RU2313407C1 - Method for cleaning faces and internal rooms of buildings and other structures made of construction materials from various contaminations and blooms - Google Patents

Abstract

FIELD: treatment of surfaces, in particular, cleaning of faces, building entry vestibules and stair enclosures, other internal rooms and engineering constructions and architectural parts of buildings under construction, reconstruction and repair from various kinds of contaminations and blooms.

SUBSTANCE: method involves cleaning surface using high-speed flow (300-600 m/s), said surface being preliminarily cleaned using air-water stream having content of water component 0.001-0.01 of volumetric part into which potassium ferricyanide is introduced in an amount of 0.5-10 wt% and polyvinyl alcohol in an amount of 0.1-0.2 wt%; performing cleaning and simultaneously preserving surface against blooms using high-speed stream of water suspension containing finely dispersed (up to 100 micron) particles of clayish raw materials with concentration of clayish phase in suspension making 20-45 wt% and calcium bicarbonate used in an amount of 1-3 wt%; drying treated surface using high-speed air flow having temperature of 15-50 C.

EFFECT: increased efficiency in cleaning of building surfaces and prolonged repair-free time, as well as provision for mechanization and automation of cleaning process.

Description

The invention relates to surface treatment and can be used, in particular, when washing and cleaning facades, entrance halls and stairwells, other interior buildings and engineering structures and architectural details of buildings under construction, reconstructed and repaired from various types of pollution and efflorescence.

There is a method of cleaning the facades of buildings and structures from pollution, including efflorescence, which involves washing surfaces with large amounts of water with detergent mixed in the stream at a solution concentration of 0.2 ... 3% supplied to the treatment zone using Kranzle high-pressure apparatuses , "Karcher" et al. [1]. The disadvantages of this method are the high water consumption and its low efficiency, since after a short time remaining in the cleaned surface of the salt again appear on the surface. In addition, due to the high flow rate of water, this method is not applicable for washing and cleaning the interior.

Closest to the proposed is a method of cleaning buildings and structures from pollution and efflorescence, which includes the following operations:

- cleaning large buildups of salts, cement slurry residues and other contaminants mechanically using metal brushes;

- copious impregnation of the surface to be cleaned with water;

- manually using brushes or a high-pressure apparatus (up to 20 MPa) applying special (acidic) detergents to the wet surface (for example, facade cleaner No. 5 or Extra), 3-5 minutes exposure;

- wiping with a coarse cloth while washing products of neutralization with water. If necessary, the impregnation and subsequent cleaning is repeated several times until the removal of dirt and salts;

- hydrophobization with a roller or brush of the cleaned surface with special compounds (for example, "Disboxan-450" or "Water-repellent facade"). The treatment is repeated 2-3 times after drying of each applied layer [1].

The disadvantages of this method are low productivity, the use of mainly manual labor, the high consumption of special detergents, the possibility of re-manifestation of efflorescence over time. In addition, if there are additional contaminants on the surface to be treated, such as cement mortar or paint residues, they are removed using an additional operation. Detergent concentrates are not allowed to enter the surface of structures made of aluminum alloys and other non-ferrous materials, as well as marble and plastics.

The elimination of these disadvantages can be achieved by intensifying the process of cleaning surfaces from contaminants, including salt, with the simultaneous preservation and subsequent drying of the treated surface, in which the flow of moisture to the surface is stopped and thereby there are no conditions for the re-emergence of salts on the surface, and also decreases further surface contamination.

The intensification of washing, preservation and drying processes is carried out through the use of a high-speed (300 ... 600 m / s) air-based jet with the addition of liquid and solid components into it at different stages, initiating accelerated washing of contaminants, including efflorescences, and cleaning with preservation of the treated surface. The process is carried out in three stages: first, atmospheric and dirt-soiled contaminants and the “salted” surface are washed with a water-air stream with a water component of 0.001 ... 0.01 volume fraction, and iron-hydrogen potassium in the amount of 0.5 ... 10 wt is introduced into the water .% and polyvinyl alcohol in an amount of 0.1 ... 0.2 wt.%, then the surface is cleaned using a high-speed jet of an aqueous suspension containing fine (up to 100 μm) particles of clay raw materials with a concentration of 20 in the suspension ... 45 wt.% And acid carbon calcium acid - 1 ... 3 wt.%. At the same time, surface preservation occurs at the same time, as a result of which a separate hydrophobization operation is excluded and conditions for the penetration of moisture into the material are excluded. In the third stage, a high-speed air stream at a temperature of 15 ... 50 degrees Celsius is the intensive drying of the treated surface. Given that all three stages are performed by a high-speed air-based jet, there is the possibility of mechanizing the process and reducing the use of manual labor. There is also no need to use special detergents.

