JPH08127826A - Treatment of waste material containing copper - Google Patents

Abstract

PURPOSE: To recover a high purity copper with a simple treatment by incorporating copper-containing waste material into a two-step jig, raising the temp. step by step, recovering vaporized component, successively, recovering molten copper and removing the stuck component. CONSTITUTION: The copper-containing waste material is carried into a space part 3 of the two-step jig 2. The space part 3 is closed and evacuated, and organic material in the waste material is vaporized by preheating with a heating means 4 and collected with a condenser 6 and a gas absorber 7 and discharged. The temp. of the space part 3 is further raised to vaporize and recover Zn, and the heating is succeeded to vaporize and recover Pb, etc. Further, the temp. is raised to about 1200 deg.C to recover the copper as dripped molten material. After making granular material by cooling this copper drip, the granule is pulverized to detach carbon, etc., stuck to the copper surface. Successively, the carbon penetrated on the copper grain surface is removed by sending to a grinding process to improve the purity of the copper grain.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to various industrial wastes, in particular, by treating a waste material containing copper to recover valuable materials such as copper and other metal components contained in some cases. The present invention relates to a treatment method that can be collected at the same time. In particular, the present invention is a printed wiring board, a waste motor, and a waste wiring used in various electric devices and electronic devices in which it is difficult to separate the components because it is a complex structure with a chemically stable organic polymer substance. The present invention relates to a treatment method capable of recovering highly pure and expensive copper from a waste such as wood according to a simple treatment process.

[0002]

2. Description of the Related Art A large amount of various electric devices and electronic devices have become widespread with the improvement of living standards and the progress of advanced information society. As a result of the successive introduction of new models of the products into the market, a large amount of old electrical equipment and electronic devices are discarded, which is valuable not only from the disposal problem of industrial waste but also from the viewpoint of global resources. Recovery of the metal component from various parts using the metal component has become a serious problem.

In the past, extremely expensive precious metals such as gold and platinum have been recovered.
For example, for copper and less expensive metals, unless a highly efficient and low-cost recovery method is developed,
At present, it is disposed of as industrial waste.
Currently, as a method of recovering copper components from printed wiring boards, etc., which are discharged in large quantities from discarded personal computers, etc., the boards are finely crushed and treated with hydrochloric acid or sulfuric acid, and copper is converted into chlorides or sulfides for plastic. However, it is not widely used as a commercial method because the method is indirect and the operation is complicated, and wastewater treatment facilities are required.

[0004]

The present invention has been pointed out that the necessity of recovery has been pointed out in the past, but the treatment operation is complicated and must be carried out by a chemical treatment method which itself may be a source of environmental pollution. Therefore, it is necessary to treat chemicals from wastes with a high copper content such as printed wiring boards, waste motors, waste wiring materials used in electrical equipment and electronic equipment whose treatment amount is extremely small compared to waste amount. It is an object of the present invention to provide a simple and inexpensive copper recovery method capable of recovering a copper component according to a clean processing method that does not pollute the environment without adopting a wet processing method. is there.

[0005]

SUMMARY OF THE INVENTION The present invention for achieving the above-mentioned object is basically to heat a copper-containing waste in a closed heating furnace under a vacuum to raise the temperature stepwise and to discard the waste. In addition to destroying the structure consisting of metals and organic substances that make up the object, metals and nonmetals with low vapor pressure are vacuum-sucked as vapor and gas at each temperature step by step vacuum suction to separately collect copper. Relates to a method for treating wastes, which comprises collecting molten copper by finally heating the temperature in the furnace to a temperature above the melting point of copper, cooling and solidifying the molten copper, and collecting the molten copper.

More specifically, according to the present invention, the copper-containing waste is stored in a two-stage jig consisting of a melt receiving portion and a waste storing portion and is introduced into a closed heating furnace, and the inside of the furnace is sucked. Preheating is performed while exhausting, then heating is performed while continuing vacuum suction to raise the temperature of the waste in stages, and the vapor generated at each temperature stage is recovered by the condensing and adsorbing means, and at the final stage waste is collected. Molten copper is collected in the form of droplets in the saucer by raising the temperature above the melting point of copper, and the solidified material is cooled and solidified together with the molten copper in the form of droplets, which remains in the cake-like carbon formed by carbonization of the plastic formed in the storage section. The present invention relates to a method for treating copper-containing waste, which comprises removing the carbon components attached to them after the treatment.

