RU2303012C1 - Raw material mixture for production of silicate items using wastes of diamond-extractive industry - Google Patents

Abstract

FIELD: manufacture of building materials; manufacture of silicate items: bricks, stones, tiles with the use of wastes of diamond-extractive industry.

SUBSTANCE: proposed raw material mixture includes binder containing quicklime, sand and magnesium-containing wastes of mining industry at the following ration of components, mass-%: binder, 26-55; sand-filler, 45-74; binder contains the following components, mass-%: quicklime, 11.77-33.33; sand, 11.11-41.67; wastes, 37.5-73.17.

EFFECT: enhanced strength of raw material; reduced time required for autoclave treatment; reduced power requirements; increased productivity of process at retained physico-mechanical characteristics of silicate items; utilization of diamond-extractive industry wastes.

2 cl, 2 tbl, 8 ex

Description

The invention relates to the construction materials industry, namely the manufacture of silicate products: bricks, stones, tiles, etc., using waste from the diamond mining industry.

Known raw mix for the manufacture of silicate products (US 1738786, C04B 28/18, 10/15/1990), containing, wt.%: Lime 8-11; ground sand 6-12; clay 17-25; dust removal of expanded clay production 7-12; dust removal of electrode production 0.5-1; sand the rest. The disadvantage of the mixture is the complexity of the preparation of the additive.

Known raw material mixture for the production of silicate materials (RU 2077518, С04В 28/20, 04/20/1997) containing sand and slaked lime, and it additionally contains carbide lime or carbide dust in the following ratio, wt.%: Slaked lime 2-10 ; carbide lime or carbide dust 8-10; sand the rest. The disadvantages of the above mixture are the high cost of time for autoclaving and low water resistance of silicate brick.

The closest in technical essence is the raw material mixture (US 912707, С04В 15/06, 03/15/1982) for the manufacture of silicate products, consisting of a binder, including lime, sand and magnesium-containing mining waste, and sand aggregate in the following ratio of components, weight .%: lime-silica binder 10-20, sand 64-75 and ground serpentinite with S = 4900-5000 cm ² / g 5-20, while serpentinite is a product of processing of asbestos-containing rocks.

The disadvantage of the raw material mixture is the use of ground serpentinite with a specific surface area of 4900-5000 cm / g, which does not provide raw materials with a strength above 0.93 MPa and silicate products with water absorption of less than 12.6%, as well as the use of reduced autoclave modes while maintaining the physical and mechanical characteristics of silicate products at a high level: ultimate compressive strength of about 21-43 MPa and frost resistance of about 35-50 cycles.

The objective of the present invention is to increase the strength of raw materials, reduce water absorption of silicate brick, reduce time and energy costs for autoclaving, increase the productivity of the production process, while maintaining the physical and mechanical characteristics of silicate products at a high level, as well as the use of waste from the diamond mining industry and contribute to the creation of integrated technology the use of minerals from diamond deposits of kimberlite genesis instead of the existing costly, because to extract only one mineral - diamond, the content of which in the richest deposits does not exceed 3 g / t, a huge mass of rocks is processed and thrown into dumps.

This task is achieved in that the raw material mixture for producing silicate products consists of a binder, including lime, sand and magnesium-containing mining waste, and aggregate sand, according to the proposed solution, the binder contains diamond-containing mining waste as magnesium-containing waste in the following ratio of raw material components mixtures, wt.%:

astringent - 26-55;

sand aggregate - 45-74,

while the binder contains the following number of components, wt.%:

quicklime - 11.77-33.33;

sand - 11.11-41.67;

specified waste - 37.5-73.17.

Diamond mining wastes are accumulated during open pit mining of diamond deposits of the Arkhangelsk diamondiferous province (AAP) with magnesium-containing accompanying rocks, which by mineral composition are related to saponite-serpentine rocks.

The chemical composition of the waste of the AAP diamond mining industry is presented in Table 1.

Table 1 Chemical composition of waste Components SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ MgO RFP Cao AARP diamond mining waste 51.8 6.24 6 17.4 6.16 8.86

The mineralogical composition of the wastes of the AAP diamond mining industry is as follows: saponite - 61-74%; olivine - 3-6%; serpentine - 20-26%; clinoperoxene - 0.3-1.5%; grenades - 0.2-0.7%; chlorite - 0.1-0.5%; ore minerals - 0.4-1%. The mineralogical composition of serpentine wastes is represented by antigorite and chrysotile (Khvostenkov S.I. Silicate brick using serpentinite wastes / S.I. Khvostenkov, V.N.Gusarov // Autoclaved silicate materials and structures. Cementing materials: Collected tr. VNIIstrom. - M., 1981. -Vol. 44 (72). S.46-53).

