JP2001226720A - Reducing agent and metal melting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal melting equipment having a vertical type metal melting furnace 1 which is charged with metallic raw materials Mc together with additives S from a charging port 5 in the upper part of a furnace casing 2, is supplied with combustible powder and granular materials Pb together with oxygen supply gas A from tuyeres 6 in the lower part of the furnace casing 2, melts the metallic raw materials Mc by the combustion heat in the furnace, discharging combustion discharge gas from a furnace top section 3 and discharges molten metal Mm from a furnace bottom section 9 and to provide a reducing agent which is supplied into this vertical type metal melting furnace 1, is capable of facilitating the recovery of useful metal by enhancing the content of the useful metal in dust D and is capable of making the resource recovery of waste plastics by saving the fuel to be supplied into the furnace. SOLUTION: A combustible powder and granular material Pb is formed as the reducing agent by kneading and mixing the dust D from the vertical type metal melting furnace 1 and the valuable metal-containing dust from another steel making furnace or both thereof and a waste plastic crushed material Pd and the vertical type metal melting furnace 1 is provided with a reducing agent supply means 23 constituted so as to supply the combustible powder and granular material Pb to the tuyeres 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reducing agent and a metal melting facility used for melting metal, and more particularly, to melting a metal raw material in a vertical metal melting furnace under a reducing atmosphere. In order to melt in the furnace, a reducing agent provided to maintain the inside of the furnace at a high temperature due to its own oxidizing heat, and a metal raw material together with an additive material through an inlet at the top of the furnace body are charged, and the blades at the bottom of the furnace body are charged. A vertical metal that supplies combustible powder granules together with an oxygen supply gas from the mouth, melts the metal raw material by the combustion heat in the furnace, discharges combustion exhaust gas from the furnace top, and discharges molten metal from the furnace bottom. The present invention relates to a metal melting facility comprising a melting furnace.

[0002]

2. Description of the Related Art Conventionally, in a metal melting facility, a cupola, which is usually a vertical melting furnace, is used as a melting furnace, and coke is used as a reducing agent together with metal raw materials including metal waste materials.
It was thrown in from a loading port provided above the cupola. Specifically, as shown in FIG. 4, the cupola is charged with metal raw material (hereinafter referred to as “metal”) Mc and coke K alternately from a charging port 5 provided in a furnace head 4 in an upper part of the furnace body 2. Then, a combustible powder Pb such as coke powder is supplied together with preheated air A1 as an oxygen supply gas A from a tuyere 6 provided at a lower portion of the furnace main body 2, and the base metal Mc is discharged by combustion heat of coke and the like in the furnace. It is configured to melt and discharge the combustion exhaust gas from the furnace top 3 and discharge the molten metal Mm from the tapping part 10 provided in the furnace bottom 9. The entrance 5
And the furnace top 3 in a double-pipe structure, forming a heat exchanger 12 for preheating the air supplied by the forced air blower 13 and supplying the preheated air A1 to the tuyere 6. . A duct for guiding the flue gas from the furnace top 3 toward the chimney 17 is provided to form an exhaust passage 11, in which a cooling tower 14 for cooling the flue gas from the cupola 1A, A dust collecting device 15 for collecting dust D accompanying the combustion exhaust gas cooled in the tower 14 and an induction blower 16 for sending the exhaust gas after dust removal by the dust collecting device 15 to a chimney 17 are sequentially provided.

As shown in FIG. 5, a layer of bed coke K1 is formed in the lower part of the furnace of the cupola 1A, and the base metal Mc charged alternately on the bed coke K1.
And the additional coke K2 form alternately stacked pre-tropical zones Zp. The tuyere 6 is located below the bed coke K1, and by the flow of the preheating air A1 supplied through the wind box 7, the preheating air A1 from the tuyere 6 causes the bed coke K1 to form a reducing atmosphere. Burns while forming. The combustion gas burned by the bed coke K1 rises, the vicinity of the upper end of the bed coke K1 reaches the melting temperature of the base metal Mc, and forms a melting zone Zm for melting the base metal Mc. The components of the combustion gas up to the melting zone Zm are mainly nitrogen and carbon monoxide. A region from the tuyere 6 to the melting zone Zm forms a supertropical zone Zs in which the bed coke K1 and the base metal Mc are melted and the molten metal Mm flowing down is heated. The molten metal Mm in which the base metal Mc is melted in the melting zone Zm flows down through the gap of the bed coke K1 forming the supertropical zone Zs, and forms a pool in the pool zone Zd of the furnace bottom 9.
The combustion gas rising along the gap in the furnace is the pre-tropical Z
p, the combustion is completed, and the heat exchanger 12
And flows out to the exhaust path 11. The melting zone Zm
At the same time as the metal Mc melts, the bed coke K
1 also burns to reduce the volume, and the metal Mc and the additional coke K2 of the pre-tropical zone Zp fall. Thus, the bed coke K1 maintains a substantially constant height. Further, the carbonaceous powder Pc made of coke powder supplied to the nozzle 24 provided in the tuyere 6 is blown into the furnace together with the preheated air A1, and the carbonaceous powder Pc is burned together with the bed coke K1. To maintain the furnace temperature. The molten metal Mm collected in the pool Zd is opened by opening a tap hole of a tapping section 10 provided in the furnace bottom 9 and flows out, and is taken out into a melting pot.

