JP2011080127A - Zinc separation method and appliance for separating zinc - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a zinc separation method and an appliance for separating zinc which separate zinc from iron material having deposited zinc while preventing oxidation of iron material part of the iron material having deposited zinc although there is an oxidizing atmosphere in a furnace. <P>SOLUTION: Galvanized steel sheet scraps 1, 1, ... and calcined cokes 2, 2, ... are stored in a basket 11 with an opening part 11a formed therein, at the same time, a barrier layer 3 made of the calcined cokes 2 is formed between the galvanized steel sheet scraps 1, 1, ... and the opening part 11a, the basket 11 is arranged in a heating furnace 100 of the oxidizing atmosphere, the temperature in the heating furnace 100 is raised to 1,050°C and, thereby, zinc is vaporized from the galvanized steel sheet scraps 1, 1, .... <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technique for separating zinc adhering to the surface of an iron material.

  Conventionally, galvanized steel sheet waste is recycled as a raw material for casting (cast iron melting material) by remelting the scraps (hereinafter referred to as “galvanized steel sheet scraps”) remaining after cutting out members of a predetermined shape from galvanized steel sheets. To be done.

  Examples of the method for remelting the galvanized steel sheet include a method using a cupola (Cupola furnace), a method using an electric furnace such as an induction heating furnace, and the like.

A cupola is a type of shaft-type melting furnace that melts galvanized steel sheet scraps with heat generated by burning coke (Koks (Germany), coke (UK)).
Cupola is difficult to adjust the amount of molten metal generated by melting galvanized steel plate scraps, and the amount of carbon dioxide generated in the process of melting galvanized steel plate scraps is large, so the burden on the environment is large. There are problems such as.

When melting galvanized steel plate scraps as they are in an electric furnace, the electric furnace is usually sealed, so that zinc evaporated inside the electric furnace penetrates into the furnace wall (refractory) of the electric furnace and damages the furnace wall. In addition, zinc adhering to the surface of the galvanized steel sheet scraps is mixed into the molten metal, which raises the problem that the zinc concentration in the molten metal increases, and as a result, the quality of the casting material decreases.
Therefore, zinc is separated (removed) from the surface of the galvanized steel plate scrap in advance, and the galvanized steel plate scrap after the zinc is separated is melted in an electric furnace.

  As a method of separating zinc from the surface of the galvanized steel plate scraps, (A) a method using a firing furnace capable of making the internal space a high vacuum (for example, containing the galvanized steel plate scraps inside the firing furnace, Method of evaporating zinc from the surface of the galvanized steel sheet by reducing the pressure inside the firing furnace to 0.0002 atmosphere and maintaining the temperature inside the firing furnace at 900 ° C.), (B) Induction heating type (For example, by containing galvanized steel plate scraps in the flat furnace and heating the galvanized steel plate scraps by induction heating to reduce the pressure inside the flat furnace to about 0.9 atm. And a method of evaporating zinc from the surface of the galvanized steel sheet scraps).

However, the above method (A) requires equipment (such as a decompression pump) and a strong structure for making the inside of the furnace in a high vacuum, so that equipment cost and installation space are increased.
In the above method (A), in order to make the inside of the furnace high vacuum, the galvanized steel plate scraps are housed in the inside of the furnace → the inside of the furnace is made high vacuum (reduced pressure) → the temperature inside the furnace is raised. It is premised on a batch-type operation that sequentially performs a series of operations of evaporating zinc → lowering the temperature inside the furnace to near room temperature → taking out zinc-plated steel sheet from which zinc has been separated to the outside of the furnace, This is not preferable from the viewpoint of improving energy efficiency and shortening cycle time (and thus improving productivity).
In particular, when the method (A) is applied to a furnace that is already installed in a factory that is a source of galvanized steel sheet scraps, the amount of galvanized steel sheet scraps generated in the factory may not be so large. Batch operation is not preferable from the viewpoint of operation cost.

  In the method (B), zinc fumes are generated inside the furnace. Therefore, it is necessary to remove the zinc fumes from the atmosphere inside the furnace before opening the furnace, but the zinc fumes are removed. The equipment (dust collector) for this becomes a large scale, and the equipment cost, the energy cost for operating the equipment, and the installation space increase.

  In addition to the above methods (A) and (B), a method for separating zinc from galvanized steel plate scraps, iron-making dust, and the like is disclosed. For example, it is as described in Patent Document 1 to Patent Document 7.

  The method described in Patent Document 1 is a method in which the entire interior of the furnace is filled with an atmosphere containing carbon monoxide and carbon dioxide, and the galvanized steel sheet waste housed in the furnace is heated to 800 ° C to 1200 ° C.

  In the method described in Patent Document 2, iron dust containing iron oxide, zinc oxide and the like is added to a reaction furnace together with coal and oxygen, and the temperature is raised to gasify the coal to generate carbon monoxide gas and hydrogen gas. In this method, iron oxide and zinc oxide are reduced by these gases, iron and zinc are separated by evaporating the reduced zinc into the gas, and the gas containing zinc is cooled.

  In the method described in Patent Document 3, the reaction is performed by alternately performing the operation of introducing high-temperature exhaust gas containing dust into the inside of a cylindrical reaction furnace extending in the vertical direction and the operation of inserting coke into the inside of the reaction furnace. A dust layer (reduction zone) and a coke layer (reduction atmosphere replenishment replenishment zone) are stacked in the vertical direction inside the furnace, and the reducing gas generated from the high-temperature exhaust gas and coke is placed above the reactor. In this method, the zinc contained in the dust layer is reduced by passing downward from the dust, and the zinc is evaporated and separated from the dust.

  In the method described in Patent Document 4, a mixture raw material mainly composed of iron oxide containing zinc and a carbonaceous material (reducing agent) is prepared, and the mixture raw material is charged into a rotary kiln furnace at 1100 ° C. or higher. Reducing gas (carbon monoxide) generated from the material reduces and evaporates zinc oxide in iron oxide containing zinc, and further contains iron that can be charged into a reduction furnace by reducing iron oxide with reducing gas It is a way to get things.

  In the method described in Patent Document 5, a carbonaceous reducing agent is added to a zinc-containing waste generated in the process of refining molten steel to produce stainless steel, and the mixture is heated inside the rotary hearth furnace. Thus, zinc is volatilized and removed to obtain a dezincified mixture.

  The method described in Patent Document 6 is a method in which zinc-containing iron oxide and a reducing agent are heat-treated in a reduction furnace to separate zinc from zinc-containing iron oxide and reduce iron oxide to obtain metallic iron. In this method, at least one of ASR, home appliance shredder dust, waste plastic, RDF, and RPF is supplied as a reducing agent, and the reduction temperature of the reduction furnace is 800 to 1080 ° C.

