SU1583631A1 - Method of localizing and extinguishing fire in mine working - Google Patents

Abstract

FIELD: fire fighting. The goal is to increase the efficiency of localization and extinguishing fires. Fire zones are divided into areas of fire extinguishing with fire dampers. A flame retardant carbamide-formaldehyde oligomer filled with crushed sedimentary rocks taken in a quantity of 50-100 wt.h. per 100 wt.h. urea-formaldehyde oligomer. The flame is affected by flame extinguishing agents. The volume of each fire barrier is 20-30% of the overlapped production cross section. Urea-formaldehyde hardening foam is obtained directly at the site of use by mixing urea-formaldehyde oligomer, anionic type surfactant, gasifier with crushed sedimentary rocks and further curing the composition in the presence of an acid catalyst containing waste after drying the coke oven gas. The high fire resistance of the damper allows it to withstand prolonged high-temperature exposure. 1 hp f-ly, 1 tab.

Description

The invention relates to fire fighting and can be used in extinguishing and localizing foci of heterogeneous combustion.

The aim of the invention is to increase the efficiency of fire localization and extinguishing.

The essence of the method lies in the fact that the fire zone is divided into areas of fire extinguishing and at the interface section barriers are made of soles of blocks made of hardening urea-formaldehyde foam filled with sedimentary rocks.

In the event of a fire, the temperature of the air and the walls of the room increases. When the ambient temperature reaches 175-250 ° C, the hardening carbamide-formaldehyde foam expands. Within a few minutes, it increases in volume by a factor of 3-5 or more, filling the space covered by the barrier. In this case, the fire is localized, since the expanded hardening foam has a high fire resistance. In the process of expansion under the action of high temperatures, the hardening foam softens

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with

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body and is in flowing state, filled with equipment cluttered areas or irregularities of the section,

Fire extinguishing after overlapping a site with a barrier of expanded hardening foam is carried out by supplying flame-retarding agents to the fire center or by means of self-suppression of burning gaseous products that fill the fire-extinguishing area.

Urea-formaldehyde hardening foam is obtained directly at the site of use by mixing carbamide still-lifedehyde oligomer, anionic type surfactant, gasifier (alkaline earth metal carbonates) with crushed sedimentary rocks and further curing the composition with the presence of an acid catalyst containing waste after drying the coke-oven gas. In this case, the alkaline-earth metal carbonides react with the acid catalyst, as a result of which carbon dioxide is released, which foams the composition. The composition cures within minutes. The sedimentary rocks introduced into the composition are distributed in the polymer cellular skeleton, reducing the flammability of the cured foam material.

The introduction of crushed sedimentary rocks significantly affects the properties of urea-formaldehyde foam, namely, it provides an effect of swelling under the influence of flame and strong heat fluxes. This is due to the fact that sedimentary rocks are saturated with water, which is contained in them in the form of chemically bound (crystallization) and physically bound, i.e. closely connected with (verdaceous rock particles. In addition, sedimentary rocks, having a high adsorption capacity, concentrate (adsorb) on their surface water contained in a urea-formaldehyde oligomer. When the temperature rises to G / L 2 O ° 1, the polymer binder the foamed composition is softened and water is vaporized, which leads to swelling of the furnace material and an increase in

in and more times.

The starting products for the preparation of hardening carbamide-formaldehyde foam are carbamide-maldehyde resins of the grades KF-B, KF-Z, KF-MT, carbonates of alkaline-earth metals - chalk or inert dust with hydrophobic additives, anionic surfactant - sulfonol NP-3 or Progress (to enhance the foaming effect and the acid curing catalyst is a VAG-3 product containing coke production waste after drying the coke oven gas. The filler, crushed sedimentary rocks, is introduced in an amount of 50-100 parts by weight mac.carbamide-formaldehyde oligomer.

Introduction to the composition of less than 50 ma.ch. crushed sediment degrades swelling. The increase in the content of rocks in the composition of more than 100 ma.ch. It is impractical because it impairs the processability of the process of obtaining a hardening foam and reduces its multiplicity, which leads to an increase in the consumption of the raw material and the higher cost of the composition.

An example. In order to protect the underground conveyor line 2500 m from fires arising on the linear part of the conveyors, the proposed method of localizing and extinguishing fires is used. The mine workings in which the belt conveyors were housed were fastened with metal arches with reinforced concrete ones, i.e. fireproof lining. Combustible materials-t-rubber conveyor belt and angle transported along it, as well as coal plug, spilled onto the soil, the conveyor line is divided into 25 areas of fire-extinguishing fires: equipped at a distance of about 100 m from each other. Fireproof barriers are sections of generation of length m, across which, across 0.5 m, rows of metal wire are stretched horizontally over the upper branch of the conveyor and in the interval between the upper and lower ones. Blocks of foam that swell when heated are worn on the wire. The foam also covers the soil of the excavation above the conveyor during the barrier.

I The intumescent foam is made from chemically foamed hardened oligomer. The composition of the original ingredients is the following, ma.ch .:

Urea formaldehyde oligomer100

Surfactant anionic type2

Carbonates of alkaline earth metals 12 Condensate after drying

1583631

To give the ability to swell when heated and reduce flammability, crushed sedimentary rocks are added to the composition to make foam.

Results of property research

When equipping fireproof gates, Composition 3 is used, which is filled with 30% of the mine workings during the gate.

In the event of a fire in one of the fire extinguishing sites, the fire spreads only to the gate closest to the ventilation jet. Due to the heating of the fire gases of the foam to 210-250 0, it begins to swell. Having increased by 3-4 times the volume, the foam overlaps the cross section of the mine work, localizes the fire and stops its air supply. The swelling block of chenes has the ability to solder with adjacent blocks, and the choke becomes less permeable to gases. Therefore, the burning intensity of the coal and the conveyor belt is sharply reduced due to lack of oxygen. The final extinguishing of the fire is carried out by acting on the combustion center with fire extinguishing agents — water from a fire and irrigation pipeline and a fire extinguishing powder from hand-held and mobile fire extinguishers. High fireproof barrier will allow Compose

Editor 0. Yurkovetska

Tehred L. Oliynyk

Order 2240 Circulation 377 Subscription

VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5

It can withstand prolonged high-temperature exposure, therefore, even with late detection of fire, extinguishing occurs arbitrarily by burning out the fire load in the area of extinguishing between two adjacent dampers.

Claims (2)

1. A method of localizing and extinguishing a fire in the workings, including dividing the fire zone into fire extinguishing fire extinguishing areas and exposing the fire center to a flame maker with means, characterized in that filled with crushed sedimentary rocks, taken in an amount of 50-100 wt. on 100 ma.ch. urea formaldehyde oligomer. 2. A method according to claim 1, characterized in that the volume of each fire barrier is 20-30% of the overlapped production section of I. Fedova Proofreader M. Sharoshi