TITLE:
Determination of Flow Structure in a Gold Leaching Tank by CFD Simulation
AUTHORS:
C. P. K. Dagadu, Z. Stegowski, L. Furman, E. H. K. Akaho, K. A. Danso
KEYWORDS:
Residence Time Distribution, Computational Fluid Dynamics, Navier Stokes Equations, Eulerian-Eulerian Multi-Fluid Model, RANS Standard k-ε Mixture Model, Multiple Reference Frame
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.2 No.7,
June
13,
2014
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.