Recovery of Zinc from the Concentrate of Domestic Waste Processing by Vacuum Distillation

The heterogeneity and local distribution of elements are established as a result of the study of nonferrous metals distribution and the composition of domestic wastes processing concentrate containing 20–40% copper, 40–50% brass, 20–28% zinc and up to 1% aluminium. Metals are mainly concentrated in granules of three types: zinc-based, copper-based and copper–zinc alloy, i.e., brass. The phase composition of these granule types and their structure are determined. Zinc granules are covered with a refractory oxide shell. A distillation processing method for such raw materials based on full state diagrams, including the phase transition of melting pairs of double systems of copper and tin with zinc and lead, is offered. The possibility of a rather complete zinc distillation (over 90%) with the accumulation of other metals in the copper-based alloy, containing more than 96 wt. % of the basic element, has been demonstrated by electric crucible melting in a highly reducing atmosphere. Copper-based alloys, after adjustment for the content of some metals (tin), can be realized as pressure-treated tin bronzes. Copper with the content of impurities corresponding to the standard for blister copper can be electrolytically processed (after dissolution in sulphuric acid) in copper production. Equipment for the implementation of the electro-thermal processing process that provides metal recycling of the metal concentrate is proposed

Recovery of Zinc from the Concentrate of Domestic Waste Processing by Vacuum Distillation

The heterogeneity and local distribution of elements are established as a result of the study of nonferrous metals distribution and the composition of domestic wastes processing concentrate containing 20–40% copper, 40–50% brass, 20–28% zinc and up to 1% aluminium. Metals are mainly concentrated in granules of three types: zinc-based, copper-based and copper–zinc alloy, i.e., brass. The phase composition of these granule types and their structure are determined. Zinc granules are covered with a refractory oxide shell. A distillation processing method for such raw materials based on full state diagrams, including the phase transition of melting pairs of double systems of copper and tin with zinc and lead, is offered. The possibility of a rather complete zinc distillation (over 90%) with the accumulation of other metals in the copper-based alloy, containing more than 96 wt. % of the basic element, has been demonstrated by electric crucible melting in a highly reducing atmosphere. Copper-based alloys, after adjustment for the content of some metals (tin), can be realized as pressure-treated tin bronzes. Copper with the content of impurities corresponding to the standard for blister copper can be electrolytically processed (after dissolution in sulphuric acid) in copper production. Equipment for the implementation of the electro-thermal processing process that provides metal recycling of the metal concentrate is proposed

On the Distillation Separation of Aluminum–Tellurium System Melts under Equilibrium Condition

The problem to purify secondary aluminum raw materials from tellurium can be solved by the distillation method based on phase diagrams with liquid and vapor coexistence fields. Similar diagrams can be generated based on the vapor pressure values of the components. In this regard, the vapor pressure values of tellurium and aluminum telluride were determined by the boiling point method. The aluminum vapor pressure values are found by integration of the Gibbs-Duhem equation. The boundaries of the system vapor-liquid equilibrium fields for the Al-Te system at 101.32 kPa and 6.67 kPa were calculated based on the vapor pressure values of the components. The following conclusion can be made from the consideration of the position of the liquid and vapor coexistence field boundaries under atmospheric pressure and in a vacuum. Aluminum can be quite completely purified from Al2Te3 and Te by distillation in a vacuum in one operation at temperatures above 1273 K. Tellurium will be in a complete vapor state under these conditions—above the boiling line in the Al2Te3-Te system

On the Distillation Separation of Aluminum–Tellurium System Melts under Equilibrium Condition

The problem to purify secondary aluminum raw materials from tellurium can be solved by the distillation method based on phase diagrams with liquid and vapor coexistence fields. Similar diagrams can be generated based on the vapor pressure values of the components. In this regard, the vapor pressure values of tellurium and aluminum telluride were determined by the boiling point method. The aluminum vapor pressure values are found by integration of the Gibbs-Duhem equation. The boundaries of the system vapor-liquid equilibrium fields for the Al-Te system at 101.32 kPa and 6.67 kPa were calculated based on the vapor pressure values of the components. The following conclusion can be made from the consideration of the position of the liquid and vapor coexistence field boundaries under atmospheric pressure and in a vacuum. Aluminum can be quite completely purified from Al2Te3 and Te by distillation in a vacuum in one operation at temperatures above 1273 K. Tellurium will be in a complete vapor state under these conditions—above the boiling line in the Al2Te3-Te system

Phase Transformations and Tellurium Recovery from Technical Copper Telluride by Oxidative-Distillate Roasting at 0.67 kPa

This paper presents the results of a study of phase transformations occurring in copper-telluride by-products during its processing of oxidation-distillate roasting at low pressure. The results show that copper telluride is oxidized through intermediate compounds to the most stable tellurate (Cu3TeO6) at low temperatures. The increase in the roasting temperature above 900 °C and the presence of an oxidizer favor the copper orthotellurate decomposition. Thus, the tellurium extraction rate is 90–93% at a temperature of 1000 °C, the oxidant flow rate is 2.2 × 10−2 m3/m2·s, and the roasting time is 60–90 min. One of the decomposition products is copper oxide alloy, which is the basis of the residue. The second product is tellurium in oxide form, which evaporates and then condenses in the cold zone of the condenser in crystalline form. The main constituent phase of the condensate is tellurium oxide (TeO2), which can be further processed during one operation to elemental chalcogen by thermal reduction or electrolytic method

