EP2540351B1 - Method and device for quenching oil and petroleum products in tanks - Google Patents

Description

The invention relates to a tank extinguishing method for extinguishing petroleum fires according to the preamble of claim 1.

The invention can be used in fire protection technology. It provides a method for extinguishing petroleum and oil product fires, flammable liquids (combustible liquids) and highly flammable liquids in steel-fired tanks (SHT) and steel high-tonnage pontoon (SHTP) tanks.

From the publication RU 1687266 from 30.10.91 a method for extinguishing burning liquids is known. According to this method solid crushed carbon dioxide with a diameter of 3 - 4 cm of the granules to the source of the fire fed. The granules are fed as compact sets under the layer of the burning liquid. The shortcomings of the process of extinguishing the burning liquids by means of the solid carbon dioxide include difficult feeding of dry ice to the burning tank via process-loading piping and high consumption for fire fighting (at least 0.7 kg / m ³ ) and for storage in thermal tanks.

• ein erhöhtes spezifisches Gewicht der Einrichtung gegenüber dem Gewicht ihrer Löschmittelladung;
• ein hoher Druck (100 MPa) und eine hohe Temperatur (1500 - 2000° C) in der Gaserzeugungszelle;
• ein Hochdruck (10 MPa) im Gehäuse des Feuerlöschers;
• eine Unhandlichkeit dieses Löschverfahrens wegen zu hoher Ausströmgeschwindigkeit (bis zu 250 m/Sek.) des Feuerlöschmittels und eine erhöhte Gefährdung für das Bedienpersonal.

There is also known a gas powder extinguishing method from a powder fire extinguisher for local fire fighting. It contains a bottle gun with fire extinguishing powder, a gas generating cell with an explosive charge and a trigger cartridge, as well as an automatic control and monitoring system. This fire extinguisher complies with the guidelines VNIIPO MVD RF ( All-Russian Scientific Research Institute for Fire Protection, Ministry of Internal Affairs RF of the USSR, 1978, pp. 12, 16, 30, figs. 5 and 4 ) refer to. The shortcomings of this procedure are:

• an increased specific weight of the device relative to the weight of its extinguishing agent charge;
• a high pressure (100 MPa) and a high temperature (1500-2000 ° C) in the gas generating cell;
• a high pressure (10 MPa) in the body of the fire extinguisher;
• a clumsiness of this extinguishing method due to high outflow speed (up to 250 m / sec.) Of the fire extinguishing agent and an increased risk to the operator.

The patent RU 2129031 of 18.08.92 describes a fire extinguishing method according to which the burning surface is controlled with an aerosol-forming solid fuel in the form of foam granules or foam fog bodies with a specific weight of 800 kg / m ³ . The foam granules or the foam fog bodies are coated with a moisture protection agent. The ignition temperature of the moisture protection agent is 120-140 ° C. The moisturizer is manually fed according to the invention (the bags of foam granules are thrown down onto the burning surface of the oil tank) or through a hose from the tanker.

In the opinion of the inventors, this method is virtually impossible to carry out in practice, since the supply of a solid-fuel or pyrotechnic extinguishing agent with the above-mentioned characteristics of the surface of the burning tank is extremely dangerous, especially if the focal surface is 375 m ² , The tank diameter of an SHT-5000 tank is 21.1 m, and the focal area is 356 m ² . The height of the flame is approximately 1 to 2 times the tank diameter in petroleum fires. Thus, the flame circumference at 21.1 m (tank diameter) high flames will be 7511.6 m ³ . According to the description, 24 kg foam granules with a diameter of 8 to 10 mm and a density of 600 kg / m ^{3 will} cover only 1% of the total burning surface. The achievable aerosol concentration (assuming that the extinguishant utilization coefficient equals one) will then be 24,000 g: 7511.6 m ³ = 3.19 g / m ³ , while Inventors C _Erase. = 63 g / m ³ .

Taking into account that the amount of the excreted gases is 1600 times the size of the foam frustum bodies, the amount of combustion products will reach 64 m ³ . This makes up 0.85% of the flame circumference. Such extinguishing agents with a fire extinguishing concentration of 3.19 g / m ³ or 0.85% (circumference) or 24 kg: 356 m ² = 0.067 kg / m ² are currently unknown. Consequently, this erasing method can be considered physically impossible.

From the patent RU 2096053 (A62C 2/00 dated 05.08.94) is another tank extinguishing method known. This method consists in the combustion of a solid fuel composition and in the supply of a cooled gas-aerosol mixture of the burning surface in the upward direction (from bottom to top). The cooling is done in 2 steps. First, the combustion products of the solid fuel composition are cooled in a pipeline.

For this, water or salt water solution is used. In the second step, the remainder (undissolved, not settled and non-condensed residue) of the gas-aerosol mixture is barbotiert over a layer of flammable or highly flammable liquid to the fuel surface. The specific consumption of the fire extinguishing agent with respect to the burning surface was 0.2 kg / m ² with a burning surface of 1 m ² , the volume of the highly inflammable liquid 0.75 m ³ and the column of highly inflammable liquid 0.75 m.

worin

σ_f

- den Koeffizienten der Oberflächenspannung der brennbaren Flüssigkeit;

ρ_g

- die Dichte der Verbrennungsgase;

H

- die Höhe der Flüssigkeitssäule über dem Barboteur;

P_a

- den atmosphärischen Druck;

g

- die Erdbeschleunigung;

a

- den Lochabstand L im Barboteur bedeuten. Der Lochabstand L wird wie folgt berechnet:

$$\mathrm{L}>{\left[\frac{6{\mathrm{d}}_0{\mathrm{\sigma }}_{\mathrm{f}}}{\mathrm{g}\left({\mathrm{\rho }}_{\mathrm{f}}-{\mathrm{\rho }}_{\mathrm{g}}\right)}\right]}^{1/3}*\left[\frac{\mathrm{H}{\mathrm{\rho }}_{\mathrm{f}}\mathrm{g}}{{\mathrm{P}}_{\mathrm{a}}}+1\right]$$