Further, according to the present invention, the molten copper is collected in the form of droplets in a saucer portion and is cooled and solidified together with the droplets of molten copper remaining in the cake-like carbon formed in the storage portion to obtain copper particles. The heat treatment of the copper-containing waste for heating the metal from the furnace through the heating means, the non-oxidizing gas supply means, the high-temperature non-oxidizing gas storage means, the condensing means of the generated metal vapor and the adsorbing means of the non-metal components. The present invention relates to the above-mentioned method for treating copper-containing waste, which is carried out by using a single heat treatment furnace equipped with a vacuum pump for sucking steam and non-metal gas.

Further, according to the present invention, the molten copper is collected in the form of droplets in the pan and cooled and solidified together with the droplets of molten copper remaining in the cake-like carbon formed in the storage portion to obtain copper particles. For the heat treatment of the copper-containing waste for the preheating chamber connected to the vacuum pump and the high temperature non-oxidizing gas storage tank, the preheating chamber is airtightly connected in series, each of which is a condenser and a gas in sequence. Connected to a vacuum pump through an adsorber,
A heating and evaporating chamber directly connected to the preheating chamber, and a plurality of airtightly connected heating and evaporating chambers in which the furnace temperature is sequentially set to a high temperature, and the last of the plurality of heating and evaporating chambers is provided. The heating / evaporating chamber is a heating / evaporating chamber set to a temperature equal to or higher than the melting temperature of the copper component, and the last heating / evaporating chamber has a non-oxidizing gas supply device for cooling and a high-temperature non-oxidizing gas storage tank. Characterized in that the copper-containing waste stored in the two-stage jig is sequentially passed through a series of heat treatment devices in which cooling chambers connected to each of the two are airtightly connected to perform heat treatment. The present invention relates to a method for treating contained waste.

In the present invention, in order to remove the adhered carbon component from the cooled and solidified copper particles, mechanically crushing the solidified copper particles to remove the adhered carbon, and subsequently polishing the surface of the copper particles, In particular, the present invention relates to the above-mentioned method for treating copper-containing waste, which employs a step of polishing using alumina powder as an abrasive.

The present invention also relates to a method for treating copper-containing waste, which comprises pulverizing the copper-containing waste to 1 mesh or less by a pulverizer and then treating it according to the vacuum heat treatment step. .

Further, according to the present invention, the waste is pulverized by a pulverizer into particles in the range of 1 mesh or less to about 50 mesh, and then the main particles are classified by sieving and particles within ± 50% of the particle size of the particles. The present invention relates to a method for treating copper-containing waste, characterized in that a division of copper-containing waste particles consisting of particles having a difference in diameter is obtained, and each division is treated according to the vacuum heat treatment step.

In the above-mentioned processing method of the present invention, the jig for loading the waste base material into the furnace must be of a two-stage type. As described above, the present invention is characterized in that the copper contained in the waste base material is melted and collected, so that the molten copper tray part is separate from the waste base material storage part, and its lower part Need to be installed.

In the present invention, the recovery of the copper component in the waste must be carried out by heating at a temperature above the melting point of copper at the final stage of the heat treatment process of the waste.
The waste is heat-treated step by step, and finally carbonaceous material, that is, carbon, which is a decomposition product of a copper component having a high evaporation temperature and plastic, remains, and this mixture has a melting point of copper.
When heated to 6 ° C. or higher, the copper changes to liquid copper in the form of liquid droplets, and a part of the molten copper with carbon adhering to the surface drops in a spherical shape onto the pan. Further, a part is taken in in the form of droplets in the cake-like carbon formed in the storage portion. This spherical molten copper does not take carbon inside and adheres only to the surface portion, so it can be removed from the surface by mechanical or physical treatment after cooling and solidification, and as a result, carbon-free purity It can be recovered as high copper particles.

