RU2255075C2 - Method of processing porous building materials - Google Patents

Abstract

FIELD: manufacture of building materials.

SUBSTANCE: subject of invention is processing of building materials used under unfriendly operation conditions as well as for design refinement of buildings or constructions in any color spectrum. For this end, building materials are impregnated by impregnating compositions. Process comprises placing objects of these materials in impregnating chamber, evacuation, conditioning, impregnation, and discharge of objects. Impregnation is performed from one to ten times by feeding mixture of dies with hydrophobic soak into chamber under pressure 6 to 30 atm for 30 sec to 10 min, while gradually reducing pressure in impregnating chamber to atmospheric value. Dies utilized are of latex or acrylic type and possess diffusion properties, whereas hydrophobic soak is a silicone-based soak possessing membrane properties. Object to be processes can be bricks, parts based of cement, gypsum cement, natural stone, wood, and ceramics.

EFFECT: reduced operation cost, improved quality of products, and achieved design refinement of buildings or constructions.

9 cl

Description

The invention relates to the field of the construction industry, in particular to methods for processing building materials used under adverse operating conditions, as well as for the design study of buildings and structures in any color scheme.

The well-known “Method of impregnation of porous material” (ed. Certificate of the USSR No. 1463731; class C 04 B 41/62; 1985).

According to this invention, the impregnated material is placed in a chamber, the lower part of which is filled with an impregnating liquid. The chamber is pre-evacuated to 0.3 atm, after which the steamed and dried material is immersed in an impregnating liquid bitumen heated to a temperature of 160 ° C and kept under vacuum for 1 hour. After that, the pressure is immediately equalized to atmospheric. Alternating exposure to pressure and vacuum is carried out until the desired impregnation depth (1.45 mm) is reached.

The closest to the claimed technical essence and the achieved result is the invention “A method for processing porous building products” (ed. Certificate of the USSR No. 1357402; class C 04 B 41/53; 1984).

According to this invention, porous cellular concrete building products after autoclaving are loaded into the impregnation chamber and vacuum up to 95-99.5% vacuum for 10-25 minutes, the organosilicon compound is impregnated with an aqueous emulsion, and then the products are further evacuated to the previous vacuum level with an exposure equal to half the time of preliminary evacuation. As a result of processing, the average depth of impregnation is 15 mm with a deviation from the average of ± 1.5-2 mm.

This technical solution is taken as a prototype.

The disadvantages of the prototype are:

- significant costs for the process, which before processing requires preliminary exposure of the products in an autoclave, drying and heating to 60 ° C; repeated evacuation with exposure; additional costs for staining products, which are absent in this technological process;

- a small depth of impregnation due to the rapid release of vacuum and the occurrence of hydraulic shock, which in turn leads to a violation of the capillary structure of the material and impedes the penetration of the impregnating composition into the thickness of the processed material, impairing the mechanical strength of the products and their quality.

The tasks solved by the invention are:

- cheaper technological process for the production of building materials, painted and impregnated with protective substances;

- achieving high quality products, improving their operational properties;

- providing design opportunities for buildings and structures made of building material made using the claimed method.

The tasks are solved by the fact that in the known method of processing porous building materials with impregnating compositions, including placement of products in an impregnation chamber, evacuation, aging, impregnation and unloading of products, impregnation is carried out from one to ten times by feeding a mixture of dyes with hydrophobic impregnation under pressure of 6-30 atm for 0.5-10 minutes with a gradual decrease in vacuum in the impregnation chamber to atmospheric pressure.

The tasks are also solved by the fact that, as dyes, for example, dyes having diffusion properties on a latex or acrylic basis are used, and as hydrophobic impregnations, for example, silicone-based impregnations having membrane properties are used.

These tasks are also solved by the fact that as a porous building material use brick, cement-based products, gypsum, ceramic products, products based on natural stone, wood-based products.

New significant features in the method of processing porous building materials are:

- the implementation of the impregnation by feeding into the impregnation chamber a mixture of dyes with hydrophobic impregnation under a pressure of 6-30 atm for 0.5-10 minutes with a gradual decrease in the vacuum in the impregnation chamber to atmospheric pressure; the specified impregnation is carried out from one to ten times.

