WO2007129927A1

WO2007129927A1 - Method for continuously processing iron oxide-containing materials and a unit for carrying out said method

Info

Publication number: WO2007129927A1
Application number: PCT/RU2006/000230
Authority: WO
Inventors: Anatolij Anatoljevich Golubev; Jurij Alexandrovich Gudim
Original assignee: Obchestvo S Ogranichennoi Otvetstvennostju Promishlennaja Kompanija 'tekhnologija Metallov'
Priority date: 2006-05-05
Filing date: 2006-05-05
Publication date: 2007-11-15

Abstract

The invention relates to metallurgy and can be used for ore processing, including tinatium-magnetite and other iron oxide-containing materials. The inventive method consists in melting a charging material in a smelting room (1) heated by means of fuel-oxygen burners (3) which are provided with flames immersed in melt and mounted at 0.3-0.8 m above the maximum level of a melted slag, in reducing iron by means of carbon-containing materials injected with a heated nitrogen flow by injectors (5, 17) which are located at 0.10-0.40 m above the maximum level of a reduced metal (9), in increasing, during the process, the volume of a reducing zone in the melted slag to 70-80% of the melt volume and in separating it from an oxidising zone, in agitating the slag and metal melts by means of nitrogen which is heated to a temperature of 150-250°C and is injected through porous plugs (13) arranged in the refractory brickwork of the hearth (12) of the smelting room and by released CO bubbles and in simultaneously running off the metal and the incompletely reduced slag in the same ladle (11) through metal and slag discharge spouts which are shifted with respect to each other. Said invention makes it possible to increase performance of the process, the iron recovery degree and to improve the process cost-performance ratio.

Description

Method for continuous processing of materials containing iron oxides and unit for its implementation

The invention relates to metallurgy and can be used for the processing of iron ores, including titanomagnetite, waste slag, dust, sludge from metallurgical production and other materials containing iron oxides.

There are various methods of processing materials containing iron oxides: smelting cast iron in blast furnaces, direct reduction of iron by solid-phase and liquid-phase reduction methods. Blast furnaces, widely used in ferrous metallurgy, have the highest thermal efficiency, but require significant costs for the preparation of iron ore materials, coke production and high capital costs for creating a production cycle. In addition, blast furnaces are not suitable for processing most of the waste slag from metallurgical production, the reserves of which are huge in our country and abroad.

Blast furnaces cannot economically process poor iron ores, as well as iron ores with refractory waste rock. Installations of solid-phase direct reduction of iron also require significant costs for the enrichment and preparation of iron ore raw materials and cannot economically process poor iron ores and waste slag from the metallurgical industry.

Such raw materials can be processed by plants (aggregates) operating on the principle of direct liquid-phase reduction of iron.

Variants of liquid-phase reduction of iron are known by a two-stage process, for example, the DIOS process (Direct Irop Ore

SUBSTITUTE SHEET (RULE 26) Sméltipg), USA, or by the SHSMELT process (High Impact Sméltipg), Australia, in which pre-partially reduced iron ores are used for liquid-phase reduction [1]. But the two-stage processes of liquid-phase reduction of iron are cumbersome in equipment and organization of production, require significant capital costs.

Methods involving a one-stage process of liquid-phase reduction of iron are less cumbersome, the organization of production with such units is much simpler, capital costs are less. Of the one-stage processes of liquid-phase reduction of iron, the ROMELT process created in our country in the 80s is most well known and fairly well developed [1,2]. The reduction of iron using this process occurs in a liquid slag bath obtained from iron oxide-containing charge materials and fluxes, purged with oxygen-containing blast. The source of heat and iron reducing agent in the process is steam coal, which is loaded into the slag melt together with the charge materials. In the slag melt, the processes of coal carbon oxidation to CO ₃ occur with oxygen-containing blast blown into the slag, iron reduction according to the scheme (FeO) + С → Fe + CO _gas and saturation of the reduced iron with carbon. Since carbon carbon is oxidized in the slag only to CO monoxide, little heat enters the bath. In addition, the iron reduction reaction is generally endothermic and proceeds with the absorption of heat from the melt. In order to increase the heat input to the melt in the working space of the ROMELT unit, part of the carbon monoxide released from the bath is burned out according to the CO + Vg O ₂ - → CO ₂ scheme, using gaseous oxygen,

SUBSTITUTE SHEET (RULE 26) blown into the working space with special tuyeres located above the maximum melt level. But at the same time, not all of the carbon monoxide CO has time to burn out to carbon monoxide CO ₂ , and, most importantly, not all of the heat obtained by burning the CO can be transferred to the molten bath, which leads to a significant increase in the consumption of coal and oxidizer (oxygen) for the production of one tons of products and reduced unit performance.

