Thesis--University of Missouri, School of Mines and Metallurgy, 1908. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed November 18, 2008)

The copper smelting industry has under gone extreme change over the past three decades. These changes have reordered dramatically the demand for inputs and the way in which those inputs have been utilized. The stimulus for change has come from multiple sources, and chief among these stimuli has been the mandate to sharply curtail the atmospheric release of sulfur dioxide. Even though the total emissions were lower than those from steam generation of electricity and from the refinery and petro-chemical industry, the perceived local and regional impact of sulfur dioxide forced extreme changes in the utilization of fundamental inputs of capital, labor, energy and materials.This study attempts to analyze these input use changes by modeling the industry as a translog cost function and by generating a number of associated elasticities. In addition to the four basic inputs, the model includes as control variables output, and other variables that represent pollution abatement and technical change.The challenge of estimating a large model on a limited number of observations has delivered information that is more limited in scope than was originally desired. The proxy for technical change did not produce significant parameters and the pollution abatement proxy is limited in its participation in the results. The range of elasticities computed reveal a picture of an industry characterized by inelasticity, in general, labor and energy being part of the exceptions. The industry is found to be sensitive to output level in its degree of elasticity among inputs.The translog model is found to be an effective tool for industry analysis. The promise of detailed analytical information may be even greater at the firm level where data are more accurate and the number of observations far greater.

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...

Employing a technological approach derived from the 'Anthropology of Technology' theoretical literature, this thesis concerns the identifi cation and explanation of change in prehistoric extractive metallurgical behaviour in the Khao Wong Prachan Valley of central Thailand. The 'Valley' metallurgical complex, amongst the largest in Eurasia, constitutes Southeast Asia's only documented industrial-scale copper-smelting evidence. The two smelting sites investigated, Non Pa Wai and Nil Kham Haeng, provide an interrupted but analytically useful sequence of metallurgical consumption and production evidence spanning c. 1450 BCE to c. 300 CE. The enormous quantity of industrial waste at these sites suggests they were probably major copper supply nodes within ancient Southeast Asian metal exchange networks. Excavated samples of mineral, technical ceramic, and slag from Non Pa Wai and Nil Kham Haeng were analysed in hand specimen, microstructurally by refl ected-light microscopy and scanning electron microscopy (SEM), and chemically by polarising energy dispersive x-ray fl uorescence spectrometry ([P]ED-XRF) and scanning electron microscopy with energy dispersive x-ray fl uorescence spectrometry (SEM-EDS). Resulting analytical data were used to generate detailed technological reconstructions of copper smelting behaviour at the two sites, which were refi ned by a programme of fi eld experimentation. Results indicate a long-term improvement in the technical profi ciency of Valley metalworkers, accompanied by an increase in the human effort of copper production. This shift in local 'metallurgical ethos' is interpreted as a response to rising regional demand for copper in late prehistory.

In the copper smelting processes, the viscosity of the matte and the slag is an important factor for establishing efficiency. Impurities in the concentrates affect the viscosity not only by changing the melt structure but also by promoting precipitation of solid phase which sharply rises it. In this master thesis, a comprehensive methodology was established to study the MgO effects on the properties of a copper smelting slag. Thus, glassy samples were obtained and after confirmation of the composition and the glassy structure with EDS, SEM, and XRD analysis, they were examined through Ramanspectroscopy to study their glassy structure. Moreover, Mössbauer spectroscopy was used to determine the amount of Fe3+ in the samples. Models from the literature were compared to the experimental data. Coherence with the literature was found with the effect of MgO as a network modifier of the oxide melt structure and a promoter of high coordinated structures. Estimations through models were performed to study the iron redox equilibria of the melt and were compared with experimental data, but it was not possible to find the limit of Fe3+ at which precipitation of solid phase initiates. / I kopparsmältningsprocesserna är mattans och slaggens viskositet en viktig faktor för att uppnå effektivitet. Föroreningar i koncentraten påverkar viskositeten inte bara genom att ändra smältstrukturen utan också genom att främja utfällning av fast fas som kraftigt höjer den. I denna magisteruppsats fastställdes en omfattande metod för att studera MgO-effekterna på egenskaperna hos en kopparsmältningsslagg. Således erhölls glasiga prover och efter bekräftelse av kompositionen och den glasiga strukturen med EDS-, SEM- och XRD-analys undersöktes de genom Ramanspektroskopi för att studera deras glasstruktur. Dessutom användes Mössbauerspektroskopi för att bestämma mängden Fe3+ i proverna. Modeller från litteraturen jämfördes med experimentella data. Överensstämmelse med litteraturen hittades med effekten av MgO som ett nätverksmodifierare av oxidsmältstrukturen och en promotor för högkoordinerade strukturer. Uppskattningar genom modeller utfördes för att studera smältans järnredoxjämvikter och dessa jämfördes med experimentella data, men det var inte möjligt att hitta gränsen för Fe3+ vid vilken utfällning av fast fas initierades.

