JP2003114178A - Evaluation method for valuable metal-containing waste and recovery method for valuable metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaluation method for valuable metal-containing waste in which a valuable metal is not lost and in which the content of the valuable metal contained in the valuable metal-containing waste is evaluated precisely and to provide a recovery method for the valuable metal in which a control operation is performed easily. SOLUTION: In the evaluation method for the valuable metal-containing waste, the valuable metal-containing waste is dry-distilled and treated in an internal combustion-type dry distillation and gasification furnace, a carbon component is then burned and ashed, its ashed product is then crushed or smashed so as to be mixed, an analytical sample is sampled from its mixture, and the content of the valuable metal is measured. In the recovery method for the valuable metal from the valuable metal-containing waste, the valuable metal-containing waste is dry-distilled and treated in the internal combustion- type dry-distillation and gasification furnace, the carbon component is then burned and ashed, and a valuable-metal component is recovered from its ashed product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for evaluating valuable metal-containing waste and a method for recovering valuable metal. More specifically, the present invention relates to a valuable metal-containing waste contained in valuable metal-containing waste without loss of valuable metal. The present invention relates to a method for evaluating a valuable metal-containing waste whose amount is accurately evaluated, and a method for recovering a valuable metal that is easily controlled.

[0002]

[Prior Art] With the enforcement of the Home Appliance Recycling Law, the discarded home appliances that were conventionally disposed of such as landfill are disassembled and sorted,
Recycling of useful resources contained in abandoned home appliances has started in earnest. Along with this, a large number of printed circuit boards used for waste home appliances and printed circuit boards on which electronic parts are mounted have been sorted, and products having various ICs and LSIs, such as mobile phones and notebook personal computers. Disposal of such items is increasing.

[0003] Conventionally, as a method of recovering valuable metals from a composite material such as a printed circuit board, a printed circuit board on which electronic parts are mounted, or a product in which they are incorporated, these valuable materials are incinerated and valuable metal is removed from incinerated ash. The method of recovering, the method of heating and carbonizing the resin components in these composite materials, the method of separating and recovering valuable metals such as copper, the waste composite material composed of the resin and the metal, to the embrittlement temperature of the resin or lower. Various methods such as a regeneration treatment method are known in which, after cooling and pulverizing, magnetic force is used to separate a portion having a relatively large amount of metal components and a portion having a relatively small amount of resin components.

When these composite materials are incinerated normally, soot is generated, and a part of the valuable metal scatters together with this soot as fine particles, resulting in loss of the valuable metal and environmental problems. Further, in a method of separating a portion having a relatively large amount of metal component and a portion having a relatively small amount of resin component by using magnetic force after crushing, a part of valuable metal is lost while being attached to the resin. Metal loss occurs, and temperature control becomes difficult due to the resin having a high calorific value when melting the metal in the portion where the metal content is relatively large.

Recently, the printed circuit board, the printed circuit board on which electronic parts are mounted, or the products in which they are incorporated have been traded as valuables, not as wastes, so that especially precious metal-containing materials are traded. Trouble with the evaluation has occurred, and it has become a credit problem in transactions. Therefore, in connection with the price when trading for a fee, printed circuit boards, printed circuit boards with electronic components mounted, or products in which they are incorporated (hereinafter referred to as valuable metal-containing waste) contain valuable metals. Evaluation of quantity has become a problem, and A contained in valuable metal-containing waste
There is a demand for an accurate method for evaluating the content of valuable metals such as u, Ag, Pd and Cu.

[0006] The conventional method for evaluating the content of valuable metals contained in waste containing valuable metals is to collect a few% of samples from waste containing valuable metals (reduction sample) and crush the sample. Alternatively, the method of pulverizing after roasting and analyzing the valuable metal content of the sample was the main method. Therefore, the accuracy of the evaluation method was governed by the accuracy of the first sampling, no matter how accurate the subsequent analysis method was.

