Kumba Iron Ore Ltd is currently commissioning the Sishen Expansion Project (SEP) - a brownfields project on the Sishen Iron Ore Mine located in the Northern Cape Province, South Africa. SEP is designed to produce 13Mtpa of product from 21.7Mtpa of ROM feed. The beneficiation section of SEP employs jigs to process narrow size fractions in the 25x0.8mm size range. The -0.8mm fraction is screened out ahead of the jig plant and rejected as waste without any prior beneficiation. The processing of this fraction was not included in the early stages of SEP development because no suitable beneficiation or dewatering technologies could be identified within the time-frame required to implement SEP. This paper presents the SEP 1B project, i.e. the metallurgical and process engineering study that was done to evaluate the techno-economic viability of processing the -0.8mm material of SEP. To support this evaluation, metallurgical bench scale testwork was done on selected samples characterising the material types used in the SEP for gravity concentration beneficiation. Subsequently, pilot testwork on a 300-ton bulk sample demonstrated that an integrated teeter-bed/spiral circuit could be used to successfully beneficiate the -0.8mm fraction. The study has established the viability of the proposed process and has concluded that approximately 390 000 tpa could be produced and added to the SEP fine ore product without violating the applicable product specifications. The proposed process has been designed to be implemented in modular units in order to facilitate implementation and ensure future expandability. Based on the recommendations of the study, approval has been granted for the detail design feasibility study. Production is scheduled to commence in the first quarter of 2010.
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