RU2239687C2 - Method of preventing slipperiness of pavements, raw mix for preparation of anti-ice-crusted ground, pavement-slipperiness suppressing reagent and a method for preparation thereof - Google Patents

Abstract

FIELD: deicer means.

SUBSTANCE: slipperiness of pavement is prevented by putting calcium-magnesium acetate-based reagent thereon in the form of grainy material with particle size 0.1 to 12 mm. Reagent is obtained from raw mix containing, wt parts: dolomite with 0.2-16% silicon inclusions or dolomitized limestone with 0.2-5% silicon inclusions, 180-200; ice or concentrated acetic acid, 50-150; potassium carbonate aqueous solution or 25% aqueous ammonia solution, 0.5-2; poly(ethylene glycol) or poly(propylene glycol), or their derivatives with biodegradability not more than 30 days, or polyvinyl alcohol with biodegradability not more than 60 days, 0.1. Preparation procedure: dolomite or dolomitized limestone is mixed with water and acetic acid, resulting mixture is treated in thin layer with potassium carbonate aqueous solution at potassium carbonate-to-water ratio between 1:1 and 0.5:3 or with 25% aqueous ammonia solution, or with mixture of potassium carbonate aqueous solution or 25% aqueous ammonia solution with poly(ethylene glycol) or poly(propylene glycol), or their derivatives as above.

EFFECT: improved environmental condition, essentially avoided residual acetic acid in reagent, and increased deicer quality.

8 cl, 1 dwg

Description

The invention relates to road maintenance production, in particular to methods of dealing with icy conditions on roads, bridges, overpasses, as well as airfields.

There is a method of preventing slippage of road surfaces by applying sodium chloride to the surface of coatings (see GV Bialobrzessky et al. Fighting winter slippery on roads. - M.: Transport, 1975, p.26).

The disadvantage of this method is the acceleration of the destruction of road surfaces and reinforced concrete structures, high corrosion of metal parts of cars, salinization of roadside soil.

Closest to the proposed method is a method of preventing slippage of road surfaces by coating a chemical with a deicing agent — a by-product of the production of polytetramethylene ether glycol based on sodium acetate. This substance is used both in solid form in a mixture with sand, and in liquid form - using watering machines. The consumption of the solid mixture is 300 kg per 1000 m ² . The liquid form is used in an amount of 0.2-0.3 l / m ² (see RU 2178035 C1, IPC E 01 C 11/24, publ. 10.01.2002).

The known method is not safe enough due to the presence of sodium chloride in the reagent, and also not technologically advanced due to the need to mix it with sand when used in solid form.

A known raw material mixture for producing a deicing agent, including hydrated dolomitic lime, glacial acetic acid, water and potassium acetate. A method of obtaining a reagent is to pre-mix dolomitized lime, glacial acetic acid and water, followed by the introduction of potassium acetate into the resulting mixture (see US Pat. No. 5,219,483, publ. 06/15/1993).

Closest to the invention is a raw material mixture to obtain anti-icing reagent to prevent slipping of road surfaces, including dolomite or dolomitic limestone, acetic acid and water. The content in dolomite Mg CO ₃ up to 50%. The content of a suspension of dolomite in water and acetic acid in the mixture is 70 mol.% CaCO ₃ and 30 mol.% Acetic acid (see US patent 5219483, publ. 06/21/1993). A method for producing an anti-icing reagent, including mixing dolomite or dolomitic limestone with water and then with acetic acid, is also described there. Unreacted acetic acid is washed with water. This method is the closest analogue to the method according to the invention.

A disadvantage of the known reagent and its production method is the presence of free acetic acid, which reduces environmental and corrosion safety.

The objective of the invention is to increase the environmental safety of the method and reagent, reducing the content of free acetic acid, as well as improving the manufacturability of the use of the reagent.

The problem is solved in that in the method of preventing slippage of road surfaces by applying an anti-icing reagent based on an acetic acid salt as an anti-icing reagent, a reagent based on a calcium-magnesium salt of acetic acid obtained from a raw mix containing max.

Dolomite with content

silicon inclusions

0.2-16 wt.% Or dolomi-

titled limestone

with silicon

inclusions 0.2-5 wt.% 180-200

Acetic acid 50-150

Aqueous carbonate solution

potassium or 25%

ammonia water 0.5-2

Polyethylene glycol or

polypropylene glycol or

their derivatives

biodegradable

no more than 30 days or

polyvinyl alcohol

biodegradable

no more than 60 days 0-1

In this case, acetic acid is used glacial or concentrated. Also, the deicing reagent is applied in the form of bulk material with a particle size of 0.1-12 mm. In addition, the anti-icing reagent is applied in liquid form. The task is also solved by the fact that the raw material mixture to obtain anti-icing reagent to prevent slipping of road surfaces, including dolomite or dolomitic limestone, acetic acid and water, contains dolomite with a content of silicon inclusions of 0.2-16 wt.%, Dolomitic limestone with a silicon content inclusions 0.2-5 wt.% and additionally contains an aqueous solution of potassium carbonate with the ratio of potassium carbonate: water 1: 1-0.5: 3 or 25% ammonia water, as well as polyethylene glycol or polypropylene ol or a derivative thereof with a biodegradability of not more than 30 days, or polyvinyl alcohol having a biodegradability of not more than 60 days at the following component ratio, mass parts .:

