Thesis (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The objective of this work was to achieve a completely automated fire assay system for the analysis of process control samples on a flotation plant in less than 120 minutes. With this in mind, a systems engineering approach was undertaken. The physical and chemical characteristics of the technology for each subsystem were investigated in turn and the critical factors that influenced accuracy, precision and analysis time were identified and optimised. Some of the key developments achieved during this work were: · Existing technology for the sampling, filtering, drying and grinding of flotation plant samples were evaluated and where necessary, modified for this application. · The fusion system was totally re-designed with a bottom-loading configuration called FIFA (Fast In-line Fire Assay) to make automation with a central robot possible. With the fast fusing flux developed, a quantitative collection of the platinum group elements with a fifteen-minute fusion was achieved compared to an hour for the classical method. · A robust automated separator system was developed to isolate the lead collector from the fusion in the molten state thereby separating it quantitatively from the slag. This allowed the automation of the entire fire assay process. · Methods to prepare lead standards for calibration were developed. These were used to optimise analytical protocols for the analysis of platinum group elements in lead using a spark optical emission spectrometer. This made it possible to accurately determine the quantities of platinum group elements in lead samples prepared by the automated fire assay system. · A fully automated system was developed that could meet the accuracy and precision requirements for the analysis of tailings and feed grade samples in concentrator slurry streams in less than one hour compared with the 24-72 hours required when using classical methods. The new fire assay technology including flux, FIFA system, oxygen lance and separator were all patented along with the automation vendor. This technology has made the first fully automated fire assay system a reality. / AFRIKAANSE OPSOMMING: Die hoofoogmerk van die studie was om ‘n totale geoutomatiseerde vuuressaieering stelsel te ontwerp vir die ontleding van prosesbeheermonsters van ‘n flotasieaanleg in ‘n bestek van 120 minute. Gedurende die ontwerp is ‘n ingeneursstelselbenadering gebruik. Die fisiese en chemiese kenmerke van elke deel van die tegnologie is eers afsonderlik en dan as ‘n geheel ondersoek. Die bepalende faktore wat akkuraatheid, presisie en ontledingstyd beinvloed het was geidentifiseer en geoptimeer. Die hoofpunte van die werk behels onder andere die volgende: · Bestaande tegnologie vir monsterneming, filtrasie, droging en vermaling van flotasiemonsters was ondersoek en is, waar nodig, aangepas vir die finale stelsel. · Die smeltingsisteem was in geheel herontwerp om monsters van onder in die FIFA (Fast In-line Fire Assay) sisteem te laai en sodoende die outomatisering met ‘n sentrale robot te vergemaklik. ‘n Vinnig smeltende vloeimiddel was ontwikkel wat ‘n kwantitatiewe versameling van die platinum groep elemente binne ‘n tydsduur van vyftien minute moontlik gemaak het, in vergelyke met die oorspronklike duur van die klassieke smelt metode van een uur. · ‘n Outomatiese skeier was ontwikkel waarmee die gesmelte loodversamelaar geskei kon word van die slakfase. Met die nuwe stelsel kon die hele vuuressaieerproses outomaties verloop. · Metodes is ontwikkel om loodstandaarde vir kalibrasie doeleindes te berei. Die standaarde is op hulle beurt weer gebruik om ‘n ontleding protokol daar te stel vir die analiese van die platinum groep elemente in lood, met behulp van ‘n vonkontlading-optiese-uitstraling-spektrometriese instrument. Ten einde was dit moontlik om outomaties klein hoeveelhede van die platinum groep elemente in monsters akkuraat te bepaal, na voorbereiding met behulp van die geoutomatiseerde vuuressaieering stelsel. · Die volle geoutimatiseerde stelsel was ontwikkel wat aan die akkurate en noukeurige vereistes voldoen het vir die ontleding van flotasie-uitskot-envoergraad monsters van die konsentraataanleg binne die bestek van ‘n uur. Die nuwe vuuressaieer tegnologie, insluitend die vinnig smeltende vloeimiddel, FIFA en skeier stelsels, asook die suurstof lanset is gepatenteer met die vervaardiger. Die studie het gelei tot die eerste volle geoutomatiseerde vuuressaieering stelsel wat tans gebruik word in die industrie.

No description available.