The aim of this thesis is to reach further understanding of the development of environmental adaptation in Swedish heavy industry by studying the case of the Rönnskär Smelter 1960-2000. More specifically, the aim of the thesis is to investigate the interplay between firm level environmental adaptation and national environmental politics and economic development. To fulfil this aim, the following questions are asked: How have company activities such as production processes, organisation and company strategies been developed and adopted in order to meet environmental demands with maintained competitiveness? How have company activities been framed by environmental policies and the specific environmental regulations, relevant for this case? What other factors, beside environmental regulations, have driven and framed the environmental adaptation process of the firm? The study concludes that a long-range competitive environmental adaptation was reached by a combination of investments in environmental technology with an overall rationalisation and modernisation of the enterprise. The study suggests that the environmental adaptation process of the Rönnskär Smelter became part of an overall process of industrial modernisation during the period, which reflects a wider context than the environmental issue itself. It mirrors technological development on other fields than the environment, and an increasing competition on a global scale that called for lower unit costs of production. This led to a modernisation for pollution reduction strategy that enabled the firm to increase production but still cutting its pollution levels considerably over time. The result is partly consistent with the Porter hypothesis that suggests that strict environmental regulation can strengthen firms’ and nations’ competitiveness. Time series data shows that emissions from the Rönnskär factory have radically declined since the 1960s. For these changes, process technology has proven to be most important. Technological adjustments came about through a step-by-step adaptation. It is clear that internal solutions, developed by the companies’ own engineers were more important at an early stage, when the supply of external solutions was limited. The study also concludes that environmental regulation has strongly influenced the environmental adaptation at the Rönnskär Smelter. Of most importance is the Environmental Protection Act (EPA: Miljöskyddslagen) implemented in 1969. In the economic historian Nathan Rosenberg’s terminology, this study suggests that the EPA model of individual testing promoted long-term innovative and cost-effective technical solutions, because it was consistent with decentralised experimental activity and the specific conditions that characterise the dynamics of technological development. However, not much can be said before comparative studies within the Swedish system have been conducted, or perhaps most fruitful, between various national systems of environmental protection. This study also concludes that the environmental issue became of strategic dignity at the very beginning of the 1970s, mainly as a consequence of the implementation of the EPA. Even though environmental issues did not become important for market strategies until the 1990s, the environmental issue called already in the 1970s for adjustments that required financial and personnel resources that demanded priorities and strategic decisions at the highest level of the organisation. The study also concludes that even though the technological dimension has played the most decisive role for lowering emissions, the significance of organisation has increased over time. While the 1960s, and especially the 1970s, brought about substantial pollution reductions through new technology, organisational aspects became relatively more important when the costs of abatement were rising in the 1980s. Organisational co-ordination, division of local responsibilities and education of personnel became a supplement to technology to obtain further pollution reductions. The technician as the “environmental hero” of the firm was successively replaced by the organisational co-ordinator.

The present thesis gives a summary of results obtained through theoretical and experimental studies of systems with relevance to copper smelting and converting. Many chemical elements are involved in the copper production pro­cesses and a detailed experimental study would be very time- consuming and expensive. A complicating fact is also the corrosivity of the liquid phases towards container material. A powerful alternative is equilibrium calculations, in which models for the liquid phases as well as reliable basic thermodynamic data are needed. In the present thesis, a generalized structure based model for liquid silicates was developed and used in assessments of the sys­tems PbO-SiO2, Fe-O-SiO2, CuO0.5-SÌO2 and Cu-Fe-O-SiO2. In the model, the non-ideal silicate melt is treated as an ideal solu­tion but containing a few complexes. The PbO-Si02 melt could be described by introducing the complexes Pb3Si207, Pb4Si4010 and Pb13Si12O37 in addition to the components PbO and Pb2Si04. The species considered in the Fe-O-SiO2 melt were FeO, FeO1.5, Fe2Si04, Fe3Si207, Fe3Si6O15 and in the CUO0.5-SiO2 melt CuO0.5 ana CU4SiO4. Trie calculated phase diagrams, the activities of me­tal oxides and the oxygen partial pressures were all in good agreement with the published data. Two of the papers in this thesis concern the determination of Gibbs free energies for Cu2S(s,l) and Ca2Fe2O5(s) through emf measurements utilizing a solid electrolyte. Activities and termi­nal solubilities in the solid solution [Fet,Ca]0 were also deter­mined. The results obtained from the quantitative equilibrium calcula­tions for conventional copper smelting and converting were used to outline the overall reactions taking place and the outcome of changes in process parameters. Comparison with observed values, however, showed that the copper and magnetite contents in slag were calculated too low. These discrepancies could be completely explained by using a non-equilibrium approach in which the con­verter was assumed to consist of several segments with concentra­tion gradients between the segments. / digitalisering@umu.se