Components’ Characterization of End-of-Life Dishwashers

The treatment of Wastes of Electrical and Electronic Equipment (WEEE) is a significant source of secondary raw materials. Ferrous and non-ferrous metals, electronic equipment, and plastics are among these materials. One of the most common metals sourced out of WEEE is stainless steel. Dishwashers are common sources of stainless steel, so large amounts of stainless steel can be recovered from them. In this project, dishwashers were submitted to size reduction via shredding, and the shredded products went through a magnetic separator (which separates all the magnetic ferrous components), an eddy current sensor (which separates all the non-ferrous components) and an induction sorting sensor (which removed all the metallic fractions). This procedure led to the following two streams: one with stainless steel, boards, and cables and another stream mainly including plastic. In the next stage, the stainless-steel stream passed through a high-intensity magnetic separator, leading to a magnetic and a non-magnetic stream. Thereafter, hand sorting was applied to both streams which aimed to increase the recovery from each stream.

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The periclase-chromite refractory decomposition by the action of the pulverized coal and gas medium in course of copper-sulfide raw materials processing

NOVYE OGNEUPORY (NEW REFRACTORIES) ◽

10.17073/1683-4518-2018-12-31-36 ◽

2018 ◽

pp. 31-36

Author(s):

A. M. Klyushnikov ◽

E. N. Selivanov ◽

K. V. Pikulin ◽

V. V. Belyaev ◽

A. B. Lebed' ◽

...

Keyword(s):

Surface Layer ◽

Raw Materials ◽

Weight Percent ◽

Pulverized Coal ◽

Refractory Powder ◽

Ferrous Metals ◽

Composition And Structure ◽

Non Ferrous Metals ◽

Refractory Surface ◽

Gas Medium

The investigating results are given for the periclase-chromite refractories' composition and structure which are in contact with the pulverized coal and gas medium in the coppersulfide smelting furnaces. The high-temperature burnt copper concentrate and the sulfur dioxide gas suspensions combined action changes the surface and deep refractories layers chemical composition, with that the impurities content reach the value in weight percent: Fe 54,0, Cu 7,2, Zn 6,4, S 1,8. The refractory's surface layer saturation with the iron and non-ferrous metals oxides decreases the porosity and gives rise to low-melting compositions and eutectics. The refractory decomposition is induced by the shelling of the refractory surface layers with the filled porous taking place in course of the heating-cooling cycling because of the phase's thermal linear expansion coefficients. When the spent refractory disposal, it is feasible to separate mechanically the surface layer for the non-ferrous metals extracting, the rest part can be used for obtaining the refractory powder of various purpose.

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The Environmentally Friendly Possibility of Using Recycled Plastic from Electrical Waste to Rainwater Detention

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.838.157 ◽

2020 ◽

Vol 838 ◽

pp. 157-163

Author(s):

Eva Pertile ◽

Petr Zamarsky ◽

Petra Tkacova ◽

Miloslava Novosadova

Keyword(s):

Environmentally Friendly ◽

Electronic Equipment ◽

Waste Incinerator ◽

Heterogeneous Mixture ◽

Dynamic Development ◽

Ferrous Metals ◽

Waste Pcbs ◽

Non Ferrous Metals ◽

Constant Improvement

In view of the dynamic development of electrical and electronic equipment and the reduction of its lifetime, the share of electronic equipment that has become waste has risen. In proportion to this situation, there is a constant improvement in separating industrial methods aimed at removing hazardous components of electrical waste (PCBs containing condensers, mercury switches or asbestos insulation). Another commodity, and economically more interesting, is the obtaining of the utility component of the waste iron and non-ferrous metals. After the separation of the interesting components what remains is a heterogeneous mixture of plastic pulp, which is usually landfilled or incinerated in the waste incinerator. This leads to the loss of valuable material, which could be further exploited. The paper deals with the issue of the disposal of plastics from electrical waste and its subsequent use as plastic pulp, which can be used to fill the rainwater detention reservoir.

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The Results of Studying the Technique of Making Golden Horde Products Made of Non-Ferrous Metals (from the Collection of the Volgograd Regional Museum of Local Lore)

Vestnik Volgogradskogo gosudarstvennogo universiteta Serija 4 Istorija Regionovedenie Mezhdunarodnye otnoshenija ◽

10.15688/jvolsu4.2019.1.5 ◽

2019 ◽

pp. 61-74

Author(s):

Kseniya Kovaleva

Keyword(s):

