Die vorliegende Arbeit beinhaltet Modelluntersuchungen der Strömungsverhältnisse am Beispiel des Imperial Smelting-Ofens. Die Versuche verfolgen das Ziel, Erkenntnisse über optimale Einblasbedingungen der Sekundärluft zu erhalten, um die Neigung zur Ansatzbildung verringern zu können. Die durchgeführten Untersuchungen lassen die Schlussfolgerung zu, dass die Simulation der in der Gasphase ablaufenden Strömungsvorgänge eines pyrometallurgischen Aggregates mittels eines physikalischen Modells realisierbar ist. Aufgrund der Berücksichtigung der Arbeitsweise des Ofens sowie der Ähnlichkeitstheorie bei der Prozessmodellierung, können die erhaltenen Ergebnisse in der Tendenz auf das Original übertragen werden. Für die weitere Erklärung der Problematik der Ansatzbildung in der IS-Anlage werden thermodynamische Berechnungen durchgeführt, Ansatzproben aus dem Originalofen analysiert und die Abscheidungen der Nebelflüssigkeit an den Modellwänden untersucht. Im Ergebnis dieser Untersuchungen werden Vorschläge zur Optimierung des IS-Prozesses unterbreitet.

Artefacts relating to tin smelting from tin mills or 'blowing houses' in Devon and Cornwall, plus material from smelting sites that cover a range of dates from the Bronze Age through to the 19th Century, were examined: these include metallic tin, furnace linings, ore samples and slag. Analysis of tin slags from over forty sites was carried out, to determine microstructure and chemical composition. Techniques employed included optical and scanning electron microscopy, X-ray fluorescence and ICP mass spectrometry. Analysis indicates that slag appearance and composition are heavily influenced by local geology. Composition, particularly iron content, is shown to have a strong effect on slag melting point and viscosity, and the implications for the purity of metal produced are discussed. Bringing together the evidence provided by slag chemistry, documentary sources and smelting remains in the archaeological record, changes in tin smelting technology through time, and the consequences thereof, are considered.

No description available.

Thesis (M.A.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 5, 2007) 9 unnumbered blank pages at end of manuscript. Includes bibliographical references.

Thesis (M.Sc.(Applied Science-Metallurgy))--University of Pretoria, 2008. / Abstract in English. Includes bibliographical references (leaves 136-145).

Please read the abstract in the section 00front of this document Copyright 2000, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bessinger, D 2000, Cooling characteristics of high titania slags, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-07212006-102324 / > H 95 / Dissertation (MSc (Metallurgy))--University of Pretoria, 2007. / Materials Science and Metallurgical Engineering / unrestricted

Die vorliegende Arbeit beinhaltet Modelluntersuchungen der Strömungsverhältnisse am Beispiel des Imperial Smelting-Ofens. Die Versuche verfolgen das Ziel, Erkenntnisse über optimale Einblasbedingungen der Sekundärluft zu erhalten, um die Neigung zur Ansatzbildung verringern zu können. Die durchgeführten Untersuchungen lassen die Schlussfolgerung zu, dass die Simulation der in der Gasphase ablaufenden Strömungsvorgänge eines pyrometallurgischen Aggregates mittels eines physikalischen Modells realisierbar ist. Aufgrund der Berücksichtigung der Arbeitsweise des Ofens sowie der Ähnlichkeitstheorie bei der Prozessmodellierung, können die erhaltenen Ergebnisse in der Tendenz auf das Original übertragen werden. Für die weitere Erklärung der Problematik der Ansatzbildung in der IS-Anlage werden thermodynamische Berechnungen durchgeführt, Ansatzproben aus dem Originalofen analysiert und die Abscheidungen der Nebelflüssigkeit an den Modellwänden untersucht. Im Ergebnis dieser Untersuchungen werden Vorschläge zur Optimierung des IS-Prozesses unterbreitet.

