RU2036186C1 - Method and apparatus to form refractory cover on lining working surface - Google Patents

Abstract

FIELD: metallurgy. SUBSTANCE: stream of refractory and oxidizing materials particles in carrying gas is mixed with stream of oxygen by drawing stream of refractory and oxidizing materials of carrying gas with pressure of 0.345 1.04 in stream of oxygen with pressure of 0.345 1.04 MPa with volumetric ratio of oxygen and carrying gas as (50 30) 1. In the case, at least one of components of following group is used as refractory material: chrome oxide, zirconium oxide, silicon oxide, magnesium oxide, aluminum oxide, silicon carbide, ferric oxide; and at least one of components of following group is used as oxidizing material: chrome, zirconium, silicon, magnesium, aluminum. Apparatus for method realization has bunker with refractory material, pipeline for mixture of refractory particles and carrying gas nozzle for oxygen feeding and sprayer. Sprayer has sucking apparatus with narrowing. Nozzle to feed oxygen is located on common axis with narrowing and pipeline for mixture of refractory particles and carrying gas is located perpendicularly to it. In the case, sucking apparatus is located on inlet end of sprayer or inside it. EFFECT: method and apparatus are used in metallurgy.

Description

 The invention relates to the repair of worn or damaged refractory lining, and in particular to a method and device for the formation and flame spraying of refractory materials containing particles of chromium, aluminum and / or magnesium oxides for repair at the place of such a lining.

 Metal processing furnaces, ladles, combustion chambers, languid wells and similar devices are lined with refractory masonry or coating. Such a lining erodes or is damaged due to stresses arising during operation at high temperatures. The aim of the operators was to repair such dryers or stoves in place while they were hot. Such on-site repairs eliminate the need for cooling and heating periods, as well as severe thermal damage due to excessive temperature changes.

 In the industry, flame spraying technology is well known. Using this technology, molten or sintered refractory particles are sprayed from the spear into the furnace to be repaired. Such a spear may be wrapped with a fibrous protective blanket or may be provided with a water-cooled outer jacket in order to protect it from high temperature during the spraying operation.

 In known flame spraying technologies, dusty coke, kerosene or propane gas was used as fuel, which was mixed with refractory powders or oxides and applied to the wall being repaired.

 British Patent No. 1151423 describes the incorporation of powdered refractory into a fuel gas stream; British Patent No. 992046 describes the incorporation of powdered refractory material into an oxygen stream and the use of propane as fuel.

In US patent N 271822, powdered metals are used as heat sources. In these processes, the formation of shaped masses of refractory is allowed during the oxidation of one or more oxidizable substances, for example aluminum, silicon and / or magnesium, in the presence of refractory oxides such as Al ₂ O ₃ , MgO or SiO ₂ . In these processes, finely ground oxidizable metal powders having a size below about 50-100 microns are used. Such a size of the oxidizable metal promotes rapid oxidation and heat generation in order to melt or soften the introduced refractory particles, as well as soften the repaired area. However, these processes are dangerous due to reverse flashing of the flame. During flameback, the reaction may move back to the spear carrying the machine sleeve or to the operator and may cause damage as well as interruption of the repair. Flashing back is a major disadvantage of the flame spray method.

 A known method (UK patent N 2035524), in which air or other inert gas is used as a carrier gas to transfer refractory refractory and oxidizable substances to the outlet of the spear, where they are mixed with oxygen, which is supplied separately to the outlet of the spear. Despite overcoming some of the dangers of flame spraying of refractory and oxidizable powders, this method shows extremely low coating rates. The low speed of the coating is due to the small amount of the mixture, which is carried by an inert gas, about 0.5 kg per 50-100 l / min. The large amount of oxidizing agent needed to overcome this proportion increases the cost of the process and creates additional hazards that occur when materials are mixed together. So, the examples show the use of 40% metal oxidizing agents in the form of N 100 V mesh (approximately 150 μm). This method also consumes very large volumes of oxygen to compensate for the use of an inert gas as a carrier in a ratio of about (2-4): 1.

The flame spraying of refractory oxides of aluminum, silicon and / or magnesium is well known in the industry. When silicon and aluminum / magnesium are used as fuel, residual silicon oxide (SiO ₂ ) is formed together with these refractory oxides, as a result of which the deposited refractory masses are unsatisfactory in terms of refractoriness to resist wear and tear under highly erosive conditions. Oxidized and refractory powders, which produce more wear-resistant refractory masses, such as chromium fuel for applying residual chromium oxide and zirconium fuel for applying zirconium oxide, have a high reactivity and therefore cannot be used in flame spraying methods due to reverse flashing of the flame and similar phenomena.

 The proposed method and device for flame spraying of refractory and oxidizable powders provides significantly higher deposition rates than previously achieved, while simultaneously allowing the use of oxidizable and refractory powders that are currently considered reactive and prone to flashing back and causing large explosions strength.

 The method and device for the flame spraying of refractory material will allow for on-site repairs of, for example, furnace linings. An inert carrier gas is not capable of supporting combustion and delivers particles of refractory oxide and oxidizable metal or oxidizable material to a flame spray device, where oxygen is sucked in at high pressure and the gas-particle mixture is accelerated. The adjustable ratio of the carrier gas to oxygen allows the use of metal particles with a high flammability, for example chromium, zirconium, aluminum and / or magnesium, as heat sources without flame backsliding. The method and device allows at a rate of deposition of refractory oxide in excess of 907.2 kg / h, to achieve high quality refractory mass having increased wear and erosion resistance.

 The proposed method uses chromium, magnesium, zirconium and other highly reactive oxidizable materials and mixtures that give the best chemical, refractory, with a higher melting point characteristics of the resulting deposited refractory mass compared to silicon and other low melting materials.

 The proposed device absorbs and accelerates the loaded particles to provide a higher density and lower porosity of the applied refractory mass, improving its wear characteristics.

 The method and device of the invention significantly increase the rate of attachment of the applied refractory mass compared to previously known methods and devices, while reducing the rate of application.

 In the method of forming a refractory mass, when a mixture of a carrier gas and charged particles from an oxidizable material and a non-combustible material is sucked into the flame spray device using a high pressure oxygen stream to form an oxygen carrier gas stream, the oxidizable material is refractory.

 The term carrier gas or inert gas means a gas that is unable to support the oxidation of oxidizable elements and includes air as well as inert gases such as argon.

 Suction is carried out by providing an oxygen to carrier gas ratio of (5-30): 1 or more, preferably (8-12): 1. The ratio of oxygen to carrier gas is carried out at such relative pressures as to accelerate the sucked particles.

 The oxidizable material is chromium or aluminum, or magnesium, or zirconium, or mixtures thereof. The refractory material is the oxides of chromium or aluminum, or magnesium, or iron in both oxidized states, as well as zirconium or carbon. Particles of oxidizable material are contained in the mixture in an amount of about 5-20, preferably 8-14, more preferably 8-12 wt.

 The refractory material may be silicon carbide; in this case, the oxidizable material may be silicon, aluminum, chromium, zirconium or magnesium and mixtures thereof and have in a mixture of 10-30 particles, preferably 15-25 wt. In all cases, the oxidizable material has an average grain size of less than about 60, preferably less than about 20 microns.

 A device for forming a refractory mass, comprising a high pressure oxygen stream device for suctioning into a flame spray device a mixture containing a carrier gas and charged particles of an oxidizable material and a non-combustible refractory material to form an oxygen carrier gas stream, an oxidizable material. The suction spray device can be located anywhere in the flame spray device, up to its outlet. The spear can be insulated or protected by a temperature water jacket. The device may include a device for forming a mixture of carrier gas and charged particles, for example, an air inlet or other inert gas in fluid connection with a particle inlet, for example, with a screw feed or a gravity feed. The device for forming the mixture may be an impeller driven by a motor into which air or an inert gas is introduced.

 In FIG. 1 and 2 show a cross section of two embodiments of a flame spray device; in FIG. 3 is a cross-sectional view of a screw feeder acting by gravity and driven by an impeller motor; in FIG. 4 -6 embodiments of the spray device.

 In FIG. 1 shows a flame spray lance 1 having an outlet end 2, a housing 3 surrounded by insulation 4, and an inlet end 5. The inlet end 5 of the lance 1 is equipped with a suction device 6 having a restriction 7, where high pressure oxygen from the source passes through the suction nozzle 8 mixtures of carrier gas and charged particles from conduit 9 through conduit 10.

 In FIG. 2 shows another device for suctioning and accelerating a mixture of carrier gas and particles, where the nozzle 8 delivers high pressure oxygen from the source to the midpoint, and the pipe 10 enters the suction device 6.

