Composite ceramic mixture

Abstract

FIELD: construction.SUBSTANCE: invention relates to building materials and can be used in the production of ceramic building materials, for example, for facing bricks. The composite ceramic mixture comprises Cambrian clay, screened granulated blast furnace slag with a particle size of less than 1.0 mm, sodium metasilicate pentahydrate Na2SiO3⋅5H2O, non-activated mineral powder “МП-2”, with the following ratio of components, wt.%: Cambrian clay 47-60; said granulated blast furnace slag 20-26; said sodium metasilicate pentahydrate 5-7; said mineral powder 15-20.EFFECT: reduction in the thermal conductivity coefficient of a ceramic shard.1 cl, 3 tbl

Description

[0001] The invention relates to building materials and can be used in the production of ceramic building materials, for example, for facing bricks.

[0002] A known composite ceramic mixture contains Cambrian clay, granulated slag of fractions 0.6-5 mm, glass microspheres of fractions 15-200 μm and oil-contaminated soil, in the following ratios of components, wt. %: Cambrian clay 59-64; granulated slag 24-25; glass microspheres 6-7; oil-contaminated soil 6-9. (RU No. 2720340, C04B 33 / 132, C04B 33 / 138, published 20.02.2011. Bulletin No. 5).

[0003] The disadvantage of this composition is the high value of the thermal conductivity coefficient of the ceramic shard

[0004] The closest to the proposed composition is a composite ceramic mixture containing Cambrian clay, granulated blast furnace slag with a particle size of less than 0.63 mm, glass microspheres of fractions of 15-200 μm, microcalcite MK-200 in the following ratios of components, wt. %: Cambrian clay 51-59, the said granulated blast furnace slag 19-22, the said glass microspheres 4-6, the said microcalcite 18-21. (RU No. 2850532 C04B 33 / 132, C04B 33 / 138, C04B 33 / 04, C04B 111 / 20, published 12.11.2025 Bulletin No. 32).

[0005] The disadvantage of this composition is the high value of the thermal conductivity coefficient of the ceramic shard.

[0006] The objective of the proposed invention is to reduce the thermal conductivity coefficient of a ceramic shard.

[0007] The stated objective is achieved in that the composite ceramic mixture containing Cambrian clay, granulated blast furnace slag, a clarifying microfiller, additionally contains sodium metasilicate pentahydrate Na2SiO3⋅5H2O, contains screened granulated blast furnace slag with a particle size of less than 1 mm as granulated blast furnace slag, and contains non-activated mineral powder MP-2 as a clarifying microfiller in the following component ratios, wt. %:

[0008] Cambrian clay 47-60 the specified granulated blast furnace slag 20-26 the specified sodium metasilicate pentahydrate 5-7 the specified mineral powder 15-20

[0009] The reduction in the thermal conductivity of a ceramic body after firing is determined by the combined presence of granulated blast-furnace slag, which has a developed porous structure, sodium metasilicate pentahydrate (0.5 to 1.5 mm in size) with inherent porosity, and mineral powder mixed with clay. This leads to the formation of a liquid phase and intensive sintering along the interface between the ceramic matrix and the sodium metasilicate pentahydrate particles, forming closed, fused pores. Additional microporosity is introduced by the mineral powder, which contains calcium and magnesium carbonates, which decompose during firing. All this leads to a decrease in the density of the ceramic body and, consequently, a decrease in the thermal conductivity.

[0010] In addition, the use of screened granulated blast furnace slag in combination with mineral powder allows for the production of finished products with a peach-colored front surface.

[0011] Example of specific implementation

[0012] The products are manufactured using the standard ceramic brick production technology, using plastic molding and firing at a temperature of 1000°C. The clay raw material used for the ceramic bricks is low-melting, red-burning Cambrian clay from the Krasny Bor deposit (see Table 1).

[0013] Granulated blast-furnace slag screened on a 1 mm mesh is used as a leaning agent. During iron and steel smelting, approximately one ton of granulated blast-furnace slag is produced for every ton of metal produced. Rapid cooling (granulation) of the slag results in glass, with a content reaching 80% or more by weight. The crystalline component includes gehlenite, monticellite, spinel, and other silicates, aluminates, and aluminosilicates of Ca and Mg. For example, Cherepovets granulated blast-furnace slag, which has inherent porosity, has an amorphous structure, contains 2CaO-SiO2, and small amounts of iron and manganese compounds. The chemical composition of Cherepovets slag is presented in Table 2.

[0014] Sodium metasilicate pentahydrate Na2SiO3⋅5H2O, which is spherical particles ranging in size from 0.5 to 1.5 mm and exhibiting intrinsic porosity, was used as the component initiating the formation of isolated microporosity. The bulk density is 0.7 g / cm3. 3 . Produced according to TU 2145-001-13985121-2007 "Sodium metasilicate pentahydrate".

[0015] The non-activated mineral powder MP-2 according to GOST 32761-2014 was used as a lightening component. It is a finely ground powder obtained by grinding carbonate rocks without the addition of activating substances.

[0016] Brick samples, hand-molded in 160×40×40 mm molds, were dried at 100°C to a moisture content of 4-6% and fired at a maximum temperature of 1000°C in an electric furnace for at least 1 hour. After firing, the thermal conductivity coefficient was determined according to GOST 7076-87. The results are presented in Table 3.

[0017] Analysis of the results presented in Table 3 indicates that the introduction of screened granulated blast furnace slag into the composition of the ceramic mass, in combination with mineral powder and sodium metasilicate pentahydrate, leads to a redistribution of the porous structure towards the formation of closed micropores, which contributes to a decrease in the thermal conductivity coefficient by 38% compared to the values ​​​​achieved by the prototype.

[0018] The use of man-made raw materials in the form of granulated blast furnace slag facilitates waste recycling and expands the raw material base for producing facing ceramic bricks.

[0019]

Claims

A composite ceramic mixture containing Cambrian clay, granulated blast furnace slag, and a brightening microfiller, characterized in that it additionally contains sodium metasilicate pentahydrate Na2SiO3⋅5H2O, contains screened granulated blast furnace slag with a particle size of less than 1 mm as the granulated blast furnace slag, and contains non-activated mineral powder MP-2 as the brightening microfiller in the following component ratios, wt. %: Cambrian clay 47-60 the specified granulated blast furnace slag 20-26 the specified sodium metasilicate pentahydrate 5-7 the specified mineral powder 15-20

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