JP2001181747A - Treating method for powdery copper scrap by compression and compressed product of powdery copper scrap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treating method for powdery ore copper by compression capable of treating powdery copper scrap by a converter and furthermore to provide a compressed product of powdery copper scrap treatable by a converter. SOLUTION: This method includes a stage (step 1a to 1e) in which powdery copper scrap containing copper of 50% or more, containing moisture of 3 to 5% and graded in such a manner that the maximum size of the grain size is controlled to 10 mm is subjected to compression molding to form a briquette and a stage (step 2) in which the briquette is charged to a converter, by the method the powdery copper scrap is directly treated to form crude copper, and a compressed product of powdery copper scrap obtained in such a manner that a binder is added to powdery copper scrap containing copper of 50% or more, containing moisture of 3 to 5% and graded in such a manner that the maximum size of the grain size is controlled to 10 mm and is molded into an almond shape having the dimensions in which the length is controlled to 25 to 45 mm, and the width is controlled to 50 to 70% of the length under the conditions in which roll supporting pressure by a briquetting machine 10 is 110 to 130 kg/cm2, and the speed of revolution of rolls 11a and 11b is 10 to 14 rpm is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for solidifying powdered copper and a solidified powdered copper, and more particularly, to a method of solidifying powdered copper as a raw material for recycling. And a technique for obtaining blister copper.

[0002]

2. Description of the Related Art First, a schematic flow of copper smelting will be described. The ore as mined from the mine is called "coarse ore" and contains a large amount of valuable materials (gangue) in addition to useful minerals. It is removed as tailings and high-grade concentrate is used for smelting.
Beneficiation depends on the physical or physicochemical properties of the mineral, such as its density,
This is performed by utilizing differences in hardness, magnetism, electrical conductivity, wettability, and the like.

[0003] The concentrate obtained by beneficiation reduces the heat energy used in the smelting process, facilitates the handling of ore supply and transportation to the furnace, and also prevents a decrease in reactivity due to moisture. Drying using heat is performed for the purpose. Drying is performed, for example, using a rotary dryer having the same shape as a rotary kiln having a furnace in the shape of a long cylinder slightly inclined.

[0004] The obtained concentrate is blown into the flash smelting furnace 40 simultaneously with oxygen-enriched air or high-temperature hot air to instantaneously cause a chemical reaction to be separated into mat and slag. As shown in FIG. 4, the flash furnace 40 includes a reaction shaft 41, a settler 43,
The reaction shaft 41 is provided with one to three concentrate burners 47, 47. The concentrate is blown into the furnace from the concentrate burners 47, 47. The flash smelting furnace is characterized by a lower fuel consumption rate than other methods because it utilizes the oxidation reaction heat of the concentrate. Since the heat of oxidation reaction alone may cause a shortage of heat, the concentrate burners 47, 47 assist combustion with heavy oil or the like. The mat obtained here contains 60 to 65% of copper. Since the slag contains about 1% of copper, the slag is smelted in a smelting furnace 49, copper is collected as a mat, and is processed in a converter 50 together with the mat from the flash furnace 40.

[0005] The converter 50 is a cylindrical horizontal type, and is lined with magnesite or chrome magnesite brick, and can be tilted back and forth by an electric motor for convenient charging and discharging (see Fig. 5). A number of tuyeres 57 are provided on the lower side of the side of the furnace.
g / cm ² ) is directly blown into the molten mat. The operation is divided into a slag formation period (sprinkling period) and a copper making period in batches. In the slag formation period, iron in the mat is removed as slag. This slag generation period is repeated two or three times, and after the generated white glue reaches a certain amount, it enters the copper making period to obtain blister copper. The heat source uses the heat of oxidation of sulfides in both the slag generation period and the copper making period, and does not use fuel. In particular, since the reaction heat becomes excessive during the copper making period, anode scrap (electrolytic residue copper) and copper scrap generated during electrolysis are treated. Then, the obtained blister copper is adjusted in S and O in the blister copper in a horizontal tilt type or reverberatory furnace type refining furnace, and then an anode is cast, and high-grade electrolytic copper is obtained by electrolytic refining.