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1904. / The entire thesis text is included in file. Typescript. Illustrated by authors. Title from title screen of thesis/dissertation PDF file (viewed December 28, 2009)

M.Sc. (Geology) / Refer to full text for abstract

Bibliography: leaves 233-260. / xxi, 260, [30] leaves : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Uses the late-orogenic, structurally-controlled Junction gold deposit near Kambalda, Western Australia, to examine the potential of soil-gas geochemistry as an exploration vector in an environment where mineralisation is present, but no ore-related trace elements are detectable in the near-surface regolith. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology and Geophysics 1999

L’analyse qualitative et quantitative des minerais est une composante essentielle de l’entreprise minière. Elle permet à la fois d’anticiper et de contrôler la production, et ce à différents moments de la chaîne opératoire d’extraction et de transformation du minerai en métal : prospections, transactions, préparation des opérations de fonte. L’essai des minerais s’offre donc à une étude des techniques, et à celle de la structure des entreprises minières et de leurs stratégies d’exploitation. Cette thèse se consacre ainsi à la compréhension d’un savoir-faire, de son évolution et de son utilité économique. D’abord cantonné à un objectif de prospection, l’essai est opéré à moyenne ou grande échelle, selon un mode opératoire similaire aux opérations de production, et souvent pratiqué par des artisans de la métallurgie de transformation. La technique se rationalise au cours des deux derniers siècles du Moyen Âge en Europe centrale et dans les mines de la couronne d’Aragon. Elle aboutit à un travail de laboratoire dont la justesse et la rapidité font de l’essayeur l’un des pivots de l’entreprise minière moderne. Si la rareté des données médiévales a imposé une large diversité des fonds et des sites étudiés, la technique à petite échelle a fait l’objet d’une codification exhaustive au cours du XVIe siècle. Son étude se base sur des données textuelles et matérielles issues en grande partie de la province minière germanique, ainsi que sur une approche expérimentale. Elle donne lieu à un premier référentiel historique et archéologique en matière d’équipement d’essai (four à moufle et scorificatoire). / The qualitative and quantitative analysis of ores is a major component of mining exploitation. It allows metal production to be both anticipated and controlled at all stages of the chaîne opératoire, from the extraction of the ore to its transformation into metal: prospection, transactions and preparations for smelting. Therefore ore assaying may be used to study a wide range of aspects such as technical methods, mining society structure and exploitation strategies. This thesis seeks to understand the development and economic impact of a specific form of expertise. Assaying, which was initially linked only to prospection, was performed at medium or large scale, with a method similar to that used in the production process, and was often the work of craftsmen specialised in the manufacture of metal objects. The technique was improved and rationalised during the last two centuries of the Middle Ages in Central Europe and in the Crown of Aragon mines. The final result of this development was laboratory work where accuracy and promptness make the assayer one of the keystones of modern mining exploitation. A wide-ranging investigation of many archive collections and sites was necessary because of the scarcity of medieval data. The small-scale technique used during the 16th century, in contrast, has been the object of a thorough codification. The study of this laboratory process and its economic and social implications is based on textual and material data, mainly originating from the German mining area, but also from an experimental approach, thus producing a preliminary historical and archaeological reference work concerning assay facilities (muffle furnaces and scorifiers).

Made available in DSpace on 2016-04-28T14:16:16Z (GMT). No. of bitstreams: 1 Andrea Bortolotto.pdf: 923414 bytes, checksum: b7aa6819938401f2b747e43d546e5665 (MD5) Previous issue date: 2012-10-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / On the one hand, this dissertation examines to what extent the Chemical knowledge and the knowledge that sprang from experiments conducted in mines contributed to a new proposal of identification and classification of minerals in the 18th century, a period in which the demand for metals expanded. On the other hand, it is an attempt to discuss the sources that were used in order to propose a new concept, which is neither a result of a simple aggregation of previous concepts nor their neglect. As a matter of fact, the new concept goes beyond that, as it entails previous knowledge by complementing and transforming it. To do so, we analyzed in what terms Johann Andreas Cramer (1710 1777) moved closer and further from the various concepts available in his time to put forth a new method of mineral assaying based on the chemical behavior of the bodies, which allowed him to identify, extract and classify minerals more precisely. Among these sources, two stand out: Georg Ernst Stahl and Herman Boerhaave, rather different sources, considered even paradoxical by many historians. Such analysis has revealed that in the History of Chemistry there were moments in which lines of thought moved away. Nonetheless, there were also moments in which they blended. That finding leads us to conclude that the History of Chemistry is to be evaluated in terms of non-continuous analysis without disregarding continuity, though / Nesta tese, buscamos verificar, por um lado, em que medida os conhecimentos químicos e os conhecimentos advindos dos trabalhos realizados junto às minas contribuíram para uma nova proposta de identificação e classificação mineral no século XVIII, época em que a demanda por metais era crescente. E por outro, discutir as fontes usadas para propor um novo conhecimento, que não se constitui apenas por simples adição de conhecimentos anteriores nem por seu completo abandono. Mais do que isso, o novo conhecimento traz em sua elaboração conhecimentos anteriores que além de se completarem, se transformam. Para tanto, analisamos em que medida Johann Andreas Cramer (1710 - 1777) se aproximou e se distanciou dos diversos conhecimentos disponíveis em sua época para propor um método de análise mineral baseado no comportamento químico dos corpos, o que permitiu identificar, extrair e classificar os minerais com mais precisão. Dentre essas fontes destacam-se duas, Georg Ernst Stahl (1659-1734) e Herman Boerhaave (1668-1738), fontes bem diferentes e consideradas opostas por muitos historiadores. Essa análise nos revelou que, na História da Química, houve momentos em que as correntes de pensamento se distanciavam, mas também momentos em que se completavam. Tal constatação nos conduz à conclusão de que a História da Química deve ser pensada em termos de análises não-continuístas, não desprezando, entretanto, suas continuidades

