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.


Same patents:

FIELD: metallurgy.

SUBSTANCE: method involves preparation of charge, its melting and oxidation of the obtained copper melt. Charge is prepared by classification of copper scrap and its cleaning from tin and lead solder, oxidation of copper melt is performed by batch supply to the melt of NaOH sodium hydroxide in the quantity of 0.5-3 wt % of the charge weight with simultaneous blowdown by means of oxygen-containing gas.

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

3 cl, 1 tbl

FIELD: metallurgy.

SUBSTANCE: solid sodium bromide is loaded in heated vessel, fused salt is pouted on its surface and heated. Molten mix is mixed and discharged from said vessel as-fused. Fused salt is pouted on sodium bromide surface at weight ratio of 1:(0.26-0.30). Said fused salt represents waters of electrolytic production of magnesium and chlorine, say, used electrolyte. Note here that said heated vessel is composed of continuous-action stationary carnallite furnace mixer, furnace hearth being heated to 300-370°C. Fused mix is mixed for 10-15 min. Produced flux may contain the following components at the following ratio: 9-20 wt % of NaBr, 4-9 wt % of MgCl2, 60-70 wt % of KCl, 12-24 wt % of NaCl, 0.7-4.0 wt % of CaCl, and not over 2 wt % of H2O.

EFFECT: higher purity of magnesium or its alloys, reduced formation of slag.

6 cl, 1 ex

FIELD: metallurgy.

SUBSTANCE: flux contains calcium oxide, aluminium oxide, and also partially silicon oxide and magnesium oxide in the form of slags from production of carbonaceous ferrochromium and silicocalcium, the missing magnesium oxide is introduced in the form of baked magnesite, the missing silicon oxide - in the form of quartz sand. At the same time the components are taken at the following ratio, wt %: slag of carbonaceous ferrochrome production 33-35, slag of silicocalcium production 50-52, magnesite 11-15, quartz sand 3-5. At the same time slag of carbonaceous ferrochrome production contains the following components, wt %: silicon oxide 30-35, calcium oxide 4-6, aluminium oxide 20-30, magnesium oxide 30-35, and slag of silicocalcium production contains the following components, wt %: silicon oxide - 30-35, calcium oxide - 63-68, aluminium oxide - 5-10, magnesium oxide - 0-1, calcium fluoride - 2-10.

EFFECT: invention makes it possible to avoid expensive technologies for manufacturing of each components within a flux.

1 tbl

FIELD: metallurgy.

SUBSTANCE: proposed method comprises bismuth fusing. Note here that bismuth is fused with sodium hydroxide flux. Then, metallic sodium or bismuth-sodium addition alloy is introduced into bismuth melt. Amount of sodium or sodium in said bismuth-sodium addition alloy makes 0.1-0.3 wt %. Then, said melt is mixed at 340-360°C. Thereafter, melt cleaned of polonium is settled to remove alkaline fusion cake. Note that said melt is mixed at 340-360°C for 2 to 3 hours while settling is performed for, at least, one hour. Thereafter, melt cleaned of polonium is additionally treated by the mix of sodium hydroxide and sodium nitrate.

EFFECT: higher yield and efficiency.

4 cl, 10 ex

FIELD: metallurgy.

SUBSTANCE: according to the proposed method, aluminium-silicon alloy is first subject to modification by supplying the mixture consisting of chloric and fluoric salts to the molten metal heel; then, after cleaning of molten metal heel from products of their interaction with liquid alloy, which is treated with direct current.

EFFECT: invention allows considerably increasing the duration of action of modification effect for maintaining high mechanical properties of castings.

2 cl, 1 dwg, 1 tbl

FIELD: metallurgy.

SUBSTANCE: procedure for chemical purification of chloride-magnesium melt from impurities consists on pouring magnesium chloride into tanks, in dilution it with electrolyte of magnesium electrolyser, in loading chemical reagent, in mixing and in settling. As chemical reagent there is used calcium oxide at amount of 0.1-1 % of weight of mixture of melted magnesium chloride and electrolyte. Upon settling a clarified part is withdrawn and directed into electrolyser, while a bottom part is directed for utilisation of magnesium chloride.

EFFECT: reduced expenditures for purification.

6 cl, 1 ex

FIELD: metallurgy.

SUBSTANCE: empty ladle is heated to temperature of its lining 800-1600°C. Crushed aluminium and dry salt chosen from a group: barium, potassium, sodium salt or their mixture or their mixture with additives of powders of cryolite and silicate-block are loaded into the ladle. The ladle is subjected to vibration wherein aluminium and salts are mixed and melted, whereupon melted steel is poured into the ladle at maintaining vibration of the ladle. The ladle filled with liquid materials is vibrated during 10-300 seconds. Vibration frequency is increased 1.5-3 times intensifying steel de-oxidation with liquid aluminium and removal of aluminium oxides and non-metallic inclusion from steel as vibration frequency is growing. Further vibration is stopped, slag is removed and de-oxidised and purified from non-metal inclusions metal is teemed in a mould.

