Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1922. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed June 4, 2009) Includes bibliographical references.

Thesis (M.Eng.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 163-174.

Thesis (Ph.D.) - University of Queensland, 2006. / Includes bibliography.

Ethnoarchaeological research of indigenous iron-working in Africa and, more recently, in parts of Asia, has attempted to interpret past technology through the lives and memories of blacksmiths and smelters. In India, recent archaeological and historical research of iron-working and other forms of craft production has examined the social position of specialized craft producers within regional caste-structures. This thesis incorporates both these approaches to study traditional iron-working communities in northern Telangana, a region in south-central India. Anthropological theories of craft production and power are employed to provide a nuanced interpretation of the archaeometallurgical and ethnographic data from the study area. Medieval travelogues and colonial documents attest the presence of a thriving preindustrial iron and crucible steel-manufacturing tradition in northern Telangana. Initial archaeological and historical investigations in the region by Lowe (1989) and Jaikishan (2009) identified a significant number of sites related to early iron and crucible steel production. The Pioneering Metallurgy project of 2010 (Juleff et al., 2011) surveyed within the four districts of northern Telangana to investigate the origin and development of these technologies. Besides locating and recording archaeometallurgical evidence, the project also conducted ethno-metallurgical enquiries to record the members of rural blacksmith communities at work. This highlighted the potential for an in-depth ethnoarchaeological study to understand the socio-cultural context of these indigenous technologies by unraveling the lives of the descendants of iron-smelters and steelmakers of northern Telangana. This was the starting point of the present research project. My research investigates a dynamic set of relationships between craft, people and space—physical and social. The ethnographic data for this research is collected through 63 formal and numerous informal interactions with the iron-workers of the region. These interactions and other collected data are presented in appendices. The lives of five practitioners with different specialized skills provide the entry point into this research which is presented in two-parts. After setting the background, Part A investigates the intricate relationship between indigenous smelting technologies, smelters and place. Based on interactions with older members of the Mudda Kammari (smelter) community, this study attempts to reconstruct the practices of iron-smelting from their individual and collective memory. Where possible, elderly smelters led me to the rivulets where ore was mined and showed the surviving pits for preparing charcoal, while explaining technological details. The spatial locations of these were recorded and analyzed in relation to the smelting sites and present habitations of the Mudda Kammari (smelter) communities. Apart from technological detail, their memory also provided insight into the social and economic networks in which indigenous iron-smelting operated. The demise of indigenous iron-smelting in the first half of 20th century compelled the Mudda Kammari to adopt blacksmithing on a full-time basis. As a result they lost their distinct smelter-identity. A host of specialist iron-working groups like the scissors-smiths, sword-smiths and firearm makers in the area also lost their specialized skills and distinct identities faced with competition from industrial products and government prohibition onthe domestic weapon manufacturing industries from the 1950s. All of these groups were obliged to take up manufacturing agricultural products, and therefore, became homogenized as Kammari (blacksmiths). Lopsided agrarian development, marketization of harvests and recent mechanization of agriculture have ruptured the traditional relations of exchange between the Kammari and the agrarian community. This has significantly reduced the demand for their services, and resulted in displacement of their craft and lives. Consequently, the identity and position that the Kammari enjoyed in rural social space and reinforced through cult performance has degenerated. This led to a further homogenization of artisan identities, supported by a new eclectic identity narrative, which replaced the older, individual craft-community focused identities. Part B of this research deals with this homogenization process in detail. It interrogates the relationship between the decline in craft and the evolution of artisan identity. Based on ethnographic fieldwork and archival studies, this section examines how identities of ironworking communities in northern Telangana are reconstituted and articulated over time with the enfeeblement of their craft. In the final section of the thesis I bring the diverse data together to form a nuanced understanding of the social, cultural and economic context of iron working in northern Telangana. Based on the complexity of iron-worker identity in northern Telangana, this section cautions against drawing straightforward ethnographic analogies to study the archaeological record. I conclude by proposing how this research can benefit future ethnoarchaeological research of craft production and in studying traditional craft and craftsmen in a growing market economy.

