WO2014098300A1 - Reduced-iron production method and production device - Google Patents

Abstract

The present invention relates to a reduced-iron production method and production device, and, more specifically, relates to a reduced-iron production method and production device whereby reduced iron having an outstanding rate of reduction is produced by using iron ore containing large amounts of the impurities phosphorus, zinc and alkali elements within the iron ore, while at the same time the phosphorus, zinc and alkali elements are recovered.

Description

Reduced iron manufacturing method and manufacturing apparatus

The present invention relates to a method and apparatus for producing reduced iron, and more particularly, to recover phosphorus, zinc and alkali elements while producing reduced iron having excellent reduction rate by using iron ore containing a large amount of phosphorus, zinc and alkali elements as impurities in iron ore. It relates to a reduced iron production method and a manufacturing apparatus.

In blast furnaces, converters and electric furnaces, reduced iron is used as a raw material for forming molten iron or molten steel.

Reduced iron is a source of reduced iron oxides such as iron ore or iron oxide with a carbonaceous reducing agent (hereinafter referred to as " coal ash ") or a reducing gas. Direct iron making is mainly used to obtain reduced iron.

In the case of the general direct reduced iron (DRI) manufacturing process has been developed a process for producing direct reduced iron by inducing reduction in a rotary hearth furnace (RHF) after the production of ultra-fine iron ore into pellets.

For example, a method of manufacturing reduced iron using a rotary hearth furnace is "a method for producing reduced iron pellets and a method for producing pig iron (published patent 10-2010-0043095); Patent Literature 1", "Method for producing reduced iron (published patent) 10-2010-0122946; Patent Document 2) and the like.

Patent Document 1 and Patent Document 2 both relate to a technique for producing reduced iron using a rotary furnace, and in particular, Patent Document 1 is a technique for improving the reactivity by managing the particle size of the raw material for the purpose of increasing the metallization rate in the production of reduced iron Patent Document 2 relates to a technique for producing reduced iron from iron ore containing zinc at a high concentration.

Conventional rotary furnaces for producing reduced iron are hermetically sealed and reduce iron ore in a reducing atmosphere of up to 1,350 ° C. Therefore, there is a difficulty in controlling the furnace in a reducing atmosphere, and the production volume is 150,000 to 500,000 tons. Mass production had a limit.

Thus, there is a need for a new method for producing reduced iron that exceeds the limits of a rotary furnace for mass production of reduced iron.

Accordingly, in the past, a process for producing a partial reduction ore using an oxidizing atmosphere firing furnace has been proposed, but due to the combustion of oxygen as a reducing agent due to combustion with oxygen in the ambient atmosphere, rather than the amount of carbon used as a reducing agent for iron ore by the oxidizing atmosphere in the firing furnace. There is a problem that the reduction efficiency of iron ore is low because the amount of the heat used for combustion is relatively high and the utilization rate of carbon used for reduction is low.

In addition, in the case of using a calcination furnace in an oxidizing atmosphere, iron ore has a problem that the reduction rate cannot be increased because reoxidation occurs by the surrounding oxidizing atmosphere.

On the other hand, phosphorus (P), zinc (Zn) and alkali oxides (K 2 O + Na 2 O) contained in the iron ore is an impurity that causes various defects when contained in the final product too, conventionally such impurities, that is, phosphorus (P) Reduced iron was produced using iron ore containing less zinc (Zn) and alkali oxides (K2O + Na2O).

However, in recent years, as the depletion of high-quality iron ore containing less impurities, the value of high-quality iron ore is increased, and there is a limit in producing reduced iron with only high-quality iron ore. Thus, a technique of removing such impurities in the steelmaking process has been proposed, but in order to remove impurities in the steelmaking process, it is inevitable to add various subsidiary materials and add a process for removing impurities, thereby increasing production costs.

[Preceding technical literature]

[Patent Documents]

(Patent Document 1) Published Patent 10-2010-0043095 (2010. 04. 27)

(Patent Document 2) Published Patent 10-2010-0122946 (2010. 11. 23)

The present invention provides a reduced iron production method and apparatus for producing reduced iron in an open reduction furnace of an oxidizing atmosphere.