Metallurgical activities are one of the important sources of environmental pollution, especially due to inappropriate treatment of waste materials containing potentially harmful elements. Soils in the vicinity of smelting operations are the main target reservoirs for these emitted contaminants. The aim of this study was to depict reactivity of copper smelter flue dusts and slags in aqueous and soil environments using laboratory and field experiments. Slags exhibited high concentrations of As (up to 0.95 wt.%), Cu (up to 2.4 wt.%), Pb (up to 1.02 wt.%), Sb (up to 0.37 wt.%), and Zn (up to 2.45 wt.%). Copper and other metal(loid)s were predominantly bound in sulphides, especially bornite, digenite, chalcocite, and galena. Flue dusts were mainly composed of As2O3 phase (arsenolite and claudetite), with minor amounts of gypsum, galena, quartz and covellite. The main contaminants in the dust were As (53.3 wt.%), Pb (3.41 wt.%), Sb (1.26 wt.%), Zn (1.41 wt.%), Cu (1.07 wt.%) and Bi (0.80 hm.%). The leaching tests performed in the pH range of 3-12 indicated that the release of metal(loid)s from both types of metallurgical wastes was highly pH-dependent. During the leaching in deionised water, up to 42 mg/kg As was released from slags and up to 52.6 g/kg was leached from the flue dust; the latter highly...

Silver and palladium can be found in the so called palladium-ceramics which comes from catalyst production. These valuable metals needs to be recovered from these wastes in order to further increase both the environmental and economic sustainability of our society. This material has also been suspected of causing some problems at Boliden’s smelter Rönnskär during the silver smelting. Unfortunately due to the nature of massive economics at work in precious metal production there has not been much published work around this subject. Therefore this works seeks to increase the understanding of how this waste affects the A-slag in the precious metal production at Rönnskär.   This work takes a look at how certain fluxes and temperatures affects the slag and metal phases, as well as how increasing the addition of the palladium-ceramic affects the melt. It does so by making screening tests with a basic setup of slag from the process, silver granules and additions of coke and sodium carbonate at different temperatures.   The results show that using a reducing environment by adding coke does increase the recovery of the precious metals. Increasing the temperature of the melt also shows an improvement in the recovery of the precious metals.  Furthermore the basis to an alternative way of using this material, consisting of smelting it together with silver and fluxing materials has been suggested in this work in order to eliminate the possible problems it causes in the current process. / Silver och palladium kan finnas i materialet som kallas katalysatormassa som kommer från framställningen av katalysatorer. Dessa värdefulla metaller måste återvinnas från detta avfall för att öka hållbarheten i vårt samhälle både miljömässigt och ekonomiskt. Materialet har också varit en möjlig orsak till problem vid silversmältningen på Bolidens smältverk, Rönnskär. Tyvärr på grund av den enorma ekonomin kring ädelmetaller och deras produktion har det inte publicerats många artiklar om detta ämne. Därför försöker detta arbete att öka förståelsen av hur detta avfall påverkar A-slaggen hos ädelmetallframställningen på Rönnskär.   Detta arbete undersöker på hur olika flussmedel och temperaturer påverkar slaggen och metallfasen, samt hur en ökad mängd katalysatormassa påverkar smältan. Det görs genom att göra flera testsmältor med en bas med slagg från processen, silvergranuler samt tillsatser av koks eller natriumkarbonat vid olika temperaturer.   Resultaten visar att användandet av en reducerande miljö genom tillsättningen av koks ökar återvinningen av ädelmetallerna. En ökad temperatur på smältan har också visat på en ökad återvinning. Utöver detta så har grunden till ett alternativt sätt att använda sig av materialet tagits fram. Detta alternativ består av att smälta materialet tillsammans med silver och flussmedel och har tagits fram för att undvika möjliga problem i befintlig process.

Artefacts relating to tin smelting from tin mills or ¿blowing houses¿ in Devon and Cornwall, plus material from smelting sites that cover a range of dates from the Bronze Age through to the 19th Century, were examined: these include metallic tin, furnace linings, ore samples and slag. Analysis of tin slags from over forty sites was carried out, to determine microstructure and chemical composition. Techniques employed included optical and scanning electron microscopy, X-ray fluorescence and ICP mass spectrometry. Analysis indicates that slag appearance and composition are heavily influenced by local geology. Composition, particularly iron content, is shown to have a strong effect on slag melting point and viscosity, and the implications for the purity of metal produced are discussed. Bringing together the evidence provided by slag chemistry, documentary sources and smelting remains in the archaeological record, changes in tin smelting technology through time, and the consequences thereof, are considered. / R. F. Tylecote Memorial Fund, administered by the Historical Metallurgy Society, and the Francis Raymond Hudson Memorial Fund.