SU833828A1 - Method of brick leaching based on red-annealed clays - Google Patents

Description

; 54) METHOD OF BLEACHING A BRICK ON A BASIS OF RED BLOODY CLAY.

one

The invention relates to building materials and can be used in the manufacture of coarse ceramics, such as bricks, stones, etc.

A known method of bleaching bricks based on red-clad clays by introducing 20–30 wt.% Of lime into the mixture of finely ground limestone.

The disadvantage of this method is that carbonate rock — limestone, recommended for siphoning red clay — is a relatively expensive addition to the brick mix, which to a lesser extent bleaches clay and serves as the main raw material for the production of lime, portland cement and its varieties.

The closest to the proposed method is the method of bleaching bricks based on redox clay, with the introduction of a brightening carbonate-containing additive into the mixture (chalk, dolomite marl, slaked lime, etc.) 15-50% 2,

The disadvantage of this method is the insufficient degree of whitening, the appearance of efflorescence on the surface of the brick and the high cost of the additive.

The purpose of the invention is to increase the degree of whiteness, eliminate efflorescence on the surface of a brick and reduce the cost of the latter.

This goal is achieved by the fact that in the method of bleaching bricks based on redox clays by introducing into the mixture a brightening carbonate-containing additive 10-20 wt.%,

As a brightening additive, waste of asbestos-cement production is introduced - sediment in recuperators.

Sample preparation is performed as follows.

The clay is dried at 70-80s,

5 are crushed manually with a wooden mallet and sieved through a sieve with a cell side size of 2 Mf-i. Asbestos-cement waste is dried

0 at the same temperature and manually powdered.

The components are metered by weight, mixed by hand until a uniform color powder is obtained. Then the powdered dry blended mixtures are moistened to a ductile state, followed by drying for 48 hours.

Samples of size (20 mm, 50 x 50 V mm and mm are made by plastic molding.

dried to constant weight and calcined at 800-1000 ° C with an interval of one hour at the maximum temperature.

Properties of the samples are given in table. one. . .

In addition, waste from asbestos-cement production (precipitation in recuperators) as compared with carbonate additives (chalk, lime is more intense whitening ability. The test results are shown in Table 2.

The increased intensity of bleaching of red clays with waste from asbestos-cement production (precipitation in recuperators) compared to carbonate additives is explained by the exceptionally high dispersion of waste particles approaching colloidal particles, except for 9-10% of short asbestos fibers, while the waste forms plastic dough moisture content (absolute) of 100% and ease of monotronic process of dehydration of amorphous calcium hydrosilicate and chrysotile asbestos, as well as complete completion of the processes of formation calcium ferrite and other minerals and the shift of the bleaching processes of red clays towards lower temperatures due to the high dispersion of waste particles and the large reactivity of dehydration products

If 6–22% CaO is introduced with the dosage of lime or chalk in the amount of 10–40%, only 2–6% CaO s, 5–15% waste is required for equivalence of the color of the crock. What

one

9d 85 80

ten

15

20

Clay

Known 20th 20

concerns the clarification of red clays, then, it is caused by the formation of dicalcium ferrite 2CaO-Fe20, and monocalcium aluminate, monalcium mullite silicate and other crystalline phases, i.e. the intensity of the binding of calcium oxide to iron oxides, and silicon. When using carbonate bleaching additives (limestone or chalk), the process of assimilation, the binding of calcium oxide, proceeds very slowly and does not end completely even at 1450s.

The foregoing is confirmed by the fact that a brick bleached with carbonate additives forms fading during operation. As for the brick, whitened with asbestos cement production waste, it does not form efflorescence, which indicates the complete binding of calcium oxide at 1000 ° C.

Consequently, waste from asbestos-cement production (precipitation in recuperators J as a bleaching additive does not give any fading on the surface of the brick, which is their advantage over other carbonate-containing additives — lime and chalk.

When using asbestos-cement production wastes as a bleaching additive instead of limestone or chalk, the cost of the bleached brick decreases, since the cost of waste is 5 times lower than finely ground limestone and 12.5 times lower than finely ground chalk.

Table 1

9.1

73 63

325

9.0 / 268 212

54

8.9

374 6.3

table 2

Claims (1)

Claim The method of bleaching brick based on red-burning clays by introducing into the mixture a clarifying carbonate-containing additive in an amount of 10-20 wt.%, Characterized in that, in order to increase the degree of whiteness, eliminate fading. On the brick surface and reduce the cost of the latter, they are introduced as a brightening additive asbestos-cement production waste - sediment in recuperators.