Dolomite with content

silicon inclusions

0.2-16 wt.% Or dolomi-

titled limestone

with silicon

inclusions 0.2-5 wt.% 180-200

Acetic acid 50-150

Aqueous carbonate solution

potassium or

25% ammonia water 0.5-2

Polyethylene glycol or

polypropylene glycol or their

derivatives

biodegradable

no more than 30 days or

polyvinyl alcohol

biodegradable

no more than 60 days 0-1

In this case, acetic acid is used glacial or concentrated.

In addition, the task is solved by the fact that in the method of producing anti-icing reagent to prevent slippage of road surfaces, including the preparation of a mixture of dolomite or dolomitic limestone with water and acetic acid, dolomite with a content of silicon inclusions of 0.2-16 wt. % or dolomitic limestone with a content of silicon inclusions of 0.2-5 wt.%, the prepared mixture in a thin layer is treated with an aqueous solution of potassium carbonate at a ratio of potassium carbonate: in yes 1: 1-0.5: 3 or 25% ammonia water, or a mixture of an aqueous solution of potassium carbonate or 25% ammonia water with polyethylene glycol or polypropylene glycol or their derivatives with biodegradability of not more than 30 days or polyvinyl alcohol with biodegradability not more than 60 days, while the components are taken in the following ratio, parts by weight:

Dolomite with content

silicon inclusions

0.2-16 wt.% Or

dolomitic limestone

with silicon

inclusions 0.2-5 wt.%

  180-200

Acetic acid 50-150

Aqueous carbonate solution

potassium or 25%

ammonia water 0.5-2

Polyethylene glycol or

polypropylene glycol

or their derivatives

biodegradable

no more than 30 days

or polyvinyl

biodegradable alcohol

no more than 60 days 0-1.

In this case, acetic acid is used glacial or concentrated.

The invention is as follows. Reagent is prepared first. For its preparation, the following components are used.

Dolomite composition, wt.%:

CaO 30-42, MgO 15-23, SiO ₂ 0.2-16, R ₂ O ₃ 0.003-0.7, Fe ₂ O ₃ 0.005-0.65, H ₂ O not more than 5, calcination loss (p .pp) - the rest. Dolmitized limestone composition, wt.%: CaO 34-35; MgO 14-18; SiO ₂ 0.2-5; R ₂ O ₃ 0.003-0.8; Fe ₂ O ₃ 0.005-0.64; H ₂ About not more than 8, p.p.p.- the rest.

Acetic acid that meets the following requirements for the content of components in wt.%:

acetic acid is not less than 99.5, acetic anhydride is not more than 0.004, sulfates are not more than 0.05, chlorides are not more than 0.0003,

heavy metals precipitated by hydrogen sulfide, not more than 0.0004, the residue after evaporation of 0.0004.

Potassium carbonate in the form of an aqueous solution with a ratio of potassium carbonate: water 1: 1-0.5: 3. Ammonia water of 25% concentration. The following compounds are used as derivatives of polyethylene glycol or polypropylene glycol with biodegradability of not more than 30 days: ethoxylated polyethylene glycol cocoate, polypropylene glycol containing sodium hyaluronate, carboxylated polypropylene glycol of rapeseed oil.

Polyvinyl alcohol with biodegradability of not more than 60 days, for example, brand A.

Example.

A method of obtaining a reagent is as follows. Ground dolomite with a content of siliceous inclusions of 8 wt.% Is mixed with water, concentrated acetic acid is introduced into the resulting suspension. Then the prepared mixture in a thin layer is treated on a conveyor belt with a mixture of an aqueous solution of potassium carbonate with polyvinyl alcohol and dried at a temperature of 80 ° C.

Processing the prepared mixture can also be carried out in a suspended layer.

The resulting reagent calcium-magnesium acetate is a loose non-caking material with 100% friability with a particle size of 0.1-12 mm, which allows it to be transported in bulk.

The presence of silicon inclusions in the initial dolomite and dolomitic limestone provides abrasive properties to the reagent, which also contributes to an increase in deicing properties and a decrease in the slippery of the road surface. In this case, there is no need to mix it with sand when using a dry reagent. Prepared the following mixtures of components are shown in table 1.

In examples 1, 2, 5, the ratio of potassium carbonate: water is 1: 1, in examples 3, 4, 6 the ratio of potassium carbonate: water is 0.5-3. When using other glycols, the results are similar.

The resulting reagents were tested for residual acetic acid. The test results are shown in table 2.