( s. Ya. E. Geguzin). Blasen.- M.: 1985 )The major drawbacks of this process are increased fire hazard (application of pyrophoric solid fuel compositions to higher fire hazard equipment), heat pyrolysis of petroleum and oil products by the combustion products, and relatively high fire extinguisher consumption in the barbotage of the gas aerosol blend in bulk SHT. For example, the SHT-5000 with a capacity of 5000 m ³ , which is most frequently used in the RF, has a mirror diameter of 22.8 m and a liquid column of 11.92 m. The mirror surface is 408 m ² . Thus, in order to evenly distribute the gas-aerosol mixture above the liquid level in SHT-5000 under nature conditions, in addition to the measures described in the patent, a tube unwind for barotaging the gas-aerosol mixture must be used. The diameter of the Barboteur holes is calculated as follows: $$4{\left[\frac{{\mathrm{\sigma }}_{\mathrm{f}}}{\mathrm{G}\left({\mathrm{\rho }}_{\mathrm{f}}-{\mathrm{\rho }}_{\mathrm{G}}\right)}\right]}^{1/2}\le {\mathrm{d}}_0<29\times \frac{{\mathrm{\sigma }}_{\mathrm{f}}{}^2\mathrm{G}\left({\mathrm{\rho }}_{\mathrm{f}}-{\mathrm{\rho }}_{\mathrm{G}}\right)}{{\mathrm{\rho }}_{\mathrm{f}}{\mathrm{\rho }}_{\mathrm{G}}{\left[\mathrm{H}{\mathrm{\rho }}_{\mathrm{f}}\mathrm{G}/{\mathrm{P}}_{\mathrm{a}}+1\right]}^3}$$

wherein

σ _f

the coefficient of surface tension of the combustible liquid;

ρ _g

- the density of the combustion gases;

H

the height of the column of liquid above the baroteur;

P _a

- the atmospheric pressure;

G

- the acceleration of gravity;

a

- Mean the hole distance L in the Barboteur. The hole spacing L is calculated as follows:

$$\mathrm{L}>{\left[\frac{6{\mathrm{d}}_0{\mathrm{\sigma }}_{\mathrm{f}}}{\mathrm{G}\left({\mathrm{\rho }}_{\mathrm{f}}-{\mathrm{\rho }}_{\mathrm{G}}\right)}\right]}^{1/3}*\left[\frac{\mathrm{H}{\mathrm{\rho }}_{\mathrm{f}}\mathrm{G}}{{\mathrm{P}}_{\mathrm{a}}}+1\right]$$

( s. Ya. E. Geguzin). Bubbles.- M .: 1985 )

According to the experimental data ( IV Belov, EV Prokolov. Movement speed and shapes of bubbles in the water // PMTF, Issue 3, 1968 ) is the emergence velocity of the bubbles on average u _Blas about 0.23 m / sec. at d _blows ≥ 2 mm.

The calculations show that the optimal diameter of the baroteur holes d ₀ = 3 mm and the hole spacing L = 9 mm (see patent RU 2126702 A62 C3 / 06). Thus, for the required fire-extinguishing effect in the SHT-5000 a Barboteur with 50000 holes is necessary.

The losses of fire extinguishing aerosol in pipelines and coolers are each up to 50% ( VV Agafonov, NP Kopylov. Aerosol fire extinguishing systems. M .: 1999. 302 p .). Under natural conditions, the actual consumption is in the end 0.8 kg / m. The delivery time of the gas-aerosol mixture to the surface with burning liquid is at least 2 minutes, taking into account the duration of the fire-extinguishing aerosol generator.

From the prior art is a tank extinguishing method for extinguishing easily flammable Liquids and flammable liquids according to the patent RU 2241508 known. According to this method, the burning area is extinguished by feeding the disperse fire extinguishing gas mixture (disperse gas mixture) to the fire area from the bottom to the top. The disperse fire extinguishing gas mixture is formed by the fact that a gaseous and / or liquefied gas phlegmatizer (combustion retarder) and / or a gaseous and / or liquefied homogeneous flame retardant and / or a hydrocarbon repellent surface active under a pressure of at least 2 MPa the container with a powdered or liquid heterogeneous flame retardant is supplied. The container is equipped with a valve which ensures the outlet of disperse gas mixture via a perforated spray nozzle or via several spray nozzles at a container pressure of at least 0.42 MPa. The perforated spray nozzles ensure an atomization of the dispersed gas mixture by 180 ° with a consumption of at least 1 kg / sec. The direction of atomization runs in the same direction as the surface of the burning liquid and in the upper hemisphere above the surface of the above-mentioned liquid. The sputtering intensity thereby ensures the concentration of the disperse gas mixture of at least 0.09 kg / m ³ in the middle of the flame above the burning surface. The mass ratio between the gas phase and the disperse phase of the fire extinguishing mixture is within 0.2: 1 to 15: 1. The gas component is an inert gas (eg CO ₂ , N ₂ , Ar or their mixture) and / or or an ozone-neutral halogenated hydrocarbon. The heterogeneous flame retardants used are a fire-extinguishing powder based on carbonate and / or chloride and / or phosphate of alkali metals and / or alkaline earth metals and / or based on ammonium or a misting solution of orthophosphoric acid.

The disperse gas mixture is simultaneously supplied from several generators which float on the surface of the liquid in the tank and are located both at the periphery of the tank and at its center. The resulting vector is the horizontal sputtering of the peripheral generators towards the center and the center generators aligned towards the edge. The resulting sputter vector of the top hemisphere facing peripheral generators is oriented toward the center of the flame and the centrally located generators from the center of the burning surface mirror to the edge at an angle of 90 ° to the above vector.

The main deficiency of this process is its explosion instability. That is, in a steam explosion of highly flammable liquids or fuel liquid disassembly of the floating on the liquid surface facilities in the SHT comes about, so that these facilities are thrown out of the tank.

