JP2020093184A - Processing method and processing equipment for metal-containing waste - Google Patents

Abstract

To efficiently recover valuable metal such as gold from metal-containing waste such as urban refuse burned ash and shredder dust.SOLUTION: A processing method for metal-containing waste crushes metal-containing waste, selects from the crushed metal-containing waste by magnetic force, crushes magnetic substances selected by the magnetic force, and selects from the crushed metal-containing waste to recover fine powder. Valuable metal such as gold can be efficiently recovered from fine powder of the magnetic substances from the metal-containing waste without using metal plating remover and the like. In selection from the crushed magnetic substances, magnetic force selection, screening selection or wind power selection can be used. Before crushing the metal-containing waste, metal-containing waste such as shredder dust can be efficiently processed by heating and developing brittleness of the metal-containing waste or by coating a rustproof agent on the magnetic substances.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a method and an apparatus for treating metal-containing waste, and more particularly to a technique for recovering valuable metals such as gold from incineration ash of municipal solid waste, shredder dust and the like.

When recovering valuable metals such as iron from metal-containing waste such as municipal waste incineration ash and shredder dust, the valuable metal is recovered with a magnetic separator after crushing, crushing and crushing the metal-containing waste. Is common (for example, Patent Documents 1 and 2).

Further, in recovering valuable metals such as copper, zinc, iron, and lead from municipal waste, in Patent Document 3, an incinerator for incinerating municipal waste and fly ash generated in the incinerator are washed with water to desalt. Washing desalination equipment and a melting furnace for melting fly ash after desalting by the water washing desalination equipment, the molten fly ash generated in the melting furnace is washed by water washing desalination equipment to desalt, A treatment system for municipal waste that returns a part of the molten fly ash after desalting to the melting furnace is described.

Further, in Patent Document 4, a mill refined powder having a predetermined particle size distribution obtained by crushing raw material waste by a vertical mill and a particle size distribution on a larger diameter side than the predetermined particle size distribution are described. In addition to sorting out the mill stones containing the coarse powder, the milling stones are pulverized and sorted so as to adjust the predetermined particle size distribution of the mill refined powders. A valuable metal recovery method is described in which the value of the valuable metal is adjusted to be higher than the content rate of the valuable metal in the waste.

In addition, in Patent Document 5, incineration ash composed of particle groups classified to have a certain particle size is subjected to specific gravity selection by a dry specific gravity sorter to collect light ash having small specific gravity and heavy ash having large specific gravity. , The heavy ash collected by the specific gravity sorting is put on the moving belt surface of the high magnetic force sorting machine, and the particles containing the non-magnetizable noble metal in the heavy ash are sorted and collected with the particles containing the magnetically attractable metal. Therefore, a method for recovering the precious metal in the incinerated ash with high quality is described.

JP-A-11-57651 JP, 2003-120921, A JP, 2017-189775, A Japanese Patent No. 6375205 JP, 2017-140556, A

However, in the inventions described in Patent Documents 1 to 3, although valuable metals such as iron can be recovered, even the recovery of gold is not considered. Further, in the inventions described in Patent Documents 4 and 5, although non-magnetic particles containing gold can be recovered with high quality, even the recovery of magnetic particles containing gold is not considered.

Furthermore, it is assumed that part of the gold contained in the metal-containing waste is gold plating used in electronic substrates and the like. Therefore, it is conceivable to use a plating remover such as cyanide or sulfuric acid for magnetic substances sorted by a magnetic force sorter or non-magnetic substances that have passed through the magnetic force sorter. Inorganic components other than heavy metals and valuable metals are eluted, making it difficult to treat the waste liquid and reducing the gold recovery rate.

Therefore, the present invention has been made in view of the above problems in the prior art, and an object thereof is to efficiently recover valuable metals such as gold from metal-containing wastes such as municipal waste incineration ash and shredder dust. To do.

In order to achieve the above object, the present invention is a method for treating metal-containing waste, wherein the metal-containing waste is crushed, the crushed metal-containing waste is magnetically selected, and the magnetically-selected waste is selected. It is characterized in that the magnetic substance is crushed, and the crushed magnetic substance is selected to collect fine powder.

According to the present invention, a valuable metal such as gold can be efficiently recovered from a metal-containing waste to a fine powder of a magnetic substance, without using a plating remover or the like.

In the above-mentioned method for treating a metal-containing waste, when selecting the crushed magnetic substance, magnetic force selection, sieve selection or wind power selection can be used.

In addition, in the case of metal-containing waste that cannot efficiently sort valuable metals due to intricate entanglement with combustible components such as resin, heat the metal-containing waste before crushing the metal-containing waste. By embrittlement, valuable metals such as gold can be efficiently recovered from shredder dust and the like.