In any of the methods described in Patent Document 1 to Patent Document 6, it is possible to prevent oxidation of the iron material (or to enable reduction of iron oxide) and metal by filling the whole furnace with a reducing atmosphere. This is common in that zinc (unoxidized zinc) can be recovered.
However, the methods described in Patent Literature 1 to Patent Literature 6 all have a composition (component) in which the atmosphere in the furnace is different from the atmosphere, and therefore the furnace atmosphere is a kind of consumable. It is not preferable to release the atmosphere in the furnace to the atmosphere when opening the door.
In addition, depending on the type of atmosphere in the furnace (especially when the atmosphere in the furnace contains a large amount of carbon monoxide and carbon dioxide), the atmosphere in the furnace is also reduced from the viewpoint of environmental burden. It is not preferable to release it to the atmosphere.
Therefore, these methods are premised on batch operation, which is not preferable from the viewpoint of improving energy efficiency and shortening cycle time (and thus improving productivity).

The method described in Patent Document 7 is a method in which a metal member having zinc attached to the surface is placed in a furnace having substantially the same atmosphere as the atmosphere and atmospheric pressure, and heated at a temperature lower than the melting point of zinc. This is a method for recovering zinc powder by vaporizing zinc adhering to the surface of a member and forcibly cooling the vaporized zinc.
However, in the method described in Patent Document 7, since the inside of the furnace is substantially in an oxidizing atmosphere, the surface of the metal member is oxidized, and the yield of the metal member after collecting the zinc powder is reduced (the metal member The weight of the unoxidized part is reduced).

JP-A-5-125458 JP-A-9-53129 JP 2000-17346 A JP 2002-241850 A JP 2004-76152 A JP 2006-328451 A JP-A-6-108173

  The present invention provides a zinc separation method and a zinc separation tool capable of separating zinc from a zinc-adhered iron material while preventing oxidation of the iron material portion in the zinc-adhered iron material even in an oxidizing atmosphere inside the furnace.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1,
A zinc-adhered iron material and a carburizing agent are accommodated in a container in which an opening is formed, and a barrier layer made of the carburizing agent is formed between the zinc-adhered iron material and the opening accommodated in the container. A containment process,
The container containing the zinc-adhered iron material and the carburizing agent is disposed inside an oven in an oxidizing atmosphere, and the temperature inside the furnace is equal to or higher than the lower limit evaporation temperature of zinc adhering to the surface of the zinc-adhered iron material and An evaporation step of evaporating zinc from the zinc-adhered iron material by raising it to a treatment temperature that is a temperature that is less than the melting point of the iron part of the zinc-adhered iron material;
It comprises.

In claim 2,
In the housing step,
The carburizing agent is filled in a gap between the zinc-adhered iron materials accommodated in the container.

In claim 3,
In the housing step,
A lid formed with a vent hole communicating the inside and the outside of the container is fixed to the opening of the container, so that the additional iron is placed between the zinc-adhered iron material housed in the container and the lid. A barrier layer made of charcoal is placed.

In claim 4,
An opening is formed, a zinc-adhered iron material and a carburizing agent are accommodated therein, and a barrier layer made of the carburizing agent is formed between the zinc-adhered iron material accommodated in the interior and the opening. A container is provided.

In claim 5,
A lid is provided in which a vent hole is formed to communicate the inside and the outside of the container when fixed to the opening of the container.

In claim 6,
When the lid is fixed to the opening of the container, a barrier layer made of the carburizing agent is disposed between the zinc-adhered iron material housed in the container and the lid.

  The present invention has an effect that it is possible to separate zinc from a zinc-adhered iron material while preventing oxidation of the iron material portion in the zinc-adhered iron material even in an oxidizing atmosphere inside the furnace.

The plane sectional view showing the heating furnace to which one embodiment of the zinc separation method concerning the present invention is applied. The perspective view which shows one Embodiment of the instrument for zinc separation which concerns on this invention. Side surface sectional drawing which shows one Embodiment of the instrument for zinc separation which concerns on this invention. The flowchart which shows one Embodiment of the zinc separation method which concerns on this invention. The figure which shows the heat pattern of the heating furnace with which one Embodiment of the zinc separation method which concerns on this invention is applied. The figure which shows the change of the zinc concentration of a zinc treatment iron material.

Below, the heating furnace 100 is demonstrated using FIG.
The heating furnace 100 is a furnace applied to one embodiment of the zinc separation method according to the present invention, which will be described in detail later, and one embodiment of the zinc separation device according to the present invention (zinc separation device 10). The preheating unit 110, the heating unit 120, and the cooling unit 130 are provided.

The preheating unit 110 removes an object (in this embodiment, a zinc separating tool 10 containing galvanized steel plate scraps 1..., Described later, and calcine coke 2) from the room temperature. This is a part for preheating the object by gradually raising the temperature to the temperature.
The preheating unit 110 includes a furnace body 111, a transfer device 112, a plurality of burners 113, 113, and an entrance door 114.

  The furnace body 111 is a combination of a generally cylindrical (tunnel-shaped) structure constituting the preheating unit 110 and a refractory material covering the inner peripheral surface of the structure. Openings are formed at both ends of the furnace body 111.

The conveying device 112 is disposed inside the furnace body 111, and an object formed in the furnace body 111 is opened from the opening formed at one end of the furnace body 111 to the other end of the furnace body 111. It is an apparatus which conveys toward a part.
The transport device 112 of the present embodiment is a roller conveyor, but may be replaced with another type of device as long as the object can be moved inside the furnace body 111.

The plurality of burners 113, 113... Supplies heat for heating the atmosphere inside the furnace body 111, and consequently the object carried into the furnace body 111.
In this embodiment, a plurality of burners 113, 113... Are fixed to the side surface of the furnace body 111 at predetermined intervals along the conveyance direction of the object by the conveyance device 112.

The entrance door 114 is a door provided at an opening formed at one end of the furnace body 111.
By opening the entrance door 114, it is possible to carry an object into the furnace body 111 from the outside of the heating furnace 100 through an opening formed at one end of the furnace body 111.
By closing the entrance door 114, the gas inside the furnace body 111 is prevented from escaping to the outside of the furnace body 111 through an opening formed at one end of the furnace body 111, and the temperature inside the furnace body 111 is maintained. Is possible.

In this embodiment, among the plurality of burners 113, 113..., The heating power (the amount of heat supplied to the inside of the furnace body 111) is increased as the burner 113 is closer to the opening formed at the other end of the furnace body 111. Thus, the temperature of the atmosphere inside the furnace body 111 is gradually increased from one end of the furnace body 111 (the end where the entrance door 114 is provided) toward the other end.
Accordingly, the object carried into the furnace body 111 is gradually heated in the process of being transported from one end portion of the furnace body 111 toward the other end portion by the transport device 112.