If only a printed circuit board which is generated as a defective product in the manufacturing process or a printed circuit board on which an electronic component is mounted is used, or if valuable metal-containing wastes of the same kind are used separately, a comparatively single unit is used. Since it is a valuable metal-containing waste, the same result can be obtained no matter how it is sampled, so that it is easy to accurately measure the metal content. However, in valuable metal-containing waste separated from waste home appliances, etc., there are many types of electronic components mounted on printed circuit boards, and each electronic component has a different type of metal and metal content. , The evaluation results differ depending on the sampling, so Au and A contained in those valuable metal-containing wastes
Accurately measuring the content of metals such as g, Pd, and Cu is extremely difficult.

In order to reduce the variation in sampling, it suffices to finely pulverize the whole amount of the valuable metal-containing waste and mix it to obtain a uniform composition before sampling. In reality, it seems that some companies are considering pulverizing the valuable metal-containing waste in the stage before putting it into the furnace, pulverizing it, mixing and sampling it.

[0009]

However, valuable metal-containing wastes also include plastics that constitute substrates, cases, etc. Since these plastics are difficult to break, it is extremely difficult to crush them into small pieces. It is extremely difficult to mix them into a uniform composition and to accurately evaluate the value of the valuable metal content. Further, when a raw material containing a metal component and a plastic component is continuously or intermittently added to the melting furnace, the temperature control of the furnace becomes complicated due to the plastic having a high calorific value.

It is an object of the present invention to provide a method for evaluating valuable metal-containing waste, which has no loss of valuable metal and is accurate in evaluating the content of valuable metal contained in waste. Another object of the present invention is to provide a method for recovering valuable metals that is easy to control.

[0011]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned objects, the present inventors ashed valuable metal-containing waste by a special method and crushed or crushed the ash. The inventors have found that the above objects can be achieved by mixing, mixing, collecting an analytical sample from the mixture, and measuring the valuable metal content, and completed the present invention.

That is, the valuable metal-containing waste evaluation method of the present invention is such that the valuable metal-containing waste is subjected to carbonization treatment in an internal combustion type carbonization gasification furnace, and then the carbon component is burned to incinerate it, and thereafter It is characterized in that the ash is crushed or crushed, mixed, an analytical sample is taken from the mixture, and the valuable metal content is measured.

Further, the method for recovering valuable metal from the valuable metal-containing waste of the present invention is such that the valuable metal-containing waste is subjected to carbonization treatment in an internal combustion type carbonization gasification furnace, and then the carbon component is burned to ash. After that, the ashed product or the ashed product is crushed, and the valuable metal component is recovered from the crushed product.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as a method for performing a carbonization treatment in an internal combustion type carbonization gasification furnace, for example, Japanese Patent Application Laid-Open No.
As disclosed in JP-A-135280 and JP-A-5-296427, valuable metal-containing waste is stored in advance in a gasification furnace having a substantially closed structure.
A method of dry-distilling valuable metal-containing waste by burning part of the valuable metal-containing waste while controlling the amount of inflowing air and thermally decomposing the other part of the valuable metal-containing waste by the combustion heat. Can be adopted. The valuable metal-containing waste can be put into the gasification furnace in its original form without any crushing and crushing. The combustible gas generated by the dry distillation is introduced into a combustion furnace provided outside the gasification furnace and burned.

In this case, the air required for the above-mentioned carbonization is supplied to the gasification furnace, the combustion temperature of the combustible gas in the combustion furnace is detected, and the detected combustion temperature of the combustible gas is substantially constant. It is preferable that the amount of air flowing into the gasification furnace be controlled by performing feedback in accordance with the combustion temperature so that the temperature becomes a predetermined temperature.

Regarding the combustion temperature of the combustible gas in the combustion furnace, the combustible gas generated when a part of the valuable metal-containing waste in the gasification furnace is ignited and the carbonization is started When the combustion temperature of the combustible gas in the combustion furnace gradually rises and then the combustion temperature of the combustible gas reaches a predetermined temperature, the amount of air flowing into the gasification furnace increases. Is controlled so that the temperature is continuously maintained at the predetermined temperature. When the carbonization progresses and the portion of the valuable metal-containing waste that can be carbonized decreases, even if the inflow of air into the gasification furnace is controlled, the amount of combustible gas generated will decrease. The combustion temperature of the combustible gas in the furnace gradually decreases from the predetermined temperature. When about 2 tons of valuable metal-containing waste is stored in a gasification furnace having a substantially closed structure and is subjected to dry distillation, it is preferable to bring this state to about 5 hours.