Comparative analysis with the prototype allows us to conclude that the inventive raw material mixture differs from the well-known introduction of diamond mining waste as magnesium-containing mining waste and, as a result, new quantitative data, providing a more complete use of the raw materials to obtain silicate products. The content of binder components in quantities, wt.%: Quicklime less than 11.77, sand less than 11.11 and diamond mining waste less than 37.5, does not provide sufficient physical and mechanical characteristics, and the content of binder components in quantities, wt.%: quicklime more than 33.33, sand more than 41.67 and diamond mining waste more than 73.17, worsens the characteristics of the final material, therefore it is not economically feasible. The raw material mixture also has a new quantitative ratio, in which the content of binder and aggregate sand, respectively, less than 26 wt.% And more than 74 wt.%, As well as more than 55 wt.% And 45 wt.% Does not lead to a noticeable improvement in the characteristics of the final material or makes them worse. Thus, the claimed technical solution meets the criterion of "novelty."

Analysis of the known raw material mixtures (AS USSR No. 912707, С04В 15/06, 03/15/1982) used in the production of silicate products showed that the use of magnesium-containing waste from the mining industry (a processing product of asbestos-containing rocks) increases the strength of the raw material to 0, 93 MPa, compressive strength of silicate products up to 42 MPa, frost resistance up to 50 cycles, reduces water absorption up to 12.6%. The real increase in the raw strength was up to 2.82 MPa, the compressive strength of silicate products to 43.04 MPa, frost resistance up to 50 cycles, a decrease in water absorption to 8.43% indicates an unexpected increase in the physicomechanical characteristics of silicate products associated with mineralogical features the composition of diamond mining waste in combination with other components of the raw mix and the quantitative content of these components. This confirms that the claimed solution meets the criterion of "inventive step".

Example 1

The binder is preliminarily prepared by co-grinding quicklime (with an active CaO content of 80%) with sand dried to a moisture content of 1-1.5% and waste from the diamond mining industry to a specific surface of 4500-5000 cm ² / g in a ratio of 23.08%, respectively: 19.23%: 57.69%.

Then, aggregate sand with a particle size modulus of 1.54 and a moisture content of 1-1.5% in a ratio of 26%: 74%, respectively, is added to the binder and the mass is mixed until completely uniform. The resulting mass is moistened to a moisture content of 10% and mixed thoroughly. Next, the mixture is kept in a sealed chamber until the mixture is completely extinguished within 2-3 hours.

After quenching, the mixture is re-mixed with some grinding of the particles against each other, as a result of which the lumps of the silicate mixture and the colloidal crystallization structure of the set lime are destroyed. In this case, a certain amount of water is released from the intergranular space of the mixture, increasing its mobility and uniformity.

Then proceed to the process of molding raw material at a pressure of 20 MPa. After pressing, the raw material is kept before autoclaving. The aging time depends on the rate of quenching of the lime used, the content of active calcium oxide in the mass and varies between 0.5-1.0 hours. At this time, lime, exhibiting thixotropic properties, after the destruction of the initial colloidal crystallization structure under the influence of repeated mixing of the mixture again exhibits astringent properties and sets, due to which there is an increase in the strength of raw brick. The increase in strength due to hydration hardening of lime allows you to increase the rate of rise of steam pressure in the autoclave without fear of the formation of internal stresses in the raw material, exceeding its tensile strength. Next, autoclave processing is carried out according to the regime: pressure rise - 1.5 hours, isothermal exposure - 6 hours (at a pressure of 1.0 MPa), pressure release - 1.5 hours.

Example 2

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 18.18 (active CaO - 80%);

quartz sand in the binder - 27.27;

diamond industry waste - 54.55.

A raw mixture with a moisture content of 12% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively 55% and 45%. The raw brick is molded, as in example 1. The hydrothermal processing of raw in an autoclave is carried out according to the regime: pressure rise - 1.4 hours, isothermal exposure - 4 hours (at a pressure of 0.8 MPa), pressure drop - 1.4 hours.

Example 3

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 11.77 (active CaO - 80%);

quartz sand in the binder - 29.41;

diamond industry waste - 58.82.

A raw mixture with a moisture content of 12% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively 51% and 49%. Raw brick is molded, as in example 1. Hydrothermal processing of raw in an autoclave is carried out according to the regime: pressure rise - 1.5 hours, isothermal exposure - 6 hours (at a pressure of 1.0 MPa), pressure release - 1.5 hours.