The heating unit 120 is a part of the heating furnace 100 that heats an object to a predetermined temperature (holds the object at a predetermined temperature).
The heating unit 120 includes a furnace body 121, a transfer device 122, a plurality of burners 123, 123, and a first partition door 124.

The furnace body 121 is a combination of a generally cylindrical (tunnel-shaped) structure that forms the heating unit 120 and a refractory material that covers the inner peripheral surface of the structure. Openings are formed at both ends of the furnace body 121.
The opening formed at one end of the furnace body 121 is connected to the opening formed at the other end of the furnace body 111 of the preheating unit 110. Therefore, the interior of the furnace body 121 of the heating unit 120 communicates with the interior of the furnace body 111 of the preheating unit 110.

The transfer device 122 is disposed inside the furnace body 121, and an opening formed in the other end portion of the furnace body 121 from the opening formed in one end portion of the furnace body 121 for the object carried into the furnace body 121. It is an apparatus which conveys toward a part.
The transport device 122 of the present embodiment is a roller conveyor, but may be replaced with another type of device as long as the object can be moved inside the furnace body 121.

The plurality of burners 123, 123... Supply heat for heating the atmosphere inside the furnace body 121, and thus the object carried into the furnace body 121.
In the present embodiment, a plurality of burners 123, 123... Are fixed to the side surface of the furnace body 121 at predetermined intervals along the conveyance direction of the object by the conveyance device 122.

The first partition door 124 is a door provided at an opening formed at one end of the furnace body 121 (a communication portion between the interior of the furnace body 111 and the interior of the furnace body 121).
By opening the first partition door 124, it is possible to move the object from the inside of the furnace body 111 of the preheating unit 110 to the inside of the furnace body 121 of the heating unit 120.
By closing the first partition door 124, the gas movement between the interior of the furnace body 111 of the preheating unit 110 and the interior of the furnace body 121 of the heating unit 120 is interrupted (to some extent). It is possible to maintain the temperature.

In the present embodiment, the heating power (the amount of heat supplied to the inside of the furnace body 121) of the plurality of burners 123, 123. As a result, the temperature of the atmosphere inside the furnace body 121 is kept substantially constant from one end portion to the other end portion of the furnace body 121.
Therefore, the object carried into the furnace body 121 is kept at a predetermined temperature while being conveyed from one end portion of the furnace body 121 toward the other end portion by the conveying device 122.
Strictly speaking, the temperature of the atmosphere corresponding to the middle part of the furnace body 121 is the highest, and the temperature of the atmosphere corresponding to both ends of the furnace body 121 is slightly lower than that. The temperature of the object is also highest when it reaches the middle part of the furnace body 121.

The cooling unit 130 is a part of the heating furnace 100 that cools (decreases) an object from a predetermined temperature to near room temperature.
The cooling unit 130 includes a furnace body 131, a transfer device 132, a second partition door 134, and an exit door 135.

The furnace body 131 is a combination of a generally cylindrical (tunnel-shaped) structure that forms the cooling unit 130 and a refractory material that covers the inner peripheral surface of the structure. Openings are formed at both ends of the furnace body 131.
The opening formed at one end of the furnace body 131 is connected to the opening formed at the other end of the furnace body 121 of the heating unit 120. Therefore, the inside of the furnace body 131 of the cooling unit 130 communicates with the inside of the furnace body 121 of the heating unit 120.

The transfer device 132 is disposed inside the furnace body 131, and an object formed in the furnace body 131 is opened at the other end of the furnace body 131 from an opening formed at one end of the furnace body 131. It is an apparatus which conveys toward a part.
The transport device 132 of this embodiment is a roller conveyor, but may be replaced with another type of device as long as the object can be moved inside the furnace body 131.

The second partition door 134 is a door provided in an opening (a communication portion between the interior of the furnace body 121 and the interior of the furnace body 131) formed at one end of the furnace body 131.
By opening the second partition door 134, it is possible to move the object from the inside of the furnace body 121 of the heating unit 120 to the inside of the furnace body 131 of the cooling unit 130.
By closing the second partition door 134, gas movement between the interior of the furnace body 121 of the heating unit 120 and the interior of the furnace body 131 of the cooling unit 130 is blocked (to some extent) It is possible to maintain the temperature.

In the present embodiment, the cooling unit 130 does not include a device (such as a burner) for heating the atmosphere inside the furnace body 131.
Accordingly, the object carried into the furnace body 131 is gradually cooled (temperature is lowered) while being conveyed from one end of the furnace body 131 toward the other end by the conveying device 132.

The exit door 135 is a door provided at an opening formed at the other end of the furnace body 131.
By opening the outlet door 135, it is possible to carry the object from the inside of the furnace body 131 to the outside of the heating furnace 100 through the opening formed at the other end of the furnace body 131.
By closing the outlet door 135, the gas inside the furnace body 131 is prevented from escaping to the outside of the furnace body 131 through the opening formed at the other end of the furnace body 131, and the temperature inside the furnace body 131 is reduced. It is possible to hold.

The heating furnace 100 of the present embodiment supplies a gas having a composition different from that of the outside air (atmosphere) to the inside of the heating furnace 100 (a combination of the inside of the furnace body 111, the inside of the furnace body 121, and the inside of the furnace body 131). There is no equipment.
Therefore, the atmosphere inside the heating furnace 100 has substantially the same composition as the atmosphere, and is an oxidizing atmosphere (an atmosphere that can promote the oxidation of the heated object).

Below, the instrument 10 for zinc separation which is one Embodiment of the instrument for zinc separation which concerns on this invention using FIG. 2 and FIG. 3 is demonstrated.
The zinc separating device 10 is a device for separating (removing) zinc from the galvanized steel plate scraps 1, 1... Shown in FIG.

  The galvanized steel sheet scrap 1 is a remaining part (peripheral part or the like) after punching out a part having a predetermined shape from the galvanized steel sheet. A galvanized steel sheet is obtained by coating the surface of a steel sheet with a zinc layer (a zinc layer is formed on the surface of the steel sheet).

The galvanized steel plate scrap 1 is an embodiment of the zinc-attached iron material according to the present invention.
“Zinc-attached iron material” refers to a material in which zinc is attached to the surface of an iron material.
"Iron material" refers to an object containing iron or an iron alloy (an alloy whose main material is iron). The iron alloy includes steel (an alloy of iron and carbon).
The shape of the iron material is not limited to a plate shape, and may be another shape (for example, a lump shape, a shape obtained by rolling a plate-like iron material like paper waste, or the like).
In “the state where zinc is attached to the surface of the iron material”, in addition to the state where the surface of the iron material is coated with a zinc layer like a galvanized steel sheet, the state where the iron material and zinc are mixed (for example, on the surface of the iron material) Including zinc dust).
Specific examples of the zinc-adhered iron material include galvanized steel sheets, galvanized steel sheet scraps, cutting scraps generated when cutting galvanized steel sheets, and galvanized objects made of cast iron.