According to the treatment method of the present invention, the copper-containing waste can be treated as it is recovered from the waste such as electronic equipment. However, it is preferable to treat the copper-containing waste after crushing it, because the amount of treatment per batch can be increased and the elution of the copper component can be completed quickly. It is also preferable because there is no trouble due to contact with the furnace wall when carrying in the furnace as it is when it is carried into the furnace as it is. When the copper-containing waste is crushed and then treated, it is preferable to crush the copper-containing waste into particles of 1 mesh or less for treatment.

Further, after being pulverized to a range of 1 mesh or less to about 50 mesh, it is classified by classification, which is composed of a mixture of main particles and particles having a particle diameter difference of ± 50% or less from the main particles. It is more preferable to collect the waste particles in advance and treat each of the sections. When the copper-containing waste is pulverized and processed so as to be in the range of 1 mesh or less and 50 mesh or less, the smaller the variation of particles, that is, the narrower the particle size distribution, the final step in the vacuum heat treatment process of the present invention. The particle size of the copper particles obtained from becomes uniform,
Separation from carbon becomes easy and copper particles with high purity can be obtained.

[0016] Waste material has 10 temperature steps for vacuum heat treatment.
When the temperature is about 00 ° C to 1050 ° C, the metal components other than copper are usually evaporated and recovered without heating up to the melting point of copper, and the balance is mostly the copper component and the carbonized carbon component of the organic matter. The objective can be achieved only by collecting. In this type of treatment, the waste is tin (Sn).
This is effective in the case of plated copper wire, for example 105
Since the Sn component is evaporated and recovered by heating to 0 ° C., the balance can be pure copper. However, when the waste contains a large amount of plastics and other metal components, the copper obtained at this stage is a complicated mixture with carbon, and some carbon was incorporated inside the copper. Since it is in a state, copper having a low purity containing carbonaceous matter which cannot be removed by the respective processes of pulverization and polishing performed in the subsequent step for removing carbon from the solidified copper is recovered.

In the present invention, it is important that the heat treatment of the waste be carried out stepwise. The waste to be treated is not limited to the one in which copper is a single metal component,
Since it is common to simultaneously contain components to be metalized, in order to make it possible to separate and recover each of these components at each evaporation temperature stage, the heat treatment is divided into multiple temperature stages and It is necessary to vacuum-evaporate and evaporate and collect the evaporative components for each stage. The present invention has a configuration in which the heat treatment of waste is performed by dividing it into a plurality of temperature stages so that a plurality of kinds of metal components can be recovered, so that a plurality of kinds of wastes are separated for each contained metal component. It is also an important requirement because it is one of the main purposes of the present invention to provide a treatment method capable of indiscriminately performing mixed treatment without any treatment.

The treatment for removing adhered carbon from the spherical solidified copper obtained from the heat treatment step is performed by mechanical crushing treatment and subsequent polishing treatment. The mechanical crushing process is a process of destroying the carbon film adhered to the surface to remove most of the carbon, for example,
It is carried out using a crusher equipped with a stirring blade. The cake-like carbon formed in the storage portion is also crushed by this crushing, and the granular solidified copper taken inside is also recovered.

Most of the surface-adhered carbon is removed by mechanical crushing treatment, and the granular copper particles further contain a small amount of carbon taken into the copper at the surface portion. In order to remove the copper particles, the surface of the copper particles is further polished. The polishing treatment is not particularly limited as long as it is a treatment method capable of grinding the copper grain surface to such an extent that the carbon incorporated in the copper grain surface can be removed, and may be polishing with SiO ₂ particles or the like, In order to efficiently remove only the layer containing carbon existing in a very limited surface area, wet polishing using alumina powder as an abrasive is suitable.