In particular, it provides a method and apparatus for producing reduced iron which can form compacted ore using a mixture of iron ore and carbonaceous material in advance and sufficiently reduce it in a reducing furnace in an oxidizing atmosphere.

In addition, the present invention produces reduced iron using iron ore high in phosphorus (P) content, iron ore high in zinc (Zn), iron ore high in alkali oxide (K 2 O + Na 2 O) content to reduce the iron ore raw material can be widened Provided are a manufacturing method and a manufacturing apparatus.

In addition, the present invention provides a reduced iron production method and apparatus for separating and recovering phosphorus (P), zinc (Zn) and alkali oxides (K 2 O + Na 2 O) in the iron ore production process.

Reduction iron production method according to an embodiment of the present invention comprises the steps of mixing the iron material and carbonaceous material containing phosphorus, zinc and alkali oxides to form a mixture; Shaping the mixture into compacted light; Separating phosphorous, zinc and alkali elements contained in the compacted light while reducing the compacted light in an open reduction furnace; Crushing the reduced product of the compacted ore into a slag including reduced iron and phosphorus; The separated reduced iron is compacted and the slag is recovered.

In the step of forming the mixture, the mixture is characterized in that it contains at least 0.06% phosphorus (P), at least 0.02% zinc (Zn) and at least 0.1% alkali oxide (K 2 O + Na 2 O).

In the step of forming the mixture, the iron raw material is at least one of iron ore with a phosphorus (P) content of 0.06% or more, iron ore with a zinc (Zn) content of 0.02% or more and iron ore having an alkali oxide (K2O + Na2O) content of 0.1% or more It is characterized in that the above iron ore is mixed.

In the step of forming the mixture, the carbon material is characterized in that one or more of the coal-containing dust generated in the coal and steel process is mixed.

In the step of forming the mixture, the mixture is characterized in that the basicity (CaO / SiO2) is at least one.

In the step of forming the mixture, the mixture is characterized in that the content of the alkali oxide is adjusted to 0.5% or more.

In the step of forming the mixture, the mixture is further mixed with a subsidiary material for adjusting the basicity and the content of the alkali oxide, the secondary raw material is characterized in that CaO is used for the basicity control, Na2CO3 and K2CO3 is used for the alkali oxide content control It is done.

The carbonaceous material is characterized in that 10 parts by weight or more are mixed with respect to 100 parts by weight of the total mixture.

In the step of reducing the compacted light in an open reduction furnace, the inside of the reduction furnace is maintained in an oxidizing atmosphere, the gas generated by the reduction of carbon in the compacted light when reducing the compacted light surrounds the gaseous film surrounding the vicinity of the compacted light It is characterized by blocking the oxidative atmosphere and compacted light.

In the step of reducing the compacted light in an open reduction furnace, the calcined temperature of the compacted light is 1000 ℃ or more, the maximum value of the reduced time of the compacted light is characterized in that until the carbon (C) in the compacted light is completely consumed do.

In the step of reducing the compacted ore in an open reduction furnace, zinc (Zn) contained in the compacted ore in the reduction furnace is recovered as dust in exhaust gas in a gaseous phase, and the recovered dust is converted into zinc oxide (ZnO). Separation recovery is characterized in that the process is further made.

The vaporized zinc (Zn) generated during the reduction of the compacted light in the reduction furnace is discharged together with the exhaust gas, the zinc oxide (ZnO) is generated by the reaction of the vaporized zinc (Zn) and oxygen in the exhaust gas, the zinc oxide (ZnO) ) Is included in the dust and is recovered.

The alkali element is separated and recovered with water during the crushing of the recovered dust.

In the separating of the reduced iron and slag, the reduced iron and slag is characterized in that separated by a magnetic separator.

In another aspect, the reduced iron manufacturing method according to an embodiment of the present invention is characterized in that the iron raw material and the carbon material is mixed to form a compacted ore, and the reduced ore is reduced in an open reduction furnace to produce reduced iron.

