|Home News Conferences Commodities Publications Business Directory Resources Help|
:: CFD Capabilities Advance Thickener Efficiency and Environmental Benefits
Mining companies grappling with the need to maximise efficiencies to combat recession have found a strong ally in the technology Computational Fluid Dynamics (CFD).
CFD is becoming particularly useful in optimising the design and function of thickeners, which are becoming increasingly important in meeting efficiency and environmental demands including conserving water and chemicals.
CFD advances the previously acceptable rudimentary understanding of thickener flow patterns to a new level, says Outotec. This greatly expanded understanding sets a new benchmark for the future of thickener modelling.
“CFD allows proposed thickener designs to be truly customised and optimised for individual duties, resulting in enhanced mixing, energy dissipation, flocculation, solids distribution and shear rates," says Outotec, which recently established an in-house thickener CFD team to help clients capitalise on the many gains available through it.
“CFD capabilities take a large amount of risk out of thickener designs because they eliminate mistakes before they become reality," says Dr Alex Heath, Principal Research Engineer, Thickener CFD and Process Modelling at Outotec.
“Because every thickener is unique - thickener functions and designs are so different from each other - it is enormously beneficial to accurately calculate in advance what is going to work and what is not.
“Instead of a mistake in feedwell design costing hundreds of thousand over the operation life due to inefficiencies, the possibility of this happening can be eliminated for a fraction of that cost. Our CFD team, lead by highly experienced modellers, can quickly, accurately and cost-effectively produce optimal designs, taking the guesswork out of design geometry options.
“This unique CFD capability, backed by decades of real life experience, ensures thickener designs are accurately predicted. This in turn produces truly optimised thickener performance and avoids costly design mistakes.
“CFD is particularly useful in such critical areas as overflow clarity, underflow density and throughput. These, in turn, are critical to water and chemical conservation, which are important for both economical and environmental reasons."
After a number of years investing in feedwell CFD research and development using such centres as CSIRO and others, Outotec developed break-through feedwell designs using the science. To continue this work, Outotec established its in-house thickener CFD capability by recruiting Dr Heath, a CFD modeller with 10 years experience in the AMIRA P266 research project “Improving Thickener Technology”. AMIRA P266 is supported by many of Australia’s major mining and mining supply companies, attracting millions of dollars in investment.
Using cutting edge CFD, Outotec developed the industry’s first major feedwell innovation in over 15 years. The Vane FeedwellTM, incorporates several global patents into its unique design and has quickly shown its value in ‘real life’, ensuring highly efficient thickener operation. The Vane FeedwellTM is now the global standard on all Outotec thickeners.
It is quite rare for thickener suppliers to invest in such comprehensive in-house CFD capabilities, as they mostly outsource, but Outotec believes this investment quickly pays dividends, with CFD becoming, more and more, the way of the future. Outotec clients are already benefiting from this in-house CFD capability, with projects ensuring their thickener designs are CFD-optimised for full performance potential. The CFD team, globally responsible for all of Outotec’s CFD thickening activity, is based in its Perth office and lead by Richard Triglavcanin, Global Technology Manager - Thickening.
Outotec has also invested in the latest StarCD parallel processing software and multi-processor hardware. This gives Outotec full Eulerian multi-phase CFD capability, and the ability to model turbulent stratified buoyant particle laden flows, which occurs in the feedwell and top half of a thickener, says Dr Heath.
“The CFD simulation capability is combined with many years experience in interpreting the results in terms of key parameters like: mixing, energy/momentum dissipation, flocculation, feedwell discharge symmetry, solids distribution and laminar/turbulent shear rates. Outotec uses CFD as part of both its internal R&D programs and to give confidence in individual unit installations.
© 1998-2017, Minerals Engineering International