[0004]

However, even in the above-mentioned conventional metal melting equipment, it is an issue to prevent environmental pollution. In order to prevent dust from being discharged together with combustion exhaust gas and scattered into the atmosphere, Dust collector 1 as described above
5, dust D collected by the dust collector 15 contains a large amount of useful metal oxides such as iron, zinc, and lead. When dumping the collected dust D as waste, zinc and lead may be leached as harmful substances. As a result, the burden on the environmental conservation of waste treatment increases. These problems are common not only to steel melting equipment but also to copper or copper alloy melting equipment. Incidentally, the content of the useful metal oxide in the collected dust in the steel melting facility is, for example, 10 to 20% for zinc oxide and 20 to 30% for iron oxide in terms of ferrous oxide. .

[0005] The concentration of the above-mentioned useful metals is too low to be recovered from the collected dust, for example, in the case of zinc, in the case of reduced melting recovery, and the recovery cost is too high. As a means for solving this point, it has been proposed to recycle the collected dust to a melting furnace and concentrate it until the content of zinc oxide in the dust can be recovered (for example, Japanese Patent Application Laid-Open No. 55-12).
No. 5211, JP-A-2-2630088). The proposal described in Japanese Patent Application Laid-Open No. 55-125211 discloses a method in which recovered dust is kneaded and granulated together with a carbonaceous powder such as coke powder as interior charcoal to form pellets or briquettes, and this is mixed with a metal raw material in a vertical direction such as cupola. It is charged into the mold melting furnace from the charging inlet. However, in this case, the pellets or briquettes collapse along with the volatilization and scattering of carbonaceous powders and metals before reaching the bottom of the furnace, closing gaps between the pellets or briquettes, causing an abnormal increase in furnace pressure. There is a problem that it may occur. For the same reason, it is not possible to use a material that softens or melts at a relatively low temperature. Further, since carbonaceous powder such as coke is used to reduce useful metal oxides in the collected dust, there is still room for improvement in consuming fuel resources. Japanese Patent Application Laid-Open No. 2-263088 discloses that collected dust is repeatedly introduced into a cupola by blowing it from a lance or the like, and the collected dust is reduced in a reduction zone in a furnace. is there. This proposal suggests that if the collected dust is fine powder and the combustible powder (for example, unburned carbon content) is contained in the collected dust to a certain degree or more, this may explosively burn in the furnace. However, since combustion control is not easy, it is not considered to be a sufficient improvement.

On the other hand, the environmental burden of waste such as municipal waste and industrial waste has been increasing, and it has become necessary to recycle waste. In addition, waste plastics have a difficulty in incineration at the time of disposal. This is due to the fact that the amount of heat generated by combustion during the incineration treatment is high. In other words, if garbage with a high water content and a low calorific value is mixed with waste plastic with a low calorific value and a high temperature, it will hinder stable combustion in the furnace and hinder stable control of the incinerator. is there. As a means to solve this problem, the target is limited to waste plastics that do not generate harmful gases (specifically, expanded polystyrene, which is industrial waste plastic), but it is not halogen-substituted and has a coarse powder state. It has been proposed to introduce a plastic powder made of waste plastic into a tuyere of a cupola using a lance (for example, JP-A-9-170881). This can be evaluated as saving fuel resources and recycling waste by using waste plastic in a coarse powder state instead of carbonaceous powder blown from tuyeres. However, industrial waste plastics have a high gasification rate and therefore a high combustion rate. Also, the bulk density is low. For this reason, it is not easy to rise to the furnace top side with the combustion gas and reach the vicinity of the molten metal and burn it, and there is a problem that the temperature of the molten metal may be lowered.