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Thesis (MScEng (Process Engineering))--Stellenbosch University, 2008. / The electric smelting furnace is found at the heart of the platinum recovery process where the power input from the electrodes produces a complex interplay between heat transfer and fluid flow. A fundamental knowledge of the dynamic system hosted by the electric furnace is valuable for maintaining stable and optimum operation. However, describing the character of the system hosted by the electric furnace poses great difficulty due to its aggressive environment. A full-scale threedimensional Computational Fluid Dynamics (CFD) model was therefore developed for the circular, three-electrode Lonmin smelting furnace. The model was solved as time dependent to incorporate the effect of the three-phase AC current, which was supplied by means of volume sources representing the electrodes. The slag and matte layers were both modelled as fluid continuums in contact with each other through a dynamic interface made possible by the Volume of Fluid (VOF) multi-phase model. CO-gas bubbles forming at electrode surfaces and interacting with the surrounding fluid slag were modelled through the Discrete Phase Model (DPM). To account for the effect of concentrate melting, distinctive smelting zones were identified within the concentrate as assigned a portion of the melting heat based on the assumption of a radially decreasing smelting rate from the centre of the furnace. The tapping of slag and matte was neglected in the current modelling approach but compensation was made for the heating-up of descending material by means of an energy sink based on enthalpy differences. Model cases with and without CO-gas bubbles were investigated as well as the incorporation of a third phase between the slag and matte for representing the ‘mushy’ chromite/highly viscous slag commonly found in this region. These models were allowed to iterate until steady state conditions has been achieved, which for most of the cases involved several weeks of simulation time. The results that were obtained provided good insight into the electrical, heat and flow behaviour present within the molten bath. The current density profiles showed a large portion of the current to flow via the matte layer between the electrodes. Distributions for the electric potential and Joule heat within the melt was also developed and showed the highest power to be generated within the immediate vicinity of the electrodes and 98% of the resistive heat to be generated within the slag. Heat was found to be uniformly distributed due the slag layer being well mixed. The CO-gas bubbles was shown to be an important contributor to flow within the slag, resulting in a order of magnitude difference in average flow magnitude compared to the case where only natural buoyancy is at play. The highest flow activity was observed halfway between electrodes where the flow streams from the electrodes meet. Consequently, the highest temperatures are also observed in these regions. The temperature distribution within the matte and concentrate layers can be characterized as stratified. Low flow regions were identified within the matte and bottom slag layer which is where chromite and magnitite deposits are prone to accumulate. The model results were partially validated through good agreement to published results where actual measurements were done while also falling within the typical operating range for the actual furnace. The modelling of the electric furnace has been valuably furthered, however for complete confidence in the model results, further validation is strongly recommended.

Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2006. / An understanding of the behaviour of chromium in mattes equilibrated with chrome-saturated slags is essential for the prediction and control of chromium deportment in these melts. The main ore reserves of South Africa’s platinum group metals (PGM) are associated with the Merensky and UG2 reefs of the Bushveld Complex. The gradual depletion of the pyroxenitic Merensky reef over the years has necessitated the PGM industry to exploit the underlying chromiterich UG2 reef. The problem with UG2 reef is that it contains significant amounts of chromium, this being typically 5% (reported as Cr2O3) against <1% for the Merensky reef (in concentrates). Chromium has a number of deleterious effects on base-metal smelting processes. Under given conditions, it forms chromite spinels, which can accumulate and, over a period of time, form undesirable build-ups resulting in reduced furnace operational volume. The chromite spinels also tend to increase slag viscosity, thereby impacting negatively on the slag/matte separation, which leads to matte entrainment in slag. Moreover, high viscosities lead to problems with tapping of the furnace melts. Finally it can be said that chromium that deports to the matte during smelting will normally tend to precipitate as spinels during subsequent converting, and lead to the formation of very stable and unwanted slag foams in the converter. In literature, there exists very little published work on the behaviour of chromium in sulphur-saturated systems such as matte-smelting furnaces. The few publications that exist in this area do not cover the effect of controlling all the pertinent variables simultaneously on the behaviour of chromium in mattes in equilibrium with chromium-containing slags. Hence the main focus of the oxygen fugacities on the mineralogical and deportment behaviour of chromium in a matte-slag system. All the three variables (temperature, oxygen fugacity (pO2), and sulphur fugacity (pS2)) were investigated at three levels. Temperatures studied were 1300°C, 1400°C, and 1500°C. Oxygen and sulphur fugacities were established by controlling the mix-ratios of purified carbon dioxide, carbon monoxide, sulphur dioxide, and argon. Oxygen fugacities were maintained at 10-10atm, 10-8atm, and 10-6atm; whereas sulphur fugacities were maintained at 10-6atm, 10-4atm, and 10- 2atm. In order to investigate the effect of each of these three variables (temperature, pS2, and pO2) at different levels of the other variables, a completely randomised 33 full factorial experimental design was adopted. The study revealed that chromium is generally present in matte as both dissolved CrS and as precipitated oxidic and sulphidic chromium spinel phases. It was shown that as the conditions become more oxidising (pO2 = 10-6atm), CrS (which is soluble in matte) becomes a predominant phase, and as the conditions become more reducing (pO2 = 10-10atm), the sulphospinel, daubreelite (FeCr2S4), becomes a more predominant phase. Oxidic chromium spinels were found to be present in matte under the more oxidising conditions (pO2 of 10-6atm) of this investigation. The presence of the above-mentioned phases was confirmed using X-ray diffraction. Subject to the experimental conditions employed in this research, chromium was found to partition the least to matte under the conditions of; low temperature, high pO2, and low pS2. Conversely, chromium was found to partition the most to matte under the conditions of; high temperature, low pO2, and high pS2.