By the patent RU 2355450 C2 is a method for extinguishing highly inflammable and combustible liquids in fixed roof tanks or in solid roof tanks with pontoon or floating tank known. In this case, the disperse fire extinguishing gas mixture is conveyed from a fire extinguishing module device or a group of devices which are arranged outside the tank or on the floating roof of the tank. The method is characterized in that the disperse fire extinguishing gas mixture is produced in two steps. The first step takes place in an antechamber of the container containing the dispersed heterogeneous flame retardant. It is at least one fifth of the gaseous and / or liquefied flame retardant or the mixture of gaseous and / or liquefied phlegmatizer with methyl, ethyl, propylcarbinol or their mixture and / or 5 - 20% of an iodine solution or an iodide of the alkali metal or ammonium or their mixture in the abovementioned carbinol solvents under a pressure of at least 2.5 MPa promoted. The gaseous and / or liquefied mixture ingredients are admitted into the pre-chamber from a bottle or a bottle system or a gas generator with triggering and locking devices according to a signal from a detector or manually via a ventilation pipe. The ventilation pipe is installed inside the prechamber. The antechamber is equipped with an outlet valve a secondary acceleration mixing chamber connected. The release and locking devices open at pressure of at least 0.9 MPa. Here, a final disperse gas mixture of gas to the disperse phase is formed in a ratio in the range of 0.35: 1 to 100: 1. In this case, such a ratio of the gas and liquefied phlegmatizer is taken, which ensures a pressure of at least 4 MPa at a temperature of -50 ° C in the bottled gas system. The second step: The disperse gas mixture is conveyed from the acceleration mixing chamber via a pipeline into a nozzle unit. The nozzle unit has a shut-off valve which opens the nozzle unit. The nozzle unit is provided with a supersonic confuser, wherein the length-diameter ratio of the nozzle a pressure of at least 0.1 MPa at the mouth and a mass consumption of at least 15 kg / sec. ensures. In this case, carbon dioxide and / or fluorocarbons or sulfur hexafluoride are used as the gaseous and / or liquefied phlegmatizer. As gaseous and / or liquefied homogeneous flame retardants bromine and / or iodine-halogenated hydrocarbons are used. The gas phlegmatizers used are nitrogen or argon. As heterogeneous flame retardants, fire-extinguishing powders based on chloride, sulfate, phosphate or carbonate of alkali metals, alkaline earth metals or ammonium or their mixture are used.

By the patent RU 2355450 C2 is a tank extinguishing method for fuel known. The disadvantage of this method is that its application is rather difficult. This is because the spray nozzle is above the surface of the fuel. That is why their decomposition comes about in an explosive combustion.

By the patent RU 2258549 from 03.02.2004 a tank extinguishing procedure is known, which is regarded as a prototype. According to this method, a disperse gas fire extinguishing mixture is supplied to the liquid burning section from a center-floating device.

The disadvantage of the prototype process is also an explosion instability.

The one by the patent US 5573068 (IPC A 62 C3 / 06 of 12.11.1996) known fuel oil fire fighting equipment comprises a gas-powder injector and / or a gas-liquid injector (foam generator - foam generator), which the fire extinguishing agent in a system of annular and radial pipes via a trigger shut-off device. The pipes are horizontal in oil and flush with the bottom of the tank and are connected to a system of vertical pipes. The upper part of these tubes lies above the surface of the oil. In the upper part of these tubes each spray nozzles are installed, which ensure the supply of fire extinguishing agent over the burning surface of the fuel liquid during the oil fire. This device is considered a prototype.

1. 1. Ein hoher Metallaufwand der Einrichtung, z. B. der Tank SHT-5000 mit einem Ölspiegeldurchmesser von 22,8 m und einer Säulenhöhe von 11,92 m: Gemäß der Beschreibung der Prototypeinrichtung wird die Menge von Ringrohrleitungen als $\text{exception 25:}$$\sqrt[3]{{}_{}}$
   
   festgelegt. Das heißt, in unserem Fall beläuft sich die Anzahl der Ringrohrleitungen auf $\sqrt[3]{228}=2.83$
   
   also 3 Ringrohrleitungen. Dabei steht die Ringrohrleitung mit dem größten Radius weniger als 1 m von der Innenwandung von SHT ab. Das heißt, der max. Ringdurchmesser beträgt ca. 21 m, der mittlere ca. 14 m und der innere Ringdurchmesser ca. 7 m. Alle drei Ringe sind wenigstens mit Hilfe von sechs sich kreuzenden Radialrohren verbunden. Das heißt, es kommen noch 6 Rohre à 21 m hinzu. An den Kreuzungen der Ring- und Radialrohre sind senkrechte, ca. 11 m hohe Ablaufrohre montiert. Das sind noch 13 Rohre à 11 m lang. Somit beträgt die Gesamtlänge der Rohrleitungen: L = πD₁ + πD₂ + πD ₃ + D₁ +13 ·11 m = 66 m + 44 m + 22 m + 126 m +143 m = 401 m. Der Innendurchmesser der Rohrleitung für ein Schaumfeuerlöschen beträgt 200 mm und für ein Pulverlöschen 50 mm. Das Gewicht der Schaum-Stahlrohrleitung für das Pulverlöschsystem bei einer Wandstärke von 5 mm ist 9,6 t. Bei einer Wandstärke von 3 mm beträgt das Rohrleitungsgewicht nur 1,5 t.
2. 2. Die Sprühdüsen sind über dem höchsten Flüssigkeitsstand auf einer Höhe von 0,15 - 0,3 m starr befestigt. Die Säule der Brennflüssigkeit kann in SHT-5000 11,5 m betragen. Das heißt, je nach dem Verbrauch der Brennflüssigkeit oder der leicht entzündbaren Flüssigkeit, die sich im Behälter befinden, werden die Löschbedingungen unterschiedlich sein, weil es viel schwieriger ist, den Strahl auf die brennende Oberfläche mit einer Höhe von 11,5 m zu fördern, sowohl wegen der Bewegungsenergieverluste beim Strahl als auch wegen der Überwindung der Gegenströmung der verdunstbaren Brennflüssigkeit und/oder der Verbrennungsprodukte dieser Flüssigkeit.
3. 3. Bei Ölbränden in SHT mit festem oder schwimmendem Dach kommen praktisch immer eine räumliche Verbrennung der im SHT enthaltenen Dämpfe und in der Regel die Zerlegung des Festdachs und der automatischen Feuerlöschanlagen zustande, die im oberen Teil von SHT eingebaut sind (s. I.F. Sharovarnikov, V.P. Moltchanov und andere. Erdölbrandbekämpfung. - M.: Kalan, 2002, S. 437 ).
4. 4. Ein wesentlicher Nachteil der Prototypeinrichtung ist ebenfalls der hohe spezifische Feuerlöschmittelverbrauch, wenn das Feuerlöschmittel dem Brandbereich von oben zugeführt wird (s. A.N. Baratov, E.M. Ivanov. Feuerlöschen in Chemie- und Petrochemiebetrieben. -M.: Chimia, 1979, S. 368 sowie die vorherige Quelle: I.F. Sharovarnikov, V.P. Moltchanov und andere. Erdölbrandbekämpfung. - M.: Kalan, 2002, S. 437 ). Der Verbrauch des Feuerlöschmittels auf Natronbasis und eines Pulvers auf Ammoniumphosphat-Basis beträgt gemäß den oben genannten Druckschriften 1,5 bis 4,5 kg/m². Bei Schaum beläuft sich der Verbrauch auf 1,4 bis 2,6 kg/m².

