RU2353581C1 - Method of colouring ammonium nitrate for technological purposes - Google Patents

Abstract

FIELD: blasting operations.

SUBSTANCE: invention relates to the method of colouring ammonium nitrate for technological purposes, used for making explosive materials, particularly, for the production of high-density and porous ammonium nitrate with a characteristic distinctive colouring of the granules. It can be used in the manufacture of ammonium nitrate, for making emulsion and basic explosives. Method of colouring ammonium nitrate for technological purposes lies in the fact, that granulation of molten ammonium nitrate is granulated in the presence of organic dyes, taken in the quantity 10-100 mg to 1 kg of the finished product. Dye is put into the molten ammonium nitrate directly before granulating into the composition of pore-forming agent or surfactant or in the form of an aqueous solution or suspension. Dyes which do not lose colour in molten ammonium nitrate at a temperature of 190°C are used as colouring agents.

EFFECT: obtaining ammonium nitrate granules with homogenous uniform distinctive colouring.

2 cl

Description

The invention relates to chemical technology for producing inorganic substances used for the preparation of explosive materials, in particular to the production of ammonium nitrate for technical purposes with a characteristic distinctive color of granules, can be used in the production of ammonium nitrate used for the preparation of simple explosives and emulsion explosives.

For the preparation of emulsion and simple explosives, various brands of ammonium nitrate are used for technical purposes: granular high-density ammonium nitrate, porous ammonium nitrate with various values of oil absorption and bulk density.

A number of consumers in the manufacture of explosives simultaneously use various brands of ammonium nitrate. However, in the appearance of the granules, the brand of ammonium nitrate cannot be determined, therefore, granular products can be used for other purposes.

Analogues of the invention are not known to the authors.

The technical result consists in obtaining ammonium nitrate for technical purposes with a uniform uniform distinctive color of the granules.

To achieve the named technical result in the proposed method for dyeing ammonium nitrate for technical purposes, granulation of the ammonium nitrate melt is carried out in the presence of organic coloring substances introduced into the melt immediately before granulation in the composition of a pore-forming or surfactant additive or in the form of an aqueous solution or suspension in an amount of 10 100 mg per 1 kg of the finished product.

Ammonium nitrate is obtained in any known manner.

Organic coloring substances in the proposed method are pre-dissolved or dispersed in a solution or suspension of a pore-forming additive, or in a solution of a surface-active additive, or in water and introduced into the melt in the form of solutions or suspensions, which provides uniform uniform coloring of ammonium nitrate. When organic colorants are introduced into the melt in a dry form, ammonium nitrate is not stained.

The peculiarity of introducing organic substances into ammonium nitrate is that there are strict restrictions on the content of organic substances in solutions and in the melt of ammonium nitrate, since organic substances can initiate the thermal decomposition of ammonium nitrate during evaporation of the concentrated solution and subsequent transportation of the melt. For safe process control, the content of organic substances in the ammonium nitrate solution before the evaporation stage and in the transported melt should not exceed 0,0008% (8 mg / kg) in terms of the finished product. Ammonium nitrate solutions contain from 3 to 6 mg / kg of organic substances; in addition, no more than 2 mg of organic coloring substances per 1 kg of the finished product can be added to these solutions. However, when this amount of coloring agents is introduced into the ammonium nitrate solution, it is impossible to obtain granular products with a characteristic distinctive color of the granules.

In the proposed method for dyeing ammonium nitrate for technical purposes, organic coloring substances are introduced into the melt of ammonium nitrate immediately before its granulation, that is, after the stages of evaporation and transportation of the melt. In this case, the time from the moment organic substances enter the melt to its crystallization and cooling of the obtained granules is several seconds; therefore, the initiation of thermal decomposition of the melt is not observed.

Upon receipt of porous ammonium nitrate, organic coloring agents are introduced into the melt immediately before granulation as part of a pore-forming or surfactant additive. Organic colorants are added to the pore-forming and surfactant in dry form or administered as an aqueous solution or suspension. The concentration of coloring substances in the composition of the pore-forming and surfactant additives is calculated based on the dosage of these additives in the melt of ammonium nitrate and the required amount of coloring substance in the finished product.

Upon receipt of granular high-density ammonium nitrate, organic coloring substances are introduced into the melt immediately before granulation in the form of an aqueous solution or suspension. The dosage of aqueous solutions and suspensions is calculated based on their concentration and the required amount of coloring substances in the finished product.

As organic coloring substances, organic dyes are selected that meet the following requirements:

- retain their color when dissolved or dispersed in a solution or suspension of a pore-forming additive or in a solution of a surface-active additive;

- do not discolor in the melt of ammonium nitrate at temperatures up to 190 ° C;

- evenly granulate ammonium nitrate granules when introduced into the melt in an amount of 10-100 mg per 1 kg of the finished product;

- retain their color during the warranty period of storage of ammonium nitrate for technical purposes.

Despite these stringent restrictions, the existing dye market allows you to choose dyes that meet these requirements.