The carbonaceous material is mixed with 10 parts by weight or more based on 100 parts by weight of the total compacted light, and the gas generated by the reduction of the compacted light by carbon in the reduction of the compacted light forms a gas film surrounding the vicinity of the compacted light to form an open reduction furnace It is characterized by blocking the oxidizing atmosphere in the inside and the compacted light.

On the other hand, the reduced iron manufacturing apparatus according to an embodiment of the present invention and a plurality of raw material hopper that stores different kinds of iron ore; A carbon material hopper in which carbon material is stored; A mixer which forms a mixture by mixing different kinds of iron ore and carbon material ejected from the raw material hopper and the carbon material hopper; A first molding machine for molding the mixture into compacted light; An open reduction furnace of an oxidative atmosphere for reducing the compacted light; A crusher for crushing the reduced product reduced in the reduction furnace; A magnetic separator for separating the pulverized reducing product into reduced iron and slag by magnetic force; And a second molding machine for molding the reduced iron.

A collector for collecting dust in the exhaust gas exhausted from the reduction furnace; It further comprises a hydride group for crushing the dust collected in the collector to separate the zinc oxide (Zn) and the alkaline element-containing waste water.

According to an embodiment of the present invention, there is an effect that a large amount of reduced iron can be produced in an open reduction furnace in an oxidizing atmosphere by utilizing iron ore, which was previously impossible to use due to high impurities in iron ore in the iron making process.

In other words, as the compacted light is formed by using a mixture of iron ore and carbon material in advance, the compacted light is reduced in an oxidizing atmosphere, and the compacted gas is surrounded by the gas layer by the reducing gas generated in the compacted light. Since it is blocked, there is an effect that the compacted light can be sufficiently reduced even in an oxidizing atmosphere.

In addition, phosphorus (P), zinc (Zn) and alkali oxides (K2O + Na2O), which are impurities contained in iron ore, are effectively used during the reduction process, and thus phosphorus (P), zinc (Zn) and alkali oxides (K2O + Na2O). There is an effect that can be separated and recovered from iron.

Accordingly, the width of the iron ore raw material can be widened, thereby lowering the raw material purchase cost and recycling the separated and recovered phosphorus (P), zinc (Zn) and alkali oxides (K2O + Na2O).

1 is a view schematically showing a configuration of a reduced iron manufacturing apparatus and a reduced iron manufacturing method according to an embodiment of the present invention,

Figure 2 is a graph showing the relationship between the phosphorus recovery in the slag according to the basicity after reducing the compacted light at 1200 ℃ 20 minutes,

Figure 3 is a graph showing the relationship between the phosphorus yield in the slag according to the alkali oxide content in the compacted light after reducing the compacted light having a basicity of 20 minutes at 1200 ℃,

Figure 4 is a graph showing the relationship between the metallization rate of the compacted light according to the temperature and the amount of coal ash mixture in the open reduction furnace.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

For the preferred description of the present invention will be described first with respect to the reduced iron manufacturing apparatus for implementing the reduced iron manufacturing method according to an embodiment of the present invention.

1 is a view schematically showing a configuration of a reduced iron manufacturing apparatus and a reduced iron manufacturing method according to an embodiment of the present invention.

As shown in the drawing, the reduced iron manufacturing apparatus according to an embodiment of the present invention includes a first crusher 11 for crushing iron ore; A plurality of raw material hoppers 21, 22, and 23 in which the iron ore crushed in the first crusher 11 is classified and stored according to types; A second crusher 12 for crushing carbonaceous material such as coal; A carbon material hopper 30 in which carbon material crushed by the second crusher 12 is stored; A mixer 50 for mixing iron ore and carbon materials of different types ejected from the raw material hoppers 21, 22, and 23 and the carbon material hopper 30 to form a mixture; A first molding machine (61) for molding the mixture into compacted light; An open type reduction furnace 70 in an oxidative atmosphere for reducing the compacted light; A third crusher (13) for crushing the reduced product reduced in the reduction furnace (70); A magnetic separator (80) separating the crushed reduced product into reduced iron and slag by magnetic force; And a second molding machine 62 for molding the reduced iron. And at least one secondary raw material hopper 40 for storing the secondary raw material; A collector 90 for collecting dust in the exhaust gas exhausted from the reduction furnace; A crusher 100 for crushing the dust collected by the collector 90 to separate the zinc oxide (Zn) and the alkaline element-containing waste water.