 In FIG. 3 shows a flame spray lance 1 similar to that of FIG. 2, except that instead of the suction device 6 located outside the casing, the restriction 7 is located in the casing 3 of the flame spray lance 1 and all lance 1 and conduit 10 are coated with insulation 4. Oxygen is supplied through the nozzle 8 to the midpoint where conduit 10 enters into the housing 3 for suction and acceleration of the mixture.

 FIG. 4-6 illustrate various atomization devices by which carrier gas and particles are mixed to form a stream to be sucked by a flame atomization device.

 The spray device 11 has a hopper 12 containing particles of oxidizable material and refractory material. The hopper 12 is discharged by a screw feeder 13 into a funnel 14 with movable connections to a suction device 15 having a downstream narrowing 16, in which the carrier gas stream from the source is directed through the nozzle 17. The venturi is smoothly connected to the pipe 9 for supplying the carrier gas stream and loaded particles to the lance 1 (Fig. 3).

 In FIG. 5 shows a spray device 11 having a hopper 12, discharged into a suction device 15, smoothly connected to the restriction 16. The discharge can be enhanced by providing external air pressure to the contents of the hopper 12. The carrier gas from the source entering through the nozzle 17 sucks particles to form a flow passing through the narrowing 16 in the pipe 9 for feeding in this way to the fiery spray lance 1.

 Instead of a venturi, the atomizing device 11 may have an engine-driven impeller 18 (FIG. 6) for driving particles to which an appropriate amount of carrier gas is added to form a stream of charged particles for supply through a conduit 9 to the flame atomizing device.

 The use of a suction device at the inlet end of the spear or anywhere along the length of the spear facilitates the introduction of a sufficient amount of oxygen as an accelerator to optimize the material entry rate oxygen carrier gas oxidizable material refractory material at the outlet end of the spear.

 The introduction of an inert carrier gas, such as air, into the particle stream from the spraying machine creates a sufficient dilution effect so as to suppress the flame backturning reaction after the addition of oxygen. Monitoring the carrier gas to oxygen ratio eliminates or makes any flameback that can occur in the lance safe or eliminates or minimizes tip reactions that occur at the outlet end. Tip reactions can cause an increase in refractory mass at the outlet end or along the length of the spear and require interruption of the process to clean or replace the spear, causing a delay.

 It is important that the degree of dilution of oxygen to the carrier gas was in the range (5-10 = 1. Using a suction device at the inlet end of the spear or along its length to the outlet provides flexibility for application rates from 0.45 to 22.7 kg / min. Application rates of 45.4 kg / min can be achieved using proportionally larger mines and higher oxygen rates together with higher carrier gas / particle rates.

The dilution effect with an inert carrier allows one or more highly active oxidizable materials, such as chromium, aluminum, zirconium and / or magnesium, to be used in the process without encountering problems of flame retreat. This effect allows the use in the method of pre-fused powder / grain containing up to 15% iron oxides (FeO, Fe ₂ O ₃ , Fe ₃ O ₄ or rust) in the composition, which, as you know, can cause explosions when mixed with pure oxygen, without encountering problems of flashing back flashes or explosions. Adjusting the mixture (carrier gas) according to the parameters set here allows the use of other highly active materials, for example finely ground metal zirconium powder or materials containing up to 80% iron oxides.

 The use of finely ground oxidizable powders in an amount of 8-12% is enough to create a high-quality refractory mass, with regard to the chemical properties of density and porosity when using this method to create refractory matrices, magnesium oxide (chromium oxide), aluminum oxide. Such powders preferably contain one or more metallic chromium, aluminum, zirconium and / or magnesium; these powders produce bound matrices magnesium oxide / chromite, aluminum oxide / chromite, magnesite / aluminum oxide and zirconia / chromite and / or combinations thereof. Such bonded matrices have increased wear resistance at elevated temperatures compared with bonds such as silicon oxide, obtained using less reactive silicon powder, used in the known technical solution as part or all of the oxidizable material.

