SU435209A1 - METHOD OF OBTAINING CERAMSITE - Google Patents

Description

,one

The invention relates to the production of porous aggregates for concrete and structures based on them.

A known method for producing expanded clay includes molding, processing a semi-finished product with an aqueous suspension of clay and firing.

The disadvantage of this method is the low strength of expanded clay gravel.

The aim of the invention is to increase the strength of expanded clay gravel.

This is achieved by the fact that the semi-finished product is treated with an aqueous solution of phosphate.

Increased strength is provided by compaction of the surface layers of the granules due to diffusion and replacement of cations creating compressive stress in the surface layer, as well as the formation of A1 and Mg-type phosphates of aluminophosphate binders with high physicomechanical characteristics. The proposed method is carried out as follows. Expanded clay granules, obtained by a known plastic method of preparing raw materials and semi-finished products, are fed with solutions of phosphorus-containing compounds before being fed to the calcination. This additional operation is carried out during the passage of the molded granules from the molding unit to the intermediate (spare) container or during the residence of the material in this container.

by irrigating or spraying the solutions used, for example with a nozzle, which provides abundant wetting of the surface of the granules. Excess solution draining from the grapules is returned to the system for reuse. Concentrated phosphate solutions with a temperature of 18–20 ° C are used for irrigation.

Subsequent drying, heat treatment, burning and cooling of the granules are carried out by methods widely used in the production of expanded clay gravel.

Example 1. From the clay raw material of the Smyshl deposit, plastic granules are formed with a diameter of 16 mm. Part of the granules are subjected to irrigation with a concentrated solution of diammonium phosphate for 10 minutes. Surplus not absorbed in

the prefabricated solution is drained into a special container and reused, and the granules after processing are transferred to a laboratory furnace, imitating the firing mode in the manufacture of expanded clay under production conditions. Another part of the granules is used to evaluate the present method: these grapes serve as controls and are subjected to heat treatment under similar conditions. Physicomechanical indicators of expanded clay

are given in table. one.

Table 1

The proposed sno.sob is simple to implement, ecdncheskrkr effective, since with a small cost of additional equipment and the use of non-deficient chemicals gives a significant increase in quality.

table 2

Example 2. Semi-finished granules are prepared in a manner similar to that described in Example 1, treated with an aluminum chromophosphate binder solution. Subsequent heat treatment are carried out in modes that simulate the process of production of expanded clay.

Physico-mechanical indicators of claydite are given in table. 2

Treatment with phosphate solutions leads to an increase in the strength characteristics of 2 to 3 times.

Subject d z about a b ete n i

A method for producing expanded clay, which includes molding, processing the semi-finished product and firing, characterized in that, in order to increase the strength of the expanded clay gravel, the semi-finished product is treated with an aqueous solution of phosphate.