A known method of melting oxidized raw materials of ferrous metals in a furnace with a liquid bath (see copyright certificate SU 1706210 Al), selected by the applicant as the closest analogue of the claimed method.

In the known method, comprising supplying oxygen-containing gas to the slag melt to form a bubbling layer, simultaneously loading carbonaceous reducing agent and iron ore into the bubbling layer, separately releasing slag and metal to increase aggregate productivity and reducing the consumption of carbonaceous reducing agent before simultaneously loading the reducing agent and ore, the bubbling layer saturated with a carbon reducing agent to a volume content of carbon of 5-50% in it, which is retained during melting in those the same limits. To reduce carbon losses when only a carbon reducing agent is loaded into the slag melt, bubbling of the slag layer is carried out by products formed by burning natural gas and / or liquid carbon, an inert gas or a gas with an oxygen content of less than 35%.

The known method of melting oxidized raw materials of ferrous metals in a furnace with a liquid bath has the following disadvantages:

SUBSTITUTE SHEET (RULE 26) - since the unit is heated by coal, which is loaded into the bubbled slag layer and oxidized by oxygen to CO _{5 in} it, a significant underburning of CO is observed and, as a result, increased fuel consumption, causing a significant decrease in the process thermal efficiency;

- intensive mixing (sparging) of the slag melt with cold oxygen-containing gas leads to an increased consumption of carbon reducing agent, an additional decrease in thermal efficiency and a deterioration of the technical and economic parameters of the process;

- when bubbling the melt with oxygen-containing blast supplied through the side tuyeres, it is difficult to separate the oxidation and reduction zones in the melt, which leads to increased metal losses due to its lesser extraction from the ore and, accordingly, a decrease in the process productivity;

- separate (in time and space) release of metal and slag does not allow for additional reduction of slag and refining of metal from carbon, silicon and phosphorus during release;

- pre-saturation of the slag melt with carbon to 5-50% by volume while bubbling the slag melt with products of natural gas or liquid hydrocarbon combustion results in a noticeable decrease in the temperature of the slag melt due to the occurrence of endothermic reactions CO ₂ + C → 2CO and H ₂ O + C → H ₂ + CO, respectively, increasing its viscosity, which makes it difficult to conduct the initial phase of the process due to a slowdown in the distribution of carbon in the melt; the same, but to a lesser extent, will be observed when the melt is sparged with cold inert gas;

SUBSTITUTE SHEET (RULE 26) - when bubbling the slag melt during its saturation with an oxygen-containing gas with an oxygen content of not more than 35%, some oxidation of the loaded carbon will be observed, which will somewhat slow down the initial phase of the process, although to a lesser extent than when bubbling the melt with an inert gas or products of hydrocarbon combustion.

The proposed method for the continuous processing of materials containing iron oxides solves the problem of improving the technical and economic indicators of the process of liquid-phase reduction of iron from materials containing iron oxides.

The technical result of the proposed method for the continuous processing of materials containing iron oxides is to eliminate the disadvantages of the closest analogue, namely:

- increase the thermal efficiency of the unit and increase its productivity;

- an increase in the degree of extraction of iron from the processed charge materials;

- improving the quality of the obtained iron-containing intermediate, taking into account its further use in steelmaking.

Known continuously operating unit for melting the mixture and the implementation of the process of liquid-phase reduction of iron [V.A. Kudrin. Theory and technology of steel production. Moscow. Peace. 2003. Fig. 7.9., P.68.], Selected by the applicant as the closest analogue of the unit for the continuous processing of materials containing iron oxides.