It should be noted that the exclusion of one of the proposed processing steps makes it not effective.

Introduction to the composition of water at the first stage of the process of iron-hydrogen potassium in the amount of 0.5 ... 10 wt.% And polyvinyl alcohol in the amount of 0.1 ... 0.2 wt.% Significantly accelerates the process of dissolution and washing of atmospheric and dirt dirt and efflorescence, disinfects the treated surface and prepares it for subsequent cleaning and preservation.

At the second stage, the high-speed jet of suspension intensively cleans the surface prepared at the first stage and, using finely dispersed clay raw materials with added calcium carbonate, simultaneously preserves it, creating a water-insoluble water-repellent film in the surface layer that is firmly connected to the base material.

At the third stage, the presence of a high-speed jet of air at a temperature of 15 ... 50 degrees Celsius provides accelerated drying of the surface.

This method was tested during the cleaning of red bricks with winter cement mortar on its ends, solidified cement mixture and efflorescences on the front surface. The specified brick was processed according to the usual process using metal brushes, water impregnation, double treatment with facade cleaner No. 5 and No. 4, wiping the treated surface with a rough cloth while washing off the neutralization products, after which the Water-repellent facade was waterproofed according to the instructions.

For comparison, similar red bricks were processed by the proposed method. A high-speed jet of water-air mixture was supplied from a compressor with a capacity of 3.5 cubic meters. meters per minute at a pressure of 2.8 atmospheres (flow velocity was 450 m / s) and a liquid component supply device, the composition of which included water in a volume of 0.006 volume fractions, with the addition of potassium iron-hydrogen sulfide in an amount of 7 wt.% and polyvinyl alcohol in the amount of 0.2 wt.%. Then, at the same process parameters, the surface was cleaned of various contaminants using instead of the liquid component an aqueous suspension containing finely dispersed (up to 100 μm) particles of clay raw materials at a concentration in suspension of 35 wt.% And acidic calcium carbonate - 2.5 wt.% . At the same time, on the surface to be treated, a film is firmly connected to the base, consisting of suspension products, which protects the surface from moisture penetration into it, that is, it preserves it. After that, the suspension was suspended in the treatment zone and the surface was treated with a high-speed stream of air at a temperature of 27 degrees Celsius until the surface completely dried.

After these types of processing, all external defects (cement mixture, traces of efflorescence) were removed, and in the usual way it took an average of 16 minutes to clean one brick, while the proposed method completely cleaned the brick within 2 minutes. Then all processed bricks were placed in a chamber in which a temperature of 30 degrees Celsius and a humidity of 95% were maintained. After 18 days, point traces of salts began to appear on bricks processed using conventional technology, and after 25 days noticeable efflorescence sites had already formed. Bricks processed by the proposed method did not show any efflorescence even 50 days after processing.

The exclusion of iron-hydrogen potassium and polyvinyl alcohol from the washing solution (at the first stage of purification) led to an increase in the washing time and, despite this, after a while, a repeated manifestation of efflorescence on the treated surface was observed.

In the absence of acidic calcium carbonate in the cleaning slurry (second stage of purification) 25 days after cleaning, point traces of salts appeared on the surface of the bricks.

Thus, the exclusion from the proposed method of individual operations or components sharply reduced the efficiency of the cleaning processes.

It should be noted that an increase in the content of these components over the above values practically did not change the cleaning speed and the time until the efflorescence again.

Information sources

1. Materials and production technologies for cleaning facades of buildings and engineering structures. Technical recommendations TR 118-01, Moscow, 2001.

Claims (1)

The method of cleaning the facades and interior of buildings and other structures from building materials from various contaminants and efflorescences, including cleaning the surface using a high-speed 300 ÷ 600 m / s jet, with the washing surface being cleaned first with a water-air stream containing a water component of 0.001 ÷ 0, 01 volume fraction with the introduction of water of iron-sulphide potassium in an amount of 0.5 ÷ 10 wt.% And polyvinyl alcohol in an amount of 0.1 ÷ 0.2 wt.%, Then clean with simultaneous conservation of the surface o efflorescence with a high-speed jet of an aqueous suspension containing finely dispersed particles of clay raw material up to 100 microns, with a clay phase concentration in the suspension of 20–45 wt.% and calcium carbonate in an amount of 1–3 wt.%, and then the treated surface is dried with a high-speed air jet at a jet temperature of 15-50 ° C.