Dearsenation of Gold-Bearing Composite Concentrates without Forced Displacement in a Sublimator

The primary devices for extracting volatile components from dispersed materials in a vacuum are devices with the movement of raw materials by directed vibrations. During the analysis of the operation of such installations, some shortcomings were identified, due to the supply of heat flow to the processed raw material and the requirements for the choice of structural materials. In this article, the authors tested a heating method and a design of a sublimator with the supply of heat flow to the dispersed material by radiation from the heater. The sublimation zone is made in the form of a shaft formed by simple-shaped plates, the design and material of which involve the use of refractory and ceramic materials that are inert with respect to an aggressive vaporous sulfide medium. The movement of bulk material through the volume of the sublimator occurs due to rheological properties: sliding along inclined plates. Technological tests on the sublimation of arsenic sulfides from gravity and flotation composite concentrates of the Bakyrchik deposit (Kazakhstan) have shown the possibility of a high degree of sublimation of arsenic (more than 96–99%) while preserving precious metal composites in the sublimation residue and stable operation of equipment. Sublimation residues containing 0.14–0.30% As can be processed by known methods. The possibility of sufficiently complete removal of arsenic and its compounds from composite concentrates at a reduced pressure with the removal of the latter in the most environmentally friendly sulfide form has been established

Vacuum-Distillation Extraction of Selenium from Selenium-Containing Preliminary Products and Materials

Результаты многолетних исследований коллектива лаборатории вакуумных процессов АО «Институт металлургии и обогащения» легли в основу разработки экологически безопасной вакуум-дистилляционной технологии извлечения селена из различных селенсодержащих промпродуктов и материалов с последующим его рафинированием до марочного состояния в соответствии с ГОСТ 10298-79. Технология и аппаратура апробированы на многих видах материалов, в том числе на техническом и черновом селене, производимом ТОО «Казцинк» и ТОО «Корпорация Казахмыс», селенсодержащих пылях рукавных фильтров аффинажного производства и шламах сернокислотного производства ТОО «Корпорация Казахмыс», шламах никелевого производства ГМК «Кольская», селенсодержащих концентратах ОАО «Красцветмет». В данной работе на примере нескольких видов материалов показана эффективность разработанной вакуум-дистилляционной технологии и аппаратуры, позволяющих получать в одну стадию дешёвым безреагентным способом марочный селен с содержанием более 99,5 % основного компонентаThe results of long standing studies by collective of the laboratory of vacuum processes JSC “Institute of Metallurgy and Ore Benefication” provided the basis for the development of environmentally friendly vacuum-distillation technology of selenium extract from the various selenium-containing middling products and materials with further refinement to the slate condition in accordance with GOST 10298-79. The technology and equipment has been tested on different raw materials, including: technical and crude selenium produced by Kazzink LLP and Kazakhmys Corporation LLP, selenium-containing bag filter fumes of refinery production and drilling cutting of sulfuric production produced by Kazakhmys Corporation LLP, sludge of nickel production produced by Kolsky MMC, selenium-containing concentrates Krastsvetmet JSC. Potential of developed vacuum-distillation technology and equipment, allowing to receiving the selenium containing more than 99.5 % of the main component within one step by cheap reagentless method, is shown in this article an example of several form of material

Vacuum-Distillation Extraction of Selenium from Selenium-Containing Preliminary Products and Materials

Результаты многолетних исследований коллектива лаборатории вакуумных процессов АО «Институт металлургии и обогащения» легли в основу разработки экологически безопасной вакуум-дистилляционной технологии извлечения селена из различных селенсодержащих промпродуктов и материалов с последующим его рафинированием до марочного состояния в соответствии с ГОСТ 10298-79. Технология и аппаратура апробированы на многих видах материалов, в том числе на техническом и черновом селене, производимом ТОО «Казцинк» и ТОО «Корпорация Казахмыс», селенсодержащих пылях рукавных фильтров аффинажного производства и шламах сернокислотного производства ТОО «Корпорация Казахмыс», шламах никелевого производства ГМК «Кольская», селенсодержащих концентратах ОАО «Красцветмет». В данной работе на примере нескольких видов материалов показана эффективность разработанной вакуум-дистилляционной технологии и аппаратуры, позволяющих получать в одну стадию дешёвым безреагентным способом марочный селен с содержанием более 99,5 % основного компонентаThe results of long standing studies by collective of the laboratory of vacuum processes JSC “Institute of Metallurgy and Ore Benefication” provided the basis for the development of environmentally friendly vacuum-distillation technology of selenium extract from the various selenium-containing middling products and materials with further refinement to the slate condition in accordance with GOST 10298-79. The technology and equipment has been tested on different raw materials, including: technical and crude selenium produced by Kazzink LLP and Kazakhmys Corporation LLP, selenium-containing bag filter fumes of refinery production and drilling cutting of sulfuric production produced by Kazakhmys Corporation LLP, sludge of nickel production produced by Kolsky MMC, selenium-containing concentrates Krastsvetmet JSC. Potential of developed vacuum-distillation technology and equipment, allowing to receiving the selenium containing more than 99.5 % of the main component within one step by cheap reagentless method, is shown in this article an example of several form of material