Raw Materials ◽

Secondary Raw Materials ◽

Ferrous Metals ◽

Subsequent Processing ◽

Wide Range ◽

Digital Microscope ◽

Non Ferrous Metals ◽

Group 2 ◽

Large Groups ◽

Cast Products

Introduction. The article is devoted to the results of tracing research of things made of non-ferrous metals from the collections of Tsarevskoe, Vodyanskoe, and Mechetnoe settlements, stored in the funds of the Volgograd regional museum of local lore. Method. The author used the method of tracing. The digital microscope DigiMicro 2.0. was used to record the results of observation. Analysis. The author studied 63 products and allocated two large groups: 1) cast products and 2) forged products. The study fixed the following operations for cast products: the use of open and closed molds, casting in composite forms, casting by the smelted model, by the impression, liner casting. In group 2, the following methods of forging were singled out: forming forging, punching, drawing and forging of wire, bending, drawing, twisting, hacking, cutting. Soldering was used to connect the elements. After forming, most of the products passed the subsequent processing associated with the removal of defects (primarily post-casting) and the application of decor (hammering, engraving, stamping, polishing). In addition, the decor could be formed during the creation of the mold (cast decor). Results. As a result of the study, it was noted the use of a wide range of techniques and operations with a comparative technological simplicity for most products. It was also noticed that a few things have been specially prepared for the processing, and it demonstrates the use of secondary raw materials.

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Assessing possibility of technogenic raw material processing using ultra-low concentrations of sodium cyanide

Proceedings of Irkutsk State Technical University ◽

10.21285/1814-3520-2020-5-1105-1112 ◽

2020 ◽

Vol 24 (5) ◽

pp. 1105-1112

Author(s):

Anastasia Vasilkova ◽

◽

Alexander Byvaltsev ◽

Olga Khmelnitskaya ◽

Grigory Voiloshnikov ◽

...

Keyword(s):

Raw Materials ◽

Sodium Cyanide ◽

Gold Recovery ◽

Raw Material ◽

Ferrous Metals ◽

Low Concentrations ◽

Reagent Consumption ◽

Copper Zinc ◽

Non Ferrous Metals ◽

Technogenic Raw Materials

The purpose of the study is to conduct experiments in order to determine the possibility of technogenic gold-bearing raw material cyanidation using ultra-low concentrations of NaCN. Experiments are carried out on the cyanidation of three samples of technogenic raw materials of different composition. The first sample consists of pyrite cinders (Au - 1.8-2.3 g/t, Ag - 13-22 g/t, Fe - 48.52%, Cu - 0.15-0.30%, Zn - 0.3-0.6%). The second sample is represented by the aged tailings of copper-zinc flotation (sample I) with the content of Au - 0.8 g/t, Ag - 7.0 g/t, Fe - 17.2%, Cu - 0.212%, Zn - 0.207%. The next object is the copper-zinc flotation tailings of a concentration plant (sample II), with the following content of Au - 1.22 g/t, Ag - 15.2 g/t, Cu - 0.13%, Zn - 0.23%. It is recommended to use an aqueous wash from non-ferrous metals with subsequent lime treatment as a preliminary processing of pyrite cinders. Cyanidation is carried out at different consumptions of reagent: from 0.075 to 3 kg/t. The experiments have shown that gold recovery in this range of NaCN consumption varies from 42.9 to 44.2%; moreover, a decrease in the reagent consumption allows to reduce the concentration of non-ferrous metal ions in cyanidation solutions. Before cyanidation sample I has also been subjected to aqueous wash to remove acid and non-ferrous metals. NaCN consumption varies from 0.25 to 2.2 kg/t. In this case the extraction of gold amounts to 36.6-46.4%. Cyanidation of tailings (sample II) is carried out in the range of 0.15-1.2 kg/t of NaCN. Gold recovery varies from 24.1 to 30.9%. The cyanidation technology of technogenic raw materials in the field of ultra-low concentrations of sodium cyanide is promising, since it provides acceptable gold recovery under low reagent consumption. For further research in the field of development of an extraction technology of valuable components, the flotation tailings of copper-zinc production (sample II) are chosen as a promising object. It is planned to carry out semi-industrial tests, calculate technical and economic indicators and develop process regulations.

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Applied WEEE pre-treatment methods: Opportunities to maximizing the recovery of critical metals

Global NEST Journal ◽

10.30955/gnj.002589 ◽

2018 ◽

Vol 20 (4) ◽

pp. 706-711 ◽

Cited By ~ 4

Keyword(s):

Raw Materials ◽

Hazardous Substances ◽

Critical Metals ◽

Treatment Methods ◽

Treatment Processes ◽

Ferrous Metals ◽

General Recommendation ◽

Recovery Treatment ◽

Non Ferrous Metals ◽

Pre Treatment

<p>WEEE is a fast-growing waste stream that includes potentially hazardous substances, but also valuable secondary raw materials, which can be recovered by adequate recycling and recovery treatment. In the last years, the research interest has moved from the conventional recycling (recovery of ferrous and non-ferrous metals, plastic, glass and other “mass relevant” fractions presented in WEEE), to the innovational recycling, aimed to recover trace elements, such as critical metals (CMs) and rare earth elements (REEs). Currently, the majority of CMs and REEs are lost during the pre-treatment processes. In this paper, an overview of the most relevant e-waste categories and products in terms of CMs and REEs presence, a description of currently applied pre-treatment methods and fate of the observed group of metals during pre-processing phase, as well as general recommendation in order to avoid losses of CMs and REEs within the WEEE treatment chain, are elaborated.</p>

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