  As shown in FIGS. 2 and 3, the zinc separating device 10 includes a basket 11 and a ceramic filter 12.

The basket 11 is an embodiment of a container according to the present invention.
The basket 11 of the present embodiment is made of ceramics (more specifically, SiC).
The outer shape of the basket 11 is substantially a rectangular parallelepiped shape, and a space for accommodating the galvanized steel plate scraps 1, 1... And the calcine coke 2. Is done.
An opening 11 a is formed on the upper surface of the basket 11. The inside of the basket 11 (the space) communicates with the outside of the basket 11 through the opening 11a.

Calcine coke 2 · 2... Is an embodiment of the carburizing agent according to the present invention.
The calcine coke 2 of the present embodiment is a granular (or powdery) solid having a diameter of several tens of μm to several mm.
A “carburizing agent” refers to an object that can release (supply) carbon to the surrounding atmosphere when heated. Specific examples of the carburizing agent include various cokes, graphite, and carbon-containing soot (dust).
The coke includes petroleum coke in addition to carbonized coal.
Petroleum coke is coke produced by petroleum refining, and is a residue obtained by subjecting heavy oil (for example, atmospheric distillation residue, vacuum distillation residue, etc.) to a pyrolysis process called coking.
Petroleum coke includes delayed coke and fluid coke.
Delayed coke includes raw coke and calcined coke.
Raw coke is petroleum coke as it is collected from a coking device (device for coking).
Calcine coke is obtained by removing moisture and volatile components from raw coke by heating (calcining) the raw coke once again.

The ceramic filter 12 is an embodiment of a lid according to the present invention.
The ceramic filter 12 of the present embodiment is a plate-like member made of ceramics (more specifically, SiC), and has a pair of upper and lower plate surfaces. The shape of the pair of plate surfaces of the ceramic filter 12 is generally rectangular. The ceramic filter 12 is fixed (fitted) to the opening 11 a of the basket 11.
The ceramic filter 12 has a plurality of vent holes 12a, 12a,.
The plurality of vent holes 12a, 12a, ... penetrate through a pair of upper and lower plate surfaces of the ceramic filter 12. Therefore, when the ceramic filter 12 is fixed to the opening 11a of the basket 11, the plurality of vent holes 12a, 12a,.

Below, one Embodiment of the zinc separation method which concerns on this invention is described using FIGS. 1-5.
One embodiment of the zinc separation method according to the present invention is a method for separating (removing) zinc from the galvanized steel sheet scraps 1... Shown in FIG. .
As shown in FIG. 4, an embodiment of the zinc separation method according to the present invention includes an accommodation step S1100 and an evaporation step S1200.

In the housing step S1100, first, galvanized steel plate scraps 1 · 1... And calcine coke 2 · 2... Are accommodated in the basket 11 of the zinc separating instrument 10.
As shown in FIG. 3, in this embodiment, a part of the calcine coke 2 · 2 ··· contained in the basket 11 is galvanized steel plate waste 1 ······ accommodated in the basket 11. The gap is filled. Further, the remaining part of the calcine coke 2 ····· accommodated inside the basket 11 is arranged above the galvanized steel plate scraps 1 ··· Layer.
Therefore, the “layer of calcine coke 2... 2” is formed between the opening 11 a of the basket 11 and the galvanized steel plate scraps 1, 1. It becomes. Hereinafter, the “layer of calcine coke 2... 2” disposed above the galvanized steel plate scraps 1, 1... Is referred to as “barrier layer 3 by calcine coke 2”.

In the housing step S1100, the ceramic filter 12 is then fixed (fitted) to the opening 11a of the basket 11.
As shown in FIG. 3, when the ceramic filter 12 is fixed to the opening 11 a of the basket 11, the calcine between the galvanized steel plate scraps 1... A barrier layer 3 made of coke 2 is disposed.

  In the evaporation step S1200, the zinc separating tool 10 (more specifically, in the accommodating step S1100, the galvanized steel plate scraps 1, 1,... And the calcine coke 2, 2,. A barrier layer 3 made of sine coke 2 is formed between the opening 11 a of the basket 11 and the galvanized steel plate scraps 1, 1... Accommodated inside the basket 11, and the ceramic filter 12 is opened to the opening 11 a of the basket 11. Are housed (arranged) in the heating furnace 100.

  In this embodiment, before the evaporation step S1200 is started, the inlet door 114, the first partition door 124, the second partition door 134, and the outlet door 135 of the heating furnace 100 are closed in advance, and a plurality of burners 113, 113,. .. and igniting a plurality of burners 123, 123... Keep the temperature of the atmosphere corresponding to the middle part of the furnace body 121 within the furnace body 121 of the heating unit 120 at 1050 ° C., and preheat The temperature of the atmosphere inside the furnace body 111 of the section 110 is changed from one end of the furnace body 111 (the end where the entrance door 114 is provided) to the other end (the one where the first partition door 124 is provided). The temperature of the atmosphere at the other end is kept at about 850 ° C.

1050 ° C., which is the temperature of the atmosphere corresponding to the middle part of the furnace body 121 in the present embodiment, is an example of the processing temperature according to the present invention.
The “treatment temperature” is a temperature inside the furnace set to evaporate zinc attached to the surface of the zinc-attached iron material.

The treatment temperature needs to be equal to or higher than the “minimum evaporation temperature of zinc”.
The “minimum evaporation temperature of zinc” is not necessarily higher than the boiling point of zinc (in the case of normal pressure (1 atm), 907 ° C.). There may be. Similarly, water can evaporate even at a temperature lower than 100 ° C., which is the boiling point of water at normal pressure, and zinc can evaporate even at a temperature slightly lower than the boiling point of zinc.

The processing temperature may be less than “the melting point of the iron part of the zinc-adhered iron material (in the case of this embodiment, the melting point of the steel material constituting the galvanized steel sheet scraps 1, 1... After the zinc has evaporated)”. desirable.
This is because when the processing temperature is set to be equal to or higher than the melting point of the iron part of the zinc-adhered iron material, the iron part of the zinc-adhered iron material melts and mixes with the carburizing agent in the container in the process of evaporating zinc, This is because when the steel material is taken out of the steel, the iron material portion solidifies in a form involving a carburizing agent, making it difficult to reuse (recycle) the iron material portion.

  In the evaporation step S1200, first, the entrance door 114 is opened, and the zinc separation tool 10 is accommodated in the furnace body 111 of the preheating unit 110 from the outside of the heating furnace 100. After the zinc separator 10 is accommodated in the furnace body 111 of the preheating unit 110, the inlet door 114 is closed.

