Scale-up of the Dual Outlet Device
This paper discusses a new method to increase flotation recovery.As known from literature,fine and coarse panicles have different flotation rate constants,hydrodynamic behaviour and require different reagent regimes.The device discussed allows separate processing of finer and coarser slurry by extraction of a third stream,carrying finer slurry,from the flotation cell.By separate treatment of fine and coarse slurry operational conditions and so flotation recovery for both may be optimized more efficiently.Extraction and classification of the third stream is accomplished by low speed centrifugation and Taylor-Couette flow separation.This Dual Outlet Device (DOD) can be installed in a traditional flotation cell without need for equipment replacement.In order to asses different design options for the DOD a transparent laboratory scale model was built.For this scale model Computational Fluid Dynamics (CFD) simulations using the RANS k-εand LES turbulence models were performed.Essential insight in the dominant flow systems relevant to optimal operation of the DOD was obtained from the CFD simulations and flow visualization tests with the laboratory scale model.Based on these findings a number of configurations were investigated at pilot plant scale in a 5 m3 Outokumpu flotation cell.The results of the pilot plant study show that utilization of the DOD provides a method for in-cell control over particle size distribution in the slurry.Use of the DOD in a flotation cell may enhance flotation recovery and decrease flotation reagent consumption significantly,against marginal investment and operation costs.
Fines flotation CFD Particle classification
G.A.Wierink J.Tiitinen T.Niitti J.Turunen K.Heiskanen
Laboratory of Mechanical Process Technology and Recycling,Helsinki University of Technology,Material Science and Engineering,Espoo,Finland
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
4176-4182
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）