RU2004518C1 - Method and ceramic feedstock for making building articles - Google Patents

Abstract

The invention relates to the building materials industry and can be used in the manufacture of bricks, ceramic stones, tiles, large blocks. Ceramic mass is prepared by mixing powders of clay, slaked lime, sand and mixing them with a solution of caustic soda to a molding moisture content of 16-22%. The products are molded in plastic and heat treated. The latter includes the stage of thermal moisture treatment and drying. Heat and humidity treatment is carried out by gradually heating the products to a temperature of 110-120 ° C for 2 to 3 hours and then steaming them at the specified temperature for 8 to 10 hours. Drying is carried out at the same temperature for 2 to 3 hours. dry components in the ceramic mass are in the following ranges, wt.%: clay 40 - 70; sand 17-50; slaked lime 6-17; caustic soda 2-4; clay rest. 2 SPFs, 1 tabd

Description

And the acquisition relates to the industry of materials and can be used in the technology of manufacturing, molded products, for example, brick, stone, tile, 1, orion blocks,

  , a second method of making construction, which consists in the preparation of pulp and pulp, the formation of estates in a plastic way, their drying and subsequent calcination. The main raw material l, l for the preparation of the ceramic mass in the specified method is clay, in which iodine is treated with exhaust and burnable additives. Compound additives (silica sand, chamotte, etc.) reduce shrinkage and internal curing during drying and firing. Dusty tseodode fuel (anthracite, coke, hg) g-saws, etc., are used as Ogory additives. Burnout additives and f: force the roasting process, improves g 14 carriage. mass, which increases the output of t). rnrouoro products.

,,. (. „GVRKNOY operation of the well-known iv ij, -,. 1gs: the operation of firing the form g-.i1 with ZORLMR With this circumstance oi. I. g, HL and its disadvantages: high cost-price (of a single product. High zig1t ex.: state of technology (crimping temperature 1000 ° C) not only increases the cost of finished products, but it also causes certain environmental problems, a decision and “kg then DUX also leads to the cost of the product.

August 1, a method for the manufacture of building products, including the preparation of a ceramic mass by mixing clay powders, thinning and active additives, and for creating them with an active solution, molding plastic products and heat treating them. The heat treatment process consists in the fact that the molded products are dried and mature before final shrinkage at a temperature of 40-65 ° C for 2-4 hours, are subjected to heat and humidity treatment in a closed atmosphere of saturated vapors at a temperature of 90-105 ° C for 4-24 hours and then dried at a temperature of 120-130 ° C with a gradual decrease in humidity and then a drying open atmosphere for 2-12 hours. Generally, the general continuation of all phases is between 18 and 36 hours. quartz dog, for example k, in kaiestve active additive chrprimeo, slaked lime, as Ak tyumogo solution, such as caustic yes. In this case, the optimal amount

each component is selected based on the specific surface of the active clay fraction, determined by the absorption of the blue color of methylene.

The absence in this method of the operation of high temperature firing significantly reduces the cost of the finished product, improves the environmental performance of production. However, the disadvantage of products made from the specified ceramic mass according to the indicated technology is their insufficiently high strength. The product manufacturing cycle is long.

The aim of the invention is to increase productivity and improve the physicomechanical properties of finished products. This goal is achieved by the fact that in the method of manufacturing building products by preparing a raw ceramic mixture by mixing clay powders, aggregate, slaked lime and mixing the lime hardener activator with an aqueous solution to obtain a plastic mixture, molding the products and heat treating them in two stages - heat and moisture treatment in closed atmosphere of saturated steam and subsequent drying with a gradual decrease in humidity, thermo-humidity treatment is carried out by uniform heating of products temperature of 110-120 ° C and steaming at said temperature for 8-10 hours and drying is carried out at the same temperature for 2-3 hours.

The raw ceramic mass contains clay, sand, slaked lime and a lime hardening activator caustic soda in the following ratio of components,% by dry weight:

sand17-50

slaked lime 6-17

caustic soda 2-4

clay clay

The invention is carried out as follows.

Clay from the quarry enters the clay shovels by a conveyor belt and is fed to stone separating rollers, where it is freed from large solid inclusions. Then, in a drying drum, it is dried to a moisture content of 3% and fed to a mill, where it is milled to a specific surface of 3500-5000 m2 / kg. After grinding powder clay, the elevator is fed to the clay feed hopper. Active additives, slaked lime is also dried and, if necessary, grinding in

mill and fed into the feed hopper of the active additives.