The open reduction furnace 70 is a reduction furnace in which the inside is not sealed and is open. If the compacted light can be heated while continuously transferring the compacted light, the reducing furnace of various types may be applied without being limited to a specific shape. For example, to describe the open reduction furnace, a conveying means for conveying the compacted light by a conveyor method is provided. In addition, the upper part of the conveying means is provided with a main body to form a space that is reduced to surround the area in which the compacted light is transferred, the inside of the main body is provided with a plurality of burners to heat the inside of the main body. In addition, the lower portion of the transfer means is provided with suction means for sucking the internal air of the main body. Thus, as the compacted light is transferred by the conveying means, heat is supplied from the upper portion of the compacted light to the lower direction by combustion of the burner and suction of the suction means in the main body. By using an open reduction furnace in this way, the compacted light can be laminated in multiple layers, and the reduction can be continuously performed, thereby producing a large amount of reduced iron.

On the other hand, the first molding machine 61 and the second molding machine 62 uses a twin roll molding machine.

Next, a method for producing reduced iron using the reduced iron manufacturing apparatus configured as described above will be described.

As shown in FIG. 1, various types of iron ore are crushed in the first crusher 11 and stored in a plurality of iron raw material hoppers 21, 22, and 23 according to their respective types. At this time, the iron ore used is an iron ore having a phosphorus (P) content of 0.06% or more, an iron ore having a zinc (Zn) content of 0.02% or more, and an iron ore having an alkali oxide (K2O + Na2O) content of 0.1% or more. Of course, phosphorus, zinc and alkali oxides may be contained in more than one iron ore.

The carbonaceous material containing carbon is crushed by the second crusher 12 and stored in the carbonaceous material hopper 30. Here, the carbon material may be a mixture of one or more of the coal-containing dust generated in the coal and steel processes. At this time, the carbon material is preferably limited to the particle size less than 0.1mm in order to improve the reactivity.

In addition, the subsidiary hopper 40 stores the basicity adjusting subsidiary materials and alkali oxide content adjusting subsidiary materials together or separately and separately. For example, CaO is used as the basic ingredient for controlling the basicity, and Na 2 CO 3 and K 2 CO 3 are used as the auxiliary raw materials for adjusting the alkali oxide content.

If iron ore, carbonaceous material and subsidiary materials are prepared in this way, each is weighed, charged in the mixer 50, and mixed to form a mixture.

At this time, the mixture preferably contains phosphorus (P): 0.06% or more, zinc (Zn): 0.02% or more and alkali oxides (K2O + Na2O): 0.1% or more, depending on the components of iron ore and carbonaceous material. However, it is preferable to maintain the compacted light in a high base group and a high alkali state in order to sufficiently separate phosphorus upon reduction of the compacted light described below. Accordingly, while adjusting the basicity (CaO / SiO 2) of the mixture to 1 or more, it is preferable to mix CaO, Na 2 CO 3 and K 2 CO 3 in an appropriate amount in order to adjust the content of the alkali oxide to be 0.5% or more. The reason for limiting the content of basicity and alkali oxide will be described later with reference to FIGS. 2 and 3.

If the mixture with the above conditions is formed, the mixture is put into the first molding machine 61 to be molded into a compact size of compacted light.

Subsequently, the compacted compacted light is charged into an open reduction furnace 70 to separate phosphorous, zinc and alkali elements contained in the compacted light while reducing iron (Fe) in the compacted light under an oxidizing atmosphere. Here, oxidizing atmosphere means exposure to the atmosphere without additional atmosphere control.