EFFECT: raised efficiency of de-oxidation, reduced losses of temperature and fluidity of metal, reduced rejects of produced ingots.

1 ex

FIELD: metallurgy.

SUBSTANCE: invention refers to melted salts for purification of magnesium alloys with efficient removal of impurities and minimal losses of strontium from melt of strontium containing melted magnesium alloy. This melted salt corresponds to double melted salt LiCl-KCl, triple melted salt LiCl-KCl-NaCl or double or triple melted salt containing 20% or less of MgCl2 or CaCl2 from general weight of melted salt. Melted salt in working process can contain 10 wt % or less of impurities.

EFFECT: increased efficiency at production of ingot of strontium containing magnesium alloy.

3 cl, 4 ex, 1 tbl

FIELD: metallurgy.

SUBSTANCE: procedure consists in charging solid salt into heated tank, in pouring melt water-free carnallite on surface of solid salt, in mixing and heating produced mixture, in charging calcium fluoride and in extracting produced flux from tank. As solid salt there is used sodium bromide. Produced melted mixture is stirred with dry compressed air to complete dissolution of sodium bromide. Upon calcium fluoride loading produced melted mixture is again stirred with dry compressed air. Produced flux contains the flowing composition of components, wt %: 20-40 MgCl2, 10-30 NaBr, 2-10 CaF2, 30-35 KCl, 5-10 NaCl.

EFFECT: production of flux of uniform structure due to usage of solid sodium bromide with lower melting temperature instead of barium chloride.

7 cl

FIELD: machine building.

SUBSTANCE: furnace consists of lined jacket with electrodes, and of bell installed inside with charge chamber and central vertical channel, with vertical webbing, overflow channels and bottom between two of ribs and two branches with removable funnels. An orifice of diameter bigger, than diameter of a charging branch and of cross section less, than cross section of the overflow channels in vertical ribs near the charging branch is made in the bottom under the charging branch. The removable charging funnel is ended with a cup-like guide of flow at depth of 0.1-0.5 of height of the bell from its top. Also diameter of the guide is 30-80 mm bigger, than diameter of the end of the charging funnel. Working electrolyte of electrolytic cells is used as heating salt.

EFFECT: simplified furnace maintenance, reduced losses of magnesium and elimination of harmful components from composition of heating salt.

5 cl, 2 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: mixture, consisting of sulphur powder, granules of floatation sulphur pyrite of grade KSF-4 in mixture with broken stone with fraction 20-70 mm or brick crumbs, which are simultaneously agent binding mercury in ionised and neutral forms, taken in ratio 1:9 by weight, and water. After that, mixture is homogenised at rotation rate 20 rev/min, argon is supplied at rate 5.5-6.5 m3/h and then mercury-containing wastes are charged in amount which is at least 50 times less than weight of sulphur powder. Grinding of wastes is carried out to complete binding of metal mercury into water-insoluble compound HgS.

EFFECT: simplification of technology, increase of ecological safety of the process.

2 tbl

FIELD: chemistry.

SUBSTANCE: method includes combined grinding of wastes with sulphur powder and crushing medium in rotary reactor for binding metal mercury into water-insoluble compound. As crushing medium used is sulphur pyrate with fraction 50-150 mm, which is simultaneously agent, binding mercury in ionised and neutral forms. Before combined grinding mixture of sulphur powder, sulphur pyrate and water is preliminarily homogenised, and reactor is filled with nitrogen, supplied at rate 7.5-8.5 m3/h, in amount which is at least 50 times less than weight of sulphur powder. After that mercury-containing wastes are charged and grinding is carried out to complete binding of metal mercury into water-insoluble compound HgS.

EFFECT: simplification of technology and increase of processing process safety.

2 tbl

FIELD: metallurgy.

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EFFECT: reduced consumption of a reducer and content of zinc and lead in a clinker, eliminates softening of material in a furnace.

2 tbl, 2 ex

FIELD: process engineering.

SUBSTANCE: invention relates to extraction of precious metals. Continuous extraction of precious metal composition from raw stock comprises heating of said stock in plasma kiln to produce slag top layer and fused metal bottom layer. Then, slag layer and fused metal layer are removed. Fused metal removed layer is solidified and fragmented for extraction of precious metals from produced fragments. Note here that said raw stock comprises material containing precious metal and collector metal. The latter is either metal or alloy able to form solid solution, alloy or intermetallide compound with one or several precious metals. Proposed device comprises plasma kiln, teeming table for continuous teeming of fused metal pool to form solidified sheet, fragmentation device and separation unit for extraction of precious metals from sheet fragment alloys.