The shortcomings of this prototype device are:

1. 1. A high metal cost of the device, eg. For example, the tank SHT-5000 with an oil level diameter of 22.8 m and a column height of 11.92 m: According to the description of the prototype device, the amount of ring piping as $\sqrt[3]{{\mathrm{<figure-callout\; id="3"\; label="d\; tank"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">d\; </figure-callout>}}_{\mathrm{tank}}}$
   
   established. That is, in our case, the number of ring pipes amounts to $\sqrt[3]{228}=2.83$
   
   So 3 ring pipes. Here, the ring pipe with the largest radius is less than 1 m from the inner wall of SHT. That means, the max. Ring diameter is about 21 m, the middle about 14 m and the inner ring diameter about 7 m. All three rings are connected at least with the help of six intersecting radial tubes. In other words, 6 tubes of 21 m each will be added. At the intersections of the ring and radial pipes vertical, about 11 m high drainpipes are mounted. That's 13 more tubes, each 11 meters long. Thus, the total length of the pipelines is: L = π D ₁ + π D ₂ + πD ₃ + D ₁ +13 × 11 m = 66 m + 44 m + 22 m + 126 m +143 m = 401 m. The inner diameter the pipe for a foam fire extinguishing is 200 mm and for a powder extinguishing 50 mm. The weight of the foam steel pipe for the powder extinguishing system with a wall thickness of 5 mm is 9.6 t. With a wall thickness of 3 mm, the pipe weight is only 1.5 t.
2. 2. The spray nozzles are rigidly mounted above the highest liquid level at a height of 0.15 - 0.3 m. The column of the fuel liquid can be 11.5 m in SHT-5000. That is, depending on the consumption of the fuel liquid or the highly flammable liquid that is in the container, the extinguishing conditions will be different, because it is much more difficult to convey the jet to the burning surface with a height of 11.5 m, both because of the kinetic energy losses in the jet and because of the overcoming of the counterflow of the vaporizable fuel liquid and / or the combustion products of this liquid.
3. 3. Oil fires in SHTs with fixed or floating roofs are practically always subject to spatial combustion of the vapors contained in the SHT and, as a rule, the dismantling of the fixed roof and the automatic fire extinguishing systems installed in the upper part of SHT (s. IF Sharovarnikov, VP Moltchanov and others. Oil fire fighting. - M .: Kalan, 2002, p. 437 ).
4. 4. A major disadvantage of the prototype device is also the high specific fire extinguisher consumption when the fire extinguishing agent is supplied to the fire area from above (s. AN Baratov, EM Ivanov. Fire extinguishing in chemical and petrochemical companies. -M .: Chimia, 1979, p. 368 as well as the previous source: IF Sharovarnikov, VP Moltchanov and others. Oil fire fighting. - M .: Kalan, 2002, p. 437 ). The consumption of the sodium-based fire extinguishing agent and an ammonium phosphate-based powder is 1.5 to 4.5 kg / m ² according to the above-mentioned references. With foam amounts Consumption to 1.4 to 2.6 kg / m ² .

By DE 908 940 C is a particular intended for fuel storage containers fire extinguishing device known. The device provides a supply of the extinguishing agent to the container bottom and a discharge of the extinguishing agent on the liquid level in the container. It comprises a buoyancy body connected to a displacement outlet via a entrainable connection line and provided with a displacement outlet, an extinguishing medium line entrained by the latter and connected to the inlet arranged in the bottom of the tank, and outlets for the extinguishing agent carried by the buoyancy body.

It is an object of the invention to provide a method which is resistant to oil spills in the tanks and which ensures effective extinguishment of petroleum fires in tanks by shortening the extinguishing time and reducing the metal expense for the construction of a facility.

The stated object is solved by the features of claim 1.

wobei

• L_R - die Länge der Rohrleitung zwischen dem Injektor und der Schwimmer-Sprühdüse (Leitungslänge vom Eintrittspunkt im Tank bis zur Verbindungsstelle mit der Schwimmer- Sprühdüse) in m,
• R_T - der Tankradius in m,
• H_bF - die max. Einfüllhöhe der brennbaren Flüssigkeit im Tank in m,
• H_Inj - die Eintrittshöhe der Auslassleitung aus dem Injektor in den Tank in m und
• H_Düse - die Höhe der Sprühdüse in m

sind.The object is achieved in the execution of the method and the device for extinguishing the fuel liquid in solid roof tanks. For this purpose, a gas or dispersion gas fire extinguishing mixture from an extinguishing module device (injector) located outside the tank via a triggering shut-off device, an outlet line and a spray nozzle transported in the fire zone. In the process, a float spray nozzle emerges on the surface of the burning liquid for firefighting purposes. The fire extinguishing is carried out in three steps:
First step: The above-mentioned float spray nozzle is placed under the layer of flammable liquid. The installation depth corresponds at least to the height of the spray nozzle and / or the surface of said liquid. The cable length is determined from the following ratio: $${\mathrm{L}}_{\mathrm{R}}=\sqrt{{\mathrm{R}}^2{}_{\mathrm{T}}+{\left({\mathrm{H}}_{\mathrm{bF}}-{\mathrm{H}}_{\mathrm{lnj}}-{\mathrm{<figure-callout\; id="2"\; label="H\; jet"\; filenames="imgf0002.png"\; state="\{\{state\}\}">H\; </figure-callout>}}_{\mathrm{jet}}\right)}^2}$$

in which

• L _R - the length of the pipeline between the injector and the float spray nozzle (line length from the entry point in the tank to the point of connection with the float spray nozzle) in m,
• R _T - the tank radius in m,
• H _bF - the max. Filling height of the combustible liquid in the tank in m,
• H _Inj - the inlet height of the outlet pipe from the injector into the tank in m and
• H _nozzle - the height of the spray nozzle in m

are.

