is lipophilic, it exhibits excellent compatibility f1 with phenolic resins, refined bids, and high-boiling phenols. In addition to showing excellent solubility in the binder, it also shows affinity for the aggregate during the preparation of firebrick compositions and improves the compatibility between the binder and the aggregate. Furthermore, water has excellent affinity for both phenolic resin and aggregate, and surfactants contribute to the dispersion stability of the binder composition and improve the affinity of the binder composition with aggregate. let

Regarding the blending ratio of phenol resin, purified pitch, and high boiling point phenols when preparing the binder of the firebrick composition, the phenol resin is 15 to 65% by weight, preferably 20 to 60% by weight, more preferably 3% by weight.
0 to 50% by weight, purified pitch is 7 to 50% by weight,
Preferably the content is 810-40% by weight, more preferably 10-20% by weight, and the content of high-boiling phenols is 18-44% by weight, preferably 20-40% by weight, and the combined resistance of these three components is It is 60% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more. Regarding phenolic resin, if the blending ratio is small, the residual carbon content will decrease and the hot strength will deteriorate, and the gel time will also be improved, but if it is too large, the viscosity will increase, and even if it is added above a certain amount, the fire resistance will deteriorate. The degree of improvement in the physical properties of bricks decreases. Regarding refined pitch, if the blending ratio is too low, the residual carbon content will decrease and the physical properties of the refractory brick will not be improved, while if it is too large, the viscosity will increase and the gel time will become longer. Furthermore, high boiling point phenols not only improve the compatibility of the phenolic resin and purified pitch, but also contribute to the residual carbon content by reacting with hexamethylenetetramine used as a hardening agent. Compatibility with the material decreases.

In addition, when the above-mentioned high-boiling aromatic hydrocarbon oil, alcoholic solvent, water and surfactant are blended, the blending ratio is usually 1 to 5% for high-boiling aromatic hydrocarbon oil. , preferably 2 to /I width%, for alcoholic solvents it is usually 5 to 20% by weight, preferably 7 to 15% by weight, and for water usually 1 to 5% by weight, preferably 2% by weight. -4% by weight, and for surfactants, it is usually 0.5-5% by weight, preferably 1-4% by weight.
It is m%. These high-boiling aromatic hydrocarbon oils, alcohol-based solvents, water, and surfactants are used to improve the viscosity and dispersibility when preparing the binder, or when manufacturing firebricks. Considering the residual carbon percentage and gel time, etc., add as appropriate within the specified range.

When producing a refractory brick in the present invention, first, the above-mentioned phenolic resin, purified bidi and high-boiling phenols, or in addition to these, the above-mentioned high-boiling aromatic hydrocarbon oil,
A binder is prepared by blending an alcoholic solvent, water, and a surfactant in a predetermined ratio and uniformly dissolving it, and then mixing it into an aggregate made by blending magnesia clinker 12-, a carbon material, and a metal in a predetermined ratio. The binder may be blended in a predetermined ratio to uniformly generate cross-wires. When making this firebrick composition by WA, the mixing ratio of the above aggregate and binder is 100% of the aggregate.
The amount of binder is usually 2 to 10 times 4 to the ffiffi part.
parts, preferably 3 to 6 parts by weight.

Further, the composition prepared in this way is mixed uniformly by a mixer such as a lower mixer or a kneader, and then is mixed at a pressure of 0.1 to 5 j/tri by a pressure machine such as a hydraulic press or a friction press. 1 to 10 to 5
It is pressurized and tightened 0 times, and further, after drying, it is 200 to 40
It is treated at a temperature of 0°C and the amount of hardening increases.

In addition, in the present invention, when a novolak type phenol resin is used as the phenol resin, hexamethylenetetramine or the like is blended as a hardening agent when manufacturing the firebrick.

〔Example〕

Hereinafter, based on Examples and Comparative Examples, 13- The manufacturing method of firebrick will be specifically explained.

Examples 1 to 4 and Comparative Examples 1 to 3 Novolac type phenolic resin (
Formalin/phenol molar ratio 0.7), purified pitch (softening point 36°C, quinoline solubility 0°02%), high-boiling phenols mainly containing 2,4-xylenol with a boiling point of 200 to 215°C. Aromatic hydrocarbon oil (boiling point 2
50° C. or higher), ethylene glycol, water, and a surfactant, and mixed uniformly with stirring at room temperature to prepare a binder composition.

Next, magnesia clinker (particle size 5 to 1 m) was used as aggregate.
62.5%, 1~0.2#M118.75% and U0.2
JW (18.75% or less) 77 parts of tim, 20 parts of natural graphite and 5 parts of metal aluminum were used, and the binders of Examples 1 to 4 and the compositions are shown in Table 2. At the same time, 15% by weight of hexamethylenetetramine was added to the binder composition on an outer layer, and the mixture was mixed at room temperature with a 14-Mikili at a pressure of 180 (1 F/Ci). Face/14
It was made into a size of 0 #I and heat treated at 350° C. for 48 hours to harden it and obtain a refractory brick. In addition, as Comparative Examples 1 and 2, a phenolic resin binder made from petroleum pitch, which has been conventionally used (Comparative Example 1: non-volatile content 6
3.0% by weight, fixed carbon 40% by weight; Comparative Example 2: nonvolatile content 73.0% by weight, fixed carbon 44% by weight; Comparative Example 3 also used a phenolic resin binder (nonvolatile content 68% A refractory brick was obtained in the same manner as in the binder composition of Example 1 using . IC using the binders of each of the above examples and comparative examples.
Regarding refractory bricks, physical properties of the cured product and 1000℃
The physical properties after reduction firing were investigated. The results are shown in Table 2. The corrosion test was evaluated using a four-stage evaluation method: corrosion, good, fair, and poor.

15- As is clear from Table 2, the refractory bricks of Examples 1 to 4 have superior performance, especially in the hot oil strength and oil immersion tests after reduction firing, compared to the refractory bricks of Comparative Examples 1 to 3. It was found that it shows.

[Efficacy of invention Song Dynasty]

The method for producing firebricks of the present invention not only makes it possible to produce firebricks with a high residual carbon content of the binder used and excellent hot strength and corrosion resistance, but also improves the kneading process during the production of firebricks. This significantly improves the workability of molding and molding.

Patent applicant: Kurosaki Ceramics Co., Ltd. Nippon Steel Chemical Co., Ltd. Agent: Ben Sokushi Masaru Naruse Same as Tomohiro Nakamura 17- 342-

Claims (4)

[Claims] (1) 15 parts by weight of phenolic resin per 100 parts by weight of aggregate composed of 50 to 9011 parts of magnesia clinker, 11110 to 50 parts by weight of carbon material, and 0 to 10 parts by weight of metal.
65% by weight, purified pitch 7-50% by weight, and high-boiling phenols 18-44% by weight, and the total of these three components is 60% by weight or more.
A method for producing a firebrick, which comprises blending the ingredients in an amount within a range of 0 parts by weight, mixing uniformly, press-molding, and heat curing at 200 to 400°C. (2) The method for producing a firebrick according to claim 1, wherein the phenolic resin is a novolac type phenolic resin. (3) Claim 1, in which the purified pitch is a soft pitch with a softening point of 70°C or less obtained by separating and removing quinolinous components.
2. A method for producing a refractory brick according to paragraph 2 or paragraph 2. (4) The refractory brick according to claim 1r14 or 3rd JFi, wherein the high-boiling phenol is 2,4-xylenol distillate! ii Construction method.