KR940007267B1 - Process for the preparation of dolomite-stamp - Google Patents

Abstract

The process comprises the steps of adding 2.8-9.3 wt.% of liquid petroleum resin to 65.1-83.7 wt.% of crude or medium particles of dolomite clinker and magnesia clinker and kneading; adding 0.9-4.7 wt.% of petroleum type pitch powder thereto and coating thereof; and kneading with the addition of 9.9-27.9 wt.% of microparticles of magnesia clinker.

Description

Manufacturing method of dolomite stamping material

1 is a manufacturing process diagram according to the present invention

The present invention relates to a method for producing a dolomite stamp, and more particularly, to a method for producing a dolomite stamp material having improved novel binders, kneading methods and other formulation properties.

In recent years, when building refractory materials in various furnaces, such as converters and refining furnaces, stamp materials used by filling and filling with air rammers or other parts between orthogonal refractory materials that cannot be regenerated or around and bottom of the furnace are used. In this case, calcia-like clinkers such as dolomite clinker and lime clinker have excellent corrosion resistance to basic slug and the like, and thus have been used as raw materials for form and refractory materials as well as their raw materials.

However, since the calcined clinker reacts with moisture to produce a hydrate, the calciner has a drawback of changing its quality characteristics not only in orthogonal refractory, but also in order to prevent various water and waterproofing binders. I use it.

In general, the main properties required for the production of dolomite amorphous refractory and its preparation, in addition to the fire resistance described above, preservation of uncured and the like after kneading, construction properties such as good filling, corrosion resistance and manufacturing workability, environmental hygiene and the like in molten steel and slugs, etc. There is this.

Conventionally, singular and amorphous refractory materials having tar and pitch as binders have been commonly used as water-resistant binders. However, alcohols, synthetic resins, etc. have been recently used due to problems such as manufacturing workability of heating and kneading and environmental sanitation of harmful substances. The use of binders is on the rise.

In particular, a method of adding a phenol resin modified by one or a mixture of alkylene carbonates with phenols or a binder modified therefrom (Japanese Patent Laid-Open No. 60-26065) and alkylbenzene as a non-aqueous liquid binder for refractory materials Non-aqueous solvent of calcia-like amorphous refractories (JP-A-60-22943) added with modified phenolic resins, refractory compositions (JP-A--50-100110) mixed with a thermosetting resin and a thermoplastic resin, and a polyhydric alcohol As for example, the converter stamp material (Patent No. 51-105315) using the polyglycerol by-produced at the time of glycerin manufacture is proposed.

However, among these conventional methods, in the converter stapling material using the polyglycerol which is closest to the present invention, there is a problem in that the preservation, workability, manufacturing workability and environmental hygiene are deteriorated.

Accordingly, an object of the present invention is to provide a method for producing a dolomite stamping material, which is the same or improved in corrosion resistance than the stamping material using a conventional polyglycerol, and excellent in storage properties, workability, manufacturing workability and environmental hygiene.

In order to achieve the above object, the present invention proposes a method for preparing a dolomite stamp in which a basic refractory is prepared by adding a liquid petroleum resin and a powder pitch to aggregates such as dolomite, which are digestible.

Therefore, according to the present invention, after mixing at room temperature with a non-aqueous liquid binder in order to prevent digestion of calcias such as dolomite clinker, lime clinker and the like, and improve the corrosion resistance such as hot strength and slug, Provided is a method for producing a dolomite stamp material which is prepared by dissolving and adding a double coatable powdery pitch and kneading in two stages so as to coat the binder with the binder.

Hereinafter, the present invention will be described in detail.

In FIG. 1, the method for producing a dolomite stamping material according to the present invention has a good kneading coating property of the refractory raw material particles during kneading, and uses 65.1 to 83.7% by weight of raw materials to prevent quality fluctuation or abnormal erosion during construction. 2.8 to 9.3% by weight of liquid petroleum resin is added to raw materials including granular or more digestible aggregates, and kneaded at room temperature, and then coated with 0.9 to 4.7% by weight of petroleum pitch powder as a carbon source. To 27.9% by weight of the final product is prepared.

In the present specification, in the refractory raw material particles, granulation is defined as particles having a particle size of 3 to 5 mm, particles having a particle size of 0,074 to 3 mm, and particles having particles having a particle size of 0 001 to 0.074 mm.

If refractory raw material assembly, intermediate and fine grains are not kneaded in two stages, the amount of liquid petroleum resin increases and becomes expensive, as well as the non-aqueous system for coarse and neutral granules containing digestible aggregates by mixing fine and liquid petroleum resins. Poor coating of liquid petroleum resin

When the amount of the liquid petroleum resin is added in an amount of 2.8% by weight or less, the adhesiveness and fluidity are lowered and the workability is decreased. When the amount of the liquid petroleum resin is increased by 9.3% by weight or more, the product is not only expensive, but also the viscosity is increased, so that the storage property and workability are decreased.

As liquid petroleum resin of the present invention, a high boiling point hydrocarbon solvent is added to a resin copolymerized with styrene, vinyl tolune, indene, etc. This is a non-aqueous liquid petroleum resin adjusted to 3 to 10 Poise, which is a very small amount of 0.07% by weight or less and a viscosity at which room temperature coating is easily applied to the extinguishing aggregate.

This completely overcomes the problems of preservation and workability of the product by hot kneading coating and curing after kneading by using a conventional high viscosity binder.

In addition, since the binding material is a binder of styrene, indene and vinyl toluene, which are carbon- and hydrogen-only bonds, not a binder having its own hydroxyl group bond such as phenolic resin, stability and hot fire resistance at the time of manufacture are extremely excellent.

