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dc.contributor.advisorFick, J I J
dc.contributor.authorKleynhans, Ernst Lodewyk Johannes
dc.date.accessioned2017-12-14T10:13:42Z
dc.date.available2017-12-14T10:13:42Z
dc.date.issued2015
dc.identifier.urihttp://hdl.handle.net/10394/26100
dc.descriptionMEng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2016en_US
dc.description.abstractChromite ore mining is the only commercially viable source of new chromium (Cr) units. South Africa (RSA) holds the majority, approximately 75%, of the world’s exploitable chromite ore resources. The vast majority of mined chromite, approximately 90–95%, is consumed by the metallurgical industry for the production of different grades of ferrochrome (FeCr). The stainless steel industry consumes 80–90% of FeCr, primarily as high-carbon or charge grade. FeCr is vital to the production of stainless steel, an essential material in modern-day society of which the application and demand are growing. FeCr production is energy intensive, with huge amounts of electricity being consumed in the smelting process. In RSA, in particular, significant increases in electricity prices have placed pressure on FeCr producers. The pelletised chromite pre-reduction process is most likely the FeCr production process with the lowest specific electricity consumption (SEC), i.e. MWh/ton FeCr, currently in operation. However, due to increases in costs, efficiency and environmental pressures, FeCr producers applying the afore-mentioned process are still attempting to achieve even lower overall energy consumption. Recently it was proven that pre-oxidation of chromite ore, prior to pelletised pre-reduction, significantly decrease the SEC and lumpy carbonaceous reductants required for furnace smelting by increasing the process pre-reduction levels. Higher chromite pre-reduction levels correspond to lower furnace specific electricity and lumpy carbonaceous reductant consumption. This dissertation presents the first attempt at conceptualising the techno-economic feasibility of integrating chromite pre-oxidation into the current industrially applied pre-reduction process. Financial modelling yielded a net present value (NPV) of ~ZAR 1.9 billion at a 10% discount rate and an internal rate of return (IRR) of ~51%, suggesting that implementation of pre-oxidation prior to pelletised pre-reduction may be viable from a financial perspective. Sensitivity analysis indicated that the parameter with the greatest influence on project NPV and IRR is the level of pre-reduction achieved. This indicated that the relationship between maintaining the optimum pre-oxidation temperature and the degree of pre-reduction achieved is critical to maximise process efficiencyen_US
dc.language.isoenen_US
dc.publisherNorth-West University (South Africa) , Potchefstroom Campusen_US
dc.subjectChromite pre-reductionen_US
dc.subjectSolid state reduction of chromite (SRC)en_US
dc.subjectPre-oxidation of chromiteen_US
dc.subjectDiscounted cash flow (DCF) modelen_US
dc.subjectTechno-economic feasibilityen_US
dc.titleEconomic feasibility of a pre-oxidative process to enhance solid-state chromite reductionen_US
dc.typeThesisen_US
dc.description.thesistypeMastersen_US


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