Private new features of the claimed method are:

- the use of dyes with diffusion properties, made on a latex or acrylic basis, as coloring matter;

- the use of hydrophobic impregnation with membrane properties made on the basis of silicone;

- the use of brick, products based on cement, gypsum, ceramic products, products based on natural stone, and products based on wood as products from porous building material.

The supply of a mixture of dyes with hydrophobic impregnation into the impregnation chamber allows combining the operations of the technological process for painting and impregnating building materials, which entails the simplification and cheapening of production.

The flow of 6-30 atm to the mixture in the impregnation chamber of the mixture ensures its atomization to a state close to gaseous, and, as a result, deep penetration into the pores of the processed material.

A decrease in the supply pressure of the mixture of less than 6 atm entails a decrease in the speed of movement of the sprayed particles and the depth of their penetration into the pores of the material, and consequently, a decrease in the thickness of the treated layer, which affects the operational stability of the products.

An increase in the supply pressure of the mixture of more than 30 atm is economically and technologically impractical, because pressure up to 30 atm is necessary and sufficient for impregnation and dyeing of products.

The flow of the mixture into the impregnation chamber for 0.5-10 minutes ensures a smooth decrease in the vacuum in the chamber, eliminates water hammer, which allows you to maintain the integrity of the structure of the building material during processing, and also allows you to get a painted and hydrophobic layer of the required thickness on the building material.

Reducing the time of feeding the mixture into the chamber in less than 0.5 min entails a decrease in the thickness of the treated layer, and also provokes the occurrence of water hammer, which reduces the penetration depth of the mixture into the thickness of the material, worsening its structure due to violation of the integrity of the capillaries, and, as a consequence, worsening mechanical strength of products and their quality.

The impregnation from one to ten times is due to the capillary and porous structures of the processed material. According to the number of pores in the solid and their sizes, solids are usually divided into subcapillary (less than 0.2 microns), capillary (0.2-100 microns) and supercapillary (more than 100 microns). Most building materials are porous structures with different structures, the amount of impregnation required is inversely proportional to their structure.

For one impregnation process materials having a supercapillary structure, for example, brick, lightweight concrete, wood-based products.

For two to five impregnations, materials with a capillary structure are processed, for example, cement-based products (cement-bonded particleboard, cement-fiber board, asbestos-cement plate, etc.); from 5 to 10 impregnations must be carried out when processing subcapillary building materials, for example, some types of ceramics and natural stone.

The use of substances with diffusion properties as dyes in the presence of supply pressure and vacuum allows to increase the speed of movement of the particles of the mixture and the depth of their penetration into the thickness of the building material.

The use of dyes based on latex or acrylic allows you to get a surface with high water resistance, resistance to abrasion, ultraviolet radiation and salting out surfaces. These dyes have a high hiding power, good occupancy, do not turn yellow over time.

The use of hydrophobic impregnation, which has membrane properties, allows you to protect buildings and structures from moisture and frost. The silicone base impregnation allows you to adjust the steam-water diffusion, i.e. the surface becomes able to "breathe", releasing excess moisture and not missing unnecessary.

The use of brick, cement-based products, ceramics, natural stone, gypsum and wood-based products as a building material makes it possible to obtain building materials with high hydrophobicity, as a result of which their resistance to adverse weather conditions increases, moisture and frost resistance increase; in addition, the impregnation of these materials with a mixture, including dyes, allows you to perform various design studies of buildings and structures.

The use of wood-based products as a building material allows, in addition, to reduce the linear expansion of products when exposed to moisture.

The method was carried out as follows.

M150 silicate brick was placed on a rack providing access to all brick surfaces, and without preliminary drying and heating it was placed in an autoclave-type impregnation chamber. The traditional vacuum pump was turned on and a vacuum in the chamber of 99.9% was created and maintained in this mode for 10 minutes. During this period, the air in the pores of the brick is completely pumped out. Then, through a nozzle installed in the chamber, a mixture of acrylic-based dye and hydrophobic liquid was supplied under a pressure of 12 atm. The mixture was fed continuously until the vacuum was completely balanced.

