RU2456045C2 - Method for obtaining extinguishing powder composition - Google Patents

Abstract

FIELD: fire-fighting means.

SUBSTANCE: invention relates to methods for producing fire extinguishing powder compositions for extinguishing fires of Class A, B, C, and electric installations under voltage up to 1000 V in various sectors of the economy and everyday life. A method of producing fire extinguishing powder composition includes grinding of the composition components and their mixture, and the ammonium phosphate and ammonium sulphate are ground separately in the presence of silicon dioxide and polyorganosiloxane hydride, then product based on ammonium phosphate is subjected to sieving with the release of 35-60 micron size fraction, and on the basis of ammonium sulfate size of 60-140 microns, respectively, and then the products sieved are mixed to obtain the composition with the following mass ratio of the components: ammonium phosphate and ammonium sulfate: silicon dioxide: polyorganosiloxane hydride 90-97.25: 2.5-5: 0.25-5%.

EFFECT: method provides high parameters of fire extinguishing and water repellency parameters, namely, a low tendency to water absorption, high capacity for water repellency and high apparent bulk density, and also prevents formation of incrustations and sticking of refinable components to the walls of the grinding equipment.

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Description

FIELD OF TECHNOLOGY

The invention relates to methods for producing fire extinguishing powder compositions for extinguishing fires of classes A, B, C and electrical installations under voltage up to 1000 V, in various sectors of the national economy and in everyday life.

BACKGROUND

A known method of obtaining a fire extinguishing powder composition (OPS), where as the main component is used pre-ground potassium chloride. The method includes processing the ground potassium chloride with alkyl halosilanes in the vapor phase at 80-120 ° C with preliminary air supply with an absolute moisture content of 60-70 g / m ³ (RF patent 2050876, A62D 1/00, publ. 1995).

The disadvantage of the analogue is the high caking and water absorption of the resulting fire extinguishing powder composition.

There is also known a method of producing OPS, including the possibility of obtaining fractions of 50-100 microns - 30% and less than 50 microns - 70%. According to this method, after the stages of sifting, grinding and hydrophobization, the main component (potassium chloride) is calcined in an aerosil medium at 80-155 ° C for 2.5-4.5 hours, followed by sieving after the calcination stage. The method allows to obtain OPS with high hydrophobicity, while the normalized particle size increases the fire extinguishing ability of the powder (RF patent 2170601, A62D 1/00, publ. 20.07.2001).

A significant disadvantage of this method is the high cost of dispersed additives - Aerosil, which reduces the competitiveness in the market of fire extinguishing agents.

The closest to the proposed invention in terms of technical nature and the achieved result, that is, the prototype, is a method for producing OPS, including drying all the components, hydrophobizing used as an anti-caking additive of soot with organosilicon substances, which is carried out in the process of grinding, followed by temperature control at a temperature of 70 -100 ° C for 2-4 hours; grinding the main components with the addition of 20-40% of the total mass of hydrophobized white soot and mixing all the components of the composition. As the main target components use a mixture of ammonium sulfate and ammonium phosphate in a ratio of 1: 1. In the composition of the extinguishing powder, the target components are 95 wt.%., The total mass of white soot and organosilicon liquid is 5 wt.% (The content of white soot is 95-99 wt.% Of their total mass, and organosilicon liquid is 1-5 mass .%) (RF patent 2302889, A62D 1/00, publ. 20.07.2007).

The disadvantages of the prototype should include a rather high tendency to moisture absorption and a low ability to thaw and insufficient apparent bulk density. In addition, the disadvantage of this invention is the inability to obtain a powder with an optimal ratio: the quenching fraction from 35 to 60 μm (ammonium phosphate) and the carrier fraction from 60 to 140 μm (ammonium sulfate), since both phosphate and ammonium sulfate are crushed together with anti-caking additive.

SUMMARY OF THE INVENTION

The objective of the invention is to provide a method for producing fire extinguishing powder for multi-purpose with high fire extinguishing parameters and indicators of hydrophobicity, namely, a low tendency to moisture absorption, high ability to water repellent and high apparent bulk density. Fire extinguishing powder is produced with a certain fractional composition of the carrier and the quenching fraction, as well as the lowest consumption of hydrophobic organosilicon liquid, without compromising the quality of the finished product.