In the known unit, the lower part of the walls of the melting chamber, the hearth and the walls of the adjoining settlers are made of

SUBSTITUTE SHEET (RULE 26) refractory bricks. The upper part of the walls and the vault of the melting chamber are water-cooled. The release of metal and slag is carried out continuously from the respective settling tanks located on opposite sides of the melting chamber, through openings located at different levels, equipped with gutters. Reduction of iron occurs in a liquid slag bath obtained from iron oxide-containing charge materials and fluxes. The heat source and the reducing agent of iron is steam coal, which is loaded into the slag melt together with the charge materials. To burn coal and mix (sparge) the melt, lances are installed in the walls of the melting chamber, blowing oxygen directly into the slag melt. In order to burn carbon monoxide CO emitted from the melt to carbon dioxide, having received an additional amount of heat, part of which is transferred to the melt, an additional row of tuyeres is installed above the slag melt, which supply oxygen to the free space of the chamber.

Known continuously operating unit for melting the mixture and the implementation of liquid-phase reduction processes has the following disadvantages:

- since the heat necessary for the implementation of the process is obtained due to the oxidation of coal located in the slag melt, blown into the melt with oxygen or an oxygen-containing gas, the volume of the reduction zone in the slag melt is small, it can change, the reduction of iron is difficult, proceeds at a relatively low speed and not until the end, therefore, the performance of the unit is small, and the degree of extraction of iron from the mixture is not high enough;

SUBSTITUTE SHEET (RULE 26) - the upper water-cooled part of the walls is subjected to intense thermal irradiation during the afterburning of CO with oxygen supplied by the tuyeres of the second (upper) row, which leads to the need for periodic repair of water-cooled elements carried out on a stopped furnace and a decrease in unit productivity;

- during operation of the unit due to oxidation (burning) of coal in the slag melt to CO, a significant underburning of CO is observed, as a result of which increased fuel consumption causes a decrease in the thermal efficiency of the unit and a deterioration of the technical and economic parameters of the process;

- when bubbling the melt with oxygen-containing blast supplied through the lower side tuyeres, it is difficult to separate the oxidation and reduction zones in the melt, which leads to an increased consumption of reducing agent;

- separate (in time and space) release of metal and slag does not allow for additional reduction of slag and refining of metal from carbon, silicon and phosphorus.

The proposed unit for the continuous processing of materials containing iron oxides solves the problem of improving the design of the device for the continuous melting of charge materials and liquid-phase reduction of iron, increasing its productivity and improving the technical and economic indicators of the method of continuous processing of materials containing iron oxides.

The technical result of the proposed unit for the continuous processing of materials containing iron oxides is to eliminate the disadvantages of the closest analogue, namely:

- increase in productivity, thermal efficiency;

SUBSTITUTE SHEET (RULE 26) - an increase in the degree of extraction of iron from the processed charge materials;

- reduction of fuel, reducing agent and oxygen consumption, improvement of technical and economic indicators of production;

- improving the quality of the obtained iron-containing product. The technical result is achieved by the following solutions, united by a common inventive concept.

The technical result is ensured by the fact that in the method for the continuous processing of materials containing iron oxides, including loading charge materials into the melting chamber, melting them, reducing iron with carbon, releasing the obtained metal and slag, according to the first invention, the volume of the reduction zone in the slag melt is increased to 70- 80% of the volume of the melt and delimit it with the oxidation zone, for this, the melting of the charge materials is carried out in a melting chamber with a cooled liquid metal heat the carrier with a casing of heat installed 0.3-0.8 m above the maximum level of the slag melt of fuel-oxygen burners with torches immersed in the melt; iron is reduced by carbon-containing materials injected into the stream of heated nitrogen by injectors located 0.10-0.40 m above the maximum level reduced metal, mixing the slag and metal melts is carried out heated in the heat exchangers of the cooling circuit, the heat of the cooled liquid metal coolant to 150-250 ⁰ C nitrogen, vd washed through porous plugs in the refractory lining of the bottom of the melting chamber, and bubbles of carbon monoxide CO released from the slag melt during iron reduction.