Second step: After a signal from the fire detector, the trigger shut-off device on the injector is opened. The above-mentioned fire extinguishing mixture is supplied from the injector to the exhaust pipe and the float spray nozzle. The fire extinguishing mixture is directed from the float spray nozzle just below the layer and / or on the surface of the liquid in closed jets from the center to the edge. The rays run in the same direction with the mirror and with a deflection of 360 °. 0.05 - 0.2 parts of the above-mentioned fire extinguishing mixture are atomized through the nozzles at an angle of 3 to 90 ° to the surface of the burning liquid in the tank to generate a buoyant force. This buoyancy force ensures the positive buoyancy of the "Outlet Line - Float Spray Nozzle" arrangement.

wobei

• n für die Anzahl der Strahlen und
• α für den Strahl-Divergenzwinkel stehen.

The third step causes the float spray nozzle above the burning surface to rise to a height of 0.005 D _T to 0.05 D _T , where D _{T is} the tank diameter. The fire extinguishing mixture is conveyed at a flow rate of at least 0.15 kg / s · m ² with a circular deflection of the jets. The number of beams is determined as follows: $$\frac{90°}{\mathrm{\alpha }}\le \mathrm{n}\le \frac{360°}{\mathrm{\alpha }}$$

in which

• n for the number of rays and
• α are the beam divergence angle.

The spray nozzle may be arranged in advance over the surface of the layer of the combustible liquid.

As the dispersion gas fire extinguishing mixture, a disperse fire extinguishing composition is used. It contains a highly dispersed additive, a flowability targeting additive, an organosilicon hydrophobing agent, a powdered main flame retardant and a gaseous and / or liquefied phlegmatizer or a mixture of a phlegmatizer and a liquid flame retardant. As gaseous and / or liquefied phlegmatizer here are carbon dioxide or a mixture of carbon dioxide and nitrogen or air in the ratio of 9: 1 to 4: 1 or a mixture of carbon dioxide and alkyl carbinol in the ratio of 99: 1 to 90: 10 or a mixture of Carbon dioxide and nitrogen or air with alkyl carbinol in the ratio 80 - 100: 5 - 20: 0.5 - 5 used. As the liquid flame retardant, a 5% iodine solution or a 5-20% mixed solution of iodine and iodide of an alkali metal or ammonium in alkyl carbinol is used. The ratio in the mixture phlegmatizer: liquid flame retardant in the range of 100: 1 to 100: 30. The carbon dioxide is modified by dimethyl ketone from 100: 1 to 10: 1 and that at the following proportions in wt.% highly dispersed additive - 0.2-2.8; Target additive for flowability - 4,6 - 25; organosilicon hydrophobing agent - 0.1-0.7; powdered main flame retardant - 15-85; Phlegmatizer or mixture of phlegmatizer and liquid flame retardant - Rest.

As a gas fire extinguishing mixture a extinguishing composition with compressed propellant gases (nitrogen, argon, nitrogen extinguishing gas or their mixture with air) and liquefied quenching gases (carbon dioxide, sulfur hexafluoride, halogenated hydrocarbons or their mixture) are used. The compressed gas to liquefied gas ratio in% by weight is as follows: Compressed gases - 6,6 - 60 Liquefied gases - Rest.

wobei

n

- die Anzahl der Diffusoren und

α

- der Winkel des Diffusors sind.

The external device (injector) for extinguishing petroleum fires, flammable and highly flammable liquids in a tank comprises a container with disperse fire extinguishing composition or liquefied gas composition and a vessel with gaseous propellant phlegmatizer or a vessel with combination of the dispersed fire extinguishing composition or gas composition and propellant gas , The propellant ensures the injection of the above fire extinguishing compositions via a triggering and shut-off device, an outlet line with a spray nozzle inwards to the tank in the fire zone. The device is characterized in that the outlet pipe on the outside of the tank via a joint and the triggering and shut-off device is connected to the injector. On the other side, the outlet pipe is connected to a spray nozzle via a joint and a float. The float is designed with controllable buoyancy, which the emergence of the spray nozzle during fire extinguishing and the arrangement ensures the spray nozzle above the burning surface at the height of 0.005 - 0.05 times the tank diameter. The spray nozzle has at least one row of nozzle holes, which lie in a horizontal plane with a deflection of 360 °. The nozzle holes of the spray nozzle are in the form of diffusers. Of these, 80 - 95% are in the horizontal plane and 5 to 20% oblique - at an angle of 3 to 90 ° - to this plane. The total amount of diffuser nozzles is selected from the following ratio: $$\frac{90°}{\underset{\_}{\mathrm{\alpha }}}\le \mathrm{n}\le \frac{360°}{\mathrm{\alpha }}$$

in which

n

- the number of diffusers and

α

- the angle of the diffuser is.

The triggering and shut-off device is designed with an electrical and / or a compressed air and / or a manual release in conventional or explosion-proof design.

Physical focus of the invention:

1. 1. Flüssiger Treibstoff brennt immer in einer Dampfphase.
2. 2. Die Wärme, die von der Flamme an die Oberfläche der Flüssigkeit hingeleitet wird, wird dafür verbraucht, die Flüssigkeit in der Grenzschicht zu erwärmen, sie zu verdunsten und die Dämpfe aufzuwärmen.
3. 3. Für die Praxis kann angenommen werden, dass die Oberflächentemperatur der brennenden Flüssigkeit mit dem Siedepunkt dieser Flüssigkeit zusammenfällt.
4. 4. Es gibt einen sehr beachtlichen Zusammenhang zwischen dem Sattdampfdruck von Erdöl und Ölprodukten und der Temperatur. Eine geringe Senkung der Oberflächentemperatur der brennbaren Flüssigkeit ergibt eine wesentliche Abnahme des Sattdampfdrucks.
5. 5. Die Hauptwärmeentwicklung kommt bei der Verbrennung der brennbaren Flüssigkeit im leuchtenden Bereich (der Flamme) zustande.
6. 6. Die Erwärmung der Flüssigkeit wird dank der Strahlungswärme erreicht, welche aus den oberen Flammenschichten kommt; dabei ist die Strahlungsstärke gemäß Stephan-Bolzmann-Gesetz der Temperatur in der vierten Potenz direkt proportional: I_Flamm ≈ σT⁴ W/sr.

In the publication of VV Pomerantsev, KM Arefyev, DB Akhmedov and other "Foundations of the combustion theory". Handbook for University Students. L., ENERGY, 1973, p. 262 , the following is asserted:

1. 1. Liquid fuel always burns in a vapor phase.
2. 2. The heat that is transferred from the flame to the surface of the liquid is used to heat the liquid in the boundary layer, to evaporate it and to warm the vapors.
3. 3. In practice it can be assumed that the surface temperature of the burning liquid coincides with the boiling point of this liquid.
4. 4. There is a very remarkable relationship between the saturated steam pressure of petroleum and oil products and the temperature. A small decrease in the surface temperature of the combustible liquid results in a substantial decrease in saturated steam pressure.
5. 5. The main heat development occurs when burning the combustible liquid in the luminous area (the flame).
6. 6. The heating of the liquid is achieved thanks to the radiant heat coming from the upper layers of flames; In this case, the radiation intensity according to Stephan-Bolzmann's law is directly proportional to the temperature in the fourth power: I _Flame ≈ σT ⁴ W / sr.

1. 1. Senkung der Oberflächentemperatur der brennenden Flüssigkeit,
2. 2. Erdöldampfdruckabbau,
3. 3. Absperren (Verminderung) der Wärmeabgabe aus dem Brennbereich (Flamme) in den erwärmten Bereich.

From the above, it is clear that the effective combustion of oil and petroleum products requires the following actions:

1. 1. lowering the surface temperature of the burning liquid,
2. 2. petroleum vapor pressure reduction,
3. 3. Shutting off (reducing) the heat output from the burning area (flame) into the heated area.

All of these measures are ensured in the application of the extinguishing method according to the invention using the device described above.

1. 1. Die gekühlte Dispersionsgas-Mischung (flüssiges CO₂ + Löschpulver) wird in die Grenzschicht und/oder unter die Grenzschicht der Flüssigkeit befördert. Das vermindert beachtlich die Temperatur der erwärmten Schicht.
2. 2. Die Wärmestrahlung von der Flamme zur Erdöloberfläche hin wird dadurch vermindert, dass eine Aerosol-"Wolke" zwischen der Grenzschicht der Flüssigkeit und dem Leuchtbereich der Flamme gebildet wird. Die Abschwächung der Strahlung unterliegt dem Bouguer-Lambert-Beerschen Gesetz: $${\mathrm{\Phi }}_{\mathrm{pass}}={\mathrm{\Phi }}_0\cdot {\mathrm{e}}^{-\mathrm{\epsilon }\cdot \mathrm{c}\cdot \mathrm{l}}.$$
   

worin

Φ_bass

- der Wärmestrom, der die Aerosolschicht passiert hat in W/sr,

Φ₀

- der Wärmestrom, der von der Flamme gestrahlt wird in W/sr,

e

- die Basis der natürlichen Logarithmen,

ε

- die Extinktionskonstante in m²/g,

c

- die Aerosolkonzentration in der Schicht in g/m³,

l

- die Stärke der Aerosolschicht in m

bedeuten.In fact:

1. 1. The cooled dispersion gas mixture (liquid CO ₂ + extinguishing powder) is conveyed into the boundary layer and / or under the boundary layer of the liquid. This considerably reduces the temperature of the heated layer.
2. 2. The heat radiation from the flame to the surface of the oil is reduced by forming an aerosol "cloud" between the boundary layer of the liquid and the luminous area of the flame. The attenuation of radiation is governed by Bouguer-Lambert-Beer's law: $${\mathrm{\Phi }}_{\mathrm{passport}}={\mathrm{\Phi }}_0\cdot {\mathrm{e}}^{-\mathrm{\epsilon }\cdot \mathrm{c}\cdot \mathrm{l}},$$
   

wherein

Φ _bass

the heat flow which has passed through the aerosol layer in W / sr,

Φ ₀

the heat flow radiated from the flame in W / sr,

e

- the base of natural logarithms,

ε

the extinction constant in m ² / g,

c

the aerosol concentration in the layer in g / m ³ ,

l

the strength of the aerosol layer in m

mean.

betragen.As an example, the multiple of the thermal radiation reduction in the range of 0.8 - 14 microns in the spectrum of electromagnetic radiation during fire in the SHT-5000 in the case of application of the aerosol protection method (AS) calculated. The diameter of the SHT-5000 is 21.1 m. The surface of the oil level is 356 m ² . According to the procedure, 6 modules with extinguishing powder MPP "BiZone-100" (2 pieces per foam discharge KNP-5) are placed around SHT. The total amount of phosphate powder is 480 kg. The flow time of the dispersion gas mixture from the modules is approx. 6 seconds. It can therefore be calculated that the entire SHT area (S = 356 m ² ) per 1 second is completely covered with a 1 m thick layer. Thus the powder concentration in the aerosol curtain becomes $${\mathrm{C}}_{\mathrm{AS}}=\left(480:6\right)\mathrm{kg}/\left(356{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="imgf0002.png"\; state="\{\{state\}\}">m</figure-callout>}}^2\cdot 1m\right)=0.22\mathrm{kg}/{\mathrm{<figure-callout\; id="3"\; label="m"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">m</figure-callout>}}^3=220G/{\mathrm{<figure-callout\; id="3"\; label="m"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">m</figure-callout>}}^3$$

be.

The extinction _constant ε _0.8-14 in the IR range (0.8-14) μm for monoammonium phosphate powder is about 0.05 to 0.1 m ² / g, depending on its degree of dispersity.

In this example, an average of the extinction _constant ε _0.8-14 = 0.075 m ² / g is taken.

wobei

• ε_0,8-14 - die Extinktionskonstante der elektromagnetischen Strahlung (EMS) im Bereich von 0,8 - 14 µm in m²/g,
• c - die Volumen-Massenkonzentration von Aerosol in g/m³,
• l - die Stärke des Aerosolschleiers innerhalb der Zielstrecke in m sind.

After the transformation of (1) the following results: $$\mathrm{K}={\mathrm{\Phi }}_0/\mathrm{\Phi }={\mathrm{e}}^{\mathrm{\epsilon cl}}.$$

in which

• ε _0.8-14 - the extinction _{constant of} the electromagnetic radiation (EMS) in the range of 0.8 - 14 μm in m ² / g,
• c - the volume mass concentration of aerosol in g / m ³ ,
• l - the strength of the aerosol curtain within the target distance in m.

das heißt, die Flammenstrahlung wird praktisch völlig abgeschirmt.After inserting the above values in (2) you get $$\mathrm{K}={\mathrm{\Phi }}_0/\mathrm{\Phi }={\mathrm{e}}^{\mathrm{0,075}\cdot 220\cdot 1}=1.46\cdot {10}^7.$$

that is, the flame radiation is virtually completely shielded.