Tests for biodegradability, water toxicity, metal corrosion and the durability of asphalt concrete were also conducted. The durability of the asphalt concrete was tested in the cyclic freezing mode for 3-4 hours at -20 ° C and thawing in a 5% aqueous reagent solution. The results are shown in table 2.

The data obtained indicate a high quality reagent. The reagent decomposes at positive temperatures for 14 days and does not have a toxic effect on roadside vegetation, but on the contrary, when decomposed, it provides oxygen access to plant roots, acting as a soil cultivator.

The reagent does not pollute water bodies, as does not exceed MPC (maximum permissible concentration).

The reagent does not cause corrosion of steel and magnesium alloys, but noticeably inhibits its corrosion over time. The drawing shows the effect of reagents on corrosion of body steel. As can be seen from the above data, the corrosion of body steel for a 5% solution of the reagent according to the invention is at the level of corrosion in drinking water.

The described reagent was used to prevent slippage of the road surface.

A granular reagent, calcium-magnesium acetate with a particle size of 0.1-0.3 mm, was applied to the roadway with an ice formation using known mechanized means. The reagent consumption was 30 g / m ² .

You can also apply the reagent in liquid form - in an aqueous solution.

When applying the compositions according to examples 1-6, the temperature of the effective use of the reagent was determined. When using the reagent in example 2, it was -30 ° C, and in examples 1, 3-6 it increases to -45 ° C, which is due to the synergistic effect of glycols. It is also advisable to use the reagent to prevent slippage of airfield coatings, as along with the prevention of ice formation, corrosion of metals used in aircraft construction is prevented and significantly reduced.

Claims (8)

1. A method of preventing slippage of road surfaces by applying an icing reagent based on an acetic acid salt to the coating, characterized in that a calcium-magnesium salt of acetic acid obtained from a raw material mixture containing, by weight, is used as the specified anti-icing reagent dolomite with a content of silicon inclusions of 0.2-16 wt.% or dolomitic limestone with a content of silicon inclusions of 0.2-5 wt.% 180-200 Acetic acid 50-150 An aqueous solution of potassium carbonate or 25% ammonia water 0.5-2 Polyethylene glycol, or polypropylene glycol, or their derivatives with biodegradability not more than 30 days or polyvinyl alcohol with biodegradability not more than 60 days 0-1 2. The method according to claim 1, characterized in that the acetic acid is used glacial or concentrated. 3. The method according to claim 1, characterized in that the deicing agent is applied in the form of bulk material with a particle size of 0.1-12 mm 4. The method according to claim 1, characterized in that the deicing agent is applied in liquid form. 5. The raw material mixture to obtain anti-icing reagent to prevent slipping of road surfaces, including dolomite or dolomitic limestone, acetic acid and water, characterized in that dolomite with a silicon content of 0.2-16 wt.% Or dolomitic limestone with a content of silicon inclusions is used 0.2-5 wt.% And additionally contains an aqueous solution of potassium carbonate with a ratio of potassium carbonate: water 1: 1-0.5: 3 or 25% ammonia water, as well as polyethylene glycol or polypropylene glycol, or their production aqueous with biodegradability of not more than 30 days or polyvinyl alcohol with biodegradability of not more than 60 days in the following ratio of components, wt.h .: Dolomite with a content of silicon inclusions 0.2-16 wt.% Or dolomitic limestone with a content of silicon inclusions 0.2-5 wt.% 180-200 Acetic acid 50-150 An aqueous solution of potassium carbonate or 25% ammonia water 0.5-2 Polyethylene glycol, or polypropylene glycol, or their derivatives with biodegradability not more than 30 days or polyvinyl alcohol with biodegradability not more than 60 days 0-1 6. The raw material mixture according to claim 6, characterized in that the acetic acid is used glacial or concentrated. 7. A method of producing an anti-icing reagent to prevent slippage of road surfaces, including the preparation of a mixture of dolomite or dolomitic limestone with water and acetic acid, characterized in that dolomite with a content of silicon inclusions of 0.2-16 wt.%, Dolomitic limestone is used to prepare the mixture with a content of silicon inclusions of 0.2-5 wt.%, the prepared mixture in a thin layer is treated with an aqueous solution of potassium carbonate with a ratio of potassium carbonate: water 1: 1-0.5: 3, or 25% ammonia water or with a mixture of an aqueous solution of potassium carbonate or 25% ammonia water with polyethylene glycol, or polypropylene glycol, or their derivatives with biodegradability of not more than 30 days or polyvinyl alcohol with biodegradability of no more than 60 days, while the components are taken in the following ratio, wt. hours: Dolomite with a content of silicon inclusions 0.2-16 wt.% Or dolomitic limestone with a content of silicon inclusions 0.2-5 wt.% 180-200 Acetic acid 50-150 An aqueous solution of potassium carbonate or 25% ammonia water 0.5-2 Polyethylene glycol, or polypropylene glycol, or their derivatives with biodegradability not more than 30 days, or polyvinyl alcohol with biodegradability not more than 60 days 0-1 8. The method according to claim 7, characterized in that the acetic acid is used glacial or concentrated.