JP3120369B2 - Metal recovery method and recovery device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of recovering a metal for obtaining a metal product from a molten product containing a molten metal and slag, and a metal recovery apparatus for performing the method.

[0002]

2. Description of the Related Art Generally, in a molten product obtained by iron making or refining, in addition to a molten metal such as iron which can be used as it is in a subsequent process, a slag which cannot be used as it is in a molten or semi-molten state. Included in. For this reason, a metal collecting means for separating the molten metal from the slag from the molten product and recovering the metal product is required.

[0003] As a means for recovering metal, for example, the most basic method is to prepare a mold, inject a molten product into the mold, and perform specific gravity separation in the mold to recover the metal (first conventional method). Example). There is also a method of preparing a water tank and injecting a molten product into the stored water (second conventional example). Note that the second conventional example can be said to be a modification of the underwater dripping method originally used for producing ferromanganese and nickel.

[0004]

However, in the first conventional example, as in a general casting method, it takes time and effort to apply a mold release agent to the inner surface of the mold in advance. Further, since the mold is provided near the high-temperature melting furnace and the high-temperature molten product is injected, the mold is significantly damaged and deteriorated, and there is a problem in durability.
Further, in many cases, the molten product is scattered at the time of injection and cannot be injected well into the mold, so that the specific gravity separation is often insufficient.

Further, the second conventional example has almost no problem of scattering of the above-mentioned molten product, but is not practical in terms of the action of separating molten metal and slag. That is, the metal cooled by the storage water and formed into particles is sequentially deposited in the water tank while being mixed with the slag. For this reason, it is necessary to carry out the metal and slag deposited in the water tank using an unloader, and to separate them by magnetic separation or sieving. However, it is not reasonable to extract much more metal contained in the molten product by magnetic attraction than non-metal slag. On the other hand, when the metal is non-magnetic, the size difference between the metal particles and the slag is small and the separation is difficult when sieving.

An object of the present invention is to provide a metal recovery method and a metal recovery apparatus capable of recovering from a molten product a metal product sufficiently separated from slag so that it can be put into a subsequent step.

[0007]

According to the present invention, there is provided a water tank in which stored water is stored at a predetermined water level, and a mold is prepared in the stored water, and a molten product containing molten metal and slag is prepared. The molten metal is poured into the mold in the storage water, in which the molten metal and the slag are separated from the slag by a specific gravity before solidifying, and the molten metal is a massive metal having a predetermined size and shape. A method for recovering a metal, characterized by having a separation casting step of casting into a product, is obtained.

According to the present invention, there is further provided a method for recovering the metal, wherein a plurality of the molds are prepared, and a feeding device for sequentially transporting the plurality of molds in the storage water is provided, and the separation casting step is continuously performed. Is obtained.

According to the present invention, there is further provided a method for recovering the metal, wherein the temperature of the storage water is set to 80 ° C. or higher.

According to the present invention, there is also provided a method for recovering the metal, wherein the depth of the open end of the mold with respect to the surface of the stored water is set in accordance with the drop between the open end of the mold and the discharge position of the molten product. Is obtained.

According to the present invention, the head between the open end of the mold and the discharge position of the molten product is 800 to 1800.
mm, and the depth of the open end of the casting mold with respect to the surface of the stored water is set to 50 to 200 mm.

According to the present invention, there is also provided a rotary kiln for melting an object to be processed and discharging a molten product, and injecting the molten product from the discharge end of the rotary kiln into the mold in the storage water. A metal recovery method is obtained.

According to the present invention, the rotary kiln uses waste generated in the iron making and steel making processes of an ironworks as an object to be treated, and heats the object in a reducing atmosphere on the upstream side thereof. Thus, the method for recovering the metal can be obtained in which the oxide in the object to be processed is reduced and the object to be processed is melted to perform a reduction melting step of obtaining a molten product.

According to the present invention, a secondary combustion chamber for burning exhaust gas discharged together with the molten product from the discharge end is provided at the discharge end of the rotary kiln, and the water tank and the mold are connected to each other. A method for recovering the metal provided in the secondary combustion chamber in a state of being substantially isolated from the outside air is obtained.

According to the present invention, there is also provided a water tank for storing stored water at a predetermined water level, and a mold prepared in the stored water, wherein the molten metal and slag are contained in the mold in the stored water. The molten product containing the molten metal is injected into the mold, and the molten metal and the slag are separated from the slag in a specific gravity before being solidified. Thus, a metal recovery apparatus characterized by being cast into a metal is obtained.