The zinc separating instrument 10 housed inside the furnace body 111 of the preheating unit 110 is transferred from one end of the furnace body 111 (the end where the inlet door 114 is provided) to the other end (first) by the transfer device 112. It is conveyed toward the end of the one partition door 124 provided.
As a result, the temperature of the zinc separating tool 10 gradually increases and reaches about 850 ° C. when reaching the other end of the furnace body 111 (see from time zero to time T1 in FIG. 5).

Subsequently, the first partition door 124 is opened, and the zinc separating tool 10 moves from the inside of the furnace body 111 of the preheating unit 110 to the inside of the furnace body 121 of the heating unit 120. After the zinc separation instrument 10 is accommodated in the furnace body 121 of the heating unit 120, the first partition door 124 is closed.
The zinc separating instrument 10 housed in the furnace body 121 is transferred from one end (the end on which the first partition door 124 is provided) of the furnace body 121 to the other end (second partition) by the transfer device 122. It is conveyed toward the end of the side where the door 134 is provided.
The temperature of the zinc separating instrument 10 gradually increases and then decreases in the process of being transported from one end of the furnace body 121 toward the other end by the transport device 122.
More specifically, the temperature of the zinc separating tool 10 rises to 1050 ° C. when it reaches the middle part of the furnace body 121 and falls to 900 ° C. when it reaches the other end (time T1 in FIG. 5). To time T2).

When the zinc separating tool 10 is arranged inside the furnace body 121 of the heating unit 120, the carbon constituting the calcine coke 2 housed in the basket 11 of the zinc separating tool 10 and the furnace body 121 Gaseous oxygen (O ₂ ) contained in the internal atmosphere reacts to generate carbon monoxide (CO) and carbon dioxide (CO ₂ ).
In addition, when volatile components such as hydrocarbons remain in the calcine coke 2, the hydrocarbons react (combust) with gaseous oxygen to generate carbon monoxide, carbon dioxide, and water (steam).
The generated carbon monoxide and carbon dioxide fill the inside of the basket 11, and the surplus portion of the generated carbon monoxide and carbon dioxide passes through the gap between the granular calcine cokes 2. 12 is discharged to the outside of the basket 11 (the space inside the furnace body 121) through the vent holes 12a, 12a,.
As described above, although the atmosphere in the furnace of the heating furnace 100 (inside the furnace body 121) is an oxidizing atmosphere as a whole, the inside of the basket 11 of the zinc separation instrument 10 is locally reduced (substance). In other words, an atmosphere that inhibits the substance from being oxidized).
Accordingly, the galvanized steel plate scraps 1, 1... Housed in the basket 11 are covered with a reducing atmosphere, and there is almost no gaseous oxygen around the galvanized steel plate scraps 1, 1. It becomes.

In this embodiment, a barrier layer 3 made of calcine coke 2... 2 is formed between the opening 11 a of the basket 11 and the galvanized steel plate scraps 1, 1. Therefore, in order for the gaseous oxygen contained in the atmosphere inside the furnace body 121 to reach the vicinity of the surface of the galvanized steel plate scraps 1. It is necessary to pass through a gap between calcine cokes 2.
However, when the zinc separating tool 10 is disposed inside the furnace body 121 of the heating unit 120, the temperature of the zinc separating tool 10 (and thus the temperature inside the basket 11) is maintained at 850 ° C. or higher. In the process of passing through the barrier layer 3, most of the gaseous oxygen contained in the atmosphere inside the furnace body 121 reacts with the carbon derived from calcine coke 2. It becomes carbon oxide or carbon dioxide.
Therefore, it is almost impossible for gaseous oxygen to reach the vicinity of the surface of the galvanized steel sheet scraps 1, 1... As they are (without becoming carbon monoxide or carbon dioxide).

Since the boiling point of zinc at normal pressure (1 atm) is 907 ° C., in this embodiment, the galvanized steel plate scraps 1.・ Zinc is actively evaporated from the surface.
In the present embodiment, when the zinc separation tool 10 is disposed inside the furnace body 121 of the heating unit 120, the gaseous oxygen is carbon derived from calcine coke 2... Constituting the barrier layer 3. Reacts with carbon monoxide or carbon dioxide, so that the portion of the inside of the basket 11 that is opposite to the opening 11a of the basket 11 with the barrier layer 3 made of calcine coke 2 in particular, that is, the galvanized steel sheet There is almost no gaseous oxygen in the part where the scraps 1.
Therefore, the evaporated zinc passes through the gap between the granular calcine coke 2... Together with the excess carbon monoxide and carbon dioxide while maintaining the metallic state, and further, the air holes 12 a. 12a ... is discharged to the outside of the basket 11 (the space inside the furnace body 121).
In this way, zinc is separated from the galvanized steel plate scraps 1... (The galvanized steel plate scraps 1... Are separated into iron and zinc).
The metallic zinc released to the outside of the basket 11 (the space inside the furnace body 121) reacts with gaseous oxygen in the atmosphere inside the furnace body 121 to form zinc oxide (ZnO). To do. Since the melting point of zinc oxide is 1975 ° C., zinc oxide condenses inside the furnace body 121.

In the present embodiment, when the zinc separation tool 10 is disposed inside the furnace body 121 of the heating unit 120, the gaseous oxygen is carbon derived from calcine coke 2... Constituting the barrier layer 3. Reacts with carbon monoxide or carbon dioxide, so that the portion of the inside of the basket 11 that is opposite to the opening 11a of the basket 11 with the barrier layer 3 made of calcine coke 2 in particular, that is, the galvanized steel sheet There is almost no gaseous oxygen in the part where the scraps 1.
Therefore, the surface of the galvanized steel sheet scraps 1, 1... After the zinc has evaporated and the gaseous oxygen hardly contact each other.
Therefore, it is possible to prevent the galvanized steel sheet scraps 1, 1... After the zinc has evaporated from being oxidized and the generation of scales made of iron oxide on the surface of the galvanized steel sheet scraps 1.
As a result, the recovery amount of the obtained iron material (in this embodiment, galvanized steel plate scraps 1, 1... After the zinc has evaporated) increases (a decrease in the recovery yield of the iron material is suppressed).

Subsequently, the second partition door 134 is opened, and the zinc separating tool 10 moves from the inside of the furnace body 121 of the heating unit 120 to the inside of the furnace body 131 of the cooling unit 130. After the zinc separating instrument 10 is accommodated in the furnace body 131 of the cooling unit 130, the second partition door 134 is closed.
In addition, by the time the zinc separation instrument 10 moves from the inside of the furnace body 121 of the heating unit 120 to the inside of the furnace body 131 of the cooling unit 130, the evaporation of zinc from the galvanized steel plate scraps 1, 1. (Almost) finished.