Therefore, the present invention solves the above-mentioned problems, and makes it possible to increase the content of useful metals in the collected dust and recover the same, and to save fuel supplied to the furnace. It is another object of the present invention to provide a reducing agent and a metal melting facility capable of turning waste into a fuel resource.

[0008]

[Means for Solving the Problems]

[Characteristics of the present invention] The reducing agent according to the present invention is characterized in that crushed waste plastic is granulated together with dust, and each has the following characteristics. .

[0010] The first of the reducing agent of the present invention for the above purpose.
As a feature of the present invention, as described in claim 1, kneading of dust discharged from a vertical metal melting furnace or dust containing valuable metals discharged from another steelmaking furnace, or both, and waste plastic crushed material as components. It consists in the formed granular material.

The second aspect of the reducing agent of the present invention for the above purpose is as follows.
A characteristic configuration is that the first reducing agent has a first characteristic.
The characteristic feature is that the granular material is formed by removing chlorine in the waste plastic by a heat treatment.

Further, the metal melting equipment according to the present invention is characterized in that it has the above-mentioned means for supplying a reducing agent according to the present invention, and each has the following characteristics.

[0013] A first characteristic configuration of the metal melting equipment of the present invention for the above object is as described in claim 3, wherein the tuyere is provided with the first characteristic configuration or the second characteristic configuration as combustible powder particles. The point is that a reducing agent supply means configured to supply the reducing agent is provided.

According to a second aspect of the present invention, the vertical metal melting furnace according to the first aspect of the present invention melts an iron material. In that it is a cupola.

[Operation and Effect of Characteristic Constitution] The reducing agent according to the present invention can provide the reducing agent to the heating of the molten metal without any trouble by granulating the crushed waste plastic with dust. Waste plastic can be recycled as resources, and the amount of landfill at the waste disposal site can be reduced. Each of them has the following unique effects.

According to the first characteristic configuration of the reducing agent according to the present invention, since the granular material is supplied as a reducing agent into the furnace including the waste plastic, it can be replaced with a powdery carbonaceous material as in the prior art. Can be used. Therefore, waste plastic can be used as fuel resources, and fuel resources can be saved.
Furthermore, since the granular material contains the useful metal once discharged as dust and is supplied again into the furnace, the useful metal can be concentrated. In addition, the reducing agent formed by kneading waste plastic having a low bulk density together with dust into a granular material has a bulk density suitable for blowing into the furnace from the tuyere, and floats due to the rising airflow in the furnace. Without reaching the molten metal and burning. In addition, since waste plastics can be incinerated at the same time, the amount of waste discarded at waste disposal sites can be reduced. In addition, by using a hydrocarbon-based substance instead of conventional coke powder, the amount of carbon dioxide generated per calorific value can also be reduced, so the amount of carbon dioxide in the exhaust gas can be reduced, contributing to global environmental conservation. . Further, since the dust and the waste plastic are kneaded to form the granular material, it is easy to adjust the compounding ratio appropriately to adjust the bulk density to be suitable for blowing into the furnace.

According to the second aspect of the reducing agent according to the present invention, the plastics in which the waste plastic is chlorine-substituted, for example, vinyl chloride, while exhibiting the function and effect of the first aspect of the reducing agent. Even so, it is possible to prevent the metal melting furnace from being damaged and to prevent the generation of dioxins in the exhaust gas from the metal melting furnace.

Since the metal melting equipment according to the present invention is configured to supply the reducing agent according to the present invention into a furnace, the reducing agent contains a useful metal and is contained in the collected dust. It is capable of concentrating useful metals and has the following unique effects.

According to the first characteristic configuration of the metal melting equipment according to the present invention, the function and effect of the reducing agent can be realized.
That is, since the reducing agent supply means is provided in the tuyere so that the reducing agent according to the present invention can be supplied into the furnace from the tuyere, the reducing agent reliably reaches the vicinity of the molten metal. It is possible to incinerate waste plastic at the same time as melting the metal, and because it burns in a reducing atmosphere, even if the combustion gas contains chlorine, it can reduce dioxins. In addition to being able to suppress generation,
Since the carbon content of the combustible gas of the reducing agent is low and the amount of carbon dioxide emitted can be reduced, it can also contribute to global environmental conservation.

