Abstract:
This invention relates to a single-step pyrometallurgical process for the recovery of non-ferrous metals from zinc bearing residues, in particular from by-products of the zinc and lead industry such as goethite and jarosite. A process for the recovery of metals from industrial Zn residues containing Zn, Fe and S is defined, wherein Zn is fumed, Fe is slagged, and S is oxidized to SO 2 , characterized in that the Zn fuming, the Fe slagging, and the S oxidation are performed in a single step process, by smelting the residues in a furnace comprising at least one submerged plasma torch generating an oxidizing gas mixture, and by feeding a solid reducing agent to the melt. The process achieves the oxidation of S and the slagging of Fe, while simultaneously achieving the reduction and the fuming of metals such as Zn.
Abstract:
Изобретение относится к цветной металлургии, в частности к способам переработки свинецсодержащих материалов. Задачей изобретения является повышение извлечения свинца в черновой металл и удельной производительности процесса при одновременном снижении удельных затрат энергоносителей. Способ включает приготовление и сушку шихты, обжиг-плавку шихты во взвешенном состоянии в атмосфере кислорода с получением оксидного расплава и смеси пылей с газами обжига-плавки, восстановление расплава при его фильтрации через слой разогретых частиц углеродистого восстановителя с получением металлического свинца, цинксодержащего оксидного расплава и газов. Шихту подвергают измельчению и классификации, а на стадию обжига-плавки подают выделенную фракцию сухой шихты, не менее 90% массы которой составляют частицы с размерами 0,01 -0,10 мм. При этом содержание свободной влаги в шихте на стадии ее приготовления составляет 8-16%, а в качестве дробленого углеродистого восстановителя используют уголь с содержанием в сухой массе общего углерода от около 49 до около 80% и летучих от около 11 до около 27%.
Abstract:
A method of processing flue dust that contains one or more compounds from a first group of zinc, lead and cadmium compounds, and contains iron compounds, involves heating the flue dust to cause a substantial portion of one or more of the compounds of the first group to become gas-borne. A carbonaceous material is introduced to the remaining flue dust, and the flue dust/carbonaceous material mixture is heated to cause a substantial portion of the remaining compounds from the first group to become gas-borne while retaining a substantial portion of the iron in a non-gas-borne condition. The gas-borne compounds are separated from the non-gas-borne compounds.
Abstract:
An improved method for the recovery of metal and/or chemical values from an industrial waste stream containing zinc, cadmium, lead and/or iron compounds by heating the waste stream in a reducing atmosphere, treating the resultant fumes in an ammonium chloride solution, separating any undissolved components from the solution, adjusting the pH of the solution, if necessary, to less than about 6.3, displacing undesired metal ions from the solution using zinc metal, treating the solution to remove therefrom zinc compounds, adjusting the pH of the solution to about 6.5 to about 7.0, and further treating the zinc compounds and the undissolved components, as necessary, resulting in the zinc products and the optional iron-carbon feedstock.
Abstract:
A method for the recovery of chemical values, such as metals including zinc, zinc oxide, iron-carbon feedstocks, lead and cadmium, from industrial waste streams which entails treating the waste streams with carbon and an ammonium chloride solution, separating any undissolved components from the solution, displacing metal ions including lead and cadmium from the solution using zinc metal, further treating the solution to remove zinc compounds therefrom, further treating the zinc compounds and the undissolved components with a dissolving solution, and further treating the displaced metal ions to recover lead, cadmium and zinc therein using various methods including electrolysis.
Abstract:
A process for recovering a metal chloride or mixed metal chloride from a solid waste material comprising recoverable metal containing constituents produced by lead, copper or zinc smelting and refining processes, said process comprising the steps of: (i) heating the solid waste material; (ii) treating the heated material of step (i) with a gaseous chloride to form a gaseous metal chloride containing product;and (iii) treating the gaseous metal chloride containing product of step (ii) to recover the metal chloride or mixed metal chloride. The metal chloride may be further treated to extract the metal itself.
Abstract:
A method for recovery of metals or metal compounds from metal-bearing solid particles comprising volatile compounds comprises supplying the solid particles (50) through a flame (25) of a burner (20). The volatile compounds are then evaporated by means of heat from the flame (25) while maintaining the original shape and state of aggregate of the solid particles, thereby providing a raw material product (34). The raw material product (34) is then recovered. By feeding the solid particles directly to the flame, a compact and efficient plant is provided. The melting process can be controlled in a satisfying way, avoiding melting of the metal-bearing solid particles supplied through the burner. The use of a burner is also described.
Abstract:
The invention relates to a process for the separation and recovery of non-ferrous metals from zinc-bearing residues, in particular from residues produced by the zinc manufacturing industry. The process comprises the steps of: - subjecting the residue to a flash or agitated bath fuming step, thereby producing an Fe bearing slag and Zn- and Pb-bearing fumes; and - extracting the Zn- and Pb-bearing fumes and valorising Zn and Pb; characterised in that CaO, SiO 2 and MgO are added as a flux before or during the fuming step so as to obtain a final slag composition with: formula (I) all concentrations being expressed in wt%. The invention also relates to a single-chamber reactor for Zn-fuming equipped with one or more submerged plasma torches as heat and gas sources.
Abstract:
The invention relates to a process for the separation and recovery of non-ferrous metals from zinc-bearing residues, in particular from residues produced by the zinc manufacturing industry. The process allows for the valorisation of metal values in a Zn-, Fe- and Pb-bearing residue, and comprises the steps of: -subjecting the residue to a direct reduction step, thereby producing a metallic Fe-bearing phase and Zn- and Pb-bearing first fumes; - extracting the Zn- and Pb-bearing first fumes and valorising Zn and Pb; - subjecting the metallic Fe-bearing phase to an oxidising smelting step, thereby producing an Fe-bearing slag and second metals-bearing fumes; - extracting the second metals-bearing fumes and valorising at least part of their metallic content. The main advantage of this process is that an environmentally acceptable output for Fe is obtained.
Abstract:
The invention relates to a process for obtaining zinc and other precious metals from raw materials containing chlorine or fluorine. According to said process raw materials are lyed with sulfuric acid without calcination and metals are separated electrolytically from the purified metallic salt solution. This novel process is economical because it removes chlorines and fluorines by feeding milling oxides to an alkaline lye stage with soda at 120 DEG C and making the halogenides soluble in water, the dissolved halogenides are washed out with water from milling oxides, milling oxydes with a low content of halogenides are lyed in sulfuric acid or cellular acid, and metals are separated from the obtained solution by electrolysis after purification.