In detail, the iron oxide in the compacted ore is reacted (reduced) with carbon in the compacted ore as shown in Chemical Formula 1 below to generate iron (Fe) and CO. At this time, the generated CO is reacted (reduced) with the iron oxide in the compacted light as shown in Formula 2 below to generate iron (Fe) and CO 2. On the other hand, the generated CO 2 may be converted to CO by reacting with the carbon in the compacted light. In this way, the CO gas and the CO 2 gas generated by the reaction of iron oxide and carbon in the compacted light are discharged to the outside of the compacted light to form a gas film while surrounding the vicinity of the compacted light. As the gas film serves to block the oxidative atmosphere and the compacted light in the open reduction furnace 70, the compacted light is smoothly reduced in the open reduction furnace 70.

In this case, it is preferable that sufficient carbon is contained in the compacted light in order to sufficiently react the iron oxide and the carbon in the compacted light to sufficiently form the gas film. Accordingly, in the present embodiment, it is preferable to limit the content of the carbonaceous material to 10 parts by weight or more based on 100 parts by weight of the total mixture.

In addition, in order to reduce the compacted light in the open type reducing furnace 70 of the compacted light, it is preferable to maintain the firing temperature in the open type reducing furnace 70 at 1000 ° C or more.

4 is a graph showing the relationship between the metallization rate of the compacted light according to the temperature in the open reduction furnace and the mixing amount of the carbonaceous material, it can be confirmed that the compacted light containing 10 parts by weight or more of the carbonized material is smoothly at 1000 ℃ or more.

In addition, the maximum value of the reduction time of the compacted light is preferably limited until the carbon in the compacted light is completely consumed because carbon in the compacted light must react to form a gas film.

While the compacted light is reduced in the open reduction furnace 70, phosphorus (P) contained in the compacted light reacts with oxygen (O) and CaO in the compacted light and is trapped in slag in the form of CaO. (P 2 O 5). . Therefore, the compacted mineral is mixed with reduced iron and slag.

In addition, zinc contained in the compacted light, that is, zinc oxide and alkali oxide (K 2 O + Na 2 O) is first reduced at a lower temperature than iron oxide and is discharged together with the exhaust gas.

At this time, the vaporized zinc (Zn) generated during the reduction of the compacted light is discharged together with the exhaust gas to produce zinc oxide (ZnO) by the reaction of oxygen in the exhaust gas, the zinc oxide (ZnO) is contained in the dust by the collector 90 Is collected.

In addition, the vaporized alkali element generated upon reduction of the compacted light is discharged together with the exhaust gas to react with oxygen in the exhaust gas to produce an alkali acid product, and the alkali oxide is also included in the dust and collected by the collector 90.

The dust collected in the collector 90 is crushed in the crusher 100 to recover the crude zinc oxide and the alkali-containing wastewater.

On the other hand, the compacted iron mixed with reduced iron and slag is crushed in the third crusher 13, and separated by magnetic force in the magnetic separator 80 to separate the reduced iron and slag. Thus, the separated reduced iron is again formed into a briquette of a constant size in the second molding machine 62, and the slag with high CaO and phosphorus content is recycled as a fertilizer raw material.

EXAMPLE

The present invention will be described using the following examples.

Table 1 shows the chemical composition of each iron ore used in the experiment.

Iron ores with high phosphorus, zinc and alkali (Na 2 O, K 2 O) contents were used, and briquettes with high phosphorus, zinc and alkali contents were prepared by mixing the iron ores. In addition, to increase the zinc, phosphorus and alkali content to the maximum, reagent grade zinc oxide, phosphate and alkali oxides were added.

In addition, as a comparative example, as shown in Table 1, the chemical composition of iron ore (iron ore C) generally used in the iron making process was simultaneously shown. As shown in Table 1, iron ore C generally used in the iron making process is usually about 0.06% or less for phosphorus, about 0.02% or less for zinc and 0.03% or less for alkali oxides, but for iron ore A and iron ore B. It can be seen that phosphorus, zinc and alkali oxides are relatively high.

