RU2389708C1 - Ceramic mixture for making wall materials - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: ceramic mixture relates to compositions of ceramic mixtures for making wall materials, mainly bricks, and can be used in the industry of construction materials. The ceramic mixture for making wall materials contains clay and screenings of zeolite-containing rocks with particle size smaller than 0.31 mm, characterised by bulk weight of 960 kg/m3, density of 2720 kg/m, fire resistance 1180C, mineral composition of clinoptilolite, orthoclase, quartz, clay minerals and iron compounds of the following composition in wt %: SiO2 - 61.16; Al2O3 - 11.64; Fe2O3 - 4.82; CaO - 5.45; MgO - 1.92; R2O - 4.88; percentage of other impurities - 9.86, with the following ratio of components of the mixture in wt %: clay - 65-90; screenings of zeolite-containing rocks of particle size smaller than 0.31 mm - 10-35. ^ EFFECT: increased strength and reduced water absorption of products. ^ 1 ex, 3 tbl

Description

The invention relates to compositions of ceramic masses for the manufacture of wall materials, mainly bricks, and can be used in the building materials industry.

Known ceramic mass for the manufacture of wall materials, including clay (in wt.%) - 93.5-97.5 and quartz sand, heat-treated at 500-900 ° C - 2.5-6.5 (and.with. No. 814962 ) The disadvantage of this mass is that products based on it have high water absorption (21-22%) and have low strength - 19-25 MPa. In addition, the heat treatment of quartz sand requires additional energy costs and leads to an increase in the cost of products.

Another ceramic mass (a.s. No. 1054324), containing 70-80% clay and 20-30% of the crushing waste of crystalline shale fractions of less than 0.63 mm, does not allow to obtain ceramic materials of high strength (R _cr - 25-27 MPa).

The closest analogue to the proposed one is the mass for the manufacture of ceramic wall materials, including clay (in wt.%) - 72-90; screening of orthofira fractions less than 2.0 mm - 10-28 (A.S. 881066). The disadvantage of this mass is that products based on it after firing have low compressive strength (24-26 MPa) and high water absorption of 18-19%.

The problem to which the invention is directed, is to increase strength and reduce water absorption of ceramic wall materials.

The essence of the invention lies in the fact that the ceramic mass for the manufacture of wall materials, including clay and a filler, characterized in that as a filler it contains a screening of zeolite-containing rock fractions of less than 0.31 mm in the following ratio of mass components, wt.%: Clay - 65-90, screening of zeolite-containing rocks - 10-35.

The screening of the zeolite-containing rock is a finely ground powder of red-brown color obtained by crushing and grinding the rock upon receipt of fine-grained road filling. Bulk weight - 960 kg / m ³ , density - 2720 kg / m ³ . Refractoriness - 1180 ° С. The mineralogical composition includes clinoptilolite, orthoclase, albite, quartzite, goethite and montmorillonite. The chemical composition of screening of zeolite-containing rocks is shown in table 1.

Table 1 SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO R ₂ O p.p.p. 61.16 11.64 4.82 5.45 1.92 4.88 9.86

Shemi hydromica clay with a chemical composition including wt.%: SiO ₂ 61.22, Al ₂ O ₃ 16.24, Fe ₂ O ₃ 7.68, TiO ₂ 0.97, CaO 0.60 was adopted as a clay rock. MgO 2.58; K ₂ O 2.16; Na ₂ O 1.55; pp 6.65. Clay refractory temperature 1200 ° С. Clay is the main component providing plasticity and sintering of the ceramic mass.

From the scientific and technical literature, as well as from the well-known list of information, the applicant has not found technical solutions using screening of rocks with a low zeolite content (within 10-12%) with a significant presence of feldspars (55-60%) or with similar fillers of a similar chemical composition.

The chemical interaction of the main elements (clinoptilolite and orthoclase) of screening the zeolite-containing rock with the specified combination of oxides with the decomposition products of clay minerals leads to an earlier reaction in the solid phase with the formation of compounds such as spinels and the formation of a large amount of liquid phase due to the interaction of oxides of alkaline and alkaline-earth elements with oxides of iron, silica and alumina. Since the liquid phase is practically a cementitious substance, its formation in a larger quantity than in known compositions at low firing temperatures causes the production of artificial stone with a denser structure, which reduces water absorption and increases the strength of products.

Thus, the totality of the proposed features, according to the applicant, meets the criterion of "significant differences", acquires new properties, which consist in obtaining an artificial stone of a denser structure, which determines the strength and low water absorption of the material.

Concrete example

Ceramic masses were prepared according to a well-known technique (Knigina G.I., Vershinina Z.N., Tatski L.N. Laboratory work on the technology of building ceramics and artificial porous aggregates. - M .: Higher school, 1977. - 208 s). The dried raw materials were milled to grains of 0.63 mm. The mixture in the required proportions was thoroughly mixed dry. With the addition of water, masses were prepared with the desired molding moisture. Samples-cylinders with dimensions h = d = 40 mm were molded in a plastic way. The samples dried at 100–105 ° С were fired at a temperature of 1050 ° С with an isothermal exposure for 2 hours. The determination of water absorption and compressive strength was carried out according to GOST 13449-82 and 473.6-81. The charge composition of the masses is given in table.2.

table 2 Components Compositions I II III IV V VI Clay 95 90 80 70 65 60 Screening of zeolite-containing rock fractions less than 0.31 5 10 twenty thirty 35 40

The test results are shown in table.3.

Table 3 Composition numbers The limit of compressive strength, MPa Water absorption,% I 27.1 17.6 II 29.8 16,4 III 34.9 13.5 IV 40,2 10.7 V 43,4 8.8 VI 46.7 7.6 prototype 24-26 18-19

The test results showed the effectiveness of introducing screenings of zeolite-containing rock fractions of less than 0.31 mm in an amount of 10-35% compared with the prototype and the quartzite crushing waste. With the addition of 5% of the proposed screening, a significant increase in strength is not observed. With an increase in the content of the added additive by more than 35%, the water absorption of the samples decreases below the requirements of GOST (at least 8%). Compared with the prototype, the strength of the obtained samples from the proposed mass is more by 40-60% and water absorption is reduced. As a result of sintering of said ceramic mass, neoplasms crystallize, such as glandular spinels, anorthite, and the mullite-like phase.

The application of the proposed ceramic mass allows the following.

1. Get wall ceramic products with high strength and low water absorption.

2. To reduce energy costs for the preparation of raw materials through the use of finished finely ground additives.

3. Dispose of stone waste.

4. Thanks to the disposal of waste, environmental pollution is prevented.

Claims (1)

Ceramic mass for the manufacture of wall materials, including clay and filler, characterized in that as a filler it contains a screening of zeolite-containing rock fractions of less than 0.31 mm, characterized by a bulk density of 960 kg / m ³ , density 2720 kg / m ³ , fire resistance 1180 ° C, mineralogical composition, including clinoptilolite, orthoclase, quartz, clay minerals and ferrous compounds, chemical composition, including wt.%: SiO ₂ - 61.16; Al ₂ O ₃ - 11.64; Fe ₂ O ₃ - 4.82; CaO - 5.45; MgO - 1.92; R ₂ O - 4.88; p.p.p. 9.86 in the following ratio of mass components, wt.%:
clay 65-90 screening of zeolite-containing rocks fractions less than 0.31 mm 10-35