According to the second aspect of the metal melting facility according to the present invention, the structure of the metal melting furnace is simple while the operation and effect of the first aspect of the metal melting facility are obtained. Since the metal to be formed is iron, the iron oxide in the collected dust can be reduced in the furnace without being concentrated and returned to the material.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the above-mentioned reducing agent and metal melting equipment of the present invention will be described below with reference to the drawings. Note that the same elements as those described in the related art and elements having the same functions are denoted by the same reference numerals as those in FIGS.
A part of the detailed description is omitted.

As shown in FIG. 1, the metal melting facility according to the present invention includes a cupola 1A as a vertical metal melting furnace 1, and the cupola 1A is supplied from a charging port 5 of a furnace head 4 to a metal raw material (metal). Mc is charged together with an additive material S such as a slag adjusting material, and combustible powder particles Pb are supplied from a tuyere 6 of a furnace bottom 9 together with preheated air A1 as an oxygen supply gas A, and The base metal Mc is melted by the combustion heat, and the combustion exhaust gas is discharged from the furnace top 3 and the molten metal Mm is discharged from the furnace bottom 9. A reducing agent supply means 2 configured to be able to supply the tuyere 6 with a particulate material Pm, which is a reducing agent described later, as the combustible powder material Pb.
3 is provided. This cupola 1A is mainly for charging and melting waste iron materials and raw iron materials as base metal Mc.

When melting the base metal Mc in the cupola 1A, the reducing agent serves to maintain the inside of the furnace at a high temperature by its own oxidizing heat in order to melt the base metal Mc in a reducing atmosphere. It also fulfills. This reducing agent
The dust P discharged from the cupola 1A and the crushed waste plastic Pd are kneaded and formed as components to form the granular material P.
m. As shown in FIG. 2, for example, as shown in FIG. 2, the crushed waste plastic Pd and the dust D collected by the dust collecting device 15 provided in the exhaust path 11 are charged into the hopper 20 of the kneading and shaping machine 19. The crushed waste plastic Pd is extruded from the extrusion nozzle 22a of the extruded cylinder 22 while being kneaded by the kneading screw 21 at a temperature at which the crushed waste plastic Pd partially melts. The extruding cylinder portion 22 of the kneading molding machine 19 by the kneading screw 21 is heated from the outside using a hot gas and is heated to about 120 to 250 ° C. The waste plastic crushed material Pd and the dust D mixed by the kneading screw 21 in the hopper 20 are sufficiently kneaded, and the kneaded material pushed into the extruded cylindrical portion 22 heated in this way is the extruded cylinder. Before being extruded from the extrusion nozzle 22a provided at the tip of the portion 22, the waste plastic crushed material Pd is softened and partially melted, and is fused to each other with the dust D interposed therebetween to form a rod. Molded into A cutting tool (not shown) is provided at the tip of the extrusion nozzle 22a, and the rod-shaped compact extruded from the extrusion nozzle 22a is cut to form a granular material Pm.

The crushed waste plastic Pd is obtained by crushing the collected waste plastic with a crusher 18. Any type of crusher 18 can be used, and is selected according to the properties of the collected waste plastic. If the waste plastic crushed material Pd is obtained by crushing ordinary industrial waste plastic mainly composed of ordinary expanded polystyrene, the kneading molding machine 19 is used.
May be relatively low, the temperature of the hot gas is maintained at 150 to 200 ° C,
The granular material Pm is formed under a heating temperature of about a degree. When the waste plastic crushed material Pd is obtained by crushing a chlorine-containing plastic such as polyvinyl chloride, the chlorine contained is removed by thermal decomposition. Therefore, the heating temperature in the kneading molding machine 19 is high, the temperature of the hot gas is maintained at 220 to 300 ° C., and the granular material Pm is molded at a temperature of about 200 to 280 ° C. When the waste plastic crushed material Pd mixed with the dust D is press-formed in the kneading molding machine 19 in the state of being heated in this way, the polyvinyl chloride constituting the waste plastic crushed material Pd is thermally decomposed. It releases chlorine. As a result, the formed granular material Pm is one from which chlorine has been removed, and even if this is supplied to the cupola 1A together with the preheated air A1 from the tuyere 6, it does not cause an obstacle such as corrosion to the metal melting equipment. Further, generation of dioxins in the combustion gas can be prevented. In FIG. 2, a mechanism for collecting released chlorine is not shown.