As described above, the copper-containing waste is pulverized into particles in the range of 1 mesh to 50 mesh, and in particular, the pulverized particles are further sieved to obtain the main particles and the particle diameter of the particles ± 50. When the crushed particles are treated by being taken out separately for each classification consisting of a mixture with particles having a particle size difference of less than 100%, the crushed particles do not contain copper in advance. It is possible to efficiently perform specific gravity separation and magnetic separation to remove particles that are not present, and to separate carbon and copper particles extremely well by mechanically pulverizing the carbon-adhered copper particles obtained from the final step. It has been confirmed that copper particles having such a purity that the polishing treatment as described above can be omitted only by removing carbon by crushing treatment have been obtained.

[0021]

Since the above-mentioned waste treatment method of the present invention employs a heat treatment operation in which the waste introduced into the apparatus is raised stepwise, evaporative components are separated and collected at each temperature stage. Therefore, it is possible to accurately separate and collect, for each component, useful metal components and the like contained in each waste even if batch processing is performed without separating multiple types of waste containing multiple components. In particular, by setting the temperature at the final heat treatment step to a temperature equal to or higher than the melting point of copper, it is possible to generate granular molten copper in which carbon exists only in the surface portion and solidify as it is. The removal operation is simple and high-purity copper particles can be recovered.
Further, by subjecting the pulverized waste to a vacuum heating treatment, it is possible to obtain copper particles having a purity that does not require carbon removal treatment by polishing treatment.

[0022]

EXAMPLES Examples of the waste treatment method of the present invention will be described below, but the present invention is not limited to the methods of these examples. FIG. 1 is a schematic view showing an example of a single heat treatment apparatus capable of implementing the waste treatment method of the present invention.

In the figure, reference numeral 1 denotes a heat treatment furnace consisting of a closed container, 2 denotes a jig formed in a two-stage structure having a storage portion for a waste to be treated and a molten metal receiving tray portion, and 3 denotes Space for treating the waste to be treated, 4 is heating means arranged in the space 3, 5 is a door, 6 is a condenser, 7 is a gas adsorber, 8 is a non-oxidizing gas storage tank for preheating. , 9 is a furnace gas stirring fan, 10 is a non-oxidizing gas supply source, 11 is a reducing gas supply source, 12 is a vacuum pump, 13 and 14 are blower pumps, 15, 16, 17, 18, 19, 20 Is a valve,
Reference numerals 21, 23, and 24 denote pipes, 22 denotes a heater-heated pipe, and 25 denotes a gas discharge passage.

A waste base material group including a printed wiring board and the like collected by disassembling various electric devices and electronic devices is stored in the waste base material housing portion of the two-stage jig 2 and the door 5 of the heat treatment furnace 1 is stored. It is opened and loaded into the space 3. When the door 5 is closed, the closed space 3 of the heat treatment furnace 1 is evacuated by the vacuum pump 12 and then heated by the heating means 4. At this time, when the temperature rise rate of the waste base material is slow, the high temperature non-oxidizing gas stored for preheating is introduced under pressure from the high temperature non-oxidizing gas storage tank 8 through the pipe 24 and the valve 16. The valve 16 is closed and the waste substrate is further heated. During this preheating period, the heating gas in the space 3 is agitated by the fan 9 as needed, and the waste base material group is uniformly heated in a short period of time so that each metal is not oxidized to about 100.
The temperature is raised to a temperature of ℃ to 160 ℃.

Preheating under vacuum or under pressure of a non-oxidizing gas for preheating can be stopped to such an extent that a slight evaporation of the valuable component to be recovered in the waste substrate occurs. When the temperature of the waste base material reaches about 150 ° C. to 250 ° C., melting, evaporation, and carbonization of organic substances such as plastics in the insulating paint disposed on the surface of the waste base material and the intermediate layer of the stack occur, and at the same time, the low boiling point metal Since partial vaporization of the class occurs, it is limited to heating to the temperature in the preceding stage.

In the latter half of the preheating period of the waste substrate, the valve 18
The space 3 inside the processing furnace is connected to the vacuum pump 12 through a pipe 22 which is opened and is heated by a heater. The preheated gas inside the space inside the processing furnace is slightly pumped by the pump to the condenser 6 and After being collected by the gas adsorber 7, it is discharged from the discharge passage 25, and the inside of the space 3 is decompressed space (5 ×
10 ⁻² to 1 × 10 ⁻³ Torr).