In the above-mentioned carbonization and combustion treatment,
By appropriately setting the above-mentioned predetermined temperature, it is possible to dry-distill the valuable metal-containing waste while preventing the release of gases such as NO _x which is environmentally unfavorable. Further, by using the combustion heat of the combustible gas in the above combustion furnace as a heat source such as a boiler, the combustion heat of the combustible gas can be effectively used.

By the carbonization treatment as described above, the carbon component as well as the metal component, the ceramic component, the glass component and the like contained in the valuable metal-containing waste remain in the gasification furnace. Therefore, when the amount of combustible gas generated is reduced by the above-mentioned carbonization treatment, the amount of air flowing into the gasification furnace having a substantially closed structure is increased to burn the carbon and incinerate it. In this case, it is not necessary to completely incinerate. Due to this ashing, a part of the carbon component remains along with the metal component, ceramic component, glass component, etc. contained in the valuable metal-containing waste.

At the stage of ashing as described above, the ash is in the form of large and small lumps of various sizes, but since it is fragile, it can be crushed and crushed more easily than the valuable metal-containing waste. Therefore, for accurate evaluation of the valuable metal-containing waste, the ash is crushed, mixed uniformly, and an analytical sample is taken from the mixture to measure the valuable metal content. A well-known measuring method can be adopted for the measurement. In this way, since the ash is crushed, uniformly mixed, and the analytical sample is taken from the mixture, the evaluation of the valuable metal content contained in the valuable metal-containing waste becomes accurate.

When recovering a valuable metal from a valuable metal-containing waste, after the carbonization treatment and the ashing treatment are performed as described above, the ashed products of large and small lumps of various sizes are left as they are.
Alternatively, after crushing or crushing to an appropriate size, it is put in a flash furnace or a converter and treated according to a known technique to recover valuable metals. The dry distillation treatment as described above, the ash obtained by the ashing treatment does not contain an organic combustible material having a high calorific value such as plastic, and also has a small carbon content, so that it can be continuously fed to a flash furnace or a converter. Even if the furnaces are added intermittently, the temperature control of the furnace is easy.

In the practice of the present invention, generally, large and small lumps of various sizes of ash are used as they are, or they are crushed or crushed to an appropriate size and then packed into bags and sent to other factories. According to a known technique, the valuable metal is recovered by putting it in a flash furnace or a converter for processing.

For example, when the above ash is put into a converter of a copper smelting plant, the precious metal is held in the copper. When an anode plate is prepared from copper in which the noble metal is held and electrolyzed using this anode plate, electrolytic copper is deposited on the cathode and decoppered slime containing the noble metal is deposited on the anode side. Next, the decoppered slime is subjected to treatments such as silver concentration and electrolysis at a precious metal factory to remove impurities and be refined.

In the practice of the present invention, it is convenient to treat about 1 to 3 tons of valuable metal-containing waste in a single batch operation, but when simply carrying out the method of evaluating valuable metal-containing waste. It is also possible to treat a small amount of valuable metal-containing waste. Further, in the practice of the present invention, it is preferable to use a printed circuit board, a printed circuit board on which electronic components are mounted, or a product in which they are incorporated as valuable metal-containing waste.

[0024]

EXAMPLES The present invention will be specifically described below based on examples. Example 2 tons of valuable metal-containing waste consisting of a printed circuit board used for waste home electric appliances, a printed circuit board equipped with electronic components, a waste mobile phone, etc., is not crushed and crushed, but in its original form. Put into the dry distillation gasification furnace of the dry distillation gasification incinerator manufactured by Kinsei Sangyo Co., Ltd., while burning a portion of the valuable metal containing waste while adjusting the amount of air to flow in, the waste heat containing valuable metal due to the combustion heat About 25 other parts
Pyrolysis (dry distillation) was carried out at 0 ° C. The flammable gas generated by the dry distillation was introduced into a combustion furnace provided outside the gasification furnace and burned.