The dye Fassaden Fullfarbe brand to obtain the mixture was pre-mixed with a hydrophobic liquid brand WBS Mikrosil in a ratio of 1: 1. The amount of dye and hydrophobic liquid is changed depending on the need to obtain operational characteristics (color, hydrophobicity) of the building material.

The flow of the mixture through the nozzles at a pressure of 12 atm ensures its atomization to a state as close to gaseous as possible. At the same time, when the mixture is supplied in the chamber, the vacuum begins to decrease, and the mixture gradually penetrates into the pores of the brick. In this case, the decrease in vacuum in the chamber is inversely proportional to the volume of the supplied mixture.

The mixture was filed for 2 minutes. During this time, the vacuum decreased to zero, i.e. compared with atmospheric pressure.

With a smooth decrease in rarefaction, the mixture filled all the pores, the structure of the brick did not break due to the lack of hydraulic shocks that occur when using liquid impregnating substances and an instant decrease in vacuum. Impregnation of silicate brick was carried out at a time, because its structure is supercapillary.

To achieve the necessary operational characteristics of building materials having capillary structures, impregnations are carried out 2-3 times, and with subcapillary structures, it is required to carry out from 3 to 10 impregnations.

As an example of the processing of building material from cement-based products, we took a cement-bonded slab of the TsSP-1 brand (1250 × 2600 × 10 mm), manufactured industrially. Carried out the technological operations described above. The feed pressure of the mixture was 12 atm, and the feed time was 1.5 minutes.

The mixture was prepared for intensive staining in a ratio of 1: 1. Fassaden Fullfarbe paint was used as a dye, and WBS Mikrosil hydrophobic liquid was used. The plate was impregnated twice.

A ceramic brick of grade 100 was used as a ceramic product. The supply pressure of the mixture was set to 8 atm, the feed time was 0.5 min. The mixture was prepared in the same way as for the processing of cement-based products. The ceramic brick was impregnated at a time.

Unpolished marble tiles 300 × 300 × 10 mm were used as natural stone. Used transparent dyes used to obtain colored glass; the mixture was fed into the chamber under a pressure of 16 atm for 5 min. The impregnation was carried out 5 times. The penetration depth is through. The structure of marble has not changed and has become hydrophobic. In the absence of a sugar effect and the preservation of the natural pattern of the stone, it seems possible to give the latter any color shade.

Transparent dyes were also used to process Karelian granite in the form of 300 × 300 × 10 mm tiles of the Diabaz brand. The mixture was fed under a pressure of 30 atm for 10 minutes. The impregnation was carried out ten times.

Processing of building material from natural stone made it possible to preserve its color and natural inclusions, significantly increasing resistance to moisture.

The processing of porous gypsum-based building material was carried out using a gypsum fiber board of the GVL brand (1200 × 2500 × 13 mm), in the structure of which there are wood-based fibers (cellulose). The feed pressure of the mixture was 8 atm, the feed time was 1 min. Impregnation was carried out at a time. Depth of processing - through.

Tests of the claimed method of processing porous building material were carried out in the laboratory of LLC “Extrom” in Vladimir.

Claims (9)

1. A method of treating porous building materials with impregnating compositions, comprising placing in the impregnation chamber products from these materials, evacuating, holding, impregnating and unloading these products, characterized in that the impregnation is carried out from one to ten times by feeding a mixture of dyes with hydrophobic into the impregnation chamber by impregnation under a pressure of 6-30 atm for 30 s-10 min with a gradual decrease in the vacuum in the impregnation chamber to atmospheric pressure. 2. The method according to claim 1, characterized in that the dyes use dyes with diffusion properties, on a latex or acrylic basis. 3. The method according to claim 1 or 2, characterized in that as a hydrophobic impregnation, an impregnation having membrane properties based on silicone is used. 4. The method according to one of claims 1 to 3, characterized in that a brick is used as said product. 5. The method according to one of claims 1 to 3, characterized in that as the specified products use products based on cement. 6. The method according to one of claims 1 to 3, characterized in that as these products use products based on gypsum. 7. The method according to one of claims 1 to 3, characterized in that ceramic products are used as said products. 8. The method according to one of claims 1 to 3, characterized in that as these products use products based on natural stone. 9. The method according to one of claims 1 to 3, characterized in that as these products use wood-based products.