Determination of Flow Structure in a Gold Leaching Tank by CFD Simulation

C. P. K.  Dagadu; Z.  Stegowski; L.  Furman; E. H. K.  Akaho; K. A.  Danso

doi:10.4236/jamp.2014.27059

C. P. K. Dagadu^*, Z. Stegowski, L. Furman, E. H. K. Akaho, K. A. Danso

Abstract: Experimental residence time distribution (RTD) measurement and computational fluid dynamics (CFD) simulation are the best methods to study the hydrodynamics of process flow systems. However, CFD approach leads to better understanding of the flow structure and extent of mixing in stirred tanks. In the present study, CFD models were used to simulate the flow in an industrial gold leaching tank. The objective of the investigation was to characterize the flowfield generated within the tank after process intensification. The flow was simulated using an Eulerian-Eulerian multi-fluid model where the RANS standard kmixture model and a multiple reference frame approach were used to model turbulence and impeller rotation respectively. The simulated flowfield was found to be in agreement with the flow pattern of pitched blade axial-flow impellers that was used for mixing. The leaching tank exhibited good “off-bottom suspension” which reveals minimum deposition of gold ore particles on the bottom of the leaching tanks. Simulation results were consistent with experimental results obtained from a radioactive tracer investigation. CFD approach gave a better description of the flow structure and extent of mixing in a leaching tank. Hence it could be a preferred approach for flow system analysis where the cost of experimentation is high.

Keywords: Residence Time Distribution, Computational Fluid Dynamics, Navier Stokes Equations, Eulerian-Eulerian Multi-Fluid Model, RANS Standard k-ε Mixture Model, Multiple Reference Frame

Cite this paper: Dagadu, C. , Stegowski, Z. , Furman, L. , Akaho, E. and Danso, K. (2014) Determination of Flow Structure in a Gold Leaching Tank by CFD Simulation. Journal of Applied Mathematics and Physics, 2, 510-519. doi: 10.4236/jamp.2014.27059.

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