RU2277520C1 - Method for making wall ceramic articles (variants) - Google Patents

Abstract

FIELD: building industry.

SUBSTANCE: invention relates to wall and facing ceramics. Method for making wall ceramic articles involves mixing ground clay with leaning and swelling additives, wetting, molding of crude articles by plastic method, drying and roasting. As a leaning and swelling additives method involves using broken glass ground in common with a granulated and hydrophobizated pore-forming agent with granules size 0.1-2.0 mm taken in the following ratio of components, wt.-%: indicated broken glass, 3-30, and clay, the balance. As a pore-forming agent method involves using calcium or magnesium carbonates or their mixture and its amount in granules is 1-6% of the broken glass mass, and amount of a hydrophobizing agent is 1-10% of the broken glass mass. The surface of granulated broken glass smoothed by a hydrophobizing agent with a pore-forming agent can be represented as spherical or egg-shaped forms. By the second variant of a method the molding of crude articles is carried out by a method of semidry pressing. Invention provides expanding assortment of technical agents used in manufacturing low-shrinkage wall ceramic articles possessing the reduced heat conductivity coefficient with retention or improvement of physical-mechanical indices. Invention can be used in manufacturing heat-insulating articles - tiles, brick, blocks, wall panels and others.

EFFECT: improved making method of articles.

5 cl, 4 tbl, 2 ex

Description

The invention relates to the production of wall ceramics and can be used to obtain insulating products - tiles, bricks, blocks, wall panels, etc.

A known method of manufacturing wall ceramic products, including joint wet grinding of cullet, electrothermophosphoric slag and clay to a fineness of grinding - the residue on a sieve of 0.355 is not more than 4%, drying to a moisture of 4 ... 8%, molding blanks and subsequent firing at 980 ° C [ RF patent No. 2070177, cl. 6 C 04 B 33/02, 1996].

The disadvantages of this method are: high coefficient of thermal conductivity (0.72 ... 0.86 W / m · K), which leads to an increase in the consumption of building materials in construction; high density (1850 ... 2100 kg / m ³ ), which requires an increase in the cost of materials at the manufacturing stage and, as a result of this, makes the mass of wall structures heavier; high fire shrinkage (up to 12 vol.%) contributes to the occurrence of stresses and structural defects that adversely affect the strength characteristics of the calcined material. These shortcomings worsen the technological and operational characteristics of wall ceramic products.

Closest to the proposed solution is a method of manufacturing wall ceramic products, which consists in mixing a mass consisting of ground clay (53-93 wt.%), Grains expanding during heating of an additive with an initial size of not more than 2 mm, consisting of vermiculite, or hydrophlogopite or hydrobiotite (2-42 wt.%) and a scrubber consisting of sand, or ash, or slag with a grain size of not more than 2 mm (4-45 wt.%). Products are molded from the mixed mass in a plastic way, which, after drying, are fired in a tunnel oven at 950 ° C with an isothermal exposure of 2 hours [RF Patent No. 1780276, cl. 6 C 04 B 33/00, 1995].

The disadvantages of the prototype are: high coefficient of thermal conductivity, increased overall shrinkage during drying and firing (up to 5 ... 7.9 vol.%) Of the resulting wall ceramic products.

The present invention solves the problem of expanding the arsenal of technical means for the production of low-shrink wall ceramic products with a reduced coefficient of thermal conductivity while maintaining or improving physical and mechanical characteristics.

The technical result is achieved by two options for solving the problem.

According to the first solution to the problem, in a method of manufacturing wall ceramic products, including mixing ground clay with an expanding and intumescent additives, moistening, molding raw products in a plastic way, drying and firing, according to the proposed solution, a cullet, ground together with a blowing agent, is used as an exhaust and intumescent additives granular and hydrophobized with a particle size of 0.1 ... 2.0 mm in the following ratio of components, wt.%:

cullet, ground together with the blowing agent, granular and hydrophobized 3 ... 30 clay rest

calcium or magnesium carbonates or a mixture thereof is used as a blowing agent, its amount in granules is 1 ... 6% of the mass of cullet, and the amount of water repellent is 1 ... 10% of the mass of cullet.

The surface of the granular cullet smoothed by a water repellent with a blowing agent has a spherical or ovoid shape.