EFFECT: higher yield.

20 cl, 11 dwg, 2 ex

FIELD: ecology.

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EFFECT: increased efficiency and energy saving of recycling luminescent lamps, cost reduction and simplification of disposal technology.

FIELD: metallurgy.

SUBSTANCE: method of pyrometallurgical extraction of silver from secondary lead-bearing stock comprises stock furnacing in two steps. First, lead-bearing stock is furnaced at 1150-1200°C, the melt being cooled to 400°C at the rate of 1950°C/h to 2050°C/h. Then, the melt is heated from 400°C/h to 500°C/h to 1150-1200°C to remove the yellow lead from silver surface.

EFFECT: higher yield of silver.

1 tbl, 3 ex

FIELD: process engineering.

SUBSTANCE: invention relates to cleaning of silver-bearing materials by hydrometallurgy processes, for example, scrap and wastes of microelectronics. Proposed method comprises dilution of silver-bearing material in nitric acid, addition of sodium nitrate to nitrate solution at mixing, extraction of silver salt precipitate and pits treatment to get metal silver. Note here that after addition of sodium nitrate the reaction mix is held for 1 hour to add sodium carbonate or bicarbonate to pulp pH of 8-10. Free silver salt precipitate as silver carbonate is separated from the solution by filtration. Sodium nitrite and carbonate or bicarbonate is added in the dry form. Note here that sodium nitrite is taken with 25% excess of stoichiometry.

EFFECT: higher purity and yield, simplified process.

2 cl, 2 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to hydrometallurgy of scattered elements, particularly, to extraction of bismuth and germanium from secondary stock sources, in particularly, to extraction of bismuth and germanium from oil-abrasive wastes of bismuth orthogermanium crystals production. Proposed method comprises hydrochloride-acid leaching of bismuth and extraction of bismuth from the solution by electrolysis. Said hydrochloride-acid leaching is performed with addition of surfactants to the solution to produce abrasive-germanium-bearing precipitate. Germanium is extracted from said precipitate by distillation of tetrachloride germanium in vapours of hydrochloric acid. Said surfactant represents the commercial mix of oxyethylated alkyl-phenols of commercial grade "АФ" 9-6 at the concentration of 0.01-0.1 wt %.

EFFECT: simplified low-cost process, higher yield.

2 cl, 1 ex

FIELD: metallurgy.

SUBSTANCE: processing method of zinc-containing metallurgical waste involves mixing of waste with coke fines, pelletisation of charge and further performance of a Waelz process in a tube-type furnace. Besides, calcium hydroxide in the amount of 20-30% of silica content in the charge and coke fines with the size of less than 1 mm in the amount of 13-17% of the charge weight are added to the charge at mixing. Charge pelletisation is performed so that granules with the size of 2-4 mm and humidity of 10-12% are obtained. Waelz process treatment is performed at the temperature of 900-1000°C.

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2 cl, 1 dwg, 5 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: method involves separation of a cable into electrical strands in a polymer sheath, steel wire and processing of steel wire pieces into reinforcement elements and with that, separation of steel wire from the electrical strand in the polymer sheath is performed by cutting of steel wire into pieces as a part of the cable along one or two mutually opposite located constituents of the cable by means of adjustable drive disc knives, bending of the cable on rollers and separation of the remained wire pieces from electrical strands by a cutter, and transportation of wire pieces is performed by a vibrating tray with an annular screw-shaped route; deformation of wire pieces is performed by a gear pair having a tooth in the section of a semi-cylindrical shape so that deformation of wire pieces with rollers is provided.

EFFECT: high processing efficiency of wastes of cable products and production of finished products of improved quality, which is suitable for being used in construction of residential and industrial sites.

3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to extraction of metals from water solution. Described are composition for extraction with solvent, which contains orthohydroxyaryloxime extractant, degradation-preventing agent and organic solvent which is not mixed with water. Also described is method of metal extraction from water solution with application of said composition. There exists method of reducing said composition degradation. Orthohydroxyaryloxime extractant is selected from: 5-(C8-C14 alkyl)-2-hydroxyacetophenonoximes, 5-(C8-C14 alkyl)-2-hydroxybenzaldoximes and their mixtures. Degradation-preventing agent represents element of the group, selected from: mono-, di- or tri-(1-phenylethyl)phenol, their mixtures and their isomers.

EFFECT: stabilisation of oximes, which are in contact with nitrate-containing raw material.

31 cl, 3 tbl, 4 ex