When the evaporation of the low temperature evaporative components such as plastic has stopped, the temperature is further raised by the heating means to reach about 35
At 0 ° C. (5 × 10 ⁻² to 1 × 10 ⁻³ Torr), an evaporation component such as zinc (Zn) at a medium temperature starts to evaporate, and the condenser 6 recovers Zn and the like. . When evaporation of the evaporation components at a moderate temperature such as Zn is stopped, the temperature of the waste base material group is further increased by heating and reaches about 680 ° C. (5 × 10 ⁻² to 1 × 10 ⁻³ Torr). Components that evaporate in a high temperature range, such as lead (Pb)
And the like start to be evaporated, and Pb and the like are recovered in the condenser.

Further, when the temperature exceeds this temperature and reaches about 1200 ° C., copper (Cu) can be recovered. However, in order to make such a high temperature condition in the furnace, the cost is drastically increased.
Heat only to a moderate extent and collect copper as a melt. As a result of the above-mentioned heat treatment at 1100 ° C., in the case of the treatment of a waste base material whose metal component is mainly copper, such as a printed wiring board, the granular material substantially consisting of copper and carbon is substantially contained in the saucer portion. Collected. Further, a part is collected in a state of being taken into the cake-like carbon in the storage part.

Then, the valve 18 is closed and the valve 1
9 is opened and the non-oxidizing gas for cooling is supplied from the non-oxidizing gas supply source 10 to the inside of the furnace by the pump 13 via the pipe 21 to cool the generated agglomerates and heat the inside of the furnace. The high temperature non-oxidizing gas generated by the exchange is stored in the storage tank 8 as non-oxidizing residual heat gas by the pump 15 from the valve 15. On the other hand, the cooled and solidified spherical object in the pan and the carbon cake in the storage section are taken out of the furnace by opening the door 5. The taken out granular material is in a state in which carbon is adhered to the surface of the granular body substantially made of copper.

Next, the taken out carbon-copper granules and carbon cake are sent to a crushing step (not shown), and the surface-fixed carbon is removed by crushing means such as a crusher equipped with a stirring blade. During the crushing process,
An air flow is passed through the mill, and the carbon components that are separated are discharged outside the mill. Most of the fixed carbon is removed by this mechanical grinding process.

The copper particles from which the surface-adhering carbon has been removed still have a small amount of carbon slightly penetrating into the granular body at the surface portion thereof. Therefore, the copper particles obtained from the crushing step are successively sent to a polishing step (not shown) to remove the surface-penetrating carbon, thereby improving the purity of the copper particles. The polishing treatment is performed by a wet method using fine alumina powder. The copper particles that have undergone this polishing process no longer contain carbon and are extremely high-purity copper particles.

In the above examples, the method of separately collecting various metal components and copper contained in the copper-containing waste base material by raising the temperature in the single vacuum heat treatment furnace stepwise has been described. Next, another embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a schematic of an apparatus with which the method according to the invention can be carried out continuously. The waste substrate 101 is
A preheating chamber 102 connected to the high temperature non-oxidizing gas storage tank 107 by a pipe, a condenser 110 to 112 and a gas adsorbing device 113 to 1 that are connected to the preheating chamber in series in an airtight manner.
15, vacuum pump 117 through valves 125-127
To 119, a plurality of airtightly connected vacuum heating evaporation chambers 103 to 105, and a non-oxidizing gas supply source 1 for cooling which is connected to the vacuum heating evaporation chambers
08 and the high temperature non-oxidizing gas storage tank 107 are processed by using a plurality of airtightly connected processing chambers each including a cooling chamber 106 connected by a pipe.