According to the second solution to the problem in a method of manufacturing wall ceramic products, including mixing ground clay with exhaust and intumescent additives, moistening, molding raw products, drying and firing, according to the proposed solution, the molding of raw products is carried out by semi-dry pressing, and as exhaust and intumescent additives use cullet, ground together with a pore former, granular and hydrophobized with a granule size of 0.1 ... 2.0 mm in the following ratio of components, wt.%:

cullet, ground together with the blowing agent, granular and hydrophobized 3 ... 30 clay rest

calcium or magnesium carbonates or a mixture thereof is used as a blowing agent, its amount in granules is 1 ... 6% of the mass of cullet, and the amount of water repellent is 1 ... 10% of the mass of cullet.

Semi-dry pressing is carried out at a specific pressure of 2-5 MPa.

The surface of the granular cullet smoothed by a water repellent with a blowing agent has a spherical or ovoid shape.

Comparison of the method according to the first embodiment with the prototype made it possible to establish that the proposed solution is distinguished by the introduction of a cullet, ground together with a pore former, granular and hydrophobized, having grain sizes of 0.1-2.0 mm, as an exhausting and intumescent additive; calcium or magnesium carbonates or a mixture thereof is used as a blowing agent, its amount in granules is 1 ... 6% of the mass of cullet, and the amount of water repellent is 1 ... 10% of the mass of cullet. The introduction of the proposed granules allows you to simultaneously plasticize the mixture, which leads to a decrease in the molding moisture content, to reduce the thermal conductivity and density of the finished product by 1.4 ... 1.7 times. Thus, the proposed solution has the criterion of "novelty."

Comparison of the method according to the second embodiment with the prototype made it possible to establish that the proposed solution is distinguished by the introduction of a cullet, ground together with a pore former, granular and hydrophobized, having grain sizes of 0.1-2.0 mm and a smoothed surface as raw material and intumescent additives while the amount of pore-forming agent is 1 ... 6%, and the amount of water repellent agent is 1 ... 10.0% of the mass of cullet, and the formation of raw products is carried out by the method of semi-dry pressing at a specific pressure of 2-5 MPa. The introduction of the proposed granules allows plasticizing the mixture at the same time, as well as reducing the molding moisture and pressing pressure to 2 MPa, reducing the thermal conductivity and density of finished products by 1.4 ... 1.8 times. Thus, the proposed solution also has the criterion of "novelty."

In the study of other technical solutions, the use of the introduction of the cullet, ground together with a pore former, granulated and hydrophobized, as proposed by the authors of the introduction into the raw ceramic mass as granule and intumescent, was not identified, therefore, the claimed solution does not follow explicitly from the prior art, which allows us to conclude on the compliance of the proposed solutions to the criterion of "inventive step".

When implementing the proposed method for the manufacture of wall ceramic products, the raw materials of the mass and granular filler, identical for the two options, were used as raw materials.

Characterization of mass components:

1. As cullet used the battle of green container glass, the city of Voronezh. The initial battle of container glass is crushed in a hammer mill, washed and dried in a washing and drying drum, stored in a storage bin. The chemical composition of the battle of container glass is given in table 1.

2. As a blowing agent used calcium carbonates (chalk, limestone), magnesium carbonate (magnesite) and their natural mixture (dolomite):

- technical dispersed chalk MTD-2 according to TU - 21-020350-06-92, JSC Building Materials, Belgorod;

- limestone of the Yashkinsky deposit;

- magnesite, Satka, Chelyabinsk region SM-1 according to TU 14-8-64-73;

- Dolomite, Schelkovo field of the Moscow region.

The chemical compositions of chalk, limestone, magnesite and dolomite are given in table 1

3. As clay used loam of the Shebekinsky deposit, Belgorod region. Refractoriness 1180 ... 1270 ° С. Water solubility - 28.7% (according to GOST 9169-75). The main clay mineral is montmorillonite. The color after firing is greenish yellow. The chemical composition of the loam of the Shebekinsky deposit is presented in Table 1.

4. When granulating cullet powder, ground together with a blowing agent, on a plate granulator, an aqueous solution of silicate glue (liquid glass) was used in accordance with TU 2385-001-54824507-2000. The use of this binder significantly increases the strength of the resulting granules after drying.

5. As a water-repellent surface of cullet, ground together with a pore former and granular, used paraffin oil grade P-2 (GOST 23683-89) in the molten state. The thickness of the paraffin layer on the granulate surface depends on the viscosity of the paraffin melt. The viscosity of a paraffin melt is highly dependent on temperature. Thus, by changing the temperature of the paraffin melt, it is possible to control the thickness of the hydrophobic film on the surface of the granulate in order to obtain the most rounded even surface of the granules, which subsequently allows the formation of spherical and round pores in the mass of the finished product.