SUBSTITUTE SHEET (RULE 26) The slag melt in the melting chamber is not restored, the slag containing 5-15% of iron oxides is poured from the melting chamber simultaneously with the obtained iron-carbon alloy into one ladle, while the slag is reduced, and the iron-carbon alloy is refined from undesirable impurities: carbon, silicon, phosphorus, etc. .d.

The dust trapped in the system for capturing and treating gases leaving the unit is blown with a special injector into the slag melt located in the melting chamber, using nitrogen heated to 150-250 ⁰ C as the carrier gas.

The slags obtained after processing materials containing iron oxides are granulated and used in cement production.

The main steelmaking converter slag is used as the charge material, and the resulting final slag after granulation is used as a Portland cement clinker.

The mixture is heated before being loaded into the melting chamber and the iron is partially reduced in it on the conveyor passing through the hermetic casing by the process gases leaving the melting chamber.

The technical result is also ensured by the fact that in the unit for the continuous processing of materials containing iron oxides, containing a melting chamber with a cooled liquid metal coolant casing, in the working space of which there is a recovered slag melt and recovered metal, a cooling circuit of the metal coolant, charge materials loading system, heat recovery and gas purification, metal and slag discharge, according to the second invention, for melting

SUBSTITUTE SHEET (RULE 26) of the charge being loaded and heating of the slag melt, the melting chamber is equipped with fuel-oxygen burners installed 0.3-0.8 m higher than the maximum level of the slag melt; for the injection of carbon-containing materials and dust trapped in the gas purification into the slag melt, the chamber is located 0.10-0.40 m higher the maximum level of the recovered metal by injectors, for the conveyor loading of charge materials and the selection of process gases, the chamber has a common hole located above the level of the slag melt in the side forming a casing, nitrogen is used in the heat exchangers of the cooling circuit to cool the metal coolant, which is then used to inject carbon-containing materials and dust into the slag melt, and porous plugs are blown into the melt through the hearth lining installed in the lining, and the slag and metal chutes are displaced relative to each other friend, providing the possibility of simultaneous discharge into one bucket of metal and unreduced slag.

In this case, the longitudinal axis of the troughs for the release of metal and slag are shifted in the horizontal plane by an angle of 5 - 25 degrees.

An increase in the volume of the reduction zone in the slag melt in the melting chamber to 70–80% of the volume of the melt and its delimitation with the oxidation zone of the melting chamber, the volume of which is equal to the total volume of burners plunged into the melt, creates favorable conditions for a more complete and faster reduction of iron from downloadable charge materials, which allows to increase the productivity of the process and the degree of extraction of iron from the charge, as well as improve the technical and economic indicators of the process.

SUBSTITUTE SHEET (RULE 26) Heating the unit with fuel-oxygen (gas-oxygen or mazuto-oxygen) burners with torches immersed in the melt provides a significantly lower amount of unburned monoxide during the process, which reduces the overall fuel consumption, increases thermal efficiency and increases the productivity of the melting unit, due to better heat transfer conditions and, accordingly, less heat loss with flue gases.

The use of cooling the casing of the unit with a liquid metal coolant (Na) allows better cooling of the chamber walls in the slag zone, which makes it possible to obtain a stable slag skull and, accordingly, increase the productivity of the unit.

The injection of carbon-containing materials with a slight excess against the calculated in a stream of heated nitrogen injectors into the slag melt at an altitude of 0.10-0.40 m above the maximum level of the reduced metal allows creating good conditions for the reduction of iron from iron oxides of the slag and at the same time avoiding excessive carburization metal melt.

The refusal of sparging the slag melt with oxygen-containing gas injected by the side tuyeres into the slag melt allows one to reduce the oxygen consumption for the process, more clearly distinguish (separate) the oxidation and reduction zones of the slag melt, reduce heat losses of the unit, reduce the amount of dust released from the unit with technological gases.

Organization of melt mixing with nitrogen heated to 150--250 ^° C in heat exchangers where metal is cooled

SUBSTITUTE SHEET (RULE 26) the coolant blown into the melt through porous plugs in the lining of the bottom of the melting chamber, in combination with the action of carbon monoxide bubbles emitted during iron reduction, provides sufficient mixing of the cinder metal bath for the recovery processes to occur and the metal beads to precipitate. In this case, the bath is slightly cooled, and the total thermal efficiency of the unit increases.