Implementation of the invention

The blending of the powdery ingredients and the preparation of the dry powdered flame retardant are carried out in a plant and by a method that are common in the production of extinguishing powders. The prepared dry flame retardant is filled into the powder container (bottle) with the aid of a filling system (eg PSM plant). The phlegmatizing propellant, the liquefied flame retardant and the modifier of the liquefied phlegmatizer are filled into the gas container of the device by means of the filling system (3CA). This gas container will subsequently serve as a gas source.

During application of the device, the dispersion and gas components are mixed together. This results in the dispersion gas fire extinguishing mixture which is sprayed into the firing range according to the invention.

Tables 1 to 3 contain exemplary compositions for filling the devices according to the invention as well as the test results achieved in petroleum firefighting with the aid of the method according to the invention and the respective device on the model firing range 233B.

The procedure is carried out as follows:

The dispersion gas fire extinguisher module ("BiZone-100" type) is placed outside the SHT or SHTPK or SHTP near the inlet of the tank. The "BiZone-100" (the injector) is connected to the float spray nozzle via the trigger and shut-off device by means of a flexible (articulated or other) or fixed pipe. The float spray nozzle is placed under the layer of flammable liquid in the tank or on the surface of said liquid according to claim 1 of the invention. After the signal from the detector, the tripping and shut-off device is opened. The fire fighting takes place via the outlet pipe and the spray nozzle in two steps. First, the fire extinguishing agent is placed under the layer and / or on the surface of the combustible liquid and then above the surface of the fuel liquid at a level of 0.005D to 0.05D (D stands for SHT diameter).

Fig. 1

die Einrichtung zum Löschen von Erdölbränden in SHT mit Festdach ohne Ponton im Bereitschaftszustand,

Fig. 2

die gleiche Einrichtung im Arbeitszustand (während der Brandbekämpfung),

Fig. 3

die Einrichtung zum Löschen von Erdölbränden in SHT mit Festdach mit Ponton im Bereitschaftszustand,

Fig. 4

die gleiche Einrichtung nach Fig. 3 im Arbeitszustand,

Fig. 5

die Kreissprühdüse mit einem Schwimmer,

Fig. 6

die Außenansicht der Gelenkverbindung und

Fig. 7

die schematische Darstellung des Gelenks.

The invention will be explained in more detail with reference to the drawings. Show it:

Fig. 1

the device for extinguishing petroleum fires in SHT with fixed roof without pontoon in the ready state,

Fig. 2

the same equipment in working condition (during firefighting),

Fig. 3

the device for extinguishing petroleum fires in SHT with fixed roof with pontoon in standby mode,

Fig. 4

the same device after Fig. 3 in working condition,

Fig. 5

the circular spray nozzle with a float,

Fig. 6

the exterior view of the articulated joint and

Fig. 7

the schematic representation of the joint.

1

Injektormodul für Dispersionsgas-Mischung

2

Auslöse- und Absperrvorrichtung

3

Gelenke

4

Gehäuse von SHT

5

Auslassleitung

6

Schicht von Erdöl oder Erdölprodukte

7

Kreissprühdüse

8

Schwimmer der Sprühdüse

9

Festdach

10

Schwimmerponton

11

Pontonschwimmer.

Fig. 1, 2 . 3, 4 are provided with reference numerals. Show it:

1

Injector module for dispersion gas mixture

2

Tripping and shut-off device

3

joints

4

Housing by SHT

5

outlet pipe

6

Layer of petroleum or petroleum products

7

Kreissprühdüse

8th

Float of the spray nozzle

9

fixed roof

10

float pontoon

11

Pontoon floats.

The best embodiment of the invention

The device for extinguishing crude oil and petroleum products 6 in steel roofed tanks (SHT) with fixed roof 9 and in SHT with pontoon 10 (SHTP) works according to the method according to the invention as follows:
When a fire occurs, a signal from the fire detector comes into the monitoring triggering device of the fire extinguishing system. From here, the signal comes as an electric or compressed air signal in the triggering and shut-off device 2, which is located on the bottle with phlegmatizing propellant gas injector 1. Then the phlegmatizing gas enters the container with the dispersed chemical flame retardant. As it flows through the container, it forms the disperse fire extinguishing gas mixture, the recipe of which is given in Tables 1-3. This fire extinguishing gas mixture comes via the outlet 5 and the articulated connections 3 in the Kreissprühdüse 7. From here, the dispersion gas mixture flows under the layer 6 of petroleum and petroleum products. Below the layer 6, the dispersion gas mixture spreads in the same direction and cools it. As a result, this layer 6 is phlegmatized. A portion (5 to 20%) of the dispersion gas mixture which flows out of the circular spray nozzle 7 at a flow rate of at least 0.15 kg / s · m ² produces the positive buoyancy for the float 8 Console "Kreissprühdüse - joint outlet pipe" and finally the emergence of the Kreissprühdüse 7 ensured. The circular spray nozzle 7 delivers the disperse fire extinguishing gas mixture to the burning surface of the layer 6 or below the float pontoon 10 with the pontoon floats 11.

In addition, the pre-assembly of the Kreissprühdüse 7 over the surface of the combustible liquid layer 6 is permissible.

Industrial Applicability

• in Bezug auf die effektive Löschzeit: 1,3- bis 50fach;
• in Bezug auf die Verringerung des spezifischen Metallaufwands
  der Konstruktion: 1,1- bis 14fach.

From the information given above, as well as from the test results according to Tables 1-3, it can be seen that the method and the device according to the invention are advantageous over the prototype method and the prototype device, namely:

• in terms of effective extinguishing time: 1.3 to 50 times;
• in terms of reducing the specific metal cost
  Construction: 1.1 to 14 times.

