RU2230715C2 - Raw meal for fabricating gypsum-vermiculite heat-insulation articles - Google Patents

Abstract

FIELD: manufacture of building materials.

SUBSTANCE: raw meal contains 70-80% gypsum and 20-30% expanded vermiculite obtained by reverse flotation technique from class (-0.64-0.00) mm waste from non-mica production formed during in conversion of ores. Articles have density 310-580 kg/m3 and heat conductivity 0.11-0.16 W/m.K. Articles are intended for heat insulation of building structures and equipment.

EFFECT: reduced density of articles.

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Description

The invention relates to the building materials industry, in particular to a raw material mixture for the manufacture of thermal insulation products used for thermal insulation of building structures, equipment.

A known composition for the manufacture of heat-insulating material, including, wt.%: Expanded vermiculite 5-15, refractory clay 55-75, hard bitumen 10-40. Products based on the known composition have a density of 700-900 kg / m ³ ; compressive strength 2.5-4.0 MPa; thermal conductivity 0.15-0.18 kcal / m · h · deg (A.S. No. 757505, MKI 3 C 04 V 43/00, BI No. 31, 1980).

A heat-insulating dry mixture is known, including 49-83 wt.% As Portland cement binder, and fractioned expanded vermiculite as a filler according to the partial residue on sieves 5.0 mm - 5%, 0.6 mm - 55%, less than 0.6 mm - 40% in an amount of 51-17 wt.%. Products from the known mixture have a density of 600-800 kg / m ³ ; thermal conductivity 0.12-0.16 W / m · k (RF Patent No. 2162067, IPC 7 C 04 V 28/04, BI No. 2, 2001).

The disadvantages of the known raw material mixtures include the fact that products based on them have a high density.

A known raw material mixture for the production of expanded clay, including clay 91-95% and vermiculite fraction (-0.63 + 0.00) mm of a certain chemical composition, obtained by reverse flotation of waste class (-0.63 + 0.00) mm mica formed during the redistribution of ores in an amount of 5-9 wt.%. Expanded clay is used to produce expanded clay with a bulk density of 363-465 kg / m ³ (RF Patent No. 2111186, IPC 6 C 04 B 14/12, C 04 B 38/08, BI No. 14, 1998). Although the known raw material mixture has a small bulk mass, it is intended to produce expanded clay gravel, which is used in the production of concrete as a light aggregate and, in addition, raw vermiculite is used as part of the mixture.

The closest to the claimed invention, a raw material mixture of the same purpose for the totality of features and which is adopted as a prototype, is a raw material mixture for the production of heat-insulating material, including gypsum (G) and vermiculite (B) with a ratio of components B: G equal to from 1: 1 to 1 : 3 or in wt.% From 50:50 to 25:75 (Dubenetsky K.N., Pozhin A.P. Vermiculite (properties, technology and application in construction), Leningrad. Publishing house of building literature, 1971, p. . 70, 71, 103), (prototype).

The disadvantage of this known raw material mixture is that heat-insulating products with an average density of less than 600 kg / m ³ can only be obtained with ratios B: G equal to from 1: 1 to 1: 2 or in wt.% From 50:50 to 33: 67, and when using vermiculite from an artificially composed mixture of two classes of fineness - small (-0.60 + 0.3) mm and medium (-5 + 0.60) mm for a ratio of 1: 1 (see table 1, example 9) and three classes of fineness - small (-0.60 + 0.30) mm, medium (-5 + 0.60) mm and large class (-10 + 5) mm (see table 1, example 10) according to GOST 12 865-67.

When creating the invention, the task was to obtain gypsum-vermiculite insulation products with an average density of less than 600 kg / m ³ suitable for thermal insulation of building structures and equipment.

Therefore, the technical result achieved by the invention is to reduce the density of finished heat-insulating products and reduce the consumption of vermiculite.

The specified technical result is achieved by the fact that the raw material mixture for the production of gypsum-vermiculite heat-insulating products, including gypsum and expanded vermiculite, according to the invention, contains vermiculite, class (-0.63 + 0.00) mm, obtained by reverse flotation from mica waste by redistribution of ores, in the following ratio of components, wt.%: gypsum 70-80, expanded vermiculite - 20-30.

The analysis of the prior art by the applicant, including a search by patent and scientific and technical sources of information, and the identification of sources containing information about analogues of the claimed invention, allowed to establish that the applicant did not find an analogue characterized by features identical to all the essential features of the claimed invention. The definition from the list of identified analogues of the prototype as the closest in the set of essential features of the analogue allows you to identify the set of essential in relation to the perceived technical result of the distinguishing features in the claimed substance set forth in the claims.

Therefore, the claimed invention meets the condition of "novelty."

