A Study of Permeability and Diffusion at the Agglomerate-Scale in Heap (Bio)Leaching Systems

Abstract:

Multiple mini-column reactors, loaded with identically constructed ore samples representing grab samples of a larger heap, were used to study the behaviour of solution tracers to elucidate solution diffusion, dispersion and transport. The tracers were either introduced to the ore bed as a pulse, included during agglomeration of the ore or introduced to the system by submerging the ore bed. These methods of tracer introduction allowed for the characterisation of flow interchange in unsteady state systems. The resulting concentration-time distribution curves were analysed to allow characterisation of flow dispersion and diffusion, which facilitates exchange between the fast flowing and largely stagnant liquid phases. Preliminary results support the presence of distinct stagnant and flowing regions within the agglomerated ore bed. Agglomeration with the tracer promotes increased retention on the ore; potentially enhancing microbial transport via increased solution exchange after the initial period of attachment.

• Periodical: Advanced Materials Research (Volume 1130)
• Pages: 316-320
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1130.316
• Online since: November 2015
• Authors: Elaine Govender, Athanasios Kotsiopoulos, Sue T.L. Harrison*
• Keywords: Heap Bioleaching, Microbial Attachment, Microbial Colonisation, Solution Transport

References

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