Table 1 The chemical composition of the components of ceramic masses No. p / p Component The content of oxides, wt.% SiO ₂ Al ₂ About ₃ TiO ₂ Fe ₂ O ₃ Cao MgO K ₂ O + Na ₂ O SO ₃ P.p.p. one. Glass Fight 65,2 10.7 0.8 1,2 6.5 0.7 14.7 0.2 - 2. Chalk Belgorod 1.3 0.7 0.1 0.1 54.7 0.3 - - 42.8 3. Loam Shebekinsky 58.9 7.6 0.4 1,2 10.1 2,8 3.4 0.4 15,2 four. Limestone Yashkinsky 1.7 0.8 0.1 0.4 52.3 1,1 1,2 0.2 42,2 5. Magnesite Satkinsky 1,2 0.9 0.2 0.4 0.8 46.0 0.5 0.3 49.7 6. Dolomite Schelkovsky 0.8 0.2 0.1 0.2 30.9 22.8 0.7 0.2 44.1

The hydrophobized surface of a cullet, ground together with a pore former and granulated, without being wetted with water, better resists mechanical stresses when mixed with clay, for example, in a screw mixer, retains its geometric dimensions during the formation of raw products, reduces water demand, which plasticizes the molding mass.

To obtain a granular filler in the implementation of the proposed method for the manufacture of wall ceramic products, crushed glass breakage is dosed with calcium carbonates (pore former) - chalk, limestone or magnesium carbonate - dolomite by the gravimetric method and ground in a ball mill until the specific surface reaches 300 ... 500 m ² / kg The granulation of the charge is carried out on a plate granulator with irrigation of its surface with a 10% aqueous solution of liquid glass, which improves the formation process and increases the mechanical strength of the granules. The granules are dried in a belt-mesh dryer. At the outlet of the dryer, the granules reach a minimum moisture content of 1 ... 2%. Screening of granules with a size of less than 0.1 mm and more than 2.0 mm is performed on a vibrating screen; rejected granules are sent back for recycling. Granules, the size corresponding to the technical conditions, are sent for treatment with a water repellent. The surface treatment of cullet, ground together with a pore former and granular, hydrophobic component consists in filling granules of 0.1 ... 2.0 mm screened on sieves into a tank with a melt of hydrophobizing agent, mixing this mass for 5 ... 10 minutes and removing the liquid phase through a mesh partition with a mesh size of slightly less than 0.1 mm. After cooling, the obtained granules are loaded into the stock hopper, they are completely ready for technological use.

Analyzing the results of physical and mechanical tests of a series of experimental samples, we can conclude that:

- according to their ability to form the porous structure of fired ceramic materials, joint grinding of cullet with a blowing agent is preferable to achieve a specific surface of 300 ... 500 m ² / kg;

- as a blowing agent, you can use chalk, limestone, magnesite or a mixture of these components (dolomite);

- based on the strength characteristics of the granules of cullet, ground together with the blowing agent, it is preferable to dry them to a moisture content of 2%;

- the most preferred form of cullet, ground together with a pore former, granular and hydrophobized - spherical and ovoid, which is achieved by selecting the viscosity of the hydrophobizing solution.

A method of manufacturing wall ceramic products is as follows in two ways.

According to the first embodiment, clay raw materials were ground to a particle size of less than 0.1 mm, dosed, cullet, ground together with a pore former, granulated and hydrophobized, with a grain size of 0.1 ... 2.0 mm in the ratio by dry weight specified in table 2. The mixture of dry components was moistened with water to the molding moisture according to [Frost II. Technology of building ceramics. Kiev: “Vishka Shkola”, 1980. - P.79-84], mixed until even distribution of granules and clay. Raw products from the resulting mixture were molded in a plastic way on a belt press. Reducing humidity during the molding of products in comparison with the methods described in [RF Patent No. 2070177, cl. 6 C 04 B 33/02, 1996; RF patent No. 1780276, class 6 C 04 B 33/00, 1995], contributes to a marked increase in workability of raw mixes prepared by the present method, due to better slip between clay particles and the hydrophobized surface of the granules. Compared to the prototype, the water solubility of raw materials can be reduced by 6 ... 7.7%, which also facilitates the drying of raw materials, while the shrinkage during drying is minimal. Products are dried to a residual moisture content of 0.5 ... 2% similarly [RF Patent No. 1780276, cl. 6 C 04 B 33/00, 1995; Moroz I.I. Technology of building ceramics. Kiev: “Vishka school”, 1980. - S.95-101], and then burned at a temperature of 950 ° C in the same way [I. Moroz. Technology of building ceramics. Kiev: “Vishka school”, 1980. - P.121-128].