The waste base material 101 is contained in the upper storage portion of a jig having a two-stage structure, the lower portion of which serves as a melt receiving tray, and is placed on a pressure pusher or a self-propelled roller to preheat the chamber 102.
From (which is also an air displacement chamber), the inside of the apparatus consisting of a series of processing chambers is moved, the processing chambers are sequentially moved, and the final cooling chamber 106 is discharged to outside the processing apparatus. When the jig containing the waste base material enters the preheating chamber 102, the door on the inlet side is closed and the preheating chamber is closed, the vacuum pump 116 is operated to evacuate the heated preheating chamber 102, The environment around the waste substrate becomes non-oxidized, and the waste substrate is preheated to a temperature of, for example, about 50 ° C to 100 ° C.

When it is difficult to uniformly preheat the whole waste material in a short time due to a large amount of introduced waste material, a non-oxidizing gas for preheating is pumped from the storage tank 107 by a pump, and the inside of the preheating chamber is not heated. It is preheated while being stirred by a stirring fan in a pressurized state with an oxidizing gas, the vacuum pump 116 is operated upon completion of the preheat treatment, the non-oxidizing gas in the preheating chamber is discharged, and the inside of the furnace is in a vacuum state. It

Then, the jig comes out from the outlet on the preheating chamber side,
It enters into the first vacuum heat treatment chamber 103 which is air-tightly connected to the preheating chamber and is already in a high temperature and vacuum state (250 ° C., 5 × 10 ⁻² to 1 × 10 ⁻³ Torr) and enters the first vacuum heat treatment chamber. The inlet door is closed and heating is continued, and the vacuum pump 117
Thus, the vapor and gas generated in the first vacuum heat treatment chamber are sucked through the condenser 110, the gas adsorber 113, and the valve 125. Usually, the pipe from the first vacuum heat treatment chamber to the condenser is heated by a heater like the pipe from each vacuum heat treatment chamber to the condenser.

When the steam generation in the first vacuum heat treatment chamber is completed, the jig is sent to the second vacuum heat treatment chamber 104 in a high temperature and vacuum state which is hermetically connected to the first vacuum heat treatment chamber. The second vacuum heat treatment chamber is closed, and the temperature of the waste substrate is raised to the set temperature by heating, and the valve 1
26 is opened, and the vapor and gas generated in the second vacuum heat treatment chamber are continuously collected by the condenser 111 and the gas adsorber 114 by the vacuum pump 118.

When the steam generation in the second vacuum heat treatment chamber is completed, the jig is connected to the second vacuum heat treatment chamber in an airtight state, and the third vacuum heat treatment chamber 105 is in a high temperature and vacuum state.
Sent to The third vacuum heat treatment chamber is closed, and the valve 1
27 is opened, and the steam and gas generated in the third vacuum heat treatment chamber are sucked by the vacuum pump 119 until the temperature of the waste base material reaches the set temperature by heating, and are collected by the condenser 112 and the gas adsorber 115.

If necessary, the evaporation component is collected in the third vacuum heat treatment chamber after heat reduction treatment with a reducing gas such as hydrogen gas supplied from the reducing gas source 109 and further vacuum heating to evaporate the evaporation component. Can also be collected. As described above, when such a reduction treatment is adopted, a metal compound, such as an oxide, is reduced to a simple metal and evaporated and recovered. The heat treatment in this third vacuum heat treatment chamber is the final heat treatment, and the temperature is set to 1100 ° C., which is slightly higher than the melting point of copper, which is the main metal component for recovery. At this temperature, the copper is in a molten state and drops onto the saucer part of the jig as a granular material whose surface is covered with carbon,
A portion of the plastic remains in the form of droplets in the carbonized carbon cake formed of the plastic.

In the third vacuum heat treatment chamber 105, the jig in which the granular molten copper is sampled in the pan and the carbon cake is accommodated in the accommodating portion is then sent from the treatment chamber 105 to the cooling chamber 106 for cooling. Valve 12 from non-oxidizing gas storage tank 108
8. It is cooled and solidified by the non-oxidizing gas supplied by the pump 122. The high-temperature non-oxidizing gas obtained by cooling is sent from the valve 132 to the storage tank 107 for storage, and is used for subsequent residual heat of a new waste substrate. The solidified granular material in the pan that has left the cooling chamber and the carbon cake in the storage portion are then sent to the carbon coating crushing device 133 and crushed. The cooling chamber 106 that has discharged the cooled solidified material is evacuated by the vacuum pump 121 and is prepared for the next batch process.

