Le Burkina Faso, comme d'autres pays africains, a connu une métallurgie primaire de fer il y a des millénaires. Dans l'état actuel des recherches, la plus ancienne date se situe autour du VIIIe siècle avant notre ère, dans le Bwamu, à Douroula, dans l'Ouest du Burkina Faso. Dans presque toutes les régions du pays, les vestiges relatifs à la production ancienne du fer sont visibles et constituent aujourd'hui, des témoins tangibles des savoirs et savoir-faire des anciens métallurgistes. La province du Bam, notre zone d'étude, est localisée dans la région du centre-nord du Burkina Faso et couvre une superficie de 3931 km2. Nos prospections archéologiques y ont permis de répertorier plus d'une centaine de vestiges et sites résultant directement de cette production sidérurgique. Les investigations ethno historiques, archéologiques et archéométriques de ces vestiges ont permis d'élucider les origines de la sidérurgie dans cette partie du Burkina Faso et de caractériser les traditions techniques qui furent utilisées par les anciens métallurgistes. Ainsi, cinq tradition techniques ont été identifiées et décrites (Bl , B2, B3, B4, BS). Elles se sont développées à de périodes différentes. En plus des aspects techniques, les implications socioculturelles et économiques engendrées par l'industrie locale du fer, ont été appréhendées afin de mieux cerner la place qu'occupaient le artisans du fer dans la société traditionnelle de la province du Bam. / Burkina Faso, like other African countries, experienced a primary iron metallurgy millennia ago. In the current researches, the earliest date is around the eighth century BC, in the Bwamu at Douroula, in western Burkina Faso. In almost all regions of the country, vestiges relating to the former iron production are visible and are now tangible witnesses of knowledge and the ability of ancient metallurgists. Bam province, our study area is located in the region of north-central Burkina Faso and covers an area of 3931 km2. Our archaeological surveys have enabled to identify more than a hundred sites and remains resulting directly from the steel production. Ethno historical, archaeological and archaeometric investigations of these remains have elucidated the origins of the steel industry in this part of Burkina Faso and permitted to characterize the technical traditions that were used by the ancient metallurgists. Thus, five technical traditions have been identified and described (B1, B2, B3, B4, B5). They have been developed at different times. Besides the technical aspects, socio-cultural and economic implications caused by the local iron industry were apprehended to better understand the place occupied by the iron artisans in the traditional society of Bam province

The blast furnace process for the reduction of iron ore to pig iron faces problems such as emission of air pollutants, high investment cost and the current major problem of decreasing supplies of coke. Coke is used in large quantities to promote a combination of direct and indirect reduction within the furnace. Due to the lack of good coking coal within South Africa, and dwindling supplies worldwide, new iron-making processes, are being developed using coal and/or natural gas to replace coke as the reductant. The new processes allow efficient use of carbon, fed in the form of coal pellets (coalbased processes) or natural gas (gas-based processes), as the reducing agent. Presently, most coal-based processes Use an excess of coal, up to 500% stoichoimetric addition, and are run at temperatures up to ±1200°C, although reduction tends to proceed at ±850°C. This project developed a low temperature process using mixed pellets of fine waste iron oxide and fine domestic coal with a natural carbonaceous binder (a by-product from local pulping industry). Reduction tests performed on composite pellets in a tube furnace and thermobalance indicated, upon analysis by X-Ray Diffraction and Scanning Electron Microscope, that reduction occurred gradually at 900°C. Implementing induction heating of bulk pellets reduced heating times substantially. Induction heating also resulted in direct reduced iron [DRI] containing 75 - 80% metallic iron. Energy consumption based on coal usage amounted to 23.71 GJ/ton DRI, which compares with the calorific consumption of most coal-based processes, i.e. coal consumption range between 15 and 25 GJ/ton DRI. Energy consumed during induction heating amounted to 9.94 GJ/ton DRI, as electricity. This energy consumption value does not take into account the efficiency of the primary energy required to generate electricity. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.

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Orientador: Pedro Wagner Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-18T17:40:51Z (GMT). No. of bitstreams: 1 RodriguesNeto_Anfrisio_M.pdf: 16512583 bytes, checksum: ab9ce169a14538fb39309ffc2574d6d9 (MD5) Previous issue date: 2011 / Resumo: A pesquisa procura mostrar as relações dos moradores da região do Morro de Araçoiaba e a construção da Real Fábrica de Ferro de São João de Ipanema no início do século XIX. O uso dos recursos naturais pela fábrica, como o minério de ferro (magnetita), as árvores para a feitura do carvão, combustível dos fornos e da água para mover as rodas, motivou uma série de atritos entre os moradores do Morro e a direção da Fábrica. A reserva da mata do morro 10 anos antes da construção da Fábrica e a retirada dos moradores para terras menos férteis iniciaram os embates. Os moradores eram em sua maioria pequenos proprietários e sitiantes que dependia dos recursos naturais, principalmente madeireiros e da terra para plantio de mantimentos. Por outro lado a Fábrica precisava destes sitiantes para fornecer comida à Fábrica, fazer o carvão para os fornos e braços para diversos serviços. A queima dos arvoredos mudou ecossistemas de várias espécies de pássaros e mamíferos. Afetou também a rica diversidade botânica repleta de árvores nobres. A pesquisa insere-se no campo metodológico da História Ambiental e para norteá-la valeu-se de levantamento realizado com pessoas que trabalham com educação na cidade de Sorocaba. O interesse dessas pessoas pela questão ambiental orientou a feitura do texto. Como resultados podemos destacar a forte intervenção do poder imperial português na região do Morro de Araçoiaba no início do século XIX e a resistência dos moradores. Apesar dos ordenamentos proibindo cortes e derrubadas, estas continuaram. Também mostra o impacto das instalações siderúrgicas na diversidade botânica e da fauna local que levou à extinção de várias espécies / Abstract: The research seeks to demonstrate the relations of the residents of Araçoiaba hill and the construction of the Royal St. John of Ipanema Iron Foundry, in the early XIX century. The use of natural resources by the plant, such as iron ore (magnetite), the trees for coal production, fuel for furnaces and water to move the wheels, resulted in a range of conflicts between the residents and the factory management. The reserve of the forest 10 years before the factory construction and the removal of the residents to a less fertile land started the conflicts. The residents were mostly small farmers, who depended on the natural resources, especially timber, and the land for planting provisions. On the other hand, the factory needed the small farmers to provide food to the factory, make the coal for the furnaces and as workforce for various services. The burning of trees changed the ecosystems of several species of birds and mammals. It also affected the rich botanical diversity, full of noble trees. This research is part of the methodological field of Environmental History. A survey was made with people who work in education in the city of Sorocaba. The interest of this people for environmental issues guided the formulation of the text. As a result, we can highlight the strong intervention of the Portuguese imperial power in the region of Araçoiaba hill, in the early XIX century and the resistance of the residents. Despite orders forbidding tree felling, they continued. The research also shows the impact of steel plants in the botanical diversity and in the local fauna, which resulted in the extinction of several species / Mestrado / Ensino e Historia de Ciencias da Terra / Mestre em Ensino e Historia de Ciencias da Terra