[0006] In the copper smelting process, the processing of powdered copper is performed in order to effectively utilize a powdery recycled raw material containing copper (hereinafter referred to as powdered copper). Since conventional powdery copper processing is powdery, as shown in FIG. 6, it is mixed with the concentrate obtained in the beneficiation process, dried, and used in a flash furnace suitable for processing powdery raw materials. Had been treated by blowing into.

[0007]

However, since the powdered copper contains a large amount of metallic copper, when it is treated in a flash furnace, heat of oxidation reaction cannot be expected unlike copper concentrate. Originally, it is efficient to treat powdered copper as copper scrap during the copper making stage of the converter where the reaction heat becomes excessive. However, if it is charged into the converter as it is, it is in the form of powder and is scattered as dust in the exhaust gas of the converter. For this reason, it has been treated in a flash furnace by mixing with concentrate. In addition, if the powdered copper can be treated without generating dust in the converter, the ore processing amount of the flash smelting furnace can be increased, so that the production can be increased. Further, it is possible to effectively use heat energy during the copper making period and to save fuel in the flash smelting furnace. Then, an object of the present invention is to provide a processing method by solidifying powdered copper which can be processed in a converter. It is another object of the present invention to provide a powdered copper solid that can be processed in a converter by such a processing method.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 contains copper at least 50%, has a water content of 3 to 5%, and has a maximum particle size of 10 mm. Compression molding the powdered copper which has been sized to form a briquette, and charging the briquette into a converter. The present invention provides a treatment method by solidifying powdery late copper.

According to a second aspect of the present invention, there is provided a method for processing copper solidified powder according to the first aspect, wherein the briquette is 25 to 45 m in length.
m, and is formed into an almond shape having a width of 50 to 70% of the length.

According to a third aspect of the present invention, there is provided a process for solidifying powdery copper according to the first or second aspect, wherein the briquetting is performed by a roll supporting pressure of a briquetting machine. 110-130 kg / cm ² , and the number of roll rotation is 10
It is characterized by being molded at １４14 rpm.

According to a fourth aspect of the present invention, there is provided a method for solidifying powdery late copper according to any one of the first to third aspects, wherein the briquette has an increased strength. It is characterized in that a binder for improvement is added.

According to a fifth aspect of the present invention, there is provided a method for solidifying powdery late copper according to the third or fourth aspect, wherein the cluster formed on the outer peripheral surface of the roll of the briquetter. It is characterized in that a lubricant is sprayed on the pocket, which is the parent form of the ore, in order to enhance its releasability.

[0013] In order to solve the above-mentioned problems, the invention according to claim 6 is a powder containing at least 50% of copper, having a moisture content of 3 to 5%, and having a maximum particle size of 10 mm. A binder for improving the strength is added to the copper, and the roll supporting pressure by the briquetter is set to 110 to 130 kg.
/ Cm ² , the roll rotation speed is 10 to 14 rpm, the shape is 25 to 45 mm in length, and the width is 50 to the above length.
The present invention provides a powdered latex solidified material characterized by being formed into an almond shape having a size of about 70%.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of a method for solidifying powdered copper waste and a preferred embodiment of a solidified copper powdered material according to the present invention will be described in detail with reference to the drawings. Here, FIG. 1 is a flowchart of an embodiment of a processing method by solidifying powdery late copper according to the present invention. First, powdered copper differs in its composition as well as its copper content depending on the cause of its generation. Here, Table 1 shows various components of the powdery late copper.

[Table 1] Since it is problematic to treat powdery copper having a low copper content in a converter, it is preferable to adjust the copper content to be at least 50% or more. For example, when treating powdery copper having a low copper content, the copper content is reduced by mixing at a predetermined ratio with powdery copper having a high copper content.
It is adjusted so as to be 0% or more (step 1a). Of course, powdery copper having a copper content of more than 50% can be used without being mixed.