The simultaneous discharge of metal and unreduced slag with an iron oxide content of 5-15% into one ladle from the melting chamber allows to increase the productivity of the melting unit by reducing the slag melt residence time in it, to quickly restore slag due to a significant increase in the slag-metal contact surface in the ladle to an iron oxide content of 2-6% and refine the resulting iron-containing metal from undesirable impurities: carbon, silicon, phosphorus.

The injection of dust into the slag melt with a special injector in a stream of heated nitrogen trapped in the unit’s gas capture and purification system reduces environmental pollution and increases the degree of extraction of iron from charge materials.

Granulation of the final slags obtained in the aggregate allows their use as useful additives in the production of cement.

During processing in the melting chamber of the main steelmaking slags of the converter production, the final slag of the process in chemical and mineralogical composition (after quenching as a result of granulation) corresponds to Portland cement clinker and can be used as such in the production of Portland cement.

SUBSTITUTE SHEET (RULE 26) Heating the charge before loading it into the melting chamber and partially recovering the charge iron on the conveyor passing through the sealed casing by the process gases leaving the melting chamber reduces the fuel and oxygen consumption for heating the chamber, accelerates the processes of charge melting and iron reduction and increases the unit's productivity.

The use in the unit of continuous processing containing iron oxides for its heating (melting the charge and compensating for the cost of heat for endothermic iron reduction reactions) located 0.3-0.8 m above the melt of fuel-oxygen burners with torches immersed in the melt can dramatically reduce the amount of oxidation zone in the melt and, accordingly, increase the productivity of the unit, as well as increase the degree of extraction of iron from charge materials.

The use for injecting a carbon-containing reducing agent into the melt and the dust trapped in the filters located 10.0–40.0 m above the maximum level of the reduced metal of injectors using heated nitrogen as the carrier gas leads to a decrease in the volume of the oxidation zone in the melt and, accordingly, an increase in the volume recovery zone, increase unit productivity and the degree of extraction of iron from charge materials.

The presence in the lateral generatrix of the casing of a common opening for the selection of process gases and the loading of charge materials allows to improve the layout of the unit in the building of the workshop and organize heating and partial recovery of charge materials by process gases, which gives

SUBSTITUTE SHEET (RULE 26) the ability to reduce capital costs and fuel consumption in the production process.

The use of a cooling circuit in heat exchangers for cooling liquid metal coolant nitrogen allows the use of nitrogen heated to 150 - 25O ⁰ C for injection of materials into the melt and melt mixing (feeding through porous plugs in the lining of the unit bottom), which makes it possible to improve the course of charge melting and reduction iron, increase productivity, reduce heat loss of the unit and reduce fuel consumption.

The offset of the longitudinal axes of the gutters for the release of slag and metal in a horizontal plane at an angle of 5 - 25 degrees allows you to simultaneously merge into one bucket the metal and unreduced slag.

The essence of the claimed method is illustrated and the unit for its implementation is illustrated by drawings.

In fig. 1 shows a general view of an apparatus for the continuous processing of materials containing iron oxides.

In fig. 2 shows section A-A in Fig. 1.

The method of continuous processing containing iron oxides of materials is as follows.

The charge materials are loaded into the melting chamber, melted, iron is reduced with carbon, and the resulting metal and slag are released. The volume of the reduction zone in the slag melt is increased to 70-80% of the volume of the melt and delimits it with the oxidation zone. The melting of charge materials is carried out in a melting chamber with a cooled liquid metal coolant casing heat installed