Example 4

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 33.33 (active CaO - 80%);

quartz sand in the binder - 16.67;

diamond industry waste - 50.

A raw mixture with a moisture content of 10% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively, 30% and 70%. Raw brick is molded, as in example 1. Hydrothermal raw processing in an autoclave is carried out according to the regime: pressure rise - 1.2 hours, isothermal exposure - 4 hours (at a pressure of 0.6 MPa), pressure release - 1.2 hours.

Example 5

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 22.22 (active CaO - 80%);

quartz sand in the binder - 11.11;

diamond industry waste - 66.67.

A raw mixture with a moisture content of 12% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively 45% and 55%. The raw brick is molded, as in example 1. The hydrothermal processing of raw in an autoclave is carried out according to the regime: pressure rise - 1 hour, isothermal exposure - 6 hours (at a pressure of 0.4 MPa), pressure drop - 1 hour.

Example 6

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 16.66 (active CaO - 80%);

quartz sand in the binder - 41.67;

diamond industry waste - 41.67.

A raw mixture with a moisture content of 10% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively 36% and 64%. The raw brick is molded, as in example 1. The hydrothermal processing of raw in an autoclave is carried out according to the following regime: pressure increase - 1.35 hours, isothermal exposure - 6 hours (at a pressure of 0.8 MPa), pressure release - 1.35 hours.

Example 7

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 25 (active CaO - 80%);

quartz sand in the binder - 37.5;

diamond industry waste - 37.5.

A raw mixture with a moisture content of 10% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively, 40% and 60%. The raw brick is molded, as in example 1. The hydrothermal processing of raw in an autoclave is carried out according to the following regime: pressure increase - 1.35 hours, isothermal exposure - 6 hours (at a pressure of 0.8 MPa), pressure release - 1.35 hours.

Example 8

A binder is prepared, as in example 1, in the following ratio of components, wt.%:

quicklime - 14.63 (active CaO - 80%);

quartz sand in the binder - 12.2;

diamond mining waste - 73.17.

A raw mixture with a moisture content of 10% is prepared, as in example 1, with a ratio of binder and quartz sand-aggregate, respectively 41% and 59%. The raw brick is molded, as in example 1. The hydrothermal processing of raw in an autoclave is carried out according to the following regime: pressure increase - 1.35 hours, isothermal exposure - 4 hours (at a pressure of 0.8 MPa), pressure release - 1.35 hours.

The results of physical and mechanical tests are presented in table.2.

table 2
Physico-mechanical characteristics of silicate products Indicator Example Prototype one 2 3 four 5 6 7 8 The limit of compressive strength, MPa 21.43 40.89 23.69 25.14 29.47 24.3 43.04 33.77 28.0-42.0 The average density, kg / m ³ 1894 1917 1907 1915 1921 1907 1925 1911 - Water absorption,% 8.51 9.74 9.58 8.43 9.76 9.1 8.76 9.79 12.6-13.4 Softening coefficient 0.7 0.74 0.69 0.76 0.72 0.7 0.74 0.72 - Frost resistance, in cycles, not less 35 fifty 35 fifty fifty 35 fifty 35 45-50 The compressive strength of raw, MPa 1.83 2.82 2.61 1.95 2.76 1.91 2.07 1.89 0.41-0.93

From table 2 it is seen that with the introduction of diamond mining waste into the binder as magnesium-containing mining waste, the raw strength increases by 1.96-6.87 times, the strength of the products is comparable with the strength of the prototype products, frost resistance does not change, water absorption decreases 1.28-1.58 times. The inventive compositions of the raw material mixture have a high reactivity, which allows to obtain products with reduced autoclave processing (isothermal exposure (2-6 hours) and reduced pressure (from 1.0 to 0.4 MPa)), which in turn will reduce energy costs for autoclaving, thereby reducing energy intensity and increasing the productivity of the production process. Using the proposed compositions of raw mixtures will solve the problem of waste disposal of a diamond deposit in the Arkhangelsk diamondiferous province, the bulk of the overburden is up to 200 thousand tons per year, and at the same time get various silicate construction products necessary for the construction of GOKa processing lines and the construction of housing in the region.

Claims (1)

The raw material mixture for producing silicate products, consisting of a binder, including quicklime, sand and magnesium-containing mining waste, and aggregate sand, characterized in that it contains diamond-containing mining waste as magnesium-containing waste in the following ratio of components raw mix, wt.%: specified binder 26-55 sand aggregate 45-74, while the binder contains the following number of components, wt.%: quicklime 11.77-33.33 sand 11.11-41.67 specified waste 37.5-73.17