Example 1. Pre-dried crushed and sieved through a sieve with a hole size of 0.1 mm Shebekinsky loam in an amount of 7.8 kg (78%, see table 2, mixture 1), 2.2 kg were added to this clay (22 %, see table 2, a mixture of 1) cullet, ground together with a pore former, to a specific surface of 400 m ² / kg, granular and hydrophobized, with a grain size of 0.1 ... 2.0 mm (consisting of cullet powder, ground together with 3 wt.% chalk, granular, sifted through a sieve with a mesh diameter of 2.0 mm and remaining on the sieve of 0.1 mm and processed of 0.22 kg of molten paraffin - 10% relative to the mass of cullet, see table 2, mixture 1). These two components were mixed in a laboratory screw mixer and, at the same time, 0.94 kg of water were sprayed during mixing (see Table 3, mixture 1). The resulting mass was molded in a plastic way on a belt screw press. The obtained strength of the raw material allows the transfer and drying of samples without any restrictions. The formed samples in the form of tiles with a size of 192 × 142 × 9 mm and cylinders with a diameter and height of 50 mm (the last samples were intended to determine the compressive strength) were dried to a residual moisture content of 2%, and then fired at a maximum temperature of 950 ° C with exposure 2 hours, i.e. The production conditions for the production of building ceramic bricks were modeled [Moroz I.I. Technology of building ceramics. Kiev: "Vishka school", 1980. - P.89-128]. After cooling, product samples were tested for strength, and density, general shrinkage, and thermal conductivity were determined. The test results are shown in table 3 (mixture 1).

Similarly, all other mixtures were prepared according to the claimed method for producing ceramic mass and, accordingly, based on it, samples of wall products and tiles, including those with exorbitant sizes of hydrophobized granules (compositions 5, 6, 11, 12, 17, 18, 23 and 24).

The compositions of the mixtures and characteristics of the components are given in table.2. The properties of the obtained ceramic products are given in table.3.

An analysis of the data of Table 3 of the test results of the properties of wall ceramic samples made according to the first embodiment of the proposed method shows the following.

1. All mixtures 1-4, 7-10, 13-16 and 19-22 meet the requirements of GOST 7025-91 “Brick and ceramic and silicate stones”.

2. Introduction to the composition of the mass of cullet, ground together with a blowing agent, granular and hydrophobized, in the claimed quantities and grain size of 0.1 ... 2.0 mm allows you to get durable high-quality wall ceramic products.

3. The fired ceramic products obtained from the raw mixes 13, 14, and 16 have a negative shrinkage, i.e. there is a uniform increase in the linear and volumetric sizes of the calcined samples in comparison with the sizes of the initial raw products.

4. To reduce the number of grains in the raw material mass of less than 3 wt.% Is impractical, because the resulting ceramic products according to technical characteristics are denser than those of the prototype, and despite the fact that the products meet the requirements of GOST 7025-91, their thermal insulation characteristics are insufficient, therefore, compositions 3, 9, 15 and 21 are accepted as boundary ones.

The increase in the number of grains in the mass of more than 30 wt.% Is impractical, because the strength of the obtained wall ceramic materials decreases due to a decrease in the share of the clay component in the charge and a violation of the geometric dimensions of the products during the firing process, their physical and mechanical characteristics do not meet the requirements of GOST 7025-91, therefore, compositions 4, 10, 16 and 22 are accepted as boundary ones.

table 2 The composition of the ceramic mass Mix No. Components, wt.% Loam Shchebekinsky Cullet, ground together with a pore former, granular and hydrophobized; granule size, mm less than 0.1 0.1-2.0 more than 2.0 I. Granules of cullet, ground together with 3% chalk one 78 - 22 (spherical shape) - 10 2 79 - 21 (ovoid form) - 5 3 97 - 3 (smoothed shape) - one four 70 - 30 (smoothed shape) - 10 5 78 22 (ovoid form) - - 10 6 78 - - 22 (spherical shape) 10 II. Granules of cullet, ground together with 1% magnesite 7 78 - 22 (spherical shape) - 10 8 79 - 21 (ovoid form) - 5 9 97 - 3 (smoothed shape) - one 10 70 - 30 (smoothed shape) - 10 eleven 78 22 (ovoid form) - - 10 12 78 - - 22 (spherical shape) 10 III. Granules of cullet, ground together with 6% limestone 13 78 - 22 (spherical shape) - 10 fourteen 79 - 21 (ovoid form) - 5 fifteen 97 - 3 (smoothed shape) - one 16 70 - 30 (smoothed shape) - 10 17 78 22 (ovoid form) - - 10 eighteen 78 - - 22 (spherical shape) 10 IV. Granules of cullet, ground together with 4% dolomite 19 78 - 22 (spherical shape) - 10 twenty 79 - 21 (ovoid form) - 5 21 97 - 3 (smoothed shape) - one 22 70 - 30 (smoothed shape) - 10 23 78 22 (ovoid form) - - 10 24 78 - - 22 (spherical shape) 10