According to the present invention, the casting machine further comprises a plurality of the molds, and a feeding device for sequentially transporting the plurality of molds in the storage water, and wherein the metal casting machine continuously performs the separate casting process. Is obtained.

According to the present invention, there is also obtained the metal recovery apparatus in which the temperature of the stored water is 80 ° C. or higher.

[0018] According to the present invention, further, the metal recovery apparatus may be configured such that a depth of the open end with respect to the surface of the stored water is set according to a drop between an open end of the mold and a discharge position of the molten product. Is obtained.

[0019] According to the present invention, the mold may have a drop of 800 to 18 between the open end and the discharge position of the molten product.
It is possible to obtain the metal recovery device that is set to 00 mm and the depth of the open end with respect to the surface of the stored water is set to 50 to 200 mm.

According to the present invention, there is further provided a rotary kiln for melting the object to be treated and releasing a molten product, wherein the molten product is introduced into the mold in the storage water from the discharge end of the rotary kiln. A recovery device for the injected metal is obtained.

Further, according to the present invention, the rotary kiln uses waste generated in the iron making and steel making processes of an ironworks as an object to be treated, and heats the object in a reducing atmosphere on the upstream side thereof. As a result, the metal recovery device that obtains a molten product by reducing the oxide in the object to be processed and melting the object to be processed is obtained.

According to the present invention, a secondary combustion chamber for combusting exhaust gas discharged from the discharge end together with the molten product is provided at the discharge end of the rotary kiln.
The metal recovery device is provided in which the water tank and the mold are provided in the secondary combustion chamber in a state where the water tank and the mold are substantially shielded from outside air.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method and an apparatus for recovering a metal according to the present invention will be described together.

[Embodiment 1] FIGS. 1A and 1B
BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are diagrams for explaining a metal recovery method and a metal recovery apparatus according to Embodiment 1 of the present invention, wherein FIG. 1A shows Embodiment 1 and FIG.

Since the temperature near the discharge end of the molten product of the melting furnace is very high, it is practically impossible to arrange the mold near the discharge end. On the other hand, as in the comparative example shown in FIG. 1B, a gutter portion 11 is provided at the discharge end of a melting furnace (not shown), and a predetermined distance (for example, 1000) is provided below the discharge end.
If the mold 30 is placed at a distance of at least 1 mm, the molten product will be scattered and cannot be injected into the mold 30 properly. Of course, specific gravity separation of molten metal and slag is impossible.

On the other hand, in the present invention shown in FIG. 1A, a predetermined distance (for example, 1000 mm)
In the above, the water tank 20 in which the stored water 21 is stored at a predetermined water level is prepared, and the mold 30 is prepared in the stored water 21. From the discharge end of the gutter 11 to the mold 30 in the stored water 21
Until the space 51 is covered by a cover 50 made of a metal plate or the like, and is substantially shielded from the atmosphere. Then, the molten product is injected into the mold 30 in the storage water 21 from the discharge end of the gutter portion 11, and the molten metal and the slag are separated in the mold 30 before the molten metal and the slag solidify. At the same time, a separate casting step of casting and collecting the molten metal into a massive metal product (valuable metal) having a predetermined size and shape is performed. In the mold 30, the slag solidifies on the metal product.

According to such a configuration, the molten product is injected into the mold 30 without being scattered by the buffering action of the stored water 21, and the specific gravity of the molten metal and the slag is sufficiently separated. Further, a massive metal product having a predetermined size and shape is obtained. Lumped metal products (mainly iron alloys) having a predetermined size and shape are, for example, low zinc substances that can be directly reused in the iron making process. Moreover, it is a more suitable form than a small granular material, even if it is used as a raw material for a steelmaking process or the like or is subjected to sieving.

[Second Embodiment] FIG. 2 is a diagram for explaining a metal recovery method and a metal recovery apparatus according to a second embodiment of the present invention.

Referring to FIG. 2, in the method for recovering metal according to the second embodiment, similarly to the first embodiment, discharge of gutter (not shown for convenience) of melting furnace 10 is performed. At a predetermined distance (for example, 1000 mm or more) below the end, a water tank 20 storing the stored water 21 at a predetermined water level is prepared, and a mold 30 is prepared in the stored water 21. The space from the discharge end of the gutter of the melting furnace 10 to the mold 30 in the storage water 21 is covered by a cover 50 made of a metal plate or the like, and is located in a space 51 substantially isolated from the atmosphere. Then, the molten product is injected into the mold 30 in the storage water 21 from the discharge end of the gutter portion, and in the mold 30, the molten metal is separated from the slag and the specific gravity before both the molten metal and the slag are solidified. ,
A separation casting process is performed in which the molten metal is cast into a massive metal product having a predetermined size and shape and collected.