After carbon, phosphorus is the most commonly detected element in archaeological iron. The typical phosphoric iron range is 0.1wt% to 1wt%P. The predominant source of phosphorus in iron is the ore smelted. Around 60% of economic UK rock iron ore formations contain over 0.2%P. Under fully reducing conditions, both in liquid-state (cast iron) and solid-state bloomery smelting (direct reduction) processes, such rock ores would be predicted to produce phosphoric iron, and bog iron ores even more so. Ore-metal-slag phosphorus ratios for bloomery iron are derived here, by means of: laboratory experiments; full-scale experimental bloomery smelting; and analysis of remains from three Medieval and two Late Roman-Iron Age iron production sites in England and the Netherlands. Archaeological ore, slag, metal residues (gromps), and iron artefacts were analysed by metallography, SEM-EDS, EPMA, and XRD. The effects of forging and carburising on phosphoric iron were studied by experiment and artefact analysis. The ore to slag %P ratio for solid-state reduction was determined to range from 1:1.2 to 1: 1.8. The ore to metal %P ratio varied from 1:0.2 to 1:0.7-1.4, depending on furnace operating conditions. Archaeological phosphoric iron and steel microstructures resulting from non-equilibrium reduction, heat treatment, and mechanical processing are presented to define the technology of early phosphoric iron. Microstructures were identified by a combination of metallography and chemical analysis. The phosphoric iron artefacts examined appear to be fully functional objects, some cold-worked and carburised. Modern concepts of 'quality' and workability are shown to be inapplicable to the archaeological material.

The beginnings of metallurgical activity have intrigued scholars for decades. In this dissertation, I explore early metallurgical activity on the Iranian Plateau represented by the evidence at Tal-i Iblis in southern Iran, and Seh Gabi and Godin Tepe in central northern Iran. Together, these sites offer a diachronic view of metal production on the Plateau as well as a view of metallurgical activities practiced at different scales of production. The metallurgical materials from Tal-i Iblis are firmly dated to the late 6th to early 5th millennia BCE, and this corpus includes hundreds of crucible fragments excavated from multiple trash dumps. Seh Gabi and Godin Tepe offer a smaller range of production materials from the 4th through 2nd millennia BCE, but they also include a large collection of finished metal objects. These later materials differ in style and process from the Iblis debris.Thorough examination of these artifacts, combined with comparison to a series of carefully controlled casting experiments, has returned numerous significant results. The metallurgy of the Iranian Plateau does not fit the standard model of early metallurgical development. The Iblis crucibles do not reflect an early "experimental" stage in copper production. Rather, these artifacts represent a carefully controlled, production process with a narrow range of variability in both temperature and reducing atmosphere. Further, there is clear evidence for the preference of arsenical-copper alloys at Tal-i Iblis. These ancient craftspeople sought high-quality ores from a source (the Talmessi copper deposit) over 500 km from their production facility.Metallurgical production on the Iranian Plateau is also characterized by the long-term use of crucibles as the primary reaction vessel well into the 2nd millennium BCE. There are some production centers on the Iranian Plateau that see the use of furnaces during the 3rd millennium, but crucible use persists at many sites. At Godin Tepe--a site with significant evidence for contact with the Mesopotamian lowlands--variability in crucible form increases in later periods to include an Egyptian-style crucible during the 2nd millennium BCE. The presence of this crucible suggests that there was contact with foreign metallurgical processes, but the preference for small, portable reaction vessels persisted.

Copper losses to slag are generally between 0.7-2.3% during the copper matte smelting stage. In this study, the aim was to reduce these losses in the slag phase. For this purpose, usage of some additives (especially calcined colemanite labeled as CC, boric oxide-B2O3 and calcium oxide-CaO as well) as flux material was investigated. The flash furnace matte-slag (FFM-FFS) obtained from Eti Copper Inc. and a master matte-slag (MM-MS) produced synthetically were used as starting materials. Additives were tested in various amounts under two different atmospheres (N2 and low Po2 obtained by mixture of CO2/CO gases). Temperature and duration were also used as experimental variables. Experimental results have indicated that 2 hours was sufficient to obtain a low copper content in slag about 0.3% and 0.4% for FFS and MS, respectively. It was also seen that the copper content in slag decreased with increasing CC addition at all oxygen partial pressures and at all temperatures. Furthermore, the addition of all additives up to 4% had great influence in lowering the copper content in the final slags (~0.3%Cu). From FactSage calculations, it could be concluded that the colemanite addition decreased the liquidus temperature which led to early melting of slag and allowed enough duration for settling of matte particles within the slag without substantial changing its viscosity, which resulted in less mechanical copper losses to the slag. By using colemanite in copper production, it was possible that a new application area for boron compounds which are produced in Turkey could be created.