Furthermore, by coating the magnetic substance with a rusting agent before crushing the magnetic substance, the plating of the valuable metal can be easily peeled off, and the valuable metal can be recovered more efficiently.

The present invention is also a treatment apparatus for metal-containing waste, comprising a first crusher for crushing the metal-containing waste and a magnetic force for magnetically selecting the metal-containing waste crushed by the first crusher. A sorting machine, a second crushing machine for crushing the magnetically-adsorbed material sorted by the magnetic force sorting machine, and a sorting machine for sorting the magnetically-coated material crushed by the second crushing machine into fine powder and coarse powder It is characterized by

According to the present invention, a valuable metal such as gold can be efficiently recovered from a metal-containing waste to a fine powder of a magnetic substance, without using a plating remover or the like.

In the above-mentioned apparatus for treating metal-containing waste, the sorter that sorts the magnetic substance crushed by the second crusher into fine powder and coarse powder may be a magnetic sorter, a sieve sorter, or a wind sorter. ..

Further, a heating device that heats and embrittles the metal-containing waste by heating the metal-containing waste is provided in front of the first crusher, and the metal-containing waste heated and embrittled by the heating device is supplied to the first crusher. By doing so, valuable metals such as gold can be efficiently recovered from metal-containing waste such as shredder dust.

As described above, according to the present invention, valuable metals such as gold can be efficiently recovered from metal-containing waste.

It is a flow chart for explaining one embodiment of the treating method of the metal content waste concerning the present invention.

Next, a mode for carrying out the present invention will be described in detail. In the following description, the case of recovering valuable metal such as gold from ASR (automobile shredder dust) will be described.

FIG. 1 shows an embodiment of a treatment apparatus for metal-containing waste according to the present invention. This treatment apparatus 1 includes a heating furnace 2 for heating ASR at low temperature to embrittle it, and a first for crushing embrittlement. The crusher 3, the wind force sorter 4, the first magnetic force sorter 5, the specific gravity sorter 6 and the second magnetic force sorter 7, which sort the crushed material, the first magnetic force sorter 5 and the second magnetic force sorter 7 sort Sieve sorter 8 for selecting coarse particles from the magnetized material, second crusher 9 for crushing the magnetic material from which coarse particles have been removed, and crushed material by the second crusher 9 for fine powder and coarse powder And a wind screen sorter 10.

The heating furnace 2 is provided for heating the ASR at a low temperature of 250 to 450° C. to make it brittle, and can be a general heating furnace or a cooler extraction duct of cement burning equipment.

When the first crusher 3 is of a cutter type, the blade may be worn due to shearing of the metal waste, or the metal waste may be excessively crushed. When the number is large, vibration may increase and the operation may become unstable. Therefore, it is preferable to use an impact crusher, a hammer crusher, a rotary crusher or a roll crusher.

As the wind force sorters 4 and 10, a zigzag type wind force sorter, an internal circulation type wind force sorter, or the like can be used. As the magnetic force sorters 5 and 7, a permanent magnet type hanging magnetic force sorter, a drum magnetic force sorter, or the like can be used. As the specific gravity sorter 6, a dry type specific gravity sorter such as an air table can be used. A vibration type, a gyro type, a cylindrical rotation type, a wave type and the like can be used for the sieve sorters 8 and 10.

Also, an impact crusher, a hammer crusher, or the like can be used for the second crusher 9.

Next, a method for treating a metal-containing waste by the treatment apparatus 1 having the above configuration will be described with reference to FIG.

First, the ASR is heated at a low temperature in the heating furnace 2, the embrittlement obtained by the low temperature heating is crushed by the first crusher 3, and then the crushed material is sorted by each of the sorting machines 4 to 7, whereby the resin is The main products are light products (brittle products), heavy products containing many valuable metals such as gold, silver and copper, and iron-based magnetic products. The embrittlement selected as a light product can be used as a fuel, and the heavy product can be used as a refining raw material.

Next, after removing coarse particles from the magnetic substances selected by the magnetic force selection by the magnetic force selectors 5 and 7 by the sieve selector 8, the particles are crushed again by the second crusher 9. Finally, the crushed material by the second crusher 9 is sorted into fine powder and coarse powder by the sieve sorter or the wind sorter 10. The fine powder thus obtained contains gold, silver and copper, and iron and the like can be recovered from the coarse powder as in the conventional case.

As described above, according to the present invention, without using a conventional plating remover or the like, a magnetic substance obtained by heating the ASR at a low temperature to embrittle the ASR, and then crushing and selecting twice Valuable metals such as gold can be efficiently recovered by recovering the fine powder of.