The Kansanshi Cu-Au deposit located in the Domes region of the North West province of Zambia is characterised by structurally controlled high angle veins and associated alteration halos. The northwest trending Kansanshi antiform flanks the Solwezi syncline to the north and hosts the Kansanshi deposit and consists of tillites and metasedimentary rocks. Mineralisation is associated with Neoproterozoic Pan African deformation events experienced during the formation of the Lufilian fold belt; however recent findings confirm that structures in the form of reverse and normal faults and drag folds are critical controls on mineralisation within the deposit, Main pit in particular. Low angle faults occurring below the current pit are believed to have served as major fluid pathways during mineralisation. Age dating data from the Kansanshi deposit suggest that mineralisation took place between 512 and 503 Ma indicating that the event was associated with metamorphism. Two types of alteration are dominant within the Main pit (Kansanshi deposit) with the type and intensity of alteration being largely controlled by lithological units. Albite alteration occurs dominantly in phyllites and schists whereas dolomitisation is prevalent in calcareous units. Alteration is associated with mineralisation, and therefore is used as a condition for predicting vein or disseminated mineralisation. The high Au tenor at Kansanshi can be attributed to gold grains occurring in association with melonite (NiTe₂) and microfractured pyrite intergrown with chalcopyrite in sulphide and quartz dominated veins and veinlets. Analysis of gold grade distribution within the Main pit shows a clear concentration of the element along the major north-south trending structures like the 4800 and 5400 zones, possibly through supergene enrichment in the oxide-transition-sulphide zones. It is imperative that exploration for Kansanshi-type deposits will require geochemical and geophysical studies, understanding of the geology of an area to identify the three lithostratigraphic units (red beds, evaporites and reducing strata).

Made available in DSpace on 2016-04-28T14:16:32Z (GMT). No. of bitstreams: 1 Andrea Bortolotto.pdf: 93137 bytes, checksum: 6387d58e0c4ab8f964e1c7faa1071200 (MD5) Previous issue date: 2008-05-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this dissertation, we seek to corroborate which are the contributions of Chemistry to the identification, extraction and classification of minerals in the XVIII century, as well as, to discuss that the History of Chemistry must not be understood in terms of a tight line of thoughts. For that, we analyze the work of Johann Andreas Cramer (1710- 1777), Elements of the Art of Assaying Metals. Cramer proposed a method of mineral assaying based on the chemical behavior of the bodies, which allowed him to identify, extract and classify the minerals with more assertiveness. To elaborate his work, Crammer exploited the works of G. E. Stahl and of H. Boerhaave, two very different sources and considered, for a long time, opposite ideas. This fact has enlightened us that in the History of Chemistry there were moments in which the line of thoughts distanced themselves but also moments they completed each other, evidence that lead us to the conclusion that the History of Chemistry must be faced in terms of non-progressive analysis, not despising, however, its continuity / Nessa dissertação, buscamos verificar quais as contribuições da Química para a identificação, extração e classificação mineral no século XVIII, bem como discutir que a História da Química não deve ser entendida em termos de correntes estanques de pensamento. Para tanto, analisamos o trabalho de Johann Andreas Cramer (1710-1777), Elements of the Art of Assaying Metals. Cramer propôs um método de ensaio mineral baseado no comportamento químico dos corpos, o que permitiu identificar, extrair e classificar os minerais com mais precisão. Para elaborar seu trabalho, Cramer utilizou-se dos trabalhos de G. E. Stahl e de H. Boerhaave, fontes bem diferentes e consideradas opostas por muito tempo. Esse fato nos revelou que na História da Química houve momentos em que as correntes de pensamento se distanciavam mas também momentos em que se completavam, constatação esta que nos conduz à conclusão de que a História da Química deva ser pensada em termos de análises não-continuístas, não desprezando, entretanto, suas continuidades