The tuyere 6 is provided with a reducing agent supply means 23 in order to supply the reducing agent formed on the granular material Pm into the furnace. This reducing agent supply means 23 is provided with a lance 25 in the tuyere tube 8 as shown in FIG.
In addition, it is configured to supply the granular material Pm. The lance 25 is connected to a reducing agent supply pipe 26 from a screw feeder 27 constituting the reducing agent supply means 23,
The granular material Pm is supplied to the lance 25 by the screw feeder 27. The tuyere 6 is connected to the tuyere tube 8
And the lance 25, and the granular material Pm supplied to the lance 25 is sucked and ejected into the furnace together with the tuyere air as the preheated air A1 is blown into the furnace. Can supply. In such a configuration, the granular material Pm
Is heat-molded, compacted, and molded with dust D, so that the bulk density is appropriately increased, so that when the waste plastic is a foamed resin such as industrial waste plastic, Also easily reaches the pool of molten metal Mm together with the blown tuyere air and does not easily float by the rising air current, so that it reaches near the surface of the pool and the pool Zd. The combustion in the space described above certainly contributes to the maintenance of the temperature of the pool.

The reducing agent and metal melting equipment described above are:
It is used as follows. Furnace top 3 of Cupola 1A
The dust D collected by the dust collecting device 15 provided in the exhaust path 11 connected to the exhaust pipe 11 is collected, while the waste plastic is crushed to form the waste plastic crushed material Pd, and the dust D and the waste plastic crushed material Pd are collected. Is supplied to the reducing agent supply means 23 connected to the tuyere 6 by heating and kneading with a kneading / molding machine 19 to form the granular material Pm. Since the granular material Pm is formed mainly of plastic having a low calorific value, it emits high heat and burns when exposed to a high temperature in a furnace. The waste plastic in the granular material Pm molded while being heated by the kneading molding machine 19 is mainly composed of polystyrene (expanded polystyrene or the like) if it is derived from industrial waste plastic, and therefore contains chlorine. In the case of a chlorine-substituted plastic (polyvinyl chloride or the like), the chlorine is dissociated from the waste plastic by thermal decomposition in the kneading and molding machine 19, and the granular material Pm does not contain chlorine. It is formed integrally with the dust D in a state where the plastic is fused.

As described above, the reducing agent supply means 23
Dust D returned to the furnace as the granular material Pm from
The metal oxides contained therein are once reduced in the furnace, and the iron oxide from which the base metal Mc is evaporated and oxidized is returned to the molten metal Mm in the furnace again, and oxides of useful metals such as zinc and lead are produced. Is reduced and evaporated again, flows out into the exhaust path 11 together with the combustion exhaust gas discharged from the furnace top 3, and is collected again by the dust collecting device 15. The oxide of the useful metal is gradually concentrated in the dust D. The dust D in which the useful metal is concentrated is partially separated at the place where the dust D is taken out from the dust collector 15 and sent to the useful metal recovery process. As described above, since waste plastic is formed into a granular material Pm without containing chlorine, there is no danger of generating dioxin even if the waste plastic is incinerated. Furthermore, since the combustibles in the granular material Pm supplied as the reducing agent are formed of hydrocarbons, unlike the conventionally used coke powder, the generated combustion exhaust gas contains a large amount of water vapor. Since the content of carbon dioxide is lower than before, the adverse effect on global warming can be suppressed.

As described above, using the reducing agent according to the present invention,
Alternatively, by using the metal melting equipment according to the present invention configured to be able to use the reducing agent, it is possible to increase the content of the useful metal in the collected dust and to collect the useful metal, and furthermore, to supply the metal to the furnace. Waste can be turned into a fuel resource while saving fuel.

[Another Embodiment] An embodiment of a reducing agent according to the present invention not shown in the above embodiment and a metal melting facility using the reducing agent will be described below.

<1> In the above embodiment, the vertical metal melting furnace 1 is a cupola 1A, and the cupola 1A is mainly used for charging and melting waste iron and raw iron as base metal Mc. An example was explained, but the bullion Mc
May be copper or another non-ferrous metal, and in such a case, the same usefulness as described in the above embodiment is exhibited.

<2> In the above-described embodiment, the reducing agent is used to form the granular material P formed by kneading the dust D discharged from the cupola 1A and the crushed waste plastic Pd as components.
Although the example of forming with m has been described, the reducing agent mixes the dust D discharged from the cupola 1A with the dust containing valuable metal discharged from another steelmaking furnace, or wastes the dust containing valuable metal. It may be kneaded and formed together with the crushed plastic Pd to form the granular material Pm. In this way, useful metals in dust discharged from other steelmaking furnaces can be simultaneously recovered.