  Since the atmosphere inside the furnace body 131 is not particularly heated by a burner or the like, the temperature of the zinc separating instrument 10 housed inside the furnace body 131 is adjusted by the transfer device 132 to one end of the furnace body 131 (second partition door). 5 is gradually lowered to near room temperature in the process of being conveyed from the end provided with 134 to the other end (end provided with the exit door 135) (time in FIG. 5). See T2 and later).

Subsequently, the outlet door 135 is opened, and the zinc separating tool 10 is carried out from the inside of the furnace body 131 of the cooling unit 130 to the outside of the heating furnace 100. After the zinc separating tool 10 is carried out of the heating furnace 100, the outlet door 135 is closed.
The ceramic filter 12 of the instrument for separating zinc 10 carried out of the heating furnace 100 is removed from the basket 11, and iron material (in this embodiment, galvanized steel plate scraps 1 and 1 after zinc is evaporated) is removed from the basket 11. ...) And calcine coke 2.
The extracted iron material is reused as a raw material for cast iron. The extracted calcine coke 2 · 2... Is accommodated again in the basket 11 together with the galvanized steel plate scrap 1 ·····, and the barrier layer 3 is formed by the calcine coke 2 (and the galvanized steel plate scrap 1・ Reuse for 1 ...
It is possible to prevent oxidation of the galvanized steel plate scraps 1, 1... After the zinc has evaporated by gradually cooling the zinc separating tool 10 in the cooling unit 130 and then carrying it out of the heating furnace 100. Is possible. Moreover, it is possible to prevent damage or deformation | transformation of the zinc separation instrument 10 by the temperature of the instrument 10 for zinc separation changing rapidly.

Hereinafter, the “change in the concentration of zinc contained in the iron material” when one embodiment of the zinc separation method according to the present invention is performed will be described with reference to FIG.
In conducting the experiment for confirming the “change in the concentration of zinc contained in the iron material”, the following three experimental conditions (α), (β), and (γ) were set.
(Α) The zinc-plated steel plate scraps 1 are not particularly subjected to a treatment for separating zinc, and are directly melted in a high-frequency induction furnace for producing a raw material for cast iron (see white circles in FIG. 6).
(Β) A conventional raw material for cast iron is manufactured after performing “conventional separation of zinc (treatment of evaporating zinc by heating in a vacuumed heating furnace)” on the galvanized steel sheet scraps 1. For melting (see black circles in FIG. 6).
(Γ) In a high-frequency induction furnace for producing a raw material for cast iron after performing “treatment for separating zinc corresponding to one embodiment of the zinc separation method according to the present invention” on the galvanized steel plate scrap 1 Dissolve (see white squares in FIG. 6).
Three galvanized steel plate scraps 1 · 1 · 1 that are known in advance to have the same zinc concentration (% by weight) were prepared and used for the above (α), (β), and (γ), respectively.

  As shown in FIG. 6, (1) Before the zinc separation, the zinc concentrations of the three galvanized steel plate scraps 1 · 1 · 1 provided for (α), (β) and (γ) are all set to 1. It was 00% by weight.

As shown in FIG. 6, (2) At the time after zinc separation, the zinc concentrations of the two galvanized steel sheet scraps 1 and 1 provided for (β) and (γ) are both (1) the time before zinc separation. Than that.
Moreover, at the time after (2) zinc separation, the zinc concentration (0.02% by weight) of the galvanized steel plate scrap 1 provided for (γ) is the zinc concentration of the galvanized steel plate scrap 1 provided for (β). (0.04% by weight).
As shown in FIG. 6, (3) At the time after melting, the zinc concentrations of the two galvanized steel plate scraps 1 and 1 provided for (β) and (γ) are both (2) at the time after zinc separation. Declined from the time. This is because a part of zinc adhering to the galvanized steel plate scraps 1 evaporates even when melting in the high frequency induction furnace.
Moreover, at the time after (3) melting, the zinc concentration (0.01 wt%) of the galvanized steel plate scrap 1 subjected to (γ) is the zinc concentration of the galvanized steel plate scrap 1 subjected to (β) ( 0.035% by weight).

  Thus, it was confirmed that one embodiment of the zinc separation method according to the present invention can separate (remove) zinc as much as or more than the conventional zinc separation method.

As described above, one embodiment of the zinc separation method according to the present invention is as follows.
In the basket 11 in which the opening 11a is formed, the galvanized steel plate scraps 1 · 1 and the calcine coke 2 ··· 2 are accommodated and the galvanized steel plate scraps 1 · 1 and the opening part 11a, the accommodating process S1100 which forms the barrier layer 3 by the calcine coke 2;
The basket 11 containing the galvanized steel plate scraps 1 ···· and the calcine coke 2 ····· 2 is disposed inside the heating furnace 100 and the temperature inside the furnace is set to the processing temperature (in this embodiment). Evaporating step S1200 for evaporating zinc from the galvanized steel sheet scraps 1.
It comprises.
By configuring in this way, even when the galvanized steel plate scraps 1, 1... Are heated using the heating furnace 100 in which the internal atmosphere is an oxidizing atmosphere, the galvanized steel plate scraps 1. It is possible to separate the zinc from the galvanized steel plate scraps 1, 1... Without oxidizing the part.
Further, other furnaces in the heating furnace 100, a furnace having a structure in which the atmosphere in the furnace cannot be filled with a reducing atmosphere, or a structure in which oxygen intrudes into the furnace such as a furnace using a burner cannot be avoided. Since it is possible to separate zinc from the galvanized steel plate scraps 1, 1... Without oxidizing the surface of the galvanized steel plate scraps 1, 1,. (Specifically, changing the heating method, adding a device for introducing a reducing atmosphere into the furnace, etc.) is not necessary, and the cost required for remodeling the furnace can be suppressed.

An embodiment of the zinc separation method according to the present invention is as follows:
In the housing step S1100,
.. Are filled in the gaps between the galvanized steel plate scraps 1, 1... Housed in the basket 11.
With this configuration, even when the storing step S1100 is performed in an oxidizing atmosphere such as the air, the galvanized steel sheet scraps 1, 1. In the gap between the galvanized steel plate scraps 1, 1,... Can be minimized.
Therefore, it is possible to further reduce the amount of oxidation of the galvanized steel plate scraps 1, 1... After the zinc has evaporated, and consequently the recovery of the galvanized steel plate scraps 1. It is possible to increase the amount (to prevent a reduction in the recovery yield).