Table 1 division T.Fe SiO2 Al2O3 CaO MgO P Zn K2O Na2O Iron Ore A 41.1 17.8 2.41 3.20 13.7 0.013 0.103 0.687 - Iron Ore B 55.3 8.5 0.90 4.38 0.21 0.52 0.019 0.039 0.10 Iron Ore C 65.7 1.87 1.19 0.01 0.09 0.023 0.009 0.036 0.012

The iron ore A and iron ore B was mixed with coal (20% by weight) to prepare a briquette at the same time, and when adjusting the basicity (CaO / SiO 2) and alkali oxide content, reagent grade CaO, K 2 O, and Na 2 O were added. And the briquette reduction experiment was performed on reduction furnace simulation conditions.

The experiment was completed after maintaining the reduction temperature at 1200 ℃, the heating rate at 50 ℃ / min and the reducing temperature for 20 minutes in an inert gas atmosphere, and analyzed Fe, Zn, P in the briquette and Fe, Zn, P, K, Na in the slag. Was carried out.

Figure 2 is a graph showing the relationship between the phosphorus yield in the slag according to the basicity after reducing the compacted light at 1200 ℃ for 20 minutes, Figure 3 is according to the alkali oxide content in the compacted light after reducing the compacted light having a basicity of 20 minutes at 1200 ℃ It is a graph showing the relationship between the yield rate in slag.

As can be seen in Figure 2 it can be seen that with increasing the basicity, the yield of slag is slightly increased. Phosphorus oxide (P 2 O 5) is stabilized as an oxide under conditions of high base, and in particular, it is known that the phosphorus in the slag is stabilized even when a small amount of a strong base oxide such as alkali oxide is added. Therefore, in order to prevent the phosphate from being reduced in the reduction process of the iron oxide to be dissolved in the metal Fe and to remain in the slag, it can be seen that the addition of a small amount of the high base and the slag and the alkali oxide is effective.

And, the reduction rate of the briquettes after the experiment was about 85 ~ 90% level without being affected by the basicity. In addition, it can be seen that the zinc content in the slag after reduction is reduced from the initial 0.1% to about 0.004% level. In the case of zinc oxide, it was reduced at a lower temperature than iron oxide to form metal Zn. In the case of zinc, it was confirmed that it was vaporized into Zn in the gaseous phase at the same time as reduction, and reoxidized in exhaust gas and discharged to ZnO.

On the other hand, as can be seen in Figure 3 it can be seen that the increase in the yield of slag at the same time as the alkali oxide content in the briquettes increases. Therefore, it can be seen that it is advantageous to improve the yield recovery in slag when a mixture of ore having a high alkali oxide content and a high phosphorus content is used. Therefore, when the basicity (CaO / SiO 2) of the mixture was adjusted to 1 or more, the content of alkali oxides was adjusted to 0.5% or more, and it was confirmed that phosphorus could be recovered at a desired level or more.

Although the invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the invention is not limited thereto, but is defined by the claims that follow. Accordingly, one of ordinary skill in the art may variously modify and modify the present invention without departing from the spirit of the following claims.

[Description of the code]

11, 12, 13: Crushers 21, 22, 23: raw material hopper

30: charcoal hopper 40: side material hopper

50: mixer 61, 62: molding machine

70: open reduction furnace 80: magnetic separator

90: collector 100: crusher

Claims (18)