In the second embodiment, the mold 3
0 and a plurality of molds 30
1 is provided with a feeding device 40 for sequentially transporting the inside of the apparatus. Then, the conveying speed of the mold 30 is set so that the separate casting process is performed in each mold 30, and the separate casting process is continuously performed. When the mold 30 is transported out of the water tank 20, a massive metal product having a predetermined size and shape is removed from the mold 30. At this time, since the massive metal product and the slag having a predetermined size and shape are solidified so as to form separate layers, they can be easily separated by applying an impact to both.

[Third Embodiment] In the second embodiment shown in FIG. 2, a drop between the open end of the mold 30 and the discharge position of the molten product (the discharge end of the melting furnace 10 (the discharge end of the gutter)). H _K , the depth H between the open end of the mold 30 and the surface of the stored water 21
_With respect to _W and the temperature of the storage water 21, the separation casting process is performed while changing each parameter, and the scattering state of a molten product in each separation casting process, the casting result of a metal product (separation state from slag, shape, etc.) An experiment for observing was performed.

The result of the experiment, as a cast result Preferred parameters massive metallic product having a scattering state and a predetermined size and shape of the molten product, the difference H _K from 800 to 1
It was 800 mm. The depth H _W should be set according to the head H _K and was 50-200 mm. When the head H _K is 800 to 1800 mm, the depth H _{W is set} to 50.
By setting the thickness to 200 mm, scattering of the molten product from the mold could be almost completely suppressed. Further, the temperature of the storage water 21 is preferably 80 ° C. or higher. By setting the temperature of the storage water 21 to 80 ° C. or higher, the molten metal can be separated from the slag and the specific gravity before the molten metal solidifies.

These values are also considered to be preferable values in the first embodiment shown in FIG.

[Fourth Embodiment] In the first to third embodiments shown in FIG. 1 (a) or FIG. 2, the melting furnace for discharging the molten product to the mold 30 in the storage water 21 is to be treated. A rotary kiln that melts the material and releases the molten product can be used. As a rotary kiln, as proposed in Japanese Patent Application No. 8-330505, a waste generated at a steelworks is treated as a material to be treated, and the material to be treated is moved from an upstream side to a downstream side. It may be used in a method for recycling waste generated from steelworks for recovering valuable metals from inside. Even when the molten product is injected from the rotary kiln into the mold 30 in the storage water 21, the molten metal is separated from the slag and the specific gravity in the mold 30 before both the molten metal and the slag are solidified, and the molten metal is separated. It can be recovered by casting into a lump-shaped metal product having a predetermined size and shape.

[Embodiment 5] In addition to completely burning unburned substances in the exhaust gas discharged together with the molten product from the discharge end of the rotary kiln, high-temperature thermal decomposition of harmful substances such as dioxin is also performed. A secondary combustion chamber for discharging harmless gas out of the system was provided in connection with the discharge end of the rotary kiln. Further, a configuration is provided in the secondary combustion chamber, in which the cover 50 is removed from the recovery device of the first to fourth embodiments shown in FIG. 1A or FIG. Therefore, the chamber wall of the secondary combustion chamber replaces the cover 50, and the casting machine is substantially isolated from the outside air.

Incidentally, the calorie of the high-temperature rotary kiln exhaust gas and the heat of combustion in the secondary combustion chamber may be recovered as steam by providing a boiler at the subsequent stage to reduce the heat loss of the entire process.

[0037]

According to the metal recovery method of the present invention, a water tank storing stored water at a predetermined water level is prepared, a mold is prepared in the stored water, and a molten product containing molten metal and slag is stored in the stored water. Injection into a mold, separation of the molten metal and slag before solidification of both the molten metal and slag in the mold, and separation of the molten metal into a massive metal product having a predetermined size and shape Since it has a casting process, a metal product sufficiently separated from the slag so that it can be put into a subsequent process can be recovered from the molten product.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a metal recovery apparatus and a metal recovery method according to a first embodiment of the present invention;
Shows a first embodiment, and (b) shows a comparative example.