<3> In the above embodiment, an example was described in which the dust P discharged from the cupola 1A and the crushed waste plastic Pd were kneaded and formed as components to form the granular material Pm. In addition to the above, a carbonaceous powder such as coke may be mixed to form the granular material.

<4> In the above embodiment, an example was described in which the preheated air A1 was supplied from the tuyere 6 of the cupola 1A, but the oxygen supply gas A from the tuyere 6 was oxygen-enriched air. There may be.

<5> In the above embodiment, the example of the kneading and shaping machine 19 has been illustrated and described. However, the kneading and shaping machine is not limited to the illustrated type, and may be used after finely pulverizing waste plastic. A granulator for kneading and granulating by adding a binder or the like together with dust may be used. In this case, the binder may be water, but the binder is selected or heated after granulation to heat the plastics together so that they are not powdered and scattered when supplied into the tuyere tube. It is preferable to perform fusion.

<6> In the above-described embodiment, the reducing agent supply means 23 is connected to the lance 25 provided in the tuyere tube 8 from the screw feeder 27 via the reducing agent supply pipe 26 and the granular material P
Although the example in which m is supplied is illustrated and described, the reducing agent supply means is provided with an air flow conveying means instead of the screw feeder 27 so that the granular material is air flow conveyed through the reducing agent supply pipe. Alternatively, the reducing agent may be supplied to the tuyere using other means.

<7> In the above embodiment, the vertical metal melting furnace 1 is the cupola 1A, and the cupola 1A is mainly used for charging and melting the waste iron material or the raw material iron as the base metal Mc. Although an example has been described, the type of the vertical metal melting furnace 1 does not matter, and may be a shaft furnace or a vertical melting furnace of a type other than cupola. For example, when using a vertical melting furnace of another type, without charging coke, only the metal is charged, the metal only by the combustion heat of the reducing agent composed of the granular material supplied from the tuyere You may make it melt.

[0037]

As described above, according to the present invention,
It is possible to collect useful metals in the collected dust,
The waste was turned into a fuel resource and the fuel supplied to the furnace was saved.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing an example of a metal melting facility according to the present invention.

FIG. 2 is a configuration explanatory view showing an example of the kneading molding machine shown in FIG.

FIG. 3 is a longitudinal sectional view of a cupola-like portion showing a specific example of the reducing agent supply means shown in FIG. 1;

FIG. 4 is a structural explanatory view showing an example of a conventional metal melting facility.

FIG. 5 is a longitudinal sectional view of a main part of a cupola showing a state in a metal melting furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical metal melting furnace 2 Furnace main body 3 Furnace top 5 Charging inlet 6 Tuyere 9 Furnace bottom 23 Reducing agent supply means A Oxygen supply gas D Dust Mc Metal raw material Pb Combustible powder Pd Waste plastic crushed material Pm Granular material S Addition Lumber

Claims (4)

[Claims] 1. A metal raw material (M) in a vertical metal melting furnace (1).
c) melting the metal raw material (Mc) in a reducing atmosphere in order to maintain the inside of the furnace at a high temperature by oxidizing heat of itself in melting the metal raw material (Mc); Dust (D) discharged from melting furnace (1)
Or a reducing agent composed of granules (Pm) formed by kneading valuable metal-containing dust discharged from another steelmaking furnace or both of them and waste plastic crushed material (Pd) as components. 2. The reducing agent according to claim 1, wherein the granular material (Pm) is formed by removing chlorine in the waste plastic by a heat treatment. 3. A vertical metal melting furnace (1), and a metal raw material (Mc) is charged together with an additive (S) from a charging port (5) at an upper part of a furnace body (2), and the furnace body (2) is provided. Lower tuyere (6)
Supplies the combustible powder (Pb) together with the oxygen supply gas (A), melts the metal raw material (Mc) by the combustion heat in the furnace, and discharges the combustion exhaust gas from the furnace top (3).
A metal melting facility for discharging molten metal (Mm) from a furnace bottom (9), wherein the tuyere (6) is supplied with the reducing agent according to claim 1 or 2 as the combustible powder (Pb). A metal melting facility provided with a reducing agent supply means (23) configured so as to be possible. 4. The metal melting equipment according to claim 3, wherein the vertical metal melting furnace is a cupola for melting an iron material.