An embodiment of the zinc separation method according to the present invention is as follows:
In the housing step S1100,
By fixing the ceramic filter 12 in which the air holes 12a communicating the inside and outside of the basket 11 are formed to the opening 11a of the basket 11, the galvanized steel plate scraps 1. A barrier layer 3 made of calcine coke 2 is disposed between the ceramic filter 12 and
With this configuration, contact between the barrier layer 3 by the calcine coke 2 and the oxidizing atmosphere inside the heating furnace 100 is suppressed as much as possible, and the wear of the barrier layer 3 by the calcine coke 2 (reducing atmosphere inside the basket 11). It is possible to suppress the oxidation (combustion) of calcine coke 2 in a form that does not contribute to filling with (carbon monoxide and carbon dioxide).
In addition, when the inside of the furnace body 121 is heated by a plurality of burners 123, 123..., The portion directly exposed to the fire of the burners 123, 123. There is a case. When the fire of the burners 123, 123... Is directly applied to the surface of the barrier layer 3 by the calcine coke 2 (in this embodiment, the upper surface of the barrier layer 3), the calcine coke 2 constituting the barrier layer 3 is used. -Adjacent ones of 2 ... may stick together, and the gap between the adjacent ones may be blocked to prevent the evaporated zinc from being released to the outside. By fixing the ceramic filter 12 to the opening 11 a of the basket 11, it is possible to prevent the fire of the burners 123, 123... From directly hitting the surface of the barrier layer 3 by the calcine coke 2.

As described above, the zinc separating tool 10 is:
An opening portion 11a is formed, galvanized steel plate scraps 1 ···· and calcine coke 2 ···· 2 are accommodated therein, and galvanized steel plate scraps 1 ···· 1 accommodated therein. And a basket 11 in which a barrier layer 3 made of calcine coke 2 is formed.
By configuring in this way, even when the galvanized steel plate scraps 1, 1... Are heated using the heating furnace 100 in which the internal atmosphere is an oxidizing atmosphere, the galvanized steel plate scraps 1. It is possible to separate the zinc from the galvanized steel plate scraps 1, 1... Without oxidizing the part.
Further, other furnaces in the heating furnace 100, a furnace having a structure in which the atmosphere in the furnace cannot be filled with a reducing atmosphere, or a structure in which oxygen intrudes into the furnace such as a furnace using a burner cannot be avoided. Since it is possible to separate zinc from the galvanized steel plate scraps 1, 1... Without oxidizing the surface of the galvanized steel plate scraps 1, 1,. (Specifically, changing the heating method, adding a device for introducing a reducing atmosphere into the furnace, etc.) is not necessary, and the cost required for remodeling the furnace can be suppressed.

Moreover, the instrument 10 for separating zinc is
The ceramic filter 12 is provided with vent holes 12a, 12a,... That communicate between the inside and the outside of the basket 11 when fixed to the opening 11a of the basket 11.
With this configuration, when the ceramic filter 12 is fixed to the opening 11 a of the basket 11, the galvanized steel sheet scraps 1... The barrier layer 3 made of calcine coke 2 is disposed.
As a result, contact between the barrier layer 3 by the calcine coke 2 and the oxidizing atmosphere inside the heating furnace 100 is suppressed as much as possible, and the wear of the barrier layer 3 by the calcine coke 2 (reduction atmosphere (carbon monoxide and It is possible to suppress oxidation (combustion) of calcine coke 2 in a form that does not contribute to filling with carbon dioxide).
In addition, when the inside of the furnace body 121 is heated by a plurality of burners 123, 123..., The portion directly exposed to the fire of the burners 123, 123. There is a case. When the fire of the burners 123, 123... Is directly applied to the surface of the barrier layer 3 by the calcine coke 2 (in this embodiment, the upper surface of the barrier layer 3), the calcine coke 2 constituting the barrier layer 3 is used. -Adjacent ones of 2 ... may stick together, and the gap between the adjacent ones may be blocked to prevent the evaporated zinc from being released to the outside. By fixing the ceramic filter 12 to the opening 11 a of the basket 11, it is possible to prevent the fire of the burners 123, 123... From directly hitting the surface of the barrier layer 3 by the calcine coke 2.

The heating furnace 100 of this embodiment is a burner type furnace (usually a furnace that heats an object by igniting the gas while injecting a gas containing hydrocarbon gas and oxygen from a burner nozzle). The method in which the furnace according to the invention heats the instrument for separating zinc according to the present invention (method for generating the heat required for heating) is not limited to this.
That is, the furnace according to the present invention may be a furnace that heats the zinc separation device according to the present invention by another method (for example, a method of heating with an electric heater).

The heating furnace 100 according to the present embodiment is a so-called tunnel furnace, and includes a transfer device (the transfer device 112, the transfer device 122, and the transfer device 132) in the interior thereof, and appropriately sets the temperature distribution in the furnace, thereby attaching zinc. Zinc separation device containing iron material and carburizing agent (in this embodiment, zinc separation device 10 containing galvanized steel plate scraps 1 · 1 ... and calcine coke 2 ··· 2). Although it heats, conveying it with a conveying apparatus, it cools after that, The furnace which concerns on this invention does not necessarily require a conveying apparatus.
That is, the furnace according to the present invention does not include a transfer device inside the furnace, and appropriately adjusts the amount of heat generated by a device for heating (burner, electric heater, etc.) so that the inside of the furnace (atmosphere) A furnace whose temperature can be adjusted may be used.

Although the atmospheric pressure inside the heating furnace 100 of this embodiment is a normal pressure (1 atm), the atmospheric pressure inside the furnace according to the present invention is not limited to this.
That is, the furnace according to the present invention may be a furnace capable of pressurizing or depressurizing the internal pressure of the furnace with respect to normal pressure.

Although the external shape of the basket 11 of this embodiment is a substantially rectangular parallelepiped shape, the shape of the container of the zinc separation instrument according to the present invention is not limited to this.
Other examples of the outer shape of the container for the zinc separation device according to the present invention include a cubic shape and a cylindrical shape.

Although the opening part 11a is formed in the upper surface of the basket 11 of this embodiment, the position of the opening part formed in the container of the instrument for zinc separation which concerns on this invention is not limited to this.
That is, you may form an opening part not only in the upper surface of the container of a zinc separation instrument but in a side surface or a lower surface.
However, the zinc-attached iron material and the carburizing agent contained in the container for zinc separation are not spilled to the outside from the opening, and zinc separated (evaporated) from the zinc-attached iron material is removed from the opening to the container. It must be possible to release to the outside.

The number of openings formed in the container of the zinc separation instrument according to the present invention may be single or plural.
That is, it is formed in the container for the zinc separation device according to the present invention from the viewpoint of easy release of the zinc separated (evaporated) from the zinc-adhered iron material to the outside, prevention of wear of the carburizing agent, and the like. It is desirable to select the number of openings as appropriate.