5. The use of cullet, ground together with a pore former, granular and hydrophobized, with a particle size of less than 0.1 mm does not allow to obtain ceramic products of low density and with a reduced coefficient of thermal conductivity, because too small granules during firing behave like fluff, cause linear and volumetric deformations of products during firing, increase the density, thermal conductivity and volumetric shrinkage of the samples. Thus, the compositions 5, 11, 17 and 23 go beyond the boundaries of the proposed method.

Table 3 Properties of ceramic products obtained in the first embodiment Mix No. Shrinkage, vol. % The coefficient of thermal conductivity, W / m · K Density, kg / m ³ The limit of compressive strength, MPa Forming humidity,% one 0.5 0.448 1410 33.9 9,4 2 0.7 0.454 1429 32,7 9.5 3 6.8 0.723 1991 27.9 16,4 four 0.2 0.559 1312 17.0 8.7 5 7.2 0.789 2031 26.7 10.6 6 3.4 0.745 1419 10.1 9.5 7 3.0 0.628 1689 35.1 9,4 8 3.4 0.652 1693 34.8 9.5 9 6.9 0.727 1994 27.8 16.3 10 1,2 0.618 1532 19,2 8.7 eleven 7.4 0.781 2039 27.1 9.6 12 4,5 0.739 1709 16.9 9.5 13 -3.4 0.422 1398 29.1 9,4 fourteen -3.5 0.432 1419 28.6 9.5 fifteen 6.8 0.729 2053 28.6 16,4 16 -5.0 0.524 1301 20,0 8.7 17 7.5 0.771 2070 27.3 9.6 eighteen 1,0 0.751 1400 8.2 9.5 19 0.1 0.439 1406 32.8 9,4 twenty 0.2 0.445 1425 31.6 9.5 21 6.9 0.724 2006 28.0 16.3 22 0.1 0.550 1308 16.8 8.7 23 6.9 0.779 2021 25.5 10.6 24 2.7 0.740 1414 9.2 9.5 25 (prototype) 6.8 0.721 1990 27.5 16.5

6. The use of cullet, ground together with a pore former, granular and hydrophobized, with a particle size of more than 2.0 mm is also impractical, because the resulting system of large pores contributes to the occurrence of convective heat transfer in them, which reduces the thermal insulation characteristics of the materials obtained (mixtures 6, 12, 18 and 24), when firing such a mass, serious structural defects and its friability are observed, which reduce the strength characteristics, violate the geometric dimensions of the resulting wall ceramic products. Thus, the compositions 6, 12, 18 and 24 go beyond the boundaries of the proposed method.

The inventive method of manufacturing wall ceramic products according to the first embodiment in comparison with the prototype has the following advantages:

1) thermal insulation properties are improved by 30-35%;

2) the density while maintaining the required physical and mechanical characteristics is reduced by 20-25%;

3) introducing a glass cube, ground together with a pore former, granular and hydrophobized, with a grain size of 0.1 ... 2.0 mm into the raw material mixture instead of raw vermiculite and a detergent, we simultaneously plasticize the mixture, while the molding properties of the blends are improved so much that can reduce the moisture content of the workpieces when molding raw products in a plastic way by 6 ... 7.7% compared with the prototype (table 3);

4) wall ceramic products obtained as a result of firing have a uniform closed-porous hardened structure with minimal volumetric shrinkage defects.

According to the second variant, clay raw materials were ground to a particle size of less than 0.1 mm, dosed, cullet, ground together with a pore former, granulated and hydrophobized, with a grain size of 0.1 ... 2.0 mm was added in the ratio by dry weight indicated in table 2. The mixture of dry components was moistened with water to the molding moisture according to [Frost II. Technology of building ceramics. Kiev: “Vishka Shkola”, 1980. - P.91], mixed until even distribution of granules and clay. The mixture was molded by semi-dry pressing under a pressure of 2 ... 5 MPa. The pressure reduction during the molding of products in comparison with the methods described in [RF Patent No. 2070177, cl. 6 C 04 B 33/02, 1996; Moroz I.I. Technology of building ceramics. Kiev: “Vishka Shkola”, 1980], contributes to a marked increase in workability of raw mixes prepared by the present method, due to better gliding between clay particles and the hydrophobized surface of the granules. The water solubility of raw materials can be reduced to 7%, which also facilitates the drying of raw materials, while shrinkage during drying is practically absent. The products were dried to a residual moisture content of 0.5 ... 2% similar to the prototype, and then fired at a temperature of 950 ° C similarly [I. Moroz Technology of building ceramics. Kiev: “Vishka school”, 1980. - P.121-128].