In addition, in the said embodiment, although the case where ASR was processed as a metal containing waste was demonstrated, the metal containing waste of municipal waste incineration ash can also be processed. Further, in the case of ASR, embrittlement due to low temperature heating was performed, but when treating other metal-containing waste, it is not always necessary to perform embrittlement due to low temperature heating. The standard for determining that heat embrittlement is necessary is, for example, when the combustible content is 30% or more. Further, the specific arrangement method of the crusher, each sorter, etc., the type of the device, etc. are merely examples, and the present invention is not limited to those described in the embodiments.

Next, a first test example of the present invention will be described.

A comparative example of the magnetic substance itself (present) obtained by crushing the municipal waste incineration ash and magnetically sorting the crushed municipal waste incinerator ash, and crushing this magnetic substance for 5 seconds in a rotary crusher. In Example 1, similarly crushed for 10 seconds was set as Example 2, and the metal content and the metal content ratio of each particle group of each example were measured. The results are shown in Table 1 and Table 2, respectively.

From both tables, the contents of valuable metals (Au, Ag, Cu, Ni) increased in the fine particle groups of 0.5-1 mm and <0.5 mm in both Example 1 and Example 2 as compared with Comparative Example. ing. When Example 2 and Example 1 are compared, Example 2 having a longer crushing time has a higher content rate of valuable metals (Au, Ag, Cu, Ni) in the fine particle group. It is considered that this is because the valuable metal that had been sieve-sorted to 1-4 mm and 4 mm< in the comparative example was separated from the particles of the base material and moved to the fine particle side, and the effect of the present invention was verified. Was done.

Next, a second test example of the present invention will be described.

The above-mentioned municipal waste incineration ash was crushed, and the crushed municipal waste incineration ash was magnetically sorted to apply a rusting agent to the magnetic substance and left for 1 day, then put into a rotary crusher and crushed for 10 seconds. (Rusting + Example 2) as Example 3, the gold content and content ratio of each particle group were measured, and the gold content and content ratio of each particle group in the above Comparative Example and Example 2 were measured. Compared. The results are shown in Table 3 and Table 4, respectively.

From both tables, in Example 3, the content ratio of gold (Au) is significantly increased in the fine particle groups of 0.5-1 mm and <0.5 mm as compared with the comparative example. Further, when compared with Example 2, Example 3 coated with a rust former has a significantly higher gold content in the group of fine particles of <0.5 mm. It is considered that this is because the gold plating was easily separated from the particles of the base material by the rust forming agent, and the effect of the present invention was verified.

The rusting agent is not particularly limited as long as rust occurs on the metal surface, and a halogen-based liquid such as salt water or hydrochloric acid and a halogen-based gas such as hydrogen chloride or chlorine gas are combined. Can be used. To react halogen-based liquids and gases for rusting, the substance containing halogen is reacted with the halogen-based gas by heating the magnetized material, or the heated material is washed with water, etc. There is a method of reacting with a dissolved liquid.

1 Metal-containing waste treatment device 2 Heating furnace 3 First crusher 4 Wind power sorter 5 First magnetic force sorter 6 Specific gravity sorter 7 Second magnetic force sorter 8 Sieve sorter 9 Second crusher 10 Sieve sorter or Wind power sorter

Claims (7)

Crush metal-containing waste,
Magnetically selecting the crushed metal-containing waste,
Crush the magnetic substance selected by the magnetic force selection,
A method for treating a metal-containing waste, characterized by selecting the crushed magnetic substance and collecting fine powder. The method for treating a metal-containing waste according to claim 1, wherein magnetic sorting, sieve sorting, or wind sorting is used in sorting the crushed magnetic deposits. The method for treating a metal-containing waste according to claim 1 or 2, wherein the metal-containing waste is heated and embrittled before the metal-containing waste is crushed. The method for treating a metal-containing waste according to claim 1, 2 or 3, wherein a rusting agent is applied to the magnetic substance before the magnetic substance is crushed. A first crusher for crushing metal-containing waste,
A magnetic force sorter for magnetically sorting the metal-containing waste crushed by the first crusher;
A second crusher for crushing the magnetic deposits selected by the magnetic separator,
An apparatus for treating metal-containing waste, comprising: a sorting machine that sorts the magnetic substance crushed by the second crusher into fine powder and coarse powder. The metal sorter according to claim 5, wherein the sorter that sorts the magnetic substance crushed by the second crusher into fine powder and coarse powder is a magnetic sorter, a sieve sorter, or a wind sorter. Equipment for containing waste. A heating furnace that heats and embrittles the metal-containing waste by heating the metal-containing waste is provided in front of the first crusher, and the metal-containing waste that has been embrittled by heating by the heating furnace is supplied to the first crusher. The apparatus for treating metal-containing waste according to claim 5 or 6, characterized in that.

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