The opening 11a formed in the basket 11 of the present embodiment has a function as a carry-in path when accommodating the galvanized steel plate scraps 1, 1... And the calcine coke 2. , Which also functions as a movement path for releasing (evaporated) zinc separated from the galvanized steel sheet scraps 1, 1... To the outside of the basket 11, but the present invention is not limited to this.
That is, the zinc separation tool according to the present invention was separated from the zinc adhesion iron material into the opening as a carry-in path when accommodating the zinc adhesion iron material and the carburizing agent inside the container (vaporized). ) Openings as movement paths for releasing zinc to the outside of the container may be formed separately.

Although the material which comprises the basket 11 of this embodiment and the ceramic filter 12 is all SiC, the material which comprises the container and lid | cover of the instrument for zinc separation which concerns on this invention is not limited to this.
That is, the materials constituting the container and lid of the zinc separation instrument according to the present invention are unnecessary between the zinc-adhered iron material and the carburizing agent even when heated inside the furnace (recovery of iron material or carburizing agent). It is desirable that the material satisfy the two requirements that it does not cause a chemical reaction (such as a decrease in yield and quality of the iron material) and does not melt or deform even when heated to the processing temperature. .
Specific examples of the material constituting the container and the lid of the zinc separation instrument according to the present invention include various steel materials, various ceramics, and the like.

Although the zinc separation device 10 of the present embodiment includes the basket 11 and the ceramic filter 12, the zinc separation device of the present invention is not limited thereto. That is, the instrument for separating zinc according to the present invention may be configured without a lid.
When the instrument for separating zinc according to the present invention does not have a lid, it is easier to release zinc to the outside of the container than when it has a lid. It is possible to keep the weight (concentration) of zinc contained low, (b) it is possible to shorten the time (heating time) required to evaporate (separate) zinc, (c) treatment There are various advantages such that the temperature can be kept low.
On the other hand, when the instrument for separating zinc according to the present invention does not have a lid, the carburizing agent is more likely to come into contact with the oxidizing atmosphere in the furnace as compared with the case where the lid is provided. There is a problem in that the oxidation (combustion) of the carburizing agent in a form that does not contribute to satisfying in a reducing atmosphere increases.
Therefore, it is desirable to appropriately select whether or not the zinc separating instrument according to the present invention is provided with a lid in consideration of the above advantages and problems.

  In the ceramic filter 12 of this embodiment, vent holes 12a, 12a, ... are formed. The number, shape, diameter, distribution (arrangement), etc. of the communication holes formed in the lid according to the present invention are determined according to the container. It is desirable to select appropriately considering the ease of zinc release to the outside and the wear of the carburizing agent.

The diameter of the calcine coke 2 of the present embodiment is about several tens of μm to several mm, but the size (particle size) of the carburizing agent according to the present invention is not limited to this.
The size of the carburizing agent is a factor that affects the size of the gas transfer path in the “barrier layer by the carburizing agent” (that is, the gap between the carburizing agents) and the total surface area of the carburizing agent.
The smaller the size (particle size) of the carburizing agent, the narrower the gas transfer path in the “barrier layer by carburizing agent”. Therefore, the gas flow between the inside and outside of the container sandwiching the barrier layer by the carburizing agent is reduced. It becomes difficult to move. This is preferable in that the oxidizing atmosphere hardly reaches the surface of the zinc-adhered iron material through the barrier layer, but is not preferable in that evaporated zinc is difficult to be released to the outside of the container.
Moreover, since the sum total of the surface area of a carburizing agent becomes large, so that the size (particle diameter) of a carburizing agent becomes small, the contact area of a carburizing agent and oxidizing atmosphere becomes large. This suppresses the oxidation of the iron material after the zinc is separated by promoting the chemical reaction between the carburizing agent and oxygen and always filling the interior of the container with a reducing atmosphere (carbon monoxide and carbon dioxide). However, it is not preferable in that the wear of the carburizing agent is increased.
Accordingly, the size (particle size) of the carburizing agent according to the present invention is appropriately selected in consideration of the size of the gas transfer path in the “barrier layer by the carburizing agent” and the total surface area of the carburizing agent. It is desirable.

In this embodiment, the volume ratio of the galvanized steel plate scraps 1 · 1... And calcine coke 2 · 2... Accommodated in the basket 11 is approximately 3: 1, but the present invention is not limited to this. .
The volume ratio of the zinc-adhered iron material and the carburizing agent accommodated in the container according to the present invention is the amount of zinc adhering to the zinc-adhered iron material, the processing temperature, the shape of the container (the shape of the internal space of the container, the opening It is desirable to select appropriately considering the size and the like.

  In addition, since the calcine coke 2 used as a carburizing agent in this embodiment has less volatile content than other types of coke, it is excellent in that the wear when heated is small.

1 Galvanized steel sheet scrap (zinc-attached iron material)
2 Calcine coke (carburizing agent)
3 Barrier Layer 10 Zinc Separation Equipment 11 Basket (Container)
11a Opening 12 Ceramic filter (lid)
12a Vent 100 Heating furnace (furnace)
110 Preheating part 113 Burner 120 Heating part 123 Burner 130 Cooling part

Claims (6)

A zinc-adhered iron material and a carburizing agent are accommodated in a container in which an opening is formed, and a barrier layer made of the carburizing agent is formed between the zinc-adhered iron material and the opening accommodated in the container. A containment process,
The container containing the zinc-adhered iron material and the carburizing agent is disposed inside an oven in an oxidizing atmosphere, and the temperature inside the furnace is equal to or higher than the lower limit evaporation temperature of zinc adhering to the surface of the zinc-adhered iron material and An evaporation step of evaporating zinc from the zinc-adhered iron material by raising it to a treatment temperature that is a temperature that is less than the melting point of the iron part of the zinc-adhered iron material;
A method for separating zinc. In the housing step,
The zinc separation method according to claim 1, wherein a gap between the zinc-adhered iron materials accommodated in the container is filled with the carburizing agent. In the housing step,
A lid formed with a vent hole communicating the inside and the outside of the container is fixed to the opening of the container, so that the additional iron is placed between the zinc-adhered iron material housed in the container and the lid. The zinc separation method according to claim 1 or 2, wherein a barrier layer made of a charcoal agent is disposed.   An opening is formed, a zinc-adhered iron material and a carburizing agent are accommodated therein, and a barrier layer made of the carburizing agent is formed between the zinc-adhered iron material accommodated in the interior and the opening. An instrument for separating zinc comprising a container.   The instrument for separating zinc according to claim 4, further comprising a lid formed with a vent hole that communicates the inside and the outside of the container when fixed to the opening of the container.   The barrier layer made of the carburizing agent is disposed between the zinc-adhered iron material housed in the container and the lid when the lid is fixed to the opening of the container. Zinc separator.

Images