The color and color intensity of the granules of ammonium nitrate depend on the color and amount of the coloring matter introduced into the melt. The color of the finished product is evaluated visually. The color and quantity of a coloring agent for coloring a particular brand of ammonium nitrate is selected for technical purposes based on a visual assessment of the color and color intensity of the resulting granular product.

To obtain a uniformly colored ammonium nitrate for technical purposes with a characteristic distinctive color of the granules, 10-100 mg of coloring substances per 1 kg of the finished product is introduced into the melt of ammonium nitrate.

The introduction into the melt of ammonium nitrate of less than 10 mg of coloring substances per 1 kg of the finished product cannot provide uniformly colored granules with a characteristic distinctive color, since it is possible to obtain granules that are not uniform in color.

Putting more than 100 mg of coloring substances per 1 kg of finished product into the melt of ammonium nitrate is impractical, since already 10-100 mg of coloring substances per 1 kg of finished product provide the required uniform uniform coloring of granules, and an increase in the number of coloring substances leads to an increase in production costs products.

Technical result achieved:

- obtaining uniformly colored granular ammonium nitrate for technical purposes with a characteristic distinctive color of the granules of the required intensity;

- improving the consumer properties of the resulting products due to the coloring of granules;

- the ability to distinguish grades of granular ammonium nitrate for technical purposes in appearance, to distinguish the company's products from similar products of other manufacturers and from ammonium nitrate intended for agriculture.

The proposed method was tested in laboratory and industrial conditions using technological environments of the ammonium nitrate workshop, in particular, ammonium nitrate melt, pore-forming and surfactant additives. As coloring additives, various organic dyes have been selected. Trade names for dyes and test results for staining ammonium nitrate are given in the examples and in the table.

Example 1 (control experiment 1).

Pore-forming and surface-active additives are not introduced into the melt of ammonium nitrate, the melt of ammonium nitrate is granulated. The obtained granular high-density ammonium nitrate is a homogeneous white product with a beige tint (control sample of high-density ammonium nitrate).

Example 2 (control experiment 2).

Immediately before granulation, pore-forming and surfactant additives are introduced into the melt of ammonium nitrate. Ammonium nitrate melt is granulated. The obtained granular porous ammonium nitrate is a homogeneous white product with a beige tint (control sample of porous ammonium nitrate).

Example 3

Directly before granulation, dye cratacryl red-violet 4K is introduced into the ammonium nitrate melt in the form of a 5% aqueous solution based on the dye content in the finished product 50 mg / kg. Ammonium nitrate melt is granulated. The obtained granular high-density ammonium nitrate is a uniform, uniformly colored product with a characteristic distinctive color. The granules are saturated red with a purple hue.

Other examples are presented in the table. Depending on the chosen dye and its dosage, products with a characteristic distinctive color of the granules of the required intensity are obtained.

Upon receipt of high-density ammonium nitrate (examples No. 3, 4), the dyes are introduced into the melt before granulation in the form of an aqueous solution or suspension. Upon receipt of porous ammonium nitrate, dyes are introduced as part of a pore-forming additive (examples No. 5-9) or a surface-active additive (example No. 10).

Test results for staining ammonium nitrate for technical purposes N p / p The name of the dye The dye concentration in the finished product, mg / kg Putting dye into the melt The dye concentration in the feed solution,% The appearance of the granules of the finished product one 2 3 four 5 6 one No dye (control sample of high-density ammonium nitrate) 0 Dye is not administered Homogeneous white product with a beige tint 2 No dye (control sample of porous ammonium nitrate) 0 Dye is not administered Homogeneous white product with a beige tint 3 Organic dye Cratacryl red-violet 4K fifty Dry dye is previously dissolved in water and introduced into the melt before granulation in the form of an aqueous solution 5 Homogeneous product in rich red with a violet hue four Hansa RED GG fifty The dye is introduced into the melt before granulation in the form of an aqueous suspension fifteen Homogeneous product in saturated red with an orange tint 5 Acid dye bright red 4G one hundred Dry dye is previously dissolved in a solution of a pore-forming additive and introduced into the melt before granulation in the composition of a pore-forming additive 2.5 Homogeneous product in deep pink with orange tint 6 Acid dye bright red 4G 40 one Homogeneous pink product with orange tint 7 Acid dye bright red 4G 10 0.35 Homogeneous product light pink 8 Direct dye turquoise lightfast K fifteen 0.2 Homogeneous blue product 9 Active dye bright red C beef 60 2 Homogeneous product in bright pink 10 Dye Cratacryl red 2C thirty Dry dye is pre-dissolved in a solution of a surface-active additive (NF dispersant) and melted before granulation as part of a surface-active additive Homogeneous pink product with a bluish tint

Claims (2)

1. The method of dyeing ammonium nitrate for technical purposes, which consists in the fact that the granulation of the melt of ammonium nitrate is carried out in the presence of organic coloring substances introduced into the melt immediately before granulation in the composition of the pore-forming or surfactant additives or in the form of an aqueous solution or suspension in an amount of 10 -100 mg per 1 kg of the finished product. 2. The method according to claim 1, characterized in that dyes that do not discolor when the ammonium nitrate is melted at temperatures up to 190 ° C are selected as organic coloring substances.