FIG. 2 is a diagram for explaining a metal recovery apparatus and a metal recovery method according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Melting furnace 11 Gutter part 20 Water tank 21 Storage water 30 Mold 40 Feeder 50 Cover 51 Space

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshio Matsuoka 5-2, Sokai-cho, Niihama-shi, Ehime Prefecture Sumitomo Heavy Industries Machinery Co., Ltd. Niihama Works (72) Inventor Shin-ichi Kuromazu 5-2, Sokai-cho, Niihama-shi, Ehime Sumitomo Heavy Industries Machinery Co., Ltd. Niihama Works (72) Inventor Hiroshi Koide 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal Industries, Ltd.Wakayama Works (72) Inventor Shigeru Morishita 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal Industries Co., Ltd. Company Wakayama Works (58) Field surveyed (Int. Cl. ⁷ , DB name) B22C 9/08

Claims (16)

(57) [Claims] A water tank storing stored water at a predetermined water level is prepared, a mold is prepared in the stored water, and a molten product containing molten metal and slag is injected into the mold in the stored water, In the mold, a separation casting step of separating the molten metal from the slag by specific gravity before solidifying both the molten metal and the slag and casting the molten metal into a massive metal product having a predetermined size and shape. A method for recovering a metal, comprising: 2. The metal recovery method according to claim 1, wherein a plurality of the molds are prepared, and a feeding device for sequentially transporting the plurality of molds in the storage water is provided, and the separation casting process is continuously performed. . 3. The method for recovering metal according to claim 1, wherein the temperature of the stored water is set to 80 ° C. or higher. 4. The depth of the open end of the mold with respect to the surface of the stored water according to a drop between the open end of the mold and the discharge position of the molten product. Metal recovery method. 5. The head between the open end of the mold and the discharge position of the molten product is set to 800 to 1800 mm, and the depth of the open end of the mold relative to the surface of the stored water is set to 50 mm.
The method for recovering a metal according to claim 4, wherein the thickness is set to about 200 mm. 6. A rotary kiln which melts an object and discharges a molten product, and injects the molten product into the mold in the storage water from a discharge end of the rotary kiln. The method for recovering a metal according to any one of the above. 7. The rotary kiln is provided for ironmaking at an ironworks,
The waste generated in the steelmaking process, etc., is treated as an object to be treated. On the upstream side, the object to be treated is heated in a reducing atmosphere to reduce oxides in the object to be treated and to melt the object to be treated. 7. A reduction melting step for obtaining a molten product by the method.
3. The method for recovering a metal according to item 1. 8. A secondary combustion chamber for combusting exhaust gas discharged together with a molten product from the discharge end of the rotary kiln is provided at a discharge end of the rotary kiln, and the water tank and the mold are connected to the secondary combustion chamber. The method for recovering metal according to claim 6, wherein the metal is provided in a state where the metal is substantially isolated from outside air. 9. A water tank storing stored water at a predetermined water level,
Having a mold prepared in the storage water, a molten product containing a molten metal and slag is injected into the mold in the storage water, and in the mold, both the molten metal and the slag A metal recovery apparatus characterized in that molten metal is separated from slag and specific gravity before solidification, and the molten metal is cast into a massive metal product having a predetermined size and shape. 10. The casting machine includes a plurality of the molds, and a feeder for sequentially transporting the plurality of molds in the storage water, and continuously performs the separation casting process.
A metal recovery device according to claim 1. 11. The metal recovery device according to claim 9, wherein the temperature of the stored water is 80 ° C. or higher. 12. The mold according to claim 9, wherein a depth of an open end of the mold with respect to a surface of the stored water is set in accordance with a drop between an open end of the mold and a discharge position of a molten product. Metal recovery equipment. 13. The mold according to claim 1, wherein a difference between an opening end of the casting mold and a discharge position of the molten product is 800 to 1800 mm, and a depth of the opening end with respect to a surface of the stored water is 50 mm.
13. The metal recovery device according to claim 12, wherein the length is set to about 200 mm. 14. A rotary kiln for melting an object to be treated and discharging a molten product, wherein the molten product is injected into the mold in the storage water from a discharge end of the rotary kiln. 14. The metal recovery device according to any one of 9 to 13. 15. The rotary kiln treats waste generated in the iron making and steel making processes of an ironworks as an object to be treated, and heats the object to be treated in a reducing atmosphere on the upstream side thereof. The metal recovery device according to claim 14, wherein a molten product is obtained by reducing an oxide therein and melting an object to be processed. 16. A secondary combustion chamber for combusting exhaust gas discharged from the discharge end together with the molten product from the discharge end of the rotary kiln is provided, and the water tank and the mold are connected to the secondary kiln. The metal recovery device according to claim 14, wherein the metal recovery device is provided in the next combustion chamber in a state where it is substantially isolated from outside air.