To solve this problem, a method for producing a fire extinguishing powder composition has been developed, including grinding ammonium phosphate and sulfate with silicon dioxide and polyorganohydride siloxane, followed by mixing all the components of the composition, in which grinding is carried out separately at a mass ratio of ammonium phosphate or ammonium sulfate: silicon dioxide: polyorganohydride siloxane equal to 90 ÷ 97.25: 2.5 ÷ 5: 0.25 ÷ 5%, after which the products are subjected to separate sieving with the selection of fractions based on ammonium phosphate size 35 ÷ 60 and based on ammonium sulfate with a size of 60 ÷ 140 microns, respectively.

The grinding of ammonium phosphate in the presence of silicon dioxide and organosilicon liquid is carried out in a roller ring vibratory mill with shock-shear loading. The grinding of ammonium sulfate is carried out in a disintegrator mill, followed by classification and selection of fractions of a certain size. At the final stage, all the components of the extinguishing powder are mixed in full.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

Example 1

Ammonium phosphate in an amount of 95.76 g is ground in a vibratory mill in the presence of 5.32 g of silicon dioxide and 5.32 g of polymethylhydride siloxane to a fraction content of not more than 60 microns and not less than 35 microns. Ammonium sulfate in an amount of 95.76 g is crushed in a disintegrator mill in the presence of 5.32 g of silicon dioxide and 5.32 g of polymethylhydride siloxane to a fraction of not more than 140 microns and not less than 60 microns. At the final stage, all components are fully mixed in a mixer. Product Composition: Ammonium Phosphate - 45.00%; ammonium sulfate - 45.00%; silicon dioxide - 5%; polymethylhydride siloxane - 5%.

Example 2

Ammonium phosphate in an amount of 100 g is crushed in a vibrating mill in the presence of 4.26 g of silicon dioxide and 2.13 g of polydiethylhydridosiloxane to a fraction of not more than 60 microns and not less than 35 microns. Ammonium sulfate in an amount of 100 g is crushed in a disintegrator mill in the presence of 4.26 g of silicon dioxide and 2.13 g of polydiethylhydride siloxane to a fraction of not more than 140 microns and not less than 60 microns. At the last stage, all components are fully mixed. Product Composition: Ammonium Phosphate - 47%; ammonium sulfate - 47%; silicon dioxide - 4%; polydiethylhydride siloxane - 2%.

Example 3

Ammonium phosphate in an amount of 103.5 g is ground in a vibratory mill in the presence of 2.66 g of silicon dioxide and 0.26 g of polyethylsiloxane to a fraction of not more than 60 μm and not less than 35 μm. Ammonium sulfate in an amount of 103.5 g is ground in a disintegrator mill in the presence of 2.66 g of silicon dioxide and 0.26 g of polyethylsiloxane to a fraction of not more than 140 microns and not less than 60 microns. At the last stage, all components are fully mixed. Product Composition: Ammonium Phosphate - 48.62%; ammonium sulfate - 48.62%; silicon dioxide - 2.5%; polyethyl hydride siloxane - 0.25%.

Indicators of apparent bulk density, a tendency to moisture absorption and the ability to repel water of the obtained samples were determined using the methods presented in the fire safety standards “General Purpose Fire Extinguishing Powders. General technical requirements. Test Methods ”(NPB-170-98).

The test results are presented in the table.

Table Example No. Name of indicator The tendency to moisture absorption,% Water repellent, min Apparent bulk density, kg / m ³ loose powder compacted powder one 0.78 more than 260 820 1110 2 0.80 more than 200 800 1100 3 0.69 more than 260 830 1140 Prototype 1,57 more than 180 720 1100

The table shows that the use of the invention allows to obtain a fire extinguishing powder, with a lower tendency to water absorption and higher water-repellent ability compared to the prototype. In this case, the apparent bulk density of the obtained samples is on average higher than the density of the prototype by 13.25%.

In addition, the proposed method eliminates the formation of inlays and the adhesion of crushed components on the walls of grinding equipment, which is an additional advantage.

Claims (1)

A method of obtaining a fire extinguishing powder composition, comprising grinding the components of the composition and mixing them, characterized in that the phosphate and ammonium sulfate are crushed separately in the presence of silicon dioxide and polyorganohydride siloxane, then the product based on ammonium phosphate is sieved with a fraction of 35 ÷ 60 μm and based on ammonium sulfate with a size of 60-140 microns, respectively, after which the sifted products are mixed to obtain a composition with the following mass ratio of components: ammonium phosphate and sulfate a mmonium: silicon dioxide: polyorganohydridesiloxane 90 ÷ 97.25: 2.5 ÷ 5: 0.25 ÷ 5%.