 Silicon powder can be used to add in a controlled percentage of silicon oxide in the final chemical analysis, thus allowing a full range of control of the final chemical analyzes. Such additives significantly increase the total percentage of oxidizable powders, since silicon provides a relatively low heat of reaction than more reactive oxidizable powders, such as aluminum or chromium, or magnesium, or zirconium. A typical replacement is 2% silicon for every percent of another powder. Such a substitution will obviously add silicon oxide to the final analysis of the refractory mass. The use of finely ground oxidizable powders for the mixture in an amount of 15-20% is sufficient to create a high-quality refractory mass, as for the chemical properties of density and porosity when using this method to create refractories based on silicon carbide.

 The preferred particle size of the oxidizable materials should be less than about 60 microns, more preferably the particle size should be less than 40 microns, most preferably the particle size should be less than about 20 microns. Smaller particle sizes increase the reaction rate and heat generation to form stronger bonded, deposited refractory masses.

 Very fine particles of oxidizable material are essentially consumed in an exothermic reaction that occurs when the flow of material: oxygen, gas, gas, oxidizable material, refractory material leaves the spear. Any remainder of the stream is here in the form of an oxide of substances or in the form of threads obtained by the chemical compound of various formed oxides. Coarser oxidizable particles are more likely to form an oxide than to be completely consumed in the heat of reaction. However, this is an expensive method of producing oxide, and very fine oxidizing particles are preferred to obtain the desired chemical composition using a specific additive of the corresponding refractory oxide.

 The use of chromium oxide as part of the chemical composition of refractory masses used under high temperature conditions has long been known as a valuable additive to reduce thermal shock or a tendency to stop and improve erosion and wear resistance characteristics. Chromium oxide is found naturally in various parts of the world, although it is subjected to heat treatment in various ways, for example by melting, it contains similar products that are difficult or expensive to remove. One particular source contains most of the iron oxide as an impurity. It is known that this material is capable of imparting particularly good wear resistance characteristics to refractory masses in certain applications.

Another material is produced by crushing defective granular bricks, such as Cohart, for example, some of which are commercially known (Cohart REG or Cohart 104 Grades). Some of these materials typically contain 18-22% Cr ₂ O ₃ and 6-13% iron oxide. When using these materials in the presence of pure oxygen, a strong reverse flashing occurs. However, prior to dilution with an inert carrier and before the addition of oxygen, reverse flashing is eliminated or reduced to a safe or mild level.

 The ratio of carrier gas to oxygen has a strong effect on the ability to form the right conditions for an exothermic reaction. Too much air drowns or cools the reactor, creating high porosity in the formed mass and contributing to a decrease in the wear resistance of the mass. In addition, the percentage of bounce increases significantly and, consequently, the cost of the mass increases. This can make it difficult to maintain an exothermic reaction. A spraying machine moving particles using air as a suction agent most preferably operates at 0.035-0.104 MPa of air, moving particles to a flame spraying device when using oxygen as a suction agent, preferably at 0.35-1.04 MPa of oxygen. In this case, the same size of the nozzles for air and oxygen gives the average most preferred degree of volumetric dilution of oxygen to air 10: 1. Low (5: 1) and high (30: 1) dilutions of oxygen to air can be effective, although at 30: 1 the flame can sometimes slip back with highly active materials, such as iron oxide or metallic chromium. The most ideal working pressure is 0.055-0.083 MPa of air and 0.55-0.83 MPa of oxygen and as close as possible to working pressures of 10: 1, for example, 0.055 MPa of air to 0.55 MPa of oxygen and 0.083 MPa of air to 0.83 MPa oxygen.

By controlling the ratio of oxidizable / refractory oxide to compensate for changes in the melting point of various refractory oxides, it is possible to create refractory masses of almost any chemical composition. In the flame spraying of MgO (Cr ₂ O ₃ ) Al ₂ O ₃ materials, oxidizing mixtures of one or more aluminum / chromium and / or magnesium can accurately reproduce the chemical composition, achieve low rebound levels (material losses), a large amount and high quality of the production of refractory mass in relation to density and porosity. The most ideal percentage by weight of oxidizing materials in this type of mass was (8-10): 1/2.

 The materials used for refractory oxides can vary over a very wide range of particle size distributions and, at the same time, produce an acceptable refractory mass. The highest quality masses are obtained using refractory grains ranging in size from -10 to USS dust containing less than 2% 200 USS mesh. Other high-quality masses were obtained using refractory grains ranging in size from -100 to USS dust containing over 50% 200 mesh. USS. In general, the refractory mass forms the faster, the coarser the size of the used particle. Excessive percentages of coarse material can cause material to precipitate in the feed sleeve and reduce the rate of formation of the refractory mass.