Tabelle 3 Zutaten Prototyp Zutatenanteil (% Gew.) Verfahren Einrichtung Ausgestaltungen der Erfindung RU 2258549 US 5573068 379 380 381 382 383 1 2 3 4 5 6 7 1. Hochdisperser Zusatz (Siliziumoxid) 0,2-2,8 - - - - - 2. Zielzusatz für Fließbarkeit 4,6-25 - - - - - 3. Siliziumorganisches Hydrophobiermittel 0,1-0,7 - - - - - 4. Pulverförmiger Hauptflammenhemmer 15-85 - - - - - 5. Mischung von Kohlendioxid, Stickstoff und Halogenkohlenwasserstoff Rest bis zu 100% - - - - - 6. Druckgas - Luft - 6,5 6,6 30 60 61 7. Verflüssigtes Gas - Kohlendioxid - 93,5 95,4 70 40 39 8. Löschzeit bei Durchflussrate der Mischung l=0,15kg/Sek·m², Sek. 1,5-20 2-3,5 0,9-1,45 0,7-1,3 0,8-1,4 2,5-20 9. Spezifischer Metallaufwand pro 1m² der Schutzfläche, kg/m² 0,47-4,34 0,31-0,42 0,31-0,42 0,31-0,42 0,31-0,42 0,31-0,42 10. Beständigkeit gegen Explosion von Brenn- und leicht entzündbaren Flüssigkeiten, Ja (+), Nein (-) - + + + + + In this case, the method and the device according to the invention provide the new positive property, namely the resistance to the explosion of the petroleum vapor and the flammable and highly flammable liquids.

Table 3 ingredients prototype Ingredient content (% by weight) method Facility Embodiments of the invention RU 2258549 US 5573068 379 380 381 382 383 1 2 3 4 5 6 7 1. High dispersion additive (silica) 0.2-2.8 - - - - - 2. Target additive for flowability 4.6 to 25 - - - - - 3. Organosilicon hydrophobing agent 0.1-0.7 - - - - - 4. Powdery main flame retardant 15-85 - - - - - 5. Mixture of carbon dioxide, nitrogen and halohydrocarbon Remainder up to 100% - - - - - 6. compressed gas - air - 6.5 6.6 30 60 61 7. Liquefied gas - carbon dioxide - 93.5 95.4 70 40 39 8. Extinguishing time at flow rate of the mixture l = 0.15kg / sec · m ² , sec. 1.5-20 2-3.5 0.9 to 1.45 0.7-1.3 0.8-1.4 2.5-20 9. Specific metal expenditure per 1m ^{2 of} the protection area, kg / m ² 0.47 to 4.34 0.31 to 0.42 0.31 to 0.42 0.31 to 0.42 0.31 to 0.42 0.31 to 0.42 10. Resistance to explosion of flammable and highly flammable liquids, Yes (+), No (-) - + + + + +

Claims (2)

1. A method for extinguishing tank fires for extinguishing petroleum fires, in which a gas or dispersion gas fire extinguishing mixture is fed into the fire zone from in internal fire extinguishing device (injector) via a tripping and shutoff device (2), a discharge line (5), and a circular spray nozzle (7),
   characterized in that
   said fire extinguishing mixture is supplied from a float-type circular spray nozzle (7) that pops up above the surface of the burning liquid, and the fire extinguishing is performed in three steps:

   1st step: the float-type circular spray nozzle (7), communicating with the injector (1) by means of a pipeline via the tripping and shutoff device (2) is located below the layer (6) of the flammable liquid at a depth equivalent to at least the height of the circular spray nozzle (7) and/or is located on the surface of said liquid, and the length of the pipeline is defined by the following ratio: $${\mathrm{L}}_{\mathrm{R}}=\sqrt{{\mathrm{R}}^2{}_{\mathrm{T}}+{\left({\mathrm{H}}_{\mathrm{bF}}-{\mathrm{H}}_{\mathrm{lnj}}-{\mathrm{H}}_{\mathrm{Düse}}\right)}^2}$$

   

   wherein

   L_R is the length of the pipeline in meters,

   R_T is the tank radius in meters,

   H_bF is the maximum fill height of the flammable liquid in the tank in meters,

   H_Inj is the entry height of the discharge line (3) from the injector (1) into the tank in meters,
   and

   H_Düse is the height of the circular spray nozzle (7) in meters;

   2nd step: after a signal from the fire alarm, the tripping and shutoff device (2) is opened at the injector (1), and said fire extinguishing mixture is fed via the pipeline and the float-type circular spray nozzle (7) beneath the layer (6) and/or onto the sur face of the flammable fluid in closed streams from the center point to the edge parallel to the surface, specifically with a deflection of 360 degrees; in the process, 0.05-0.2 parts of said fire extinguishing mixture is atomized at an angle of 3 to 90° to the surface of the liquid;

   3rd step: it is ensured that the float-type circular spray nozzle (7) pops up above the burning surface by a height of 0.005 D_T to 0.05 D_T (where D_T stands for the tank diameter); in the process, the fire extinguishing mixture is fed at a flow rate of at least 0.15 kg/sec·m² with a circular deflection of the streams, and the number of streams is determined as follows: $$\frac{90°}{\mathrm{\alpha }}\le \mathrm{n}\le \frac{360°}{\mathrm{\alpha }}$$

   

   in which

   n stands for the number of streams and

   α stands for the stream divergence angle.
2. The method of claim 1,
   characterized in that
   as the dispersion gas fire extinguishing mixture, a disperse fire extinguishing composition is employed, which has the following ingredients: a highly dispersed additive, a target additive for flowability, silicon-organic hydrophobing agent, a powdered primary flame retardant, and a gaseous and/or liquefied calming agent, or a mixture of calming agent and the liquid flame retardant;
   that as the gaseous and/or liquefied calming agent, carbon dioxide or a mixture of carbon dioxide and nitrogen or air is used in a ratio of 9:1 to 4:1 or a mixture of carbon dioxide with alkylmethanol in a ratio of 99:1 to 90:10, or a mixture of carbon dioxide and nitrogen or air with alkylmethanol in a ratio of 80-100:5-20:0.5-5;
   that as the liquid flame retardant a 5% iodine solution or 5-20% mixture of iodine and iodide of an alkali metal or ammonium in alkylmethanol is used, and in the mixture the ratio of calming agent to liquid flame retardant is in the range from 100:1 to 100:30; and the carbon dioxide is modified by dimethylketone from 100:1 to 10:1, specifically with the following quantitative ratios in weight percent: highly dispersed additive 0.2-2.8 target additive for flowability 4.6-25 silicon organic hydrophobing agent 0.1-0.7 powdered primary flame retardant 15-85 calming agent or mixture of calming agent and liquid flame retardant remainder; and
   that as the gas fire extinguishing mixture, an extinguishing composition with propellant compressed gases (nitrogen, argon, nitrogen extinguishing gas, or mixtures thereof with air) and liquefied extinguishing gases (carbon dioxide, sulfur hexafluoride, halogenated hydrocarbons, or mixtures thereof) is used in the following ratio of compressed gas to liquid gas in weight percent: compressed gases 6.6-60 liquid gases remainder.

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