The dry components from the supply hoppers are dispensed in the required proportion by the conveyor belt to the mixer (clay mixer), where an active solution of Ma2CO3 is fed from the supply containers by the liquid dispenser. The molding moisture content of the resulting mixture is 16-22%.

The raw ceramic mass prepared in the mixer is fed by a belt conveyor to the fine grinding rollers and then to the vacuum press. A clay bar molded by a press is cut with a cutting machine into products that are loaded onto special pzlets in cassettes. Cassettes with a crane beam are loaded into chambers of batch heat treatment. The load factor of the cameras by volume should be 0.5-0.75. In the chambers, the energy carrier is forcedly circulated (superheated water under pressure) in a closed circuit: heat exchanger - working area - heat exchanger.

According to a given program, the products are uniformly heated for 2-3 hours in a closed chamber atmosphere to 110-120 ° C with a heating rate not exceeding 60 ° C / h. Then, they are kept at this temperature for 8-10 hours in a saturated vapor-air medium formed in the chamber during the heating of the products. Excess moisture is slow (not more than 10% / h is discharged from the chamber).

Subsequently, moisture is removed from the chamber within 2-3 hours by smoothly replacing the vapor-air medium of the chamber with dry air, while maintaining a temperature of 20 ° C in the chamber. When the humidity in the chamber is reduced to 3% RH, the heat supply to the chamber is stopped and it is damped to a temperature of 70 ° C by supplying atmospheric air into it and removing heated in the chamber. The cooling rate of the products should not be higher than 50 ° C / h. After the products are cooled to the indicated temperature, the chambers are opened, the products in the cassettes are unloaded by a crane-beam to the finished product site, where they are removed from the cassettes and sent to the finished product warehouse.

The table shows examples of specific compositions (dry components) of raw ceramic mixtures and properties of products obtained on their basis by the specified technology.

The optimum composition (Example 14) corresponds to a high material strength, a sufficiently high coefficient of water resistance and good ductility, which is a prerequisite for extrusion, especially of large products, which takes place in this technology.

Compositions with an upper limit on clay (example 1) and simultaneously with limit values on slaked lime and caustic soda (examples 9,10) have lower compressive strength and low coefficient of water resistance, which determines the limits of the content of these components.

The upper limit of the sand content (example 3) and the lower limit of the clay content (examples 2, 3) are due to a decrease in the ductility of the mass, a decrease in the amount of cement and, as a consequence, a decrease in the strength of the material. At the same time, the lower limit on sand (examples 4, 9) sets the minimum amount of scrubbers, a further reduction of which leads to an increase in the number of cracks in the products during heat treatment and, accordingly, to an increase in the percentage of rejects.

The limit value of the content of slaked lime, equal to 17% (Example 5), is dictated by the high cost of this component, as well as the absence of a significant effect of a further increase in its content on the properties of the finished products.

The minimum content of slaked lime (Example 6) and caustic soda (Example 8) is determined by a decrease in the strength characteristics and water resistance coefficient of the products.

The maximum caustic soda content (Example 7) is limited by the appearance of efflorescences on the surface of the products, as well as by the cessation of further improvement of material properties.

Compared with the prototype, building products made according to the proposed method from the proposed ceramic mass have higher strength, and it is possible to increase the productivity of the process itself.

(56) Zorokhovich B.C. et al. Brick production. L., Stroyizdat, 1988, p. 6-8.

French Patent No. 2572723, cl. From 04 to 33/00, publ. 1986.

Claims (2)

1. A method of manufacturing building products, including the preparation of a raw mixture by mixing clay powders, aggregate - sand, slaked lime, and mixing an lime mortar activator with an aqueous solution to obtain a plastic mixture, molding the products and their heat treatment in two stages, heat-moisture treatment in a closed atmosphere saturated steam and subsequent drying with a gradual decrease in humidity, characterized in that, in order to increase productivity and improve the physical and mechanical properties of the finished products, Moisture-and-moisture treatment is carried out by uniformly heating the products to 110 - and steaming at the indicated temperature for 8 to 10 hours, and drying is carried out at the same temperature for 2 to 3 hours. 2. Raw ceramic mixture for the manufacture of building products, including clay, aggregate - sand, slaked lime and lime hardening activator - caustic soda, characterized in that it contains the specified components in the following ratio,% by dry weight: Sand17-50 Slaked lime6-17 Caustic Soda 2-4 Clay else