The water content of the powdered copper is as low as 1%
Some are less than 30% and some are less than 30%.
If there is a large amount of water, the water may ooze out during compression molding and cause molding failure. Therefore, it is necessary to adjust the water content of the powdered copper to 3 to 5% in order to prevent this (step 1).
b). For adjusting the water content, for example, a rotary drier having the same shape as the rotary kiln described above may be used, or powdery copper may be placed on a wire mesh or a perforated plate to send hot air to dry.
In addition, it can also be made by solar drying.

Further, when the powdered copper is subjected to compression molding, if the particle size exceeds 10 mm, the moldability deteriorates, and the compression molding becomes difficult. Therefore, the powdered copper, which has been dried and adjusted for the water content, is passed through a 10 mm × 10 mm mesh, and sieved into one having a maximum particle size of 10 mm and one having a larger particle size. Sizing (Step 1)
c) Use the one adjusted so that the maximum particle size is 10 mm. Incidentally, powdered copper having a particle size exceeding 10 mm can be directly processed in a converter without molding into briquette. In general, it is considered that a material having a wide particle size distribution capable of obtaining closest packing has better moldability than a material having a uniform particle size distribution with little difference in particle size.

In the case where it is difficult to obtain a strong briquette by only the compressive force of the briquetter 10 (see FIG. 2), or to reduce friction with the rolls 11a and 11b of the briquetter 10, the binder is added to the powdery copper. Is added (step 1d). Binders are classified into powdery and liquid types, and are roughly classified into the following three types according to the difference in their effects. Matrix system: The binder fills the voids of the powdery copper and strongly bonds between the particles. Film system: The surface of the powdery copper is covered with a thin film of the binder (liquid), and the particles are bonded by the adhesive force of the binder. , Which increases the strength by drying after molding Reactive system: Due to the binding effect based on the chemical reaction between the binder or the binder and the powdered copper When using the binder, thoroughly mix the powdered copper before molding Need to be done. In particular, a liquid binder is used to completely adhere to the particle surface.
Mixing with an Irish mixer or the like is necessary. When a liquid binder is used, it is necessary to pay attention to the water content of the copper powder.

The matrix binder includes, for example, coal tar pitch, paraffin, asphalt, wax, portland cement, sugar, clay, starch and the like. Examples of the film binder include water, pulp waste liquid, pitch emulsion, bendite, water glass (sodium silicate), molasses, glue, starch, sucrose, and PVC.
(Polyvinyl alcohol) and CMCNa (sodium carboxymethylcellulose). Further, the reaction system binder includes, for example, Ca (OH) ₂ , Ca (OH)
₂ + molasses, sodium silicate + CaCl ₂ , MgO + M
gCl ₂ , MgO + Fe ₃ O ₄ , sodium silicate + C
O ₂ or the like is there. The use of water glass is preferable in consideration of the fact that the binder to be used is inorganic, costs and the like. Also, the larger the amount of water glass added, the more the molding strength tends to increase. However, if the amount added is 6% or more, a phenomenon occurs in which the formed briquette breaks into layers when discharged from the rolls. It is considered that 2 to 4% is appropriate.

Next, the adjusted copper powder was removed from the briquetter 1
0 to form a briquette (step 1e). The briquetter 10, as shown in FIG. 2, is provided with two rolls 11a and 11b which are close to each other and rotate at the same speed in opposite directions, and for supplying powdery copper to a gap between the rolls 11a and 11b. It has a hopper 15 and a belt conveyor 17 for transporting the formed briquette. Roll 11
The bearing that supports a is supported from behind by a hydraulic cylinder 19, and the other roll 11 b is supported by a frame 10 a of the briquetter 10. Hydraulic cylinder 19 is connected to the accumulator 19a encapsulating inert gas or N ₂ gas, roll 11a by the gas pressure in the accumulator 19a, holds the molding pressure between 11b constant, the roll 11a at the time of overload or contamination Retreats to protect the machine body. Note that a spring using a spring instead of the hydraulic cylinder 19 can also be used.

