SU1236111A1 - Method of preventing and extinguishing endogene fires - Google Patents

Description

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The invention relates to methods for preventing and extinguishing endogenous fires that have occurred in coal mines using inert suspensions.

The purpose of the invention is to increase the efficiency of preventing and extinguishing endogenous fires by improving foam quality, increasing the distance of its transportation through the pipeline and collapsed rocks, and increasing the performance of HarHeTaTiHH.

The drawing shows a technological system for preparing and supplying a suspension to an endogenous fire site.

The system contains hermetic tanks 1 and 2 with pumps 3 and 4, supply pipes 5 and 6 of the foaming agent solution and pipelines 7 and 8 with carbon dioxide saturated solution, liquid nitrogen tank 9 with flow meter 10, recipient 11 carbon dioxide with pipelines 12 and 13 delivery, generator 14 inert foam, hopper 15 of foaming powder composition with dispenser 16 supply, ejector mixer 17, pipe 18 for supplying foam foam aqueous solution, pipeline 19 for inert foam and pressure gauges 20 and 21. Pipeline 18 for supplying aqueous solution and the frother is equipped with a shut-off valve 22, pipelines 5 and 6, supplying tank 1 and 2 with valves 23 and 24, pipelines 12 and 13, supplying carbon dioxide to tank 1 and 2 with valves 25 and 26, and pipelines 7 and 8 of the delivery of the finished solution - valves 27 and 28,

The system diagram contains an underground mining excavation 29, an insulating bridge 30 and collapsed rocks 31 of the excavated space.

The method is carried out as follows.

The tank 1 at the opening of the valves 22 and 23 through the pipes 18 and 5 is filled with an aqueous solution of the foaming agent, then the valves are closed and, when the valve 25 is open, the pipeline 12 provides the gaseous carbon dioxide gas from the recipient 11 under pressure, while the carbon dioxide the gas is dissolved in the aqueous frother solution until it is saturated. Saturated solution by pump 4 through the pipeline 7 with the valve 27 open is fed to the generator 14 while simultaneously supplying

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liquid nitrogen from tanks: 9 through flowmeter 10 „

Liquid nitrogen entering the water flow of the foaming agent solution, due to high heat exchange, instantly evaporates to form a large number of bubbles, which, mixing with the foaming agent solution, form an inert foam with a finely cellular structure that is sufficiently stable. Formed with foam drops into ejector mixer 17 and due to dilution when dispenser 16 is on, it provides a predetermined batch feed of foam generating powder (GWP) from bunker 15. Formed with a mixture (suspension) enters foam pipe 19 and further into a mountain underground mine 29 and in the collapsed rocks of 31, isolated by lintel 30 of the emergency site. When the inert (nitrogen) foam moves along the foam pipe 19, the foam powder is dissolved, carbon dioxide is released, which redistributes the foam flow, increases its volume, improves the structure and provides the resulting increase in pressure, and the powder supply provides a pulsating flow of foam flow. that according to the laws of hydrodynamics reduces the resistance of the pipeline and increases its throughput.

The foam produced from the standard GWP powder consists of 80% carbon dioxide, 19.7% aqueous solution and 0.3% foaming agents. The multiplicity after 60 minutes is 4, and after 10 minutes - at least 6,

It contains A2 (alumina sulphate) alumina (O) s (acid part

63%), sodium bicarbonate NaHCO (w, herringbone part 33.7%) and licorice extract (3.3%), Foam-producing powder has well recommended itself to the practice of extinguishing fires with foam.

Getting into the collapsed rocks of the worked-out space, at the exit of the foam pipe 19, the overpressure pa / gives, as a result, the dissolved gas is rapidly released from the liquid phase of the foam and its thickened walls, provides an improvement in the structure of the foam flow, expands its volume and volume, Redistributed Flow penetrates through the collapsed rocks, fill the developed space.

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In order to ensure a continuous supply of inert foam, the system is equipped with a tank 2. When the tank 1 is consumed, the tank 2 is switched on.

The proposed method, in comparison with the known ones, allows to reduce the resistance of the pipeline due to the periodic reduction of the pressure in the foam pipe by batching the foaming powder; increase the flow capacity of the pipeline due to the increase in pressure and time of stabilization of the foam flow,

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to increase the stability, multiplicity and productivity of foam injection, as well as to increase the distance of foam flow transportation through wells, pipelines and collapsed rocks of the developed space due to the remote redistribution of foam flow.

In addition, the carbonated carbonated aqueous solution of the frother is less susceptible to freezing, which allows an increase in the supply of liquid nitrogen.

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Editor 0. Golovach

Compiled by I. Fed eva

Tehred L. Serdyukova Proofreader E. Sirohman

Order 3074/33 Circulation 436Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Claims (1)

METHOD FOR PREVENTING AND EXTINGUISHING ENDOGENOUS FIRES with inert foams, including supplying a gas-saturated under pressure foaming solution through pipelines and wells to the emergency section of the worked out part of the formation, characterized in that, in order to increase the efficiency of preventing and extinguishing endogenous fires by improving the quality of the foam, increasing the range its transportation and increase the discharge rate, liquid nitrogen and foam generator are additionally introduced into the stream of the gas-saturated foam-forming solution a torus powder having a delayed dissolution reaction with evolution of a gaseous reaction product. S