The above-mentioned dry distillation is continued for about 5 hours, and when the amount of combustible gas generated is reduced, along with the metal components, ceramic components, glass components, etc. contained in the valuable metal-containing waste in the gasification furnace. A carbon component remained. At this stage, the amount of air flowing into the gasification furnace was increased to burn carbon and ash it. By continuing this operation for 19 hours (from the start of dry distillation to 24 hours), a part of carbon component was left together with the metal component, the ceramic component, the glass component, etc. contained in the valuable metal-containing waste. The total amount of this ash is about 1
It was 500 kg.

At the stage of ashing as described above, the ash was formed into large and small lumps of various sizes, but it was brittle and could be easily crushed and crushed. This pulverized product was uniformly mixed, an analytical sample was taken from the mixture, and the valuable metal content was measured. As a result, about 450 g of Au, about 1500 g of Ag, about 160 g of Pd per ton of ash,
It was about 230 kg of Cu. That is, from about 1 ton of valuable metal-containing waste material, about 338 g of Au, about 1125 g of Ag,
This means that about 120 g of Pd and about 173 kg of Cu were recovered in the ash.

After the carbonization treatment and the ashing treatment were carried out as described above, the ashed products of large and small lumps of various sizes were put into the converter of the copper smelter as they were, and the precious metal was held in the copper. . When an anode plate was prepared from the copper containing the noble metal and electrolyzed using the anode plate, electrolytic copper was deposited on the cathode and decoppered slime containing the noble metal was deposited on the anode side. Next, this decoppered slime was subjected to treatments such as silver concentration and electrolysis at a precious metal factory to remove impurities, and then refined.

[0028]

EFFECTS OF THE INVENTION By carrying out the method for evaluating valuable metal-containing waste of the present invention, it is possible to accurately evaluate the valuable metal content contained in the waste without loss of valuable metal. Control is facilitated by implementing the valuable metal recovery method of the present invention.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C22B 1/00 601 G01N 1/28 T F23G 5/50 B09B 3/00 ZAB G01N 33/20 303Z Z 5 / 00 NF term (reference) 2G052 AA11 AA13 AB01 AB27 AC21 AD12 AD32 AD46 CA48 DA14 EB11 ED04 FB05 FD08 FD16 HA15 HA17 JA08 JA11 2G055 AA05 BA01 CA20 EA04 FA01 FA05 FA06 FA05 FA06 FA24 AC05 AB31 BA05 AC24 AB31 AB02 AB31 AC02 AB31 AB01 AC02 AB31 AB02 AC31 AB02 AC31 AB24 CA44 CB02 CB34 4K001 AA01 AA04 AA09 AA41 BA22 CA01 CA09

Claims (5)

[Claims] 1. A valuable metal-containing waste is subjected to a dry distillation treatment in an internal combustion type dry distillation gasification furnace, and then a carbon component is burned to incinerate, and thereafter the ash is crushed or pulverized and mixed to obtain a mixture thereof. A method of evaluating valuable metal-containing waste, which comprises collecting an analytical sample from the sample and measuring the content of valuable metal. 2. The method for evaluating valuable metal-containing waste according to claim 1, wherein the valuable metal-containing waste is a printed circuit board, a printed circuit board on which electronic components are mounted, or a product in which they are incorporated. 3. A waste metal-containing waste is subjected to a dry distillation treatment in an internal combustion type dry distillation gasification furnace, then a carbon component is burned to ash, and then the valuable metal component is recovered from the ash. A method for recovering valuable metals from waste containing valuable metals. 4. A valuable metal-containing waste is subjected to a dry distillation treatment in an internal combustion type dry distillation gasification furnace, and then a carbon component is burned to ash, and thereafter the ash is crushed, and the valuable metal component is crushed from the crushed product. The method for recovering valuable metal from valuable metal-containing waste according to claim 3, wherein the valuable metal is recovered. 5. The recovery of valuable metal from the valuable metal-containing waste according to claim 3 or 4, wherein the valuable metal-containing waste is a printed circuit board, a printed circuit board on which electronic components are mounted, or a product incorporating them. Method.