 Refractory masses are formed at speeds in excess of 907 kg / h. With an increase in the feed rate of the carrier gas / particle mixture and an increase in the size of the venturi and / or spear, it is assumed that a feed rate of 2722 can be achieved / a feed rate of 2722 kg / h can be achieved. It is important to maintain an oxygen / carrier gas ratio between (5-30): 1 oxygen / carrier gas.

PRI me R 1. Refractory blocks / bricks in the tuyere belt of a copper smelting converter close to the working temperature using the proposed method using a mixture consisting of 91% ground RFG bricks, known on the market as Cohart RFG, having a particle size distribution in the range from -12 mesh to USS dust, 5% aluminum powder with an average particle size of 3-15 microns and 4% chromium powder with an average particle size of 3-15 microns. The mixture was fed in an air flow at 0.07 MPa to the venturi at the discharge end of the lance where it was ejected at a speed of 771 kg / h at an oxygen flow under the pressure of 0.7 MPa at fupmenny worn belt, which had a temperature of over 649 ^C. to form a tightly bonded refractory repair mass.

PRI me R 2. The method of example 1 was repeated with the replacement of 20% of the crushed bricks from 93% Cr ₂ O ₃ with a typical particle size distribution from -60 mesh to dust 20% of the bricks of example 1.

 PRI me R 3. The method of example 1 was repeated using 0.5% magnesium powder and 1% additional chromium powder, both with an average micron size of 3-15 microns.

 Example 4. The method of Example 1 was repeated except that 1% of the aluminum powder was replaced by 1% of the RFG bricks, 4% of the aluminum powder and 4% of the chromium powder.

PRI me R 5. The method of example 1 was repeated, but using the following mixture:
Quantity, Medium
wt. the size
MgO grains 59-68 -12 to dust Cr ₂ O ₃ 13-23 -12 to dust Fe ₂ O ₃ 5-9 -12 to dust Al metal powder 5 3-15 μm Cr metal powder 3 3-15 μm Mg metal powder 5 3-15 microns Si metal powder 23-15 microns
PRI me R 6. The method of example 1 was repeated, but using the following mixture, wt. MgO 49-53 Cr ₂ O ₃ 25-27 Fe ₂ O ₃ 4-6 SiO 1-2
Al metal powder 9
Cr metal powder 6
Mg metal powder 5
PRI me R 7. The method of example 1 was repeated, but using the following mixture, wt. MgO 49-53 Cr ₂ O ₃ 25-27 Fe ₂ O ₃ 4-6 SiO 1-2
Al metal powder 9
Cr metal powder 7.5
Mg metal powder 0.5
PRI me R 8. The method of example 1 was repeated, but using the following mixture.

 Purity Mas.

material, MgO 96 63 Cr ₂ O ₃ 93 23
Al metal powder 99.7 5
Cr metal powder 99.9 7
PRI me R 9. The method of example 1 was repeated, but using the following mixture, wt. MgO 63 Cr ₂ O ₃ 23
Al metal powder 7
Cr metal powder 7
PRI me R 10. The method of example 1 was repeated using the following mixture:
Deviation Mas.

cleanliness
material, MgO 96 61.5 Coke dust 97% carbon 24 Al metal powder 99.7 5 Cr metal powder 99.9 9 Mg metal powder 99.9 0.5
PRI me R 11. The method of example 1 was repeated using the following mixture, wt. MgO 60.5
Al metal powder 7
Coke dust 25
Cr metal powder 7
Mg metal powder 5
PRI me R 12. The method of example 1 was repeated, but using the following mixture:
Purity Mas.

material
MgO 97.3 88.5
Al metal powder 99.7 6
Cr metal powder 99.9 5
Mg metal powder 99.9 0.5
PRI me R 13. The method of example 1 was repeated, but using the following mixture:
Purity Mas.

material
AlO 99.8 87 Refractory grain Al metal powder 99.7 4.5 Cr metal 99.9 8 Mg metal 99.9 0.5
PRI me R 14. The method of example 1 was repeated, but using the following mixture, wt.