SUBSTITUTE SHEET (RULE 26) ₅ to 8m 0,3-0 above the maximum level of molten slag-fuel burners with torches immersed in the melt. The reduction of iron is carried out with carbon-containing materials, injected in a stream of heated nitrogen by injectors located 0.10-0.40 m above the maximum level of the reduced metal. Mixing the slag and metal melts is carried out with the heat of the cooled liquid metal coolant heated in heat exchangers of the cooling liquid metal to 150-250 ⁰ C with nitrogen, injected through porous plugs in the refractory lining of the bottom of the melting chamber, and with carbon monoxide bubbles CO released from the slag melt during iron reduction. The slag melt in the melting chamber is not restored, the slag containing 5-15% of iron oxides is poured from the melting chamber simultaneously with the obtained iron-carbon alloy into one ladle, while the slag is reduced, and the iron-carbon alloy is refined from undesirable impurities: carbon, silicon, phosphorus, etc. .d. The dust trapped in the system for capturing and treating gases leaving the unit is blown with a special injector into the slag melt located in the melting chamber, using nitrogen heated to 150-250 ⁰ C as the carrier gas. The slags obtained after processing materials containing iron oxides are granulated and used in cement production. The main steelmaking converter slag is used as the charge material, and the resulting final slag after granulation is used as a Portland cement clinker. The mixture is heated before being loaded into the melting chamber and partially restored in it

SUBSTITUTE SHEET (RULE 26) iron on a conveyor passing through a sealed casing, process gases leaving the melting chamber.

The unit for continuous processing of materials containing iron oxides contains a melting chamber 1 with a casing 2 cooled by a liquid metal coolant, in the working space of which there is a restored slag melt 4, limited by walls with a skull 6, and metal 9 in a lined bath 8, 12. To melt the charge being loaded ( charge in the figure is not shown) and heating the slag melt 4, the melting chamber 1 is equipped with fuel and oxygen burners 3 installed at 0.3 - 0.8 m above the maximum level of the slag melt 4 For injection of carbon-containing materials and dust trapped in gas purification 20 into slag melt 4, chamber 1 is equipped with injectors 5 and 17 located at 0, 10 - 0.40 m above the maximum reduced metal level 9. There is a refractory lining of walls 8 of a liquid metal metal bath 9. For conveyor loading of charge materials and selection of process gases, the chamber 1 has a common opening 21 located above the level of the slag melt 4 in the side generatrix of the casing 2, connected to a sealed casing 19 containing the conveyor 18. In heat exchangers 16 of the cooling circuit 14 - 15 use nitrogen to cool the metal coolant (not shown), which is then used to inject 4 carbon-containing materials and dust into the slag melt and blow porous plugs 13 into the melt 4 through the hearth lining 12 installed in the lining The longitudinal axis of the groove 7 for draining the slag and the longitudinal axis of the groove 10 for draining the metal into the bucket 11 are displaced in a horizontal plane relative to each other by

SUBSTITUTE SHEET (RULE 26) an angle of 5 - 25 degrees, providing the possibility of simultaneous discharge into one ladle of metal and unreduced slag.

The operation of the unit is as follows.

Loading, feeding into the melting chamber 1 and heating the charge is carried out by a conveyor 18 with an airtight casing 19 connected to the gas purification system 20. The charge (not shown) loaded through the opening 21 of the chamber 1 is heated to the slag melt 4 due to the heat of fuel-oxygen (gas-oxygen or oil-oxygen) ) burners 3, the torches of which are immersed in the melt 4. Since the casing 2 of the unit is made of a cooled liquid metal coolant (Na), the cooling of the walls of the chamber 1 in the slag zone 4 makes it possible to obtain a stable lacquer ledge 6, which consequently increases the productivity of the unit as a whole. Injectors 17 inject heated nitrogen into the slag melt 4 in a stream of carbon-containing materials with a slight excess against the calculated one at a height of 0.10-0.40 m above the maximum level of the reduced metal 9, which creates good conditions for the reduction of iron from iron oxides of slag without unnecessary carbonization of the metal melt. During the process, the volume of the reduction zone is increased to 70-80% of the volume of melt 4, more clearly delineating (separating) the oxidation and reduction zones of the slag melt and reducing the amount of dust released from the unit with process gases. In the heat exchanger 16, where the metal coolant is cooled, nitrogen is heated to 150-250 ⁰ C, injected into the melt through porous plugs in the lining of the bottom of the melting chamber 1, mixing the slag melt 4 and the metal melt 9. By mixing the slag metal

SUBSTITUTE SHEET (RULE 26) baths, combinations of the effects of carbon monoxide bubbles emitted during iron reduction, and the deposition of metal kings, recovery processes proceed rather quickly. In this case, the bath is slightly cooled, and the total thermal efficiency of the unit increases. At the same time, metal 9 and unreduced slag 4 with an iron oxide content of 5-15% in one ladle 11 are drained from the melting chamber 1, reducing the residence time of the slag melt 4 in it, and quickly reducing the slag due to a significant increase in the slag-metal contact surface in the ladle 11 to a content of iron oxides of 2-6% and refining of the obtained iron-containing metal from undesirable impurities: carbon, silicon, phosphorus.