Example 2. Weighed previously dried crushed and sieved clay with a mesh size of 0.1 mm - Shebekinsky loam in the amount of 7.8 kg (78%, see table 2, mixture 1), 2.2 kg was added to this clay cullet, ground together with a pore former to a specific surface of 400 m ² / kg, granular and hydrophobized, with a grain size of 0.1 ... 2.0 mm (consisting of cullet powder, ground together with 3 wt.% chalk, granular, sifted through a sieve with a mesh diameter of 2.0 mm and 0.1 mm remaining on the sieve and processed 0.22 kg p fused paraffin - 10% relative to the mass of cullet, see table 2, mixture 1). These two components were mixed in a laboratory screw mixer and, at the same time, 0.8 kg of water was sprayed during mixing (Table 4, mixture 1). The resulting mass was molded by semi-dry pressing on a hydraulic press under a pressure of 2 MPa at a moisture content of 8%. The obtained strength of the raw material allows the transfer and drying of samples without any restrictions. The formed samples in the form of tiles with a size of 192 × 142 × 9 mm and cylinders with a diameter and height of 50 mm (the last samples were intended to determine the compressive strength) were dried to a residual moisture content of 2%, and then fired at a maximum temperature of 950 ° C with exposure 2 hours, i.e. The production conditions for the production of building ceramic bricks were modeled [Moroz I.I. Technology of building ceramics. Kiev: "Vishka school", 1980. - P.89-128]. After cooling, the samples of the material were tested for strength, and the density, general shrinkage, and thermal conductivity were determined.

Similarly, all other mixtures were prepared according to the claimed method for producing ceramic mass and, accordingly, based on it samples of wall products and tiles, including those with exorbitant sizes of hydrophobized granules (compositions 5, 6, 11, 12, 17, 18, 23 and 24), as well as the known composition of the mass 25 (prototype - according to the patent of the Russian Federation No. 1780276, class 6 C 04 B 33/00, 1995, table 5).

The ratio of raw materials is given in table.2. The test results are shown in table 4.

Analysis of the data of table 4 of the test results of the properties of samples of wall and facing ceramics made according to the second embodiment of the proposed method, shows the following.

1. Mixtures of compositions 1-4, 7-10, 13-16 and 19-22 meet the requirements of GOST 7025-91 "Brick and ceramic and silicate stones".

2. Introduction to the composition of the mass of cullet, ground together with a blowing agent, granular and hydrophobized, in the claimed quantities and grain size of 0.1 ... 2.0 mm allows you to get durable high-quality wall ceramic products.

3. Calcined ceramic products obtained from raw mixtures 13, 14, 16, and 19, 20 and 22 have a negative shrinkage, i.e. there is a uniform increase in the linear and volumetric sizes of the calcined samples in comparison with the sizes of the initial raw products.

4. To reduce the number of grains in the raw material mass of less than 3 wt.% Is impractical, because the resulting ceramic products by technical characteristics are denser than those of the prototype, and despite the fact that the products meet the requirements of GOST 7025-91, their thermal insulation characteristics are insufficient, therefore, compositions 3, 9, 15 and 21 are accepted as boundary ones.

Table 4 Properties of ceramic products obtained in the second embodiment Mix No. Specific pressing pressure, MPa Shrinkage, vol. % The coefficient of thermal conductivity, W / m · K Density, kg / m ³ The limit of compressive strength, MPa Forming humidity,% one 2 0.8 0.454 1431 36.7 8 2 2 0.9 0.461 1444 35.9 8 3 5 6.1 0.734 1991 32,4 13 four 2 0.5 0.568 1330 21.1 7 5 3 6.2 0.751 1993 29.3 8 6 3 4.3 0.745 1433 11.0 8 7 2 3,1 0.637 1697 38,2 8 8 2 3.2 0.661 1712 37.7 8 9 10 5.7 0.739 1998 30.8 13 10 2 1,5 0.627 1549 22.1 7 eleven 3 6.3 0.746 2003 30,0 8 12 3 3.6 0.761 1728 18,4 8 13 2 -2.1 0.433 1419 32,0 8 fourteen 2 -2.2 0.432 1421 31,2 8 fifteen 5 6.3 0.739 1998 34.6 13 16 2 -3.5 0.533 1320 20.1 7 17 3 6.9 0.741 2019 28.1 8 eighteen 3 1,1 0.742 1424 10.1 8 19 2 -0.2 0.446 1428 34.6 8 twenty 2 -0.1 0.453 1440 33.8 8 21 10 6.0 0.749 1998 30.8 13 22 6 -0.3 0.559 1325 19,2 7 23 3 6.9 0.744 2019 27.1 8 24 3 3.0 0.754 1434 10,2 8 25 (prototype) 10 6.8 0.732 1990 27.5 16.5

The increase in the number of grains in the mass of more than 30 wt.% Is impractical, because the strength of the obtained wall ceramic materials decreases due to a decrease in the share of the clay component in the charge and a violation of the geometric dimensions of the products during the firing process, their physical and mechanical characteristics do not meet the requirements of GOST 7025-91, therefore, compositions 4, 10, 16 and 22 are accepted as boundary ones.

5. The use of cullet, ground together with a pore former, granular and hydrophobized, with a particle size of less than 0.1 mm does not allow to obtain ceramic products of low density and with a reduced coefficient of thermal conductivity, because too small granules during firing behave like fluff, cause linear and volumetric deformations of products during firing, increase the density, thermal conductivity and volumetric shrinkage of the samples. Thus, the compositions 5, 11, 17 and 23 go beyond the boundaries of the proposed method.

6. The use of cullet, ground together with a pore former, granular and hydrophobized, with a particle size of more than 2.0 mm is also impractical, because the resulting system of large pores contributes to the occurrence of convective heat transfer in them, which reduces the thermal insulation characteristics of the materials obtained (mixtures 6, 12, 18 and 24), when firing such a mass, serious structural defects and its friability are observed, which reduce the strength characteristics, violate the geometric dimensions of the resulting wall ceramic products. Thus, the compositions 6, 12, 18 and 24 go beyond the boundaries of the proposed method.

The inventive method of manufacturing wall ceramic products according to the second embodiment in comparison with the prototype has the following advantages:

1) thermal insulation properties are improved by 30-35%;

2) the density while maintaining the required physical and mechanical characteristics is reduced by 20-25%;

3) with the introduction of cullet, ground together with a pore former, granular and hydrophobized, with a grain size of 0.1 ... 2.0 mm into the raw material mixture, instead of raw vermiculite and hardener, plasticization of the mixture is carried out simultaneously, while the molding properties of the blends are improved so much, which allows to reduce the pressing pressure to 2-5 MPa and the humidity of the workpieces from 16.5% (prototype) to 7 ... 13% (table 4);

4) wall ceramic products obtained as a result of firing have a uniform closed-porous hardened structure with minimal volumetric shrinkage defects.

The physicochemical nature of the technical solution to achieve the problem is as follows: a cullet, ground together with a pore former, granular and hydrophobized, due to its low bulk density (450 ... 470 kg / m ³ ) and occupying the volume of the raw material mass, forms the porous structure of the raw material, and due to the hydrophobization of the surface of the granules and the presence of a layer of water repellent, the treated granule has a smoothed (and ideal - spherical and egg-shaped) surface, inside which a relatively loose glass m is enclosed Assa. For this reason, the raw structure has all the prerequisites in the firing process to form the correct spherical vitrified closed pores from the inside.

The presence of uniformly distributed, mainly spherical and egg-shaped, vitrified closed pores throughout the volume of the ceramic product can significantly increase the ability to withstand the applied mechanical loads in comparison with ceramic products of the prototype, where the pore shape has angular edges and uneven surfaces, contributing to the creation of stress centers in the presence of mechanical loads. It is known that the spherical surface of the pores can significantly reduce the density, and therefore the thermal conductivity of the resulting wall and facing products obtained by the present method, while maintaining the strength characteristics.

Hydrophobized granules, having low adhesion to the clay component and to each other, make the raw material mass of the charge easy to move and easy to lay, i.e. plasticize it and with a plastic molding method, much less effort is required for a belt screw press (first option). Cullet, ground together with a pore former, granular and hydrophobized, is at the same time a cleaner of the charge to a much greater extent than the grains of raw vermiculite and the filler in the charge according to the prototype, because it does not absorb water, decreasing the water solubility of the mixture from 21.8 to 13.7% (the first option), which leads to a decrease in shrinkage phenomena during drying of the raw material.