Mixing the iron raw material containing phosphorus, zinc and alkali oxides and carbonaceous material to form a mixture; Shaping the mixture into compacted light; Separating phosphorous, zinc and alkali elements contained in the compacted light while reducing the compacted light in an open reduction furnace; Crushing the reduced product of the compacted ore into a slag including reduced iron and phosphorus; The separated reduced iron is compacted, and the slag is reduced manufacturing method comprising the step of recovering. The method according to claim 1, In the step of forming the mixture, The method for producing reduced iron, wherein the mixture contains at least 0.06% of phosphorus (P), at least 0.02% of zinc (Zn) and at least 0.1% of alkali oxides (K 2 O + Na 2 O). The method according to claim 2, In the step of forming the mixture, The iron raw material is iron ore with a phosphorus (P) content of 0.06% or more, iron ore with a zinc (Zn) content of 0.02% or more and a reduced iron ore among iron ores having an alkali oxide (K2O + Na2O) content of 0.1% or more is mixed . The method according to claim 1, In the step of forming the mixture, The carbonaceous material is reduced iron manufacturing method is mixed with one or more of the coal-containing dust generated in the coal and steel process. The method according to claim 1, In the step of forming the mixture, The mixture has a basic iron (CaO / SiO 2) is at least 1 reduced iron manufacturing method. The method according to claim 1, In the step of forming the mixture, The mixture is reduced iron production method is adjusted so that the content of the alkali oxide is 0.5% or more. The method according to claim 5 or 6, In the step of forming the mixture, The mixture is further mixed with subsidiary materials for adjusting the basicity and the content of alkali oxides, The secondary raw material is CaO is used for the basicity control, Na2CO3 and K2CO3 is used for the alkali oxide content control method. The method according to claim 1, The carbonaceous material is reduced iron 10 is mixed with respect to 100 parts by weight of the total mixture manufacturing method. The method according to claim 1, In the step of reducing the compacted light in an open reduction furnace, Inside the reduction furnace is maintained an oxidizing atmosphere, And reducing the oxidized atmosphere and the lumped light by forming a gas film while surrounding the circumference of the lumped light. The method according to claim 9, In the step of reducing the compacted light in an open reduction furnace, The firing temperature of the compacted light is 1000 ℃ or more, The reduced iron production time of the reduced value is limited to until the carbon (C) in the compacted mineral is completely consumed. The method according to claim 1, In the step of reducing the compacted light in an open reduction furnace, The zinc (Zn) contained in the compacted ore in the reducing furnace is recovered as a dust in the exhaust gas in the gas phase, and the recovered iron dust is further recovered by zinc oxide (ZnO) to recover the separated process. The method according to claim 11, The vaporized zinc (Zn) generated during the reduction of the compacted light in the reduction furnace is discharged together with the exhaust gas, the zinc oxide (ZnO) is generated by the reaction of the vaporized zinc (Zn) and oxygen in the exhaust gas, the zinc oxide (ZnO) ) Is a method for producing reduced iron contained in the dust. The method according to claim 11, Alkali element is separated and recovered together with water during the recovery of the recovered dust dust. The method according to claim 1, In the step of separating into reduced iron and slag, The reduced iron and slag is reduced iron manufacturing method that is separated by a magnetic separator. A method for producing reduced iron, in which iron raw material and carbonaceous material are mixed to form a compacted ore, and then the compacted ore is reduced in an open reduction furnace to produce reduced iron. The method according to claim 15, The carbonaceous material is mixed with 10 parts by weight or more based on 100 parts by weight of the total compacted light, And reducing the oxidized atmosphere and the lumped light in the open reduction furnace by forming a gas film while the gas generated by the reduction of the lumped light by the carbon in the lumped light is enclosed. An apparatus for producing reduced iron, A plurality of raw material hoppers storing different kinds of iron ore; A carbon material hopper in which carbon material is stored; A mixer which forms a mixture by mixing different kinds of iron ore and carbon material ejected from the raw material hopper and the carbon material hopper; A first molding machine for molding the mixture into compacted light; An open reduction furnace of an oxidative atmosphere for reducing the compacted light; A crusher for crushing the reduced product reduced in the reduction furnace; A magnetic separator for separating the pulverized reducing product into reduced iron and slag by magnetic force; Reduced iron manufacturing apparatus comprising a second molding machine for molding the reduced iron. The method according to claim 17, A collector for collecting dust in the exhaust gas exhausted from the reduction furnace; The reduced iron manufacturing apparatus further comprises a crusher for separating the zinc oxide (Zn) and the alkaline element-containing waste water by crushing the dust collected in the collector.

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