The dust captured in the gas capture and purification system 20 of the unit is blown into the slag melt 4 by a special injector 17 in a stream of heated nitrogen, which allows to reduce environmental pollution and increase the degree of extraction of iron from charge materials.

Examples of specific implementation, confirming the possibility of implementation of the proposed method. Example 1

The heating of the slag furnace, which was successfully used for the smelting of calcareous-alumina synthetic slag, with oxygen-borne torches with torches immersed in the melt, is described in the monograph [4]. Therefore, the possibility of using burners of this type to implement the proposed method is not in doubt. Example 2

SUBSTITUTE SHEET (RULE 26) The injection of carbon-containing materials by injectors in a carrier gas stream into the slag melt is widely and successfully used in the modern technology of steel production in arc furnaces [5], as well as in the modern technology of out-of-furnace steel processing in steel pouring ladles [1]. Therefore, the use of this option for introducing a carbon reducing agent into the slag melt for the implementation of the proposed method is quite possible. Example 3

Purging the slag-metal melt with inert gas through porous plugs in the bottom lining is used to mix the melt and steel in arc furnaces [6] and to mix the metal and slag in steel casting ladles during out-of-furnace steel refining [1].

Example 4

Bearing steel of the brand IUXl 5 SG with a high content of carbon and silicon, melted in the main arc furnace, was poured from the furnace into a ladle with fireclay lining together with oxidized furnace slag (8% by weight of metal), which had the following average composition according to the results of 5 experimental melts, %:

CaO SiO ₂ MgO Al ₂ O ₃ Σ FeO

55.3 21.3 10.6 6.1 5.8

After the release, samples of metal and slag were taken from the bucket.

The average composition of ladle slag (for 5 experimental heats) was as follows,%:

CaO SiO ₂ MgO Al ₂ O ₃ Σ FeO

56.1 24.7 10.3 6.4 1.8

SUBSTITUTE SHEET (RULE 26) In the metal, the carbon content decreased by 0.10% ₅ silicon by 0.2%, manganese by 0.2%.

The results obtained indicate the possibility of additional reduction of slag by the metal and refining of metal from carbon and silicon during the implementation of the proposed method, when the multiplicity obtained will be several times higher than in the experiments conducted by the author. Example 5

In a laboratory resistance furnace, 250 grams of converter slag containing 20% iron oxides were molten in a molybdenum crucible, 12 grams of carbon powder were added, and the melt was stirred at a temperature of 1620 ⁰ C for 20 minutes. After the experiment, the following results were obtained (according to the results of 3 experiments):

As can be seen from the table, the composition of the slag after its partial recovery is close to the composition of Portland cement clinker. it

SUBSTITUTE SHEET (RULE 26) indicates the possibility of obtaining Portland cement clinker when implementing the proposed method for the continuous processing of materials containing iron oxides. Literature.

1. V.A. Kudrin. Theory and technology of steel production. Moscow. Peace. 2003.

2. A. B. Usachev. Development of theoretical and technological foundations for the production of pig iron by the liquid-phase reduction process ROMELT. Abstract of dissertation for the degree of Doctor of Technical Sciences. Moscow. 2003.

3. Copyright certificate SU 1706216 Al. "A method of melting oxidized raw materials of ferrous metals in a furnace with a liquid bath." Applicant: Moscow Institute of Steel and Alloys. Authors: Romenets BA, Vanyukov AB, Usachev A.B., Ugarov AA, Bystrov B.P., Valavin V. C ₅ Grebennikov V.R., Glovatsky A.B.

