RU2230726C2 - Aerosol generation pyrotechnic composition for systems performing volumetric fire-extinguishing - Google Patents

Abstract

FIELD: fire-fighting, particularly aerosol generating compositions.

SUBSTANCE: aerosol generation composition comprises potassium nitrate, iditol and cyanuric acid as fuel material. Composition may include urea as additional fuel material.

EFFECT: increased efficiency of fire-extinguishing, reduced temperature of aerosol composition combustion without substantial increase of combustion product toxicity.

2 cl, 2 tbl

Description

The invention relates to the field of aerosol generating pyrotechnic compositions for volumetric fire extinguishing systems [1, 2]. The essence of the action of this type of fire extinguisher is that the combustion products of the pyrotechnic composition, entering the fire zone in the room, cause its localization and extinguishing.

Known fire extinguishing composition based on potassium nitrate, a polymer binder and iditol [2, 3]. Its main disadvantages are low fire extinguishing efficiency and low density.

Close to the proposed composition is an aerosol generating composition according to the patent [4]. Its main physical, chemical and operational characteristics are given in tables 1 and 2.

In accordance with [4] it contains potassium nitrate, fuel, binder and catalyst in the following components, wt.%:

Potassium Nitrate 68.5-73.5

Dicyandiamide 22-24

Iditol 1.5-2.5

Fe ₂ O ₃ 3-5

The disadvantage of this composition is the high combustion temperature (table 2), which requires the use of a special cooler to reduce it, because Hot combustion products can be dangerous for people and animals in the aerosol generator. The use of coolers significantly worsens the weight and size characteristics of the aerosol generator and leads to an increase in its cost.

In addition, due to the low binder content, this composition has insufficient strength for real conditions of practical application.

An important technical characteristic of an aerosol-generating composition is fire extinguishing efficiency [2], which shows what is the minimum amount of composition required to extinguish a fire per unit volume of a protected room. This characteristic of the prototype is not high enough for modern compositions.

Given the importance of fire extinguishing systems of this type, which are actively developing in recent years, it is necessary to improve aerosol-generating compositions, eliminating the above disadvantages. In this regard, it is necessary to develop a new composition, which could provide a higher level of quality of technology.

To solve this problem, compositions have been developed that include potassium nitrate, iditol and cyanuric acid as fuel with the following components, wt.%:

Cyanuric acid 15-26

Iditol 1-12

Potassium Nitrate Else

As an additional fuel composition may contain urea, with the following components, wt.%:

Cyanuric acid 15-26

Urea 1-12

Iditol 1-12

Potassium Nitrate Else

Samples of the proposed compositions were manufactured and tested at IPCP RAS. In the preparation of compositions, the components were mixed and molded in the form of pieces by pressing in accordance with the accepted technology of pyrotechnic compositions [5, 6]. To measure the combustion characteristics and the effectiveness of the proposed compositions, experiments were conducted on volumetric quenching of the flame of hydrocarbon fuel in a closed volume by a standard method [2]. Examples of compositions, information on their physicochemical properties, burning rate and quenching concentrations are presented in Tables 1 and 2.

The above limits for the content of cyanuric acid and iditol are due to the maximum efficiency of the composition, the conditions of its combustion and the strength of the charge. When the content of cyanuric acid is less than 15 wt.% And more than 26 wt.%, The composition loses a significant part of its effectiveness.

With an iditol content of less than 1 wt.%, It is difficult to provide an acceptable charge strength. When the iditol content is more than 12 wt.%, Quenching efficiency sharply decreases, the content of toxic products increases, and the burning rate of the composition decreases. The presence of urea in an amount of more than 12 wt.% Leads to the fact that independent stable combustion of the composition becomes impossible.

[7]) по сравнению с используемым в аналоге дициандиамидом (

[8]) и меньшая потребность в кислороде при ее окислении позволили снизить температуру горения состава не увеличивая существенно токсичность первичных продуктов его сгорания. Таким образом, новые составы, имея температуру продуктов сгорания на 300-700°С меньше, чем у аналога, позволят упростить и удешевить конструкцию установки аэрозольного пожаротушения.The proposed composition is more effective than the prototype for volumetric extinguishing of a hydrocarbon flame. Significantly lower heat of formation of cyanuric acid (

[7]) compared to dicyandiamide used in the analogue (

[8]) and a lower need for oxygen during its oxidation made it possible to lower the combustion temperature of the composition without substantially increasing the toxicity of its primary combustion products. Thus, the new compositions, having a temperature of combustion products 300-700 ° C lower than that of the analogue, will simplify and reduce the cost of the design of aerosol fire extinguishing systems.

Sources of information

1. B.P. Zhukov. Gunpowder, pyrotechnics and special solid fuels in the fight against fires. Materials of the Scientific Council under the Presidium of the USSR Academy of Sciences. - M.: NPO InformTEI, 1991, pp. 4-10.

2. V.N. Alikin, G.E. Kuzmitsky, A.E. Stepanov. Autonomous solid fuel aerosol fire extinguishing systems. - Perm, PNC UB RAS, 1998, 148 p.

3. A.D. Sergienko, G.E. Kuzmitsky, A.E. Stepanov. Aerosol-forming solid fuel composition for fire fighting. RF patent No. 2080137.

4. RF patent No. 2060743.

5. A.M. Korobkov, A.M. Novtsov. Pyrotechnic compositions and their preparation. Brief Encyclopedic Dictionary of Condensed Energy Systems. - M.: Janus-K, 1999, p. 370.

6. A.M. Korobkov, A.M. Novtsov. The formation of pyrotechnic elements. Brief Encyclopedic Dictionary of Condensed Energy Systems. - M .: Janus-K, 1999, p. 372.

7. Chemical encyclopedia. - M .: Chemistry, 1998, v. 5, p. 708.

8. Chemical encyclopedia. - M .: Chemistry, 1998, v.2, p.205-206.

Claims (2)

1. Aerosol-generating pyrotechnic composition for volumetric fire extinguishing systems, including potassium nitrate, iditol and fuel, characterized in that it contains cyanuric acid as fuel in the following components, wt.%: Cyanuric acid 15-26 Iditol 1-12 Potassium Nitrate Else 2. Aerosol-generating pyrotechnic composition for volumetric fire extinguishing systems according to claim 1, characterized in that it contains urea as additional fuel with the following components, wt.%: Cyanuric acid 15-26 Urea 1-12 Iditol 1-12 Potassium Nitrate Else

Images