LT5923B - Ceramic composition with frost resistance and process for preparing thereof - Google Patents

Abstract

The present invention relates to construction industry, in particular, ceramic masonry (clinker bricks, floor blocks). The ceramics claimed is characterized by low water absorbtion and high frost-resistance and can be exploated at a harsh environment conditionswhen masonry or its elements due to climaticconditions are subjected to long lasting effects of water absorbtion and fluctuations of temperature. The invention claimed aims to increase the compressive strenght and frost-resistance of ceramics made of fusible clay. The composition of formation mixture is as follows: fusible illitic clay - (70-90) %, thining additive -melt of mineral wool proccessing waste - (10-30) %. Semi-manufactures made of formation mixture are subjected to burning at (1060 ±5) oC. Ceramic masonry elements obtained are characterized with low water absobtion, high frost -resistance and durability.

Description

The invention relates to the field of construction industry, namely to the production of ceramic masonry products and finishing products (clinker bricks, floor tiles). Such ceramics have low water absorption and high frost resistance and can therefore be used in severe corrosive environments where the masonry or its elements are soaked by climatic conditions (prolonged rain, ground water) and exposed to changes in refrigeration and thawing, but are not effectively protected.

Frost-resistant ceramics (GB2379658) are known for use in aggressive environments. It is stated that a multicomponent molding mixture is used to obtain such ceramics: clay (60-70)%, lean sand (5-10)%, also other additives ceramic scrap (9-12,5)%, ground glass (10-20) )%, anthracite (5-10)%. The molding mixture is fired at (1100-1150) ° C for 96 hours. However, frost resistance is not specified.

Leen Yu (Patent CN101229972) discloses the composition of frost-resistant ceramics: clay (60.7-77.7%), touching sand (22-39%) and feldspar (0.1-0.3%). The molding mixture is combusted at very high temperatures (115 ° C-138 ° C), and therefore the production of such ceramics requires high energy resources.

High-melting clays can also be lean using technogenic raw materials. V. Abdrakhimov (patent RU23 89706) states that ceramics are obtained by burning a molding compound from a light-melting, illite clay leached with a technogenic raw material, the gabbro-diorite charge of mineral wool. The main clay mineral is hydro-mica (ilite). The composition of the forming mixture is as follows: easily melting clay (70-90%), touching additive mineral wool gabbro-diorite charge waste (10-30%). The humidity of the forming mixtures is 20-24%, the burning temperature - 1050 ° C. However, the obtained ceramics exhibit high water absorption (10.2-12.4%) and frost resistance up to 60 cycles. This patent was chosen as an analogue.

Patent RU2388723 states that light-melting clay can be leached from the waste of diabetic mineral wool. The diabetic charge waste contains a high content of Fe2O3 (13.4%), which not only loses the formation mixture, but also intensifies the sintering process. Composition of the molding mixture: lightly melting clay (70-90%), touching additive - mineral wool diabase loading waste (10-30%). The disadvantage of the patent is that the ceramic obtained has low frost resistance (50-62 cycles).

R. Mačiulaitis (patent LT 2010046A) described frost-resistant ceramics, which are characterized by sufficiently low water absorption (<3%). Light melting clay (76-84%), sand (12-18%) and chipping (4-6%) are used to prepare the forming mixture. It is stated that the combustion of the ceramic mixture is carried out at a temperature of 1075-1090 ° C. The predicted frost resistance is 1000 cycles. Patent deficiency - frost resistance is determined by a rapid rate detection method, which has the disadvantage of high error rates, and fracture resistance by valid experimental (in-kind) methods that accurately estimate durability.

The object of the invention is to increase the compressive strength and frost resistance of ceramics made of light-melting clays.

This objective is achieved by the fact that the easily melting clay, whose primary mineral is hydro-mica (ilite), is lean with a technogenic raw material - the waste from the melting of mineral wool. The clay of the Dysna site, which is classified as a mild group of mild plasticity, has a clay particle fraction of 70-90%. Clay is characterized by low carbonate content (0.004%). The chemical composition of the clay is given in Table 1.

table. Chemical composition of clay

Clay name Chemical composition, % S1O2 A1 ₂ O ₃ + TiO ₂ Fe ₂ O ₃ CaO MgO Na ₂ O + K ₂ O Injuries Dysnos 51.80 18.43 7.17 4.70 3.27 4.00 9.33

The essence of the invention is that the clay leaching waste from mineral wool melt consists of melt particles (beads) and mineral wool fibers. They must be crushed and sifted. Their bulk modulus is 1.83 and the granulometric composition is given in Table 2. The mineral wool fibers in the waste reinforce the ceramic comb, which increases the compressive strength and frost resistance.

table.

Raw material Residues on sieve Fraction size, mm - particle content,% Large size module 2 1 0.5 0.25 0.125 <0.125 Wastes from mineral wool melting Partial 0.29 3.92 19.62 39.55 26.84 9.79 1.83 Full 0.29 4.21 23.83 63.37 90.21 -

70-90% clay and 10-30% mineral wool melt blasting residues were used to prepare the forming mixture. The compositions of the formation mixtures are given in Table 3. Moisture content of molding compounds is 20-22%. The semi-finished products are plastic formed, dried to constant weight and burnt at 1060 + 5 ° C using the best combustion mode. The basic physical mechanical properties of ceramic products are given in Table 4.

table.

Forming blend Raw material Clay Wastes from mineral wool melting 1 90 10th 2 80 20th 3 70 30th

table.

Forming mixture Density of ceramic comb, kg / m ³ Water absorption,% Compressive strength, MPa Resistance frost, set one-sided refrigeration thawing way), cycles 1 2160 1.2 35 > 300 2 2140 1.5 44 > 300 3 2080 2.5 31st > 300

Frost-resistant ceramics are obtained as follows:

1. Preparation and storage of light-melting clay;

2. Preparation of slimming additive - crushing and sieving;

3. Mixing of raw materials, preparation of required moisture forming mixture;

4. Formation and drying of ceramic semi-finished products;

5. Combustion of ceramic products using the best combustion mode.

Frost resistance was determined in accordance with LST EN 1985: 2006 and LST CEN / TS 772-22: 2006 (one-way freeze-thaw method). Ceramic products have good physical and mechanical properties and durability and can therefore be used under severe environmental conditions. Ceramic products are fired at 1060 ° C, which reduces energy consumption. The use of a technogenic additive makes it possible to recycle waste, protect the environment and expand the base of raw materials used in the production of ceramic products.

Claims (4)

Definition of the Invention 1. Frost-resistant ceramic, consisting of light-melting illite clay and lean additive (mineral wool melt leaching waste), characterized in that it contains 70-90% clay and 10-30% lean additive - mineral wool melt leaching waste . 2. The frost-resistant ceramic of claim 1, wherein the loosening additive used to leach the clay (debris from mineral wool melting) consists of melt particles (beads) and mineral wool fibers. 3. Frost-resistant ceramic according to claim 2, characterized in that the touching additive must be crushed and screened. 4. A method for obtaining frost-resistant ceramics, which comprises the preparation, mixing, shaping and combustion of clay and flint additive, characterized in that the ceramic products are fired at a maximum temperature of 1060 ± 5 ° C.