Determination of optimal performance and revenue of flotation circuits by process simulation

• Main Author: de Graaf, Dayell
• Other Authors: Sand, Anders, Kemian tekniikan korkeakoulu, Serna, Rodrigo, Aalto-yliopisto, Aalto University
• Format: Master Thesis
• Language: English
• Published: 2018
• Subjects: flotation circuit; HSC Sim; economic evaluation; flotation cells; Copper Mine; Northern Sweden
• Online Access: https://aaltodoc.aalto.fi/handle/123456789/33760

The use of high volume flotation cells has nowadays become more and more common to deal with the production of high capacity, low-grade open pit mines, which are typically copper or gold mines. Several identical cells are preferred over cells with size and dimensions optimised for their purpose within the circuit. This is done with the purpose to minimise investment costs, simplify process operations and reduce maintenance costs. However, the implementation of large flotation cells in the mineral beneficiation process holds several financial benefits, but gives no guarantee of an equal or improved metallurgical performance. Historically, flotation plants have been designed based on the results of laboratory tests, multiplied with an up-scaling factor for industrial scale adjustment. Boliden has therefore been working on the scaling of flotation cells and investigating the role of circuit design for improved process performance and optimised business cases. This relationship is studied to provide economic calculations for selected cases of circuit design where estimates of investment and operational costs are combined with the estimated process performance of alternative simulated circuit designs. This work includes combining this information for generating business case examples, which have been evaluated and compared for more in-depth understanding of economic optimisation of circuit design. The optimization of flotation equipment combinations has been investigated based on comparisons between concentrate performance and financial models of large-scale industrial flotation cells in Boliden’s Aitik copper mine in Northern Sweden. The expected trend of decreased investment and operating costs was observed in the proposed cases. The calculated cash flow of copper mineral processing at the simulated plant can obtain a return on investment within 4.5 years, which 2.5 years earlier than the current plant would be able to. It was found that the probability of NPV exceeding 0 within five years according to ...