However, when the viscosity of the liquid petroleum resin is less than 3 Poise, not only the corrosion resistance and the strength decrease, but also the pitch powder dissolution reaction increases as the amount of the high boiling point hydrocarbon solvent added to the resin increases, thereby increasing the amount of the pitch powder, which is a carbon source. In addition, when it is more than 10 Poies, not only is room temperature kneading difficult due to the increase of the viscosity of the winter season, but also it interferes with the carbon bonds when decomposing the petroleum resin in the product at high temperature, resulting in corrosion resistance and strength reduction.

As the pitch powder used as the carbon source according to the present invention, a powder processed to 70% or more of fixed carbon from which noxious impurities are removed and a particle size of 0.105 mm or less is 98% or more is used. This pitch powder is dissolved by the high boiling point hydrocarbon solvent added to the liquid petroleum resin in the production of basic amorphous refractory material and double coated on the liquid petroleum resin coated on the digestible aggregate to provide excellent fire resistance, workability and flexibility of the product. It not only plays an excellent role in the preservation of uncured, etc., but also complements the liquid petroleum resin binder with a low residual coal ratio to form carbon bonds of aggregates in the hot, improving hot strength and corrosion resistance.

However, in the case of the addition amount of the pitch powder, the molten steel and the slug permeation is increased when added to 0.9% by weight or less, and the corrosion resistance of the product is lowered.

A more specific example of this invention and the converter stamp material (patent place 51-105315) using the conventional polyglycerol are demonstrated as a comparative example. In addition, this invention is not limited by the Example.

EXAMPLE

As shown in Table 1 by the production process of FIG. After kneading for 5 minutes by adding weight%, after adding 2.3 wt% of pitch powder, kneading for 5 minutes, 23.3 wt% of magnesia clinker fine particles (0.074mm or less) were added, and the mixture kneaded for 5 minutes was left for 3 months. Press molding at 40 × 40 × 160mm and molding pressure 200kg / cm ² to measure volume specific gravity, compressive strength and bending strength at 500˚C and 1400˚C for 2 hours (KSL3503) and 300g mixture 50ψmm × 150kg / After pressurizing to cm ² , the weight of the specimen divided by the filled volume is used as the filling rate.In order to measure the corrosion resistance of the slug, the specimen is placed in a rotary drum erosion machine and the converter slug is put at 1700˚C for 2 hours before the test. Psalter The erosion length withstand length was measured and the result is shown in the 2nd table | surface.

[Comparative Example]

As shown in [Table 1] by the manufacturing process of FIG. 1, polyglycerol produced by the production of glycerin was kneaded by mixing a granulated / medium granule (0.074-5 mm) dolomite clinker with 74.5% by weight of magnesia clinker in a mixer for 3 minutes. After adjusting to 4Poise of aggregate and coating viscosity at 100˚C, 4.6% by weight was added for 5 minutes, 2.3% by weight of pitch powder was added, followed by 5 minutes of kneading to finally magnesia clinker fine particles (0.074mm or less). ) After 3 months of mixing the mixture kneaded for 5 minutes with 18.6% by weight, press molding at 40 × 40 × 160mm and molding pressure 200kg / cm ² to increase the specific gravity, compressive strength and bending strength to 500˚C and 1400˚C. Measured for 2 hours each, 300g of the mixture was pressurized to 50mm ψ 150kg / cm ² and the weight of the specimen divided by the filled volume as the filling rate, and also measured in a rotary drum erosion to measure the corrosion resistance to slug After putting on the converter slug at 1700˚C after the two-piece mounting, after measuring the erosion length to the test specimen length before the test for 2 hours, the results are shown in [Table 2].

TABLE 1

As a result of measuring the Examples and Comparative Examples according to the present invention as shown in Table 2 in Table 1, the volume specific gravity (500 ° C × 2 hours, 1400 ° C × 2 hours) is 2.65 and 2.59 in the present invention, respectively In the comparative example, 2.56 and 2.54, respectively. Compared to the comparative example of the present invention, it can be seen that the volume specific gravity is improved by 3.5% and 1.6%.

Compressive strength (500˚C × 2 hours, 1400˚C × 2 hours) was 65kg / cm ² and 38kg / cm ² in the present invention, respectively, 42kg / cm ² and 34kg / cm ² in the comparative example . Compared with the comparative example of the present invention, it can be seen that the compressive strength is improved by 54.8% and 11.8%.

The flexural strength (500˚C × 2 hours, 1400˚C × 2 hours) was 24kg / cm ² and 17kg / cm ² in the present invention, respectively, and 22kg / cm ² and 15kg / cm ² in the comparative example, respectively. Compared with the comparative example of the present invention, it can be seen that the bending strength is improved by 9.1% and 13.3%.

The filling rate was 2.82 in the present invention, and 2.73 in the comparative example. Compared to the comparative example of the present invention, the filling rate was improved by 3.3%, and the erosion length (1700 ° C × 2 hours) was found to be 5.6 mm in the present invention, and 9.4 mm in the comparative example. Compared to the comparative example, the present invention shows that the erosion length was improved by reducing 40.4%.

Claims (1)

65.1 Assembling and kneading by mixing 83.7% by weight of the dolomite clinker and magnesia clinker with 2.8 to 9.3% by weight of liquid petroleum resin, and by adding 0.9 to 4.7% by weight of petroleum pitch powder And 9.3 to 27.9% by weight of fine particles of magnesia clinker, followed by kneading to prepare the dolomite stamping material.