The crushing device 133 is a crusher capable of crushing and separating the carbon adhered on the surface of the copper particles, and is composed of a crusher equipped with a stirring blade. Here, the adhered carbon covering the surface of the granular molten copper is peeled off by mechanical impact, and is carried out of the mill through the blower pipe 136 by the air flow supplied into the device and collected by the collecting device 135. It

The granular solidified copper discharged from the crushing device 133 is then sent to the polishing device 134. Here, the granular copper solidified product is stirred together with a fine alumina powder mud, and the surface of the copper solidified product is ground to remove carbon penetrating the surface portion. The abrasive is not limited to alumina powder, and SiO ₂ particles or the like which are usually used in this type of polishing treatment can be used, but alumina powder is suitable for the copper particles in the present invention.

Also in the case of the above-mentioned second embodiment, the contents of the metal and non-metal components evaporated and collected in each vacuum heating processing chamber are components that evaporate at the vacuum heating temperature of each processing chamber. The temperature and the degree of vacuum in each vacuum heat treatment chamber are arbitrarily set according to the type of recovery target metal component. Also, the number of processing chambers can be increased or decreased as needed. When the waste to be treated is a base material such as the above-mentioned copper-containing printed wiring board alone, the heat treatment chamber can be reduced to two chambers because the number of kinds of recovered metal components is small.

Further, in the case of the second embodiment, between the preheating chamber and the first vacuum heat treatment chamber, and between each vacuum heat chamber, the outlet of the preceding treatment chamber and the inlet of the succeeding treatment chamber. A buffer chamber that absorbs a temperature difference and a pressure difference between the two chambers is provided between the chambers so that the inlet and outlet of each processing chamber can be connected to each other with improved vacuum sealing performance.

In each of the above embodiments, the processing method for recovering copper from the copper-containing waste has been described. But,
INDUSTRIAL APPLICABILITY The vacuum heat treatment method of the present invention can be applied to the treatment of various metal-containing wastes, etc., only by setting the treatment conditions according to the various metals contained in the waste to be treated, such as aluminum, tin and iron. In the case of empty cans, which are resources such as, for example, a method of crushing the above-mentioned object to be processed to 1 mesh or less in advance and processing the particles with a uniform particle size is a very effective processing method. From blast furnace slag, converter slag, dust collected from electric furnace dust, dust collected from dust collectors, etc. that are by-produced in large quantities in It is a treatment method for converting into slags that can be used as a raw material.

[0045]

As is apparent from the above description, according to the processing method of the present invention, since a complicated processing step has been conventionally required, the recovery of copper-containing industrial waste that is often postponed. Only by applying simple mechanical and physical treatments to the product, it is possible to recover high-purity copper of high commercial value. In addition, the processing cost is low because the processing means basically only employs the usual crushing processing and polishing processing in addition to the simple operation of vacuum heating. Furthermore, since the treatment method does not use chemicals, there is no risk of environmental pollution. In addition, even if there are many types of substrates to be treated, it is a method that can be dealt with by simply setting the temperature in the heating stage to the temperature corresponding to the recovered metal component, so the effect of not requiring a sorting process for the substrates to be treated Is to have.

[Brief description of drawings]

FIG. 1 shows a schematic diagram of a single vacuum heat treatment furnace used in the method of the present invention.

FIG. 2 shows a schematic view of a vacuum heat treatment apparatus having a plurality of treatment chambers used in the method of the present invention and a subsequent crushing treatment and polishing treatment apparatus.

