Electronic waste processing method

FIELD: metallurgy.

SUBSTANCE: electronic waste is crushed on a hammer crusher; crushed copper is added, and then, it is fused in presence of flux during 45-60 minutes at the temperature of 1320-1350°C with air blowdown at its flow rate of 3-4.5 l/h and the obtained slag containing at least 2.6 wt % of precious metals is separated from slag.

EFFECT: effective electronic waste processing with increase of content of precious metals in an alloy.

1 ex

 

The invention relates to the field of recycling of solid waste and can be used in the processing of electronic scrap, mainly printed circuits televisions, calculators, laptops, computers, cell phones, smartphones, and other gadgets and technologies using microelectronic circuits containing precious metals: gold, silver, platinum.

There is a method of processing electronic scrap, including melting of the source material with obtaining alloy electrochemical dissolution of the alloy in acid to obtain a solution or slurry containing gold, processing the obtained products (EN 2090633 C1 IPC C22B 7/00, publ. 20.09.1997 year).

The disadvantage of this method is its lack of effectiveness due to the low content of precious metals in the resulting alloy.

A method of refining scrap electronics products, mainly microelectronic circuits containing precious metals, including grinding scrap, magnetic separation of the ground material, the selection of the nonmagnetic fraction of its magnetic part as a concentrate of precious metals and the use of the magnetic fraction as reagent metallurgical production (EN 2180011 C2, IPC SW 11/02, publ. 27.02.2002,).

The disadvantage of this method is the lack of efficiency of the process p is rerabotka electronic scrap due to the low content of noble metals in the melt.

The method for extracting silver from materials adopted for the prototype, containing silver chloride, traces of gold and platinum group metals, including smelting source material in the presence of fluxes, forming the oxide of the alkali metal, the Department received metallic silver from slag, metallic silver is subjected to melt when loading on the surface of the melt layer of soda ash and melt blowing dry air at a temperature of 1100-1150°C with subsequent granulation (EN 2096506 C1 IPC C22B 11/00, publ. 20.11.1997,).

The disadvantage of this method is the low content of noble metals in the melt during the melting of the source material.

The objective of the proposed method is to increase the efficiency of processing of electronic scrap by increasing to the optimal value content of precious metals obtained after melting of scrap alloy.

The technical result is achieved due to the fact that the method of processing electronic scrap, including the melting of the source material in the presence of fluxes with air purge and separation of the resulting metal from slag, unlike the prototype, the original material in the form of electronic scrap crushed by a hammer mill, to it add the crushed copper, as a flux used: silica - 16%, ash 10%,the glass 15%, lime (8%), Cox - 3%, the melting is carried out at a temperature of 1320-1350°C at a flow rate of air for blowing 3-4,5 liters/h for 45-60 min producing crude copper alloy containing not less than 2.6% of the precious metals.

When the melting of the powdered starting material in the form of electronic scrap with the addition of powdered copper with 25% by weight of the scrap in the presence of a flux: silicon dioxide - 30% by weight of scrap, ash 12%, the glass is 18%, limestone - 10%, coke - 5% and the melting temperature of less than 1320°C by blowing air at the flow rate of 3 l/h for 30 min, the resulting copper alloy containing % (wt.): copper - 88,42, gold, silver - 1,78, the rest of 9.8: iron, lead, aluminum, tin.

Thus, if the failure stated in the way of modes in components of the flux, the melting temperature and air flow to purge the content of noble metals obtained after processing of the alloy is below the optimum, namely: gold, silver is not less than 2.6% and other metals is less than 2%.

Example. Electronic scrap containing: 20% copper, 0.2% silver, 0.02% gold, 0,001% palladium, the rest is plastic, milled to a particle size of 2.5-3.0 mm in a hammer mill equipped with a grill. Then crushed material containing precious metals: gold, silver, palladium, mixed with pre-shredded copper krupno is updated 2-3,5 mm, mass. the share of 25%. The resulting mixture sitout with glucobrassicin additives: silicon dioxide - 16%, soda - 10%glass 15%,lime - 8%, Cox - 3%. The melting of the mixture is conducted in a furnace at a temperature 1320-1350°C with air purge during its consumption, 3-4,5 l/h, for 45-60 minutes

As a result of the melting process is obtained blister copper alloy containing, % (wt.): copper - 95,4; gold, silver - 2.6; the rest of the metals: iron, lead, aluminum, tin - 2,0.

Thus, the melted alloy copper (blister copper), containing the greatest number of noble metals - gold and silver. At the stage of melting is achieved optimum recovery of precious metals from electronic scrap.

A method of processing electronic scrap, including the melting of the source material in the presence of fluxes and air purge and separating the alloy from the slag, characterized in that the starting material is crushed in a hammer mill and add the crushed copper, and as a flux is used (in % by weight of scrap): silicon dioxide - 16, soda - 10, glass - 15, lime - 8 and Cox - 3, while the melting is carried out at a temperature of 1320-1350°C at a flow rate of air for blowing 3-4,5 liters/h for 45-60 min with obtaining copper alloy containing not less than 2.6 wt.% noble metals.



 

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FIELD: metallurgy.

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EFFECT: reduction of content of undesirable impurities in copper scrap melt; improvement of refining degree.

3 cl, 1 tbl

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FIELD: metallurgy.

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1 tbl

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4 cl, 10 ex

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2 cl, 1 dwg, 1 tbl

FIELD: metallurgy.

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6 cl, 1 ex

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1 ex

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3 cl, 4 ex, 1 tbl

FIELD: metallurgy.

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5 cl, 2 dwg, 1 tbl

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2 tbl

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2 tbl

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2 tbl, 2 ex

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1 tbl, 3 ex

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2 cl, 2 ex

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2 cl, 1 dwg, 5 tbl, 5 ex

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3 dwg

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31 cl, 3 tbl, 4 ex

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