4.S.G. Voinov, A.G. Shalimov, L.F. Kosoy, E.S. Kalinnikov. Refining became synthetic slags. M. “Metallurgy”. 1970, 461 p.

5. V. Stein, L. Garten, O. Lange. the use of modern technology in the reconstruction of 150 tons of electric arc furnaces. "Electricity". 2005. N_> 9, p. 9-15.

6. I.V. Derevyanchenkov, G.A. Lozin, E.A. Schumacher et al. Improving the energy supply of a modern electric melting process. Steel. 2005 N ° l, p. 45-50.

SUBSTITUTE SHEET (RULE 26)

Claims

Claim

1. A method for the continuous processing of materials containing iron oxides, including loading charge materials into the melting chamber, melting them, reducing iron with carbon, releasing the obtained metal and slag, characterized in that the volume of the reduction zone in the slag melt is increased to 70 - 80% of the volume of the melt and demarcate it with the oxidation zone, for this, the charge materials are melted in a melting chamber with a heat-shielded metal coolant casing with heat installed 0.3 - 0.8 m higher than max level of the slag melt of fuel-oxygen burners with torches immersed in the melt, iron is reduced by carbon-containing materials, injected in a stream of heated nitrogen by injectors located 0.10 - 0.40 m above the maximum level of the reduced metal, mixing of slag and metal melts is carried out heated in the heat exchangers of the circuit cooling the cooled metal coolant heat to 150 - 250 ⁰ C with nitrogen blown through the porous plug in the refractory lining of the hearth lavilnoy chamber and bubbles of carbon monoxide, CO, emitted from the melted slag in the reduction of iron oxides.

2. The method according to p. 1, characterized in that the slag melt in the melting chamber is unreduced, the slag containing 5 to 15% iron oxides is drained from the melting chamber simultaneously with

SUBSTITUTE SHEET (RULE 26) obtained iron-carbon alloy in one bucket, while the slag is re-reduced, and the iron-carbon metal alloy is refined from undesirable impurities: carbon, silicon, phosphorus.

3. The method according to claim 1, characterized in that the dust trapped in the system for collecting and purifying gases leaving the unit is blown with an injector into the slag melt located in the melting chamber, using nitrogen heated to 150-250 ⁰ C as the carrier gas .

4. The method according to claim 1, 2, 3, characterized in that the slags obtained after processing materials containing iron oxides are granulated and used in the production of cement.

5. The method according to p. 1,2,4, characterized in that the main steelmaking converter slag is used as the charge material, and the resulting final slag after granulation is used as a Portland cement clinker.

6. The method according to p. 1, 2, 3, 4, 5, characterized in that the charge is heated and partially reduced in the iron before loading into the melting chamber on a conveyor passing through a sealed casing, technical gases leaving the melting chamber.

7. A unit for the continuous processing of materials containing iron oxides, containing a melting chamber with a cooled liquid metal coolant casing, in the working space of which there is a recovered slag melt and recovered metal, a cooling circuit for a metal coolant, charge materials loading system, heat recovery and gas purification, metal discharge and slag, characterized in that for melting the charge and heating the slag melt, the melting chamber is equipped with and 0.3 - 0.8 m

SUBSTITUTE SHEET (RULE 26) higher than the maximum level of slag melt by fuel-oxygen burners, the chamber is equipped with injectors located 0.10 - 0.40 m above the maximum level of the recovered metal by injectors for blowing carbon-containing materials and dust trapped in the gas purification, the chamber has a conveyor loading of charge materials and selection of process gases a common hole located above the level of the slag melt in the side generatrix of the casing in the heat exchangers of the cooling circuit for cooling the metal coolant Nitrogen is used, which is then used for injection of carbon-containing materials and dust into injections into the slag melt, and porous plugs are blown into the melt through the hearths installed in the lining and slag and metal drains are displaced relative to each other, allowing simultaneous discharge into one metal bucket and unreduced slag.

8. The unit for continuous processing of materials containing iron oxides according to claim 7, characterized in that the longitudinal axis of the troughs for the release of metal and slag are offset in the horizontal plane by an angle of 5 - 25 degrees.

SUBSTITUTE SHEET (RULE 26)