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Durante as etapas de processamento mineral, na maioria dos casos, há o envolvimento de suspensões - misturas de minério fino com uma fase líquida. Logo, as operações de processo são influenciadas pela resistência dessas suspensões em se deformar ou fluir, quando submetidas a forças de cisalhamento ou pressão, ou seja, a viscosidade da suspensão influenciará nas etapas de processamento. Nesse trabalho, será feita uma revisão sobre reologia de suspensões e o processamento mineral. Serão abordados aspectos conceituais sobre reologia de suspensão e suas variáveis, classificação reológica dos fluidos e determinações de viscosidade através do viscosímetro rotacional de cilindro concêntrico.
Mineral processing is often carried out on suspensions (usually a mixture of solid particles and liquid). The process is influenced by the resistance to flow resulting from a shear stress or pressure applied in the fluid (suspension). Therefore, the viscosity of suspensions will affect the mineral process. This paper reviews the applications of rheology in mineral processing. This review focuses on conceptual aspects such as fluid classification, variable of rheology and measurements with concentric viscometer

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The successful use of anaerobic reactors for bioremediation of acid mine drainage has been shown in systems with neutral pH. However, the choice of an efficient and suitable process for such wastewater must consider the capability of operating at acidic pH and in the presence of metals. This work studies the performance of an anaerobic batch reactor, under conditions of varying initial pH for its efficiencies in sulfate removal and metal precipitation from synthetic acid mine drainage. The chemical oxygen demand/sulfate (COD/SO4(2-)) ratio used was 1.00, with ethanol chosen as the only energy and carbon source. The initial pH of the synthetic drainage was progressively set from 7.0 to 4.0 to make it as close as possible to that of real acid mine drainage. Metals were also added starting with iron, zinc, and finally copper. The effectiveness of sulfate and COD removal from the synthetic acid mine drainage increased as the initial pH was reduced. The sulfate removal increased from 38.5 ± 3.7% to 52.2 ± 3%, while the removal of organic matter started at 91.7 ± 2.4% and ended at 99 ± 1%. These results indicate that the sulfate reducing bacteria (SRB) community adapted to lower pH values. The metal removal observed was 88 ± 7% for iron, 98.0 ± 0.5% for zinc and 99 ± 1% for copper. At this stage, an increase in the sulfate removal was observed, which reaches up to 82.2 ± 5.8%. The kinetic parameters for sulfate removal were 0.22 ± 0.04 h(-1) with Fe, 0.26 ± 0.04 h(-1) with Fe and Zn and 0.44 ± 0.04 h(-1) with Fe, Zn, and Cu.