In the claimed invention, the new is the ratio of the components included in the mixture and the particle sizes of the used vermiculite. To obtain products with a density of up to 600 kg / m ³ in the prototype, the ratio of components B: D is 1: (1-2), and vermiculite is an artificially composed mixture of grains from 0.3 to 10 mm in size. Using other ratios B: D and grain sizes of vermiculite leads to the production of products with a density of more than 600 kg / m ³ (table 1). The bulk mass of gypsum (1000 kg / m ³ ) is 6.6 times higher than the bulk mass of expanded vermiculite (150 kg / m ³ ), and since the claimed invention takes gypsum almost 4 times more than the prototype, the technical result obtained , namely, a decrease in the density of the obtained products from the claimed mixture, in comparison with the prototype does not follow explicitly from the known dependencies and patterns. In addition, a characteristic property of vermiculite is intensive expansion when rapidly heated, it is lost during grinding, therefore, it is unambiguous to say without experimental work that vermiculite is of class (-0.63 + 0.00) mm obtained from waste of class (-0.63+ 0.00) mm of non-mica production formed during the redistribution of ores by reverse flotation will not be able to swell (see Onatsky SP Production of expanded clay. - M .: Stroyizdat, 1987, p. 36).

Therefore, the claimed invention meets the condition of "inventive step".

Information confirming the possibility of carrying out the invention with obtaining the above technical result.

Substances used in the mixture:

gypsum grade G-4 according to GOST 125-79;

crude vermiculite is obtained by the reverse flotation method of wastes of the class -0.63 + 0.00 mm of non-mica production formed during ore redistribution, it has the following chemical composition, wt.%: SiO ₂ - 40.15; TiO ₂ 1.16; AlO ₃ - 11.01; Fe ₂ O ₃ - 14.05; FeO - 1.0; MnO - 0.10; CaO - 1.44; MgO - 17.49; Na ₂ O - 0.32; K ₂ O - 4.19; P ₂ O ₅ - 0.15; SO ₃ - 0.05; F 1.44; Ppp - 7.45.

Then, crude vermiculite obtained from waste from unmanned production is expanded at a temperature of 900 ° C for 7 minutes.

Example 1

A portion of gypsum in an amount of 80 g is mixed with 20 g of expanded vermiculite and thoroughly mixed in dry form at room temperature. Then the dry mixture is moistened by adding 1.2 parts of water to 1 part of the mixture, mixed until the components are mixed uniformly. Samples of a cylindrical shape measuring 50 × 50 mm (diameter and height) were formed from the resulting mixture and dried at room temperature. The composition of the mixture and data on determining the properties of the obtained products are shown in table 2, composition 1.

Example 2

The raw mix is prepared according to example 1, but with the difference that gypsum is taken in an amount of 75 g, expanded vermiculite 25 g, 1.38 parts of water are taken per 1 part of the mixture. The composition of the mixture and data on determining the properties of the obtained products are shown in table 2, composition 2.

Example 3

The raw mixture is prepared according to example 1, but with the difference that gypsum is taken 72 g and expanded vermiculite 28 g, and 1.48 parts of water are taken for 1 part of the mixture. The composition of the mixture and data on determining the properties of the obtained products are shown in table 2, composition 3.

Example 4

The raw mixture is prepared according to example 1, but with the difference that gypsum is taken in an amount of 70 g, expanded vermiculite 30 g, 1.55 parts of water are taken per 1 part of the mixture. The composition of the mixture and data on determining the properties of the obtained products are shown in table 2, composition 4.

From the data shown in table 2, it follows that the optimal ratio of ingredients in the mixture are compositions 1-4. The composition shows that a decrease in the content of expanded vermiculite of less than 20 wt.% Is impractical, since the density of the products increases to 660 kg / m ³ and thermal conductivity increases, and an increase in the content of expanded vermiculite in excess of 40 wt.% Leads to a sharp decrease in the strength of the product (compositions 6 , 7).

Thus, the proposed composition of the raw mix for the production of heat-insulating products provides products with a density of less than 600 kg / m, ³ sufficient compressive strength and thermal conductivity in accordance with GOST 16381-77.

The use of the claimed invention provides:

a decrease in the density of gypsum-vermiculite products by 1.12-1.15 times (by 12-15%);

a decrease in the thermal conductivity of gypsum-vermiculite products by 1.6-2.3 times in comparison with monogypsum products;

identification of a new type of mineral additive in the form of small-sized vermiculite of the class (-0.63 + 0.00) mm for the manufacture of gypsum-based thermal insulation products;

expanding the use of small vermiculite with a particle size of -0.63 + 0.00 mm, which is now being sent to dumps in domestic practice;

increased use of natural resources;

reduction of vermiculite consumption for heat-insulating products with a density of less than 600 kg / m ³ .

The above information indicates that when using the claimed invention, the following combination of conditions:

- a tool embodying the claimed substance in its implementation, is intended for use in industry, namely in the building materials industry for the manufacture of heat-insulating products used for thermal insulation of building structures and equipment;

- for the claimed substance in the form as described in the independent clause of the claims, the possibility of its implementation using the examples described in the application is confirmed;

- the claimed substance in its implementation is capable of ensuring the achievement of the technical result perceived by the applicant.

Therefore, the claimed invention meets the condition of “industrial applicability”.

Claims (1)

Raw mix for the production of gypsum-vermiculite heat-insulating products, including gypsum and expanded vermiculite, characterized in that it contains vermiculite class (-0.63 + 0.00) mm, obtained by reverse flotation from non-mica waste, by ore redistribution at the following ratio of components, wt.%: gypsum 70-80, expanded vermiculite 20-30.