JPS6042190B2 - Refractory material for blast furnace tapping - Google Patents

Description

[Detailed description of the invention] The present invention mainly relates to a refractory material for tapping associated with a blast furnace,
Pyrophyllite (Pyr
It is characterized by the use of carbon-containing waxite (ohillite).

This pyrophyllite carbon-containing waxite is a newly discovered natural waxite whose main constituent mineral is pyrophyllite and contains 0.5 to 5 wt% of carbon.

As of now, the chemical analysis results show that the carbon content is 0.5~5Wt.
%, and no other figures were available. In addition, the carbon component is uniformly dispersed within the waxite structure, and unlike carbon raw materials that are added separately, the carbon component in this waxite is approximately 1
It is difficult to oxidize even in a high-temperature oxidizing atmosphere of 1,000°C and has excellent oxidation resistance. Production areas include Shimohei District, Iwate Prefecture. As shown in Table 1, conventionally produced waxite does not contain any carbon components and is A1.

The content is about 20 wt%, and the fire resistance is 26 to 3 degrees. Conventional refractory materials for tapping iron containing this waxite have drawbacks such as the structure collapses due to thermal expansion when used as a main trough, the degree of filling of the refractory material is lost, strength decreases, and damage due to wear progresses. Although it cannot be said to be sufficient, it is superior in corrosion resistance when compared to a material using a shad material having an Al2O3 content of 40 to 50 wt%.

In other words, this is thought to be because waxite itself is dense and difficult to wet, which suppresses penetration of hot metal and molten slag.
The present invention solves the above-mentioned drawbacks and provides a highly corrosion-resistant and inexpensive refractory material for blast furnace tapping that further suppresses the penetration of hot metal and slag, and uses pyrofluorite material that has never been used in the past. A refractory material containing carbon-containing waxite raw materials.

That is, the present invention uses pyrofluorite as the main constituent mineral and natural waxite containing 1 wt% or more of carbon as the main raw material,
This is a refractory material for blast furnace tapping made by kneading one or more of silicon carbide, carbon, metallic silicon, etc. in combination and adding an appropriate amount of a binder.

As mentioned above, the pyrophyllite carbon-containing waxite mentioned here has carbon components uniformly dispersed in its structure, and has Al2C
), the content is higher than conventional ones and the fire resistance is 5 to 30.
33, and is characterized by a low coefficient of thermal expansion.

The reason why the carbon content is limited to 1 wt% or more is that if it is less than that, the effect of carbon content, that is, the wettability to hot metal and slag, and the fire resistance will not be improved. A more preferable range of these compositions is 40 to 70 wt% of pyrophyllite carbon-containing waxite, 2 to 10 wt% of carbon, 10 to 40 wt% of silicon carbide, and 1 to 7 wt% of metallic silicon, and these are mixed at an appropriate particle size. Refractory materials kneaded with a binder are suitable for tapping.

In other words, unlike the carbon that is added and blended, the carbon component distributed within the dolomite structure is difficult to oxidize even when used at high temperatures.
Prevents the infiltration of slag and extends the life of the refractory lining. On the other hand, as a result of discovering a new raw material with properties different from that of general wax stone, which is in demand today for resource saving and effective use of resources, and conducting various experiments and studies on its uses, the present invention was arrived at. In addition to the effects of the main composition of the system, there are also great benefits from the perspective of effective resource utilization in Japan, a resource-poor country.

Examples will be described below.

Example 1 As shown in Table 2, formulations of the present invention product and comparative product were created,
Pressure vibration molding at 3600 PM using a vibrator and 300
×300×2007077! A molded body was obtained.

The bulk specific gravity and porosity of the constructed body were measured according to JISR22O5, and the compressive strength was measured according to the JISR22O6 test method. Corrosion resistance was tested by mixing pig iron and blast furnace slag in a volume ratio of 1:1, heating and melting at 1,550°C, cutting the specimen into a certain shape, placing it inside a cylindrical shape, and rotating it nine times while heating. Then drain the slag. After repeating this cycle of charging, rotating, and discharging four times, the erosion dimensions of the specimens were measured and expressed as an index with the erosion dimension of one of the specimens as 100. From the measurement results of these substances (Table 2), it was confirmed that the products of the present invention were superior in strength and corrosion resistance compared to comparative products. Example 2 A formulation for stamping was prepared as shown in Table 3, and after kneading, Amsler molding was performed at a pressure of 100 k91 cT1. Each physical property was measured in the same manner as in Example 1, and the results were summarized in Table 3. It is shown in Table 3.

From this result, it was confirmed that the compressive strength and corrosion resistance of the product of the present invention were better than those of the comparative product.

Claims (1)

[Claims] 1 Main constituent mineral is pyrophyllite and 1wt of carbon
A refractory material for blast furnace tapping, which is made by using natural waxite containing % or more as the main raw material, combining it with one or more of silicon carbide, carbon, and metallic silicon, adding a binder, and kneading it.