SU1359270A1 - Refractory compound - Google Patents

Description

The invention relates to the refractory industry and can be used for the manufacture of firing refractory products used in the most worn out elements of footers of smelters of ferrous and non-ferrous metallurgy.

The purpose of the invention is to increase abrasion resistance while maintaining a high heat resistance of the refractory mass.

The proposed combination of components allows a refractory with a heat-resistant micro-fractured structure due to the use of materials with different thermal expansion coefficients. Thus, corundum, magnesium aluminate and magnesium chromite have KTP 8-9-10, while periclase has KTP 14-15-10. The granular corundum is characterized by a very high hardness (9 according to the Mohs scale), therefore its use in the charge improves the abrasion resistance of the minerals in the service,

When the corundum content in the mass is less than 10%, there is no significant improvement in abrasion resistance. The corundum content of more than 30% contributes to a significant increase in the size of the cracks (about 10-30 times. As a result, the mechanical strength of the refractory material is significantly reduced.

A chemically synthesized mixture of chromite and magnesium aluminate in a given ratio is obtained by co-precipitating from aqueous solutions of magnesium chromate or dichromate and aluminum hydroxide, followed by heat treatment of the resulting product and grinding it to a powder fraction less than 0.06 mm.

The ratio of chromite and magnesium aluminate from 3: 7 to 7: 3 allows obtaining a high degree of homogenization, synthetically synthesized, which causes a uniformly micro-fractured refractory structure with an optimal pore size, which ensures high temperature resistance of the products.

The introduction of a chemically synthesized mixture of chromite and magnesium aluminate of less than 10% entails an increase in porosity and, as a consequence, a significant decrease in slag resistance. When the content of this mixture is more than 30%, the extrusion of the mass is worsened, repressive cracks are observed in the products, which significantly reduces all the characteristics of the refractories.

Products are manufactured using well-known technological methods and equipment.

The mass is prepared as follows.

Grain components in the grain 0.5-3.0 mm (corundum, fused periclase or periclazochromite) are mixed for 1-2 minutes in mixing runners, moistened with a sulfite yeast brewing density of 21-1.22 g / cm and adding finely ground the component (0.06 mm) is a chemically synthesized mixture of chromite and magnesium aluminate. The mass is stirred for 3-4 minutes, after which the product is pressed from it at a specific pressure of 130 MPa and burned for 4 hours at 1740i ± 10 ° C,

The compositions and properties of samples from the proposed and known masses are given in the table.

The obtained test results indicate the possibility of obtaining refractory products with high performance characteristics, so that using them in lining allows you to increase the resistance of thermal units by 1.5 times.

In addition, simple manufacturing techniques do not require additional equipment in refractory plants.

Prototype Granular fused

periclazochromite Basis

Granular fused

chrome alumina spinelide

5-30

Bronze binder from the group: fused chromitopericlase, fused periclase, mixture of fused periclase and chromium-alumina pyrene 20-40

Fused periclazochromite 70

Granular corundum

ten

Chemically synthesized mixture of chromite and magnesium aluminate (3: 7)

Fused periclazochromite

Corundum

Chemically synthesized mixture of chromite and magnesium aluminate (5: 5)

Fused periclazochromite

Granular corundum

Chemically synthesized mixture of chromite and magnesium aluminate (7: 3).

Fused periclazochromite

Granular corundum 20

8-U 7.8-8.6

3.3

1280 12.1

ten

3.2

1060 12.6

ten

3.1

94.0 12.80

Chemically synthesized mixture of chromite and magnesium aluminate (3; 7)

Fused periclacosohromite

Granular corundum

Chemically synthesized mixture of chromite and. magnesium aluminate (5: 5)

Fused periclacosohromite

Granular corundum

Chemically mixed with chromite and magnesium aluminate (7; 3)

Fused periclacosohromite

Granular corundum

Chemically synthesized mixture of chromite and magnesium aluminate (3: 7)

Fused periclacosohromite

Granular corundum

Chemically synthesized mixture of chromite and magnesium aluminate (5: 5)

Table continuation

eleven

2.9

96.0 11.4

12

2.7

89.0 12.4

12. 2.6

91.0 12.8

eleven

2

85.0 13.2

12

2.0

90.0 13.6

Fused periclacosohromite

Granular corundum

Chemically synthesized mixture of chromite and magnesium aluminate (7: 3)

13

2.0.

86.0 14.2

Claims (1)

FIRE-RESISTANT MASS, containing granular fused periclase chromite and a finely ground binder based on aluminum, chromium and magnesium oxides, characterized in that, in order to increase abrasion resistance while maintaining high heat resistance, it additionally contains granular corundum, and chemically synthesized material as a finely ground binder - chromite and magnesium aluminate in a ratio of 3: 7 to 7: 3 in the following ratio, wt. Granular fused periclase chromite A finely ground chemically synthesized mixture of chromite and magnesium aluminate in a ratio of 3: 7 to 7: 3 Granular corundum 50-70 10-30 10-30