A screw 15a is provided inside the hopper 15, and the screw 15a removes air contained in the powdery copper contained in the hopper 15 from the supply port 15b to increase the density of the roll. 11a, 1
Sent between 1b. A large number of pockets 13 are formed on the surfaces of the rolls 11a and 11b, which are a matrix of a molded product, and are formed into a predetermined shape by rotation of the rolls 11a and 11b. As shown in FIG. 3, the shape of the pockets 13 is, for example, an almond shape (FIG. 3A), a pillow shape (FIG. 3B), a lens shape (FIG. 3C), and a finger shape. (FIG. 3D).
Then, the formed briquette is conveyed by the belt conveyor 17.

Although the speed at the outer peripheral ends of the rolls 11a and 11b and the moving speed of the briquette are the same, the peripheral speeds at the bottoms of the pockets 13 and 13 and the outer peripheral ends of the rolls 11a and 11b are different. , 13 between the surfaces. Therefore, the shape of the pockets 13, 13 is such that the pockets 13, 13 are formed by continuous curved surfaces in the circumferential direction,
In addition, the shape is required to have a small frictional resistance due to slippage.

The pillow shape has the same thickness at the center portion and the end portion, and has an acute angle at the end portion, so that the frictional resistance is increased and the peelability from the pockets 13 is affected. On the other hand, the shape of the pockets 13 is preferably an almond shape because the almond shape has such a low frictional resistance and good releasability. In addition, if the size of the briquette is too large, a large compressive force is required, and handling of the briquette becomes inconvenient, so its shape is 25 to 45 mm in length,
Preferably, the width is 50 to 70% of the length.

The surface of the rolls 11a and 11b, especially the pockets 13 and 13, are slipped to reduce the resistance due to the internal friction of the powdered copper and the friction between the copper and the surfaces of the rolls 11a and 11b to enhance the molding effect. It is effective to apply a lubricant. Liquid lubricants include, for example, water, ethylene glycol, lubricating oil, glycerin, silicone, and the like; solid lubricants include, for example, talc, magnesium stearate, graphite, paraffin, stearic acid, wax, Molybdenum disulfide and the like. Some binders also have a lubricating effect.
When a liquid lubricant is used, it is necessary to pay attention to the water content of the powdered copper as described above.

On the other hand, the rotation speed of the rolls 11a and 11b is
This is an important factor in determining the processing amount because the number of rotations per time increases as the number of rotations per hour increases, but the speed must be suitable for the powder compression process. Table 2 shows the results of tests performed using a briquetting machine to obtain the optimum rotation speed.

[Table 2] As a result, no remarkable difference was found in the yield and the crushing strength between 6.1 rpm and 12.1 rpm. In addition, the rotation speed of the rolls 11a and 11b can be increased by increasing the degassing and bulk density of the powdered copper by the screw 15a. However, if the number of rotations is too high, the compressive force does not propagate to the inside of the copper powder, so that the crushing strength is rather reduced. Therefore, considering that the processing amount increases as the number of rotations per time increases, the roll 11a,
It is considered that the rotation speed of 11b is preferably 10 to 14 rpm. Of course, the rotation speed is not limited to this range.

As shown in Table 3, the roll supporting pressure was 120 kg / cm ² and 170 kg / cm ^2.
A compression molding test was performed at a pressure of The drop strength was measured by dropping 10 briquettes obtained by molding under the same pressure onto a concrete floor from a height of 2 m, and the number of breaks and the rate of breakage of 30
% And a residual rate of +9.5 m.
As a result, the roll supporting pressure became 120 kg / cm ² and 1
In the case of 70 kg / cm ^2, no remarkable difference was observed. Therefore, the power consumption of the briquetters is low,
It is considered preferable to operate at 30 kg / cm ² . Of course, a higher pressure, for example, 170 kg /
Needless to say, there is no problem even if compression is performed in cm ² .