Alo
Refractory Grain 87
Al metal powder 9 Cr metal 3.5 Mg metal 0.5
PRI me R 15. The method of example 1 was repeated, but using the following mixture:
Purity Mas.

material
Zr ₂ O ₃ Refractory grain 99.5 87 (-50 + 100 mesh) Al metal powder 99.7 4.5 Cr metal powder 99.7 8 Mg metal powder 99.9 0.5
PRI me R 16. The method of example 1 was repeated, but using the following mixture, wt. Zr ₂ O ₃ (50 + 100 mesh) 87 Mg powder 325 x 0.5
PRI me R 17. The method of example 12 was repeated using the following mixture, wt.

SiC 99.5% 200 x mesh 77 SiO ₂ powder 325 x 19.5 Al powder-325 x 3
Mg powder 325 x 0.5
The methods in examples 1 and 4 were carried out using pure oxygen at 0.69 MPa, introduced into the venturi tube of the spray machine and sucking up the compositions of examples 1 and 4 with an approximate speed of 0.45 kg / min. There was a reverse flame slip, which made the compounds unsuitable. Then, the examples were repeated using dilution and relative pressures of oxygen to air (8-12): 1 for speeds of 0.45, 1.36, 4.1, 6.8, and 15 kg / min without reverse flashing, quite serious to prevent their use. The most desirable speeds were in example 1, but all tested mixtures gave associated melted refractory masses.

PRI me R 18. The method according to example 1 is repeated using the same mixture of materials. The mixture was fed into an air stream at 0.0345 MPa venturi on the inlet end of the lance where it is ejected at a speed of 408 kg / h oxygen stream pressurized to 0.345 MPa worn tuyere zone, which was at a temperature above 645 ^{° C} to form a refractory firmly bound repair mass. The volume ratio of oxygen to air was 10: 1.

 PRI me R 19. The method of example 21 was repeated except that the air pressure was 0.104 MPa, the oxygen pressure was 1.04 MPa and the material flow rate was 1034 kg / h.

PRI me R 20. The method according to example 1 was repeated using a mixture consisting of 93% ground RFG bricks, 4% aluminum powder and 3% chromium powder. The mixture was fed into an air stream at 0.0345 MPa in the venturi at the discharge end of the lance where it was ejected at a speed of 953 kg / h at an oxygen flow under the pressure of 1.04 MPa on the worn tuyere belt, which had a temperature of 649 ^{° C} for the formation of a tightly bound refractory repair mass. The volume ratio of oxygen to air was 30: 1.

PRI me R 21. The method of example 1 was repeated using a mixture consisting of 89% ground RFG bricks, 6% aluminum powder and 5% chromium powder. The mixture was fed into an air stream at 0.0863 MPa venturi on the inlet end of the lance where it was ejected at a speed of 499 kg / h at an oxygen flow under the pressure of 0.345 MPa on the worn tuyere belt, which had a temperature of ^about 649 C to form a durable bound refractory mass. The volumetric ratio of oxygen to air was 5: 1.

Claims (5)

 1. The method of forming a refractory coating on the working surface of the lining by mixing particles of refractory and oxidizable materials with a carrier gas, then connecting them to an oxygen stream and spraying onto the surface of the lining, characterized in that, in order to increase efficiency, the connection of the flow of refractory and oxidizable materials in a carrier gas with an oxygen stream is carried out by suction of a stream of refractory and oxidizable materials in a carrier gas with a pressure of 0.0345 0.104 MPa into an oxygen stream with a pressure of 0.345 1.04 Pa with a volume ratio of oxygen and carrier gas (5 30) 1, at least one component from the group is used as a refractory material: chromium oxide, zirconium oxide, silicon oxide, magnesium oxide, aluminum oxide, silicon carbite, iron oxide, and as an oxidizable material, at least one component from the group: chromium, zirconium, silicon, magnesium, aluminum.  2. The method according to claim 1, characterized in that the volume ratio of oxygen and carrier gas is (8 12) 1.  3. A device for forming a refractory coating on the working surface of a lining, comprising a hopper for refractory and oxidizable materials, a feeder, a pipe for a mixture of refractory and oxidizable materials with a carrier gas, an oxygen supply nozzle and a sprayer, characterized in that, in order to increase efficiency, the sprayer is equipped with a suction a device having a narrowing, while the nozzle for supplying oxygen is located coaxially with it, and the pipeline mixture of refractory and oxidizable materials with a carrier gas perpendicular to y.  4. The device according to claim 3, characterized in that the suction device is located on the inlet end of the spray.  5. The device according to claim 3, characterized in that the suction device is placed inside the atomizer.

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