[Explanation of symbols]

1: vacuum heat treatment furnace, 2: waste storage jig, 3: furnace space, 4: heating means, 5: door, 6: condenser, 7: gas adsorber, 8: preheating gas storage tank, 9: Fan, 10: Non-oxidizing gas supply source, 11: Reducing gas supply source, 12: Vacuum pump, 13, 14: Blower pump, 15, 16, 17,
18, 19, 20: valve, 21, 23, 24: pipe, 22: heater heating pipe, 25: exhaust gas discharge passage,
101: waste base material, 102: preheating chamber, 103, 104, 1
05: vacuum heating evaporation chamber, 106: cooling chamber, 107: preheating gas storage tank, 108: non-oxidizing gas supply source, 109: reducing gas supply source, 110, 111, 112: condenser, 1
13, 114, 115: Gas adsorbers, 116, 117,
118, 119: vacuum pump, 121: exhaust pump, 1
20, 122, 123: blower pumps, 124, 125,
126, 127, 128, 129, 130, 131, 1
32: valve, 133: crushing device, 134: polishing device,
135: carbon recovery device, 136: blower pipe.

 ─────────────────────────────────────────────────── ─── Continuation of front page (71) Applicant 594164298 Nissei Steel Industry Co., Ltd. 4533 Tsuboi-cho, Hamamatsu-shi, Shizuoka Prefecture (71) Applicant 593203000 Aoyanagi-shi Son Co., Ltd. 1-12-1 Hiranuma, Nishi-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Yoshiaki Yokoyama 1-1-13-2106 Akamidai, Konosu City, Saitama Prefecture

Claims (7)

[Claims] 1. A copper-containing waste is housed in a two-stage jig consisting of a melt pan and a waste storage area, and introduced into a closed heating furnace. Preheating is performed while suctioning and exhausting the inside of the furnace. Then, the temperature of the waste is raised stepwise by heating while continuing vacuum suction, the vapor generated at each temperature step is recovered by the condensing and adsorbing means, and the waste temperature is set to the melting point of copper or higher at the final temperature step. And change the copper to liquid copper in the form of liquid droplets,
A method for treating copper-containing waste, which comprises cooling and solidifying and then removing adhered carbon components to recover copper particles. 2. The heat treatment of the copper-containing waste for converting the copper into droplet-shaped molten copper and solidifying by cooling to obtain copper particles is performed by heating means, non-oxidizing gas supplying means, high-temperature non-oxidizing property. Use a single heat treatment furnace equipped with a vacuum pump that sucks the metal vapor and the non-metal gas from the furnace through the gas storage means, the condensing means for the generated metal vapor and the adsorbing means for the non-metal component. The method for treating copper-containing waste according to claim 1, characterized in that. 3. The heat treatment of the copper-containing waste for converting the copper into droplet-shaped molten copper and solidifying by cooling to obtain copper particles is connected to a vacuum pump and a high temperature non-oxidizing gas storage tank. The preheating chamber, which is connected to the preheating chamber in an airtight manner in series, and each of which is sequentially connected to the vacuum pump through the condenser and the gas adsorber, and from the heating evaporation chamber which is directly connected to the preheating chamber. And a plurality of airtightly connected heating and evaporating chambers in which the furnace temperature is sequentially set to a high temperature, and the final heating and evaporating chamber of the plurality of heating and evaporating chambers is a temperature equal to or higher than the melting temperature of the copper component. In the last heating and evaporating chamber, the cooling chambers connected to the non-oxidizing gas supply device for cooling and the high-temperature non-oxidizing gas storage tank are hermetically sealed. Stored in the two-stage jig in a series of connected heat treatment devices The method for treating copper-containing waste according to claim 1, wherein the treatment is performed by sequentially passing the copper-containing waste. 4. The step of removing the adhered carbon component from the cooled and solidified copper particles comprises a step of mechanically crushing the solidified copper particles to remove the adhered carbon, and a step of subsequently polishing the surface of the copper particles. The method for treating copper-containing waste according to any one of claims 1 to 3, characterized in that. 5. The method for treating copper-containing waste according to claim 4, wherein the polishing step is a step of using alumina powder as an abrasive. 6. The method for treating copper-containing waste according to any one of claims 1 to 5, wherein the copper-containing waste is pulverized to 1 mesh or less. 7. The copper-containing waste is a classification consisting of a mixture of main particles and particles having a particle size within ± 50% of the particle size obtained by sieving after being pulverized to 1 mesh or less. 7. The method for treating copper-containing waste according to claim 6, wherein: