RU2664288C1 - Ceramic mixture - Google Patents

Abstract

FIELD: ceramics.

SUBSTANCE: invention relates to compositions of a ceramic mass for production of bricks of construction series of predominantly solid bodies. Ceramic mass, including loam and claydite clay, differs in that it additionally contains a slag, fine chalk (technological – waste of mineral fertilizers production) and technical water – waste of the pulp industry with the following ratio of components, mass. %: loam 59–59.5, expanded clay 19–19.5, granulated slag fr. 0.14–0.316 14.5–15, fine chalk with specific surface area 3,000 mc²/g 4.5–5, technical water – waste from the pulp industry, with density 1.013 g/cm³ 1–3.

EFFECT: increase strength, frost resistance of products and absence of external defects.

1 cl, 4 tbl

Description

The invention relates to compositions of ceramic masses and can be used for the production of building bricks ordinary ordinary solid.

The known composition of the ceramic mass shown in the patent of Russia No. 2300507 IPC SB04/1/132, approx. 06/10/2007, and, including components at their ratio, mass. %:

- Loam 67.84-68.15 - Expanded clay 15.25-20.86 - Iron-containing waste - fine sediment from cyclones 8-14,46 - Osprey (dry) 2.14-3.3

Along with the great advantages of the known composition of the ceramic mass, specifically: the architectural appearance is increased, two types of waste are utilized, the degree of general shrinkage is reduced, there are disadvantages:

1. The process of plastic formation of hole bricks is complicated, due to the sticking of cellulose-fibrous particles of osprey to the core surface;

2. Low strength of dried bricks (3-4 MPa), which contributes to the increase of marriage during transportation of dry bricks to the firing workshop;

3. The production technology is becoming more complicated as the “osprey” must first be dried, due to the fact that the humidity in its dumps is up to 60%, respectively, the heat and energy costs increase;

4. A relatively high firing temperature (1000 ° C);

5. Insufficient strength for the manufacture of perforated bricks - 31.5 MPa.

There is a second composition of the ceramic mass described in Russian patent No. 2455257 IPC С04В 33/00, approx. 04/27/2011, and, including components when their ratio in mass. %:

- Fusible clay raw materials 91-98% - Technological chalk 2-9%

This composition has a number of positive qualities:

- increase frost resistance of the finished product by creating a reserve porosity;

- increasing the strength of the finished product.

The disadvantages of this composition include:

- semi-dry pressing brick production technology is more expensive than plastic molding;

- Achieving high quality end products is possible only using high-quality fusible raw materials.

The closest composition to the technical solution is the composition given in the patent of Russia No. 2371417 С04В 33/132, approx. 04/20/2009, and including in the masses. %:

- Loam 60-85% - Expanded clay 15-40% - Sediment from filters from deferrization of fresh water  over 100% 0.015-1.3%.

The specified ratio of the components of the ceramic mass of this patent provides a content of Al ₂ O ₃ in the range of 13.4-14.5 mass%, and Fe ₂ O ₃ 6.8-7.6 mass% per calcined substance.

Along with the advantages of the known composition (iron-containing waste from fresh water treatment is utilized, strength after firing is increased by 31.5 MPa, the coefficient of structural quality is increased, shrinkage is excluded).

There are also the following disadvantages:

1. The content in the mass of expanded clay clay of more than 25% leads to swelling of the samples, since the recovery reaction of the process during firing is clearly manifested.

2. The iron-containing precipitate from the Fe (OH) ₃ filters during the firing process passes into Fe ₂ O ₃ , and the hydroxyl ions (OH) ₃ pass into water vapor and penetrate the mass, which leads to a decrease in frost resistance and limited use for face bricks.

3. Expanded clay contributes to the formation of cracks during drying, and the compressive strength after drying decreases and does not exceed 2.5-3 MPa, since clay shrinkage is different, which increases losses during the transportation of bricks from the drying workshop to the firing workshop, especially if% content expanded clay clay in the composition of the mass exceeds 25%.

4. Insufficient frost resistance of 15-16 cycles.

The objective of the invention is to increase strength, frost resistance and reduce the formation of cracks in ceramic brick full.

This object is achieved in that the ceramic mass, including loam and expanded clay, is characterized in that granulated clay is additionally introduced. The ceramic mass, including loam and expanded clay, is characterized in that additionally introduced granulated clay, finely divided technological chalk - waste from the production of mineral fertilizers and process water - waste the pulp industry in the following ratio of components, mass%: Ceramic mass, including loam and expanded clay, is characterized in that it but granulated slag, fine industrial chalk - waste from the production of mineral fertilizers and industrial water - waste from the pulp industry in the following ratio of components, wt% were introduced, fine micron technological - waste from the production of mineral fertilizers and industrial water - waste from the pulp industry in the following ratio of components, mass% :

- Loam 59-59.5 - Expanded clay 19-19,5 - Granulated slag fr. 0.14-0.316 14.5-15 - Fine technological chalk - waste fertilizer production with a specific surface of 3000 cm ² / g 4,5-5 - Industrial water - pulp production waste

industry, with a density of 1.013 g / cm ³ 1-3.

To implement the task, components with the following properties were used:

1. Loam of the Osinogorsk deposit (Tula region). By granulometric composition, 1 layer of loam is characterized by the composition: clay particles 10%, sand 60%, silty 30%. The 2nd layer of loam is characterized by the composition: clay particles 6%, sand particles 40%, dusty 55%. Raw materials are low in the number of coarse inclusions with a predominance of small sandy-stony and carbonate inclusions. This raw material belongs to the sour group. Loams are non-sintering, low melting, moderately plastic raw materials (plasticity number 10–13), with the exception of the second layer, it is low plastic (plasticity number 3-5). Loam water absorption of 13%, compressive strength of 81-134 kg / cm ² , with a bend of 29-44 kg / cm ² (at a temperature of 950-1000 ° C). The color after firing is red. According to the chemical composition, loams are characterized by the following content of components,%: SiO ₂ - 69.21-78.5, A1 ₂ O ₃ - 8.89-13.95, Fe ₂ O ₃ -3.24-5.47, CaO - 0.65-2.85, MgO - 0.6-1.7, SO ₃ - 0.2-0.18, Na ₂ O -0.57-1.06, K ₂ O - 1.72-2 , 92, TiO ₂ - 0.1-0.2, p.p.p. 3.11-5.34.

2. Expanded clay is a highly dispersed clay, the composition of which is dominated by small parts (less than 0.001 mm), and their amount varies from 35 to 83%. Clay is slightly calcareous, medium plastic, the plasticity number is 17.8-25.7. In terms of refractoriness, clay refers to fusible less than 1350 ° C. The expansion coefficient varies from 2.5 to 5.0. The temperature of the start of expansion is 970-1150 ° C. Water absorption ranges from 3 to 7%. The compressive strength is 36–40 MPa. The chemical composition is presented in table 1.

3. Granulated blast furnace slag in accordance with GOST 3476-74, which is a waste product of PJSC Tulachermet located at the address: Russia, Tula Region, Tula, ul. Przhevalsky 2. Granulated slag in its chemical composition must satisfy the following requirements:

content of silicon dioxide (SiO2),%, not less 38 the content of the sum of calcium oxide (CaO) and oxide magnesium (MgO),%, not less 43 phosphorus pentoxide content (P2O5),%, no more 2.5. The average density is 900-1000 kg / m ³ fraction - 0.14-0.316.

4. Fine technological chalk - according to TU 2144-028-00206486-2008, grade A, in accordance with GOST 12.1.005 belongs to the 4th hazard class, according to GOST 12.1.007, the substance is low-hazard. The content of calcium carbonate, magnesium, strontium in terms of CaCO3 is 94.6%. Mass fraction of water - 0.18%. Mass fraction of ammonium nitrate - 0.16%. The mass fraction of substances insoluble in hydrochloric acid is 0.8%. Mass fraction of total iron in terms of Fe2O3 - 0.13%. Mass fraction of phosphates in terms of P2O5 - 0.4%. The mass fraction of strontium in terms of Sr is 1.4%. The mass fraction of the deposit on a sieve of 1 mm is 0%. The specific surface is 3000 cm ² / g, the average density is 2700 kg / m ³ .

5. Industrial water - waste in the production of toilet paper at the company LLC "SSC Hygin Products Russia" branch in the city of Sovetsk, Tula region.

pH = 7.58, suspended solids 10.8 mg / l, density - 1.013 g / cm ³ .

The chemical composition of industrial water is presented in table 2.

The composition of industrial water contains the mineral kaolinite (Al ₂ O ₃ * 2SiO ₂ * 2H ₂ O) - 1-3%.

Example 1

A method of obtaining a ceramic mass is as follows: experiments were carried out on the implementation of the compositions of the ceramic mass using dry components, given by weight in table. No. 1.

In total, ten batches of molding materials were prepared.

For this, the following components of composition No. 2, shown in table No. 3, were dosed by weight. They took 443 g (59.1%) of loam and 143 g (19.1%) of expanded clay, finely ground, and then mixed them until smooth. Then, 110 g (14.7%) of granulated slag of a fraction of 0.14-0.316 mm was added to the resulting mixture and mixed thoroughly until a homogeneous state. The resulting mixture of the three components was moistened to a moisture content of 20%, 35 g (4.7%) of finely divided technological chalk with a specific surface of 3000 cm ² / g was moistened with technical water 18 g (2.4%) with a density of 1.013 g / cm ³ to a moisture content of 20% . Then all the components were mixed until homogeneous.

A similar method was used to prepare the compositions of molding materials No. 1, No. 3, No. 4, No. 5, shown in table No. 3.

From the resulting mass, the compositions were molded (Table 3). Samples were cylinders of 50 × 50 mm under a specific pressure of 2.5 MPa. Samples were dried at a temperature of 75 ± 5 ° C for 66 hours. Three samples of each batch were tested for strength after drying, and the rest were fired in a ring furnace at a maximum temperature of 960 ° C. After firing, the samples were visually examined for defects (cracks, swelling, pigmentation), the average density, strength, and frost resistance were determined by standard methods and GOSTs. The test results are shown in table 4.

Analysis of the test results of the properties of samples of ceramic mass, are given in table. No. 4 shows the following:

1. Compounds No. 1 and No. 5 are not recommended since do not meet the task of the presence of defects;

2. According to the results of testing the samples, it was found that the optimal ceramic mass result, in comparison with the prototype, are compositions No. 2, No. 3, No. 4, which corresponds to GOST 530-2012.

The physico-chemical nature of the achievement of the task is as follows:

1. Calcium-containing component (fine chalk technological) during the firing of clay material montmorillonite (A1 ₂ O ₃ * 4SiO ₂ * Н ₂ O * nН ₂ O) and glauconite (K ₂ O * Fe ₂ O ₃ * 4SiO ₂ * 10H ₂ O) it affects the crystallization process - it contributes to an increase in the content of CaO * Al ₂ O ₃ * 2SiO ₂ and 2CaO * Al ₂ O ₃ * SiO ₂ , that is, crystalline phases that increase the strength of the ceramic crock. In this case, the effect of finely divided technological chalk is manifested only under the condition of homogenization of the ceramic mass.

2. An increase in the frost resistance of a ceramic crock with the introduction of components (finely divided technological chalk, gravel slag and industrial water) ensures the creation of a favorable structure in the firing process, from the point of view of frost resistance, that is, it is characterized by a large number of reserve pores and the best opportunity for moisture migration during ice formation.

Claims (2)

Ceramic mass, including loam and expanded clay clay, characterized in that it additionally contains gravel slag, finely divided technological chalk - waste from the production of mineral fertilizers and industrial water - waste from the pulp industry in the following ratio of components, wt.%: Loam 59-59.5 Expanded clay 19-19,5 Granulated slag fr. 0.14-0.316 14.5-15 Fine technological chalk - production waste fertilizers with a specific surface area of 3000 cm ² / g 4,5-5 Process water - a waste of pulp production industry, with a density of 1.013 g / cm ³ 1-3.