According to the second option, the hydrophobized granules also plasticize the raw mix for this reason so much that semi-dry molding requires much less effort - up to 2 ... 5 MPa. Cullet, ground together with a pore former, granular and hydrophobized, at the same time is also a cleaner of the charge to a much greater extent than the grains of raw vermiculite and the filler in the mixture according to the prototype, because does not absorb water, reducing its water solubility from 16.5 to 7-13%, which also leads to a decrease in shrinkage phenomena when drying raw.

When firing, the organic water repellent burns out with an exothermic effect at 450 ... 480 ° C, contributing to the accelerated preparation of raw material for firing. It is known that when it reaches 820 ... 850 ° C, the glass powder softens, and carbon dioxide is released from the blowing agent during decarbonization, which porosizes the glass mass of the granule. This process, which takes place in a pore that has a smooth, spherical or ovoid shape, creates a uniform bursting effect, which actively prevents the occurrence and development of fire shrinkage of wall ceramic products in the heat treatment process. With a further increase in temperature, the glass passes into the liquid phase and actively interacts with clay particles over the entire pore surface (proved by microscopic and petrographic studies). By this time, the clay component of the mass creates a strong structural skeleton of the material, which secures the almost non-shrink structure of the product. The authors found that the high density of vitrified pore walls formed at a temperature of 950 ° C by the interaction of clay particles adjacent to the pores with molten glass phase from the material of glass granules determines the high performance characteristics of the obtained wall ceramic products. When cooling, increasing the viscosity, these hardened areas, evenly distributed over the volume of the obtained ceramic products, prevent crack formation, this explains their high strength and low water absorption even with a significant decrease in the density of the finished products compared to the prototype. Ensuring uniform closed porosity of spherical and egg-shaped in ceramic products also leads to a decrease in the thermal conductivity by almost 25 ... 30% compared with the prototype.

A method of obtaining wall ceramic products according to the prototype, including the use of vermiculite, or hydrophlogopite, or hydrobiotite grains with a size of not more than 2 mm and in an amount of 2-42 wt.% Does not allow to achieve a high result, implemented in the inventive method, because the expansion of these particles occurs due to the loss of water molecules located in the interplanar spaces of these mica. This process occurs at temperatures of 540 ... 680 ° C, i.e. in the temperature range in which fire shrinkage of clay materials has not yet been observed, the liquid phase is practically absent, which means that the compensation of heat shrink phenomena does not occur (Tables 3, 4; mixture 25). The angular shape of hydromica grains contributes to the formation of local stresses in fired ceramic products.

Obtained by the present method wall ceramic products have good decorative characteristics.

Using the proposed variants of the method for manufacturing wall ceramic products in the building materials industry will also solve the problem of recycling large amounts of non-biodegradable waste - cullet of container, sheet, ampoule, kinescope and other glass, and this technology is not demanding on the purity of the starting materials.

Claims (5)

1. A method of manufacturing wall ceramic products, comprising mixing ground clay with an exhausting and intumescent additives, moistening, molding raw products in a plastic way, drying and firing, characterized in that as the exhausting and intumescent additives use glass cube, ground together with a pore former, granular and gidrofobizirovanny with a particle size of 0.1 ÷ 2.0 mm in the following ratio of components, wt.%: Cullet, ground together with a blowing agent, granular and hydrophobized 3 ÷ 30 Clay Rest calcium or magnesium carbonates or a mixture thereof is used as a blowing agent, its amount in granules is 1 ÷ 6 wt.% cullet, and the amount of water repellent is 1 ÷ 10 wt.% cullet. 2. The method according to claim 1, characterized in that the surface of the granular cullet smoothed with a hydrophobizer with a pore former has a spherical or ovoid shape. 3. A method of manufacturing wall ceramic products, including mixing ground clay with exhaust and intumescent additives, moistening, molding raw products, drying and firing, characterized in that the molding of raw products is carried out by semi-dry pressing, and glass and cullet are used as exhaust and intumescent additives, ground together with a pore former, granular and hydrophobized with a granule size of 0.1 ÷ 2.0 mm in the following ratio of components, wt.%: Cullet, ground together with a blowing agent, granular and hydrophobized 3 ÷ 30 Clay Rest calcium or magnesium carbonates are used as a blowing agent, or a mixture thereof, its amount in granules is 1 ÷ 6 wt.% cullet, and the amount of water repellent is 1 ÷ 10 wt.% cullet. 4. The method according to claim 3, characterized in that the semi-dry pressing is carried out at a specific pressure of 2-5 MPa. 5. The method according to claim 3, characterized in that the surface of the granular cullet smoothed with a hydrophobizer with a pore former has a spherical or ovoid shape.