[Table 3]

Here, the operation of the briquetter 10 will be briefly described. The powdery copper that has been charged into the hopper 15 from the supply port 15b is supplied to the gap between the rolls 11a and 11b while being stirred and degassed by the screw 15a. Then, the powdery copper is filled in the pockets 13 and 13 which are formed into a matrix so that the briquettes become almond-shaped on the surfaces of the rotating rolls 11a and 11b. A lubricant is applied to the surfaces of the rolls 11a and 11b (particularly, the pockets 13 and 13) in advance, and the releasability is improved. Roll 11
As a and 11b rotate further, the powdered copper is compressed and becomes an almond-shaped briquette.

The briquette thus obtained is charged from a charging port 53 provided on the side of the hood 51 of the converter 50 in operation (step 2). Therefore, since the operation of tilting the converter 50 and opening the hood 51 is not necessary, the converter 50 can be charged into the converter 50 even during air blowing, and the operation of the converter 50 is not hindered. Can be operated without reducing production capacity.

[0028]

According to the present invention, powdery copper can be directly processed as copper (copper scrap) in a converter, so that the ore processing amount can be increased in a flash smelting furnace and the production can be increased. This has the effect of becoming In addition, by treating powdered copper as copper scrap during the copper making stage of the converter where the reaction heat becomes excessive, it is possible to effectively utilize heat energy and reduce the fuel consumption of the flash smelting furnace. Have. further,
The powdered copper is compacted into briquettes and charged into the converter, which has the effect that the powdered copper can be treated without being scattered as dust in the exhaust gas from the converter, and hinders the operation of the converter. Without reducing the production capacity of the converter.

[Brief description of the drawings]

FIG. 1 is a flowchart of an embodiment of a processing method for solidifying powdery late copper according to the present invention.

FIG. 2 is a longitudinal sectional view of the briquetter.

3A and 3B are perspective views showing shapes of briquettes, wherein FIG. 3A shows an almond shape, FIG. 3B shows a pillow shape, FIG.
(D) shows a finger shape.

FIG. 4 is a vertical sectional view of a flash smelting furnace.

5A is a front view of a converter, and FIG. 5B is a side view of the converter.

FIG. 6 is a flowchart of conventional powdery copper processing.

[Description of Signs] 10 Gang Machine 10a Frame 11a Roll 11b Roll 13 Pocket 15 Hopper 15a Screw 15b Supply Port 17 Belt Conveyor 19 Hydraulic Cylinder 19a Accumulator 40 Self-Flux Furnace 50 Converter

Claims (6)

[Claims] 1. The method according to claim 1, wherein the copper content is at least 50% and the water content is 3 to 5%.
% And a step of compressing and molding the powdered copper sized to have a maximum particle size of 10 mm to give a briquette, and a step of putting the briquette into a converter. A process for solidifying the powdered copper, wherein the powdered copper is directly processed into blister copper. 2. The processing method according to claim 1, wherein the briquette has a shape having a length of 25 to 45 mm and a width of 50 to 70% of the length. A process for solidifying powdery late copper, characterized in that it is shaped into almonds of a size. 3. The processing method according to claim 1, wherein the solidified copper powder has a roll supporting pressure of 110 to 130 for the briquetting machine.
A method of solidifying copper powder, which is formed at a roll speed of 10 to 14 rpm at Kg / cm ² . 4. The treatment method according to claim 1, wherein the binder is added with a binder for improving the strength thereof. Characteristic treatment method by solidifying powdery late copper. 5. The processing method according to claim 3, wherein solidification of the powdery late copper is carried out. The pocket which is formed on the outer peripheral surface of the roll of the briquetter and which is a matrix of the briquette is releasable. A method for solidifying powdery late copper, which comprises spraying a lubricant to increase the solidification. 6. Copper containing not less than 50% and a water content of 3 to 5%.
% So that the maximum size of the particle size is 10 mm
Binder to improve the strength of powdered copper
, And the roll supporting pressure by the briquetter is 110 to 13
0Kg / cm ²The roll rotation speed is 10 to 14 rpm.
Under the condition, the shape is 25-45 mm in length and the width is the length
Molded into almonds 50-70% of the size
A solidified powder of late copper, characterized in that: