A review of froth flotation control

Abstract The last few decades have seen major advances in instrumentation and technology, and simplifications and modifications of new flotation plant designs. This has allowed for significant developments in process control. In particular, the development of base level process control (control of pulp levels, air flowrates, reagent dosing, etc.) has seen significant progress. Long-term, automated advanced and optimising flotation control strategies have, however, been more difficult to implement. It is hoped that this will change as a result of the development of new technologies such as machine vision and the measurement of new control variables, such as air recovery. This review looks at each of the four essential levels of process control (instrumentation, base level flotation control, advanced flotation control and optimising flotation control) and examines current and future trends within each sub-level.

[1]  John Ralston,et al.  The collectorless flotation and separation of sulphide minerals by Eh control , 1988 .

[2]  A. J. Thornton Cautious adaptive control of an industrial flotation circuit , 1991 .

[3]  Chris Aldrich,et al.  Machine Learning Strategies for Control of Flotation Plants , 1995 .

[4]  José Ragot,et al.  Modeling and control in the mineral processing industries , 1976 .

[5]  F Nicolls,et al.  Texture measures for improved watershed segmentation of froth images , 2004 .

[6]  M. Ruonal,et al.  Different aspects of using electrochemical potential measurements in mineral processing , 1997 .

[7]  John F. MacGregor,et al.  On the extraction of spectral and spatial information from images , 2007 .

[8]  D. A. Rice,et al.  The development of a color sensor system to measure mineral compositions , 1995 .

[9]  R. Pérez-Correa,et al.  Dynamic modelling and advanced multivariable control of conventional flotation circuits , 1998 .

[10]  Sirkka-Liisa,et al.  Simulation study of self-tuning adaptive control for rougher flotation , 1992 .

[11]  G. Forbes,et al.  Unsupervised classification of dynamic froths , 2007 .

[12]  Chris Aldrich,et al.  The interpretation of flotation froth surfaces by using digital image analysis and neural networks , 1995 .

[13]  Yang Li,et al.  A Classification of Flotation Froth Based on Geometry , 2007, 2007 International Conference on Mechatronics and Automation.

[14]  Antti J. Niemi,et al.  Simulation and control of flotation circuits , 1969, Autom..

[15]  N. Altun,et al.  Quantifying hydrophobicity of pyrite after copper activation and DTPI addition under electrochemically controlled conditions , 2004 .

[16]  John Ralston,et al.  Effect of collectors, conditioning pH and gases in the separation of sphalerite from pyrite☆ , 1998 .

[17]  Chris Aldrich,et al.  The classification of froth structures in a copper flotation plant by means of a neural net , 1995 .

[18]  John F. MacGregor,et al.  Froth-based modeling and control of flotation processes , 2008 .

[19]  Giuseppe Bonifazi,et al.  Characterisation of flotation froth colour and structure by machine vision , 2001 .

[20]  Jean-Pierre Celis,et al.  Electrochemical control of metallic copper and chalcopyrite-xanthate flotation , 1990 .

[21]  Warren J. Bruckard,et al.  The flotation of metallic arsenic as a function of pH and pulp potential — A single mineral study , 2007 .

[22]  Juan Yianatos,et al.  The long way toward multivariate predictive control of flotation processes , 2011 .

[23]  Chris Aldrich,et al.  Digital image processing as a tool for on-line monitoring of froth in flotation plants , 1994 .

[24]  W. Yen,et al.  Selective flotation of enargite from chalcopyrite by electrochemical control , 2005 .

[25]  James A. Finch,et al.  Industrial testing of a gas holdup sensor for flotation systems , 2003 .

[26]  James A. Finch,et al.  Gas dispersion measurements in flotation cells , 2007 .

[27]  Z. T. Mathe,et al.  Review of froth modelling in steady state flotation systems , 1998 .

[28]  F. Durão,et al.  Strategies for fuzzy control of a water/air column , 2000 .

[29]  Alexander Medvedev,et al.  Level control of cascade coupled flotation tanks , 2000 .

[30]  L.F.C. Jeanmeure,et al.  A CNN video based control system for a coal froth flotation , 1998, 1998 Fifth IEEE International Workshop on Cellular Neural Networks and their Applications. Proceedings (Cat. No.98TH8359).

[31]  K. Najim,et al.  Long-range predictive control of a rougher flotation unit , 1994 .

[32]  Stephen J. Neethling,et al.  Predicting and correcting grade-recovery curves: Theoretical aspects , 2008 .

[33]  Chris Aldrich,et al.  Online monitoring and control of froth flotation systems with machine vision: A review , 2010 .

[34]  C. Lara-Valenzuela,et al.  Metallurgical improvement of a lead/copper flotation stage by pulp potential control , 2000 .

[35]  Ruonala Mikko The Use of Electrochemical Mixed Potential Measurements for the Process Control and Expert System Development at the Hitura Mine , 1995 .

[36]  Daniel Hodouin,et al.  Nonlinear Predictive Control of a Rougher Flotation Unit Using Local Models , 1998 .

[37]  R. Pérez-Garibay,et al.  Neural networks to estimate bubble diameter and bubble size distribution of flotation froth surfaces , 2009 .

[38]  B. A. Wills XVI international mineral processing congress , 1988 .

[39]  F. F. Aplan,et al.  Coal flotation as a rate process , 1985 .

[40]  Daniel Hodouin,et al.  Economic optimisation of a flotation plant through grinding circuit tuning , 2000 .

[41]  Chris Aldrich,et al.  CHARACTERIZATION OF FLOTATION PROCESSES WITH SELF-ORGANIZING NEURAL NETS , 1995 .

[42]  Heikki Hyötyniemi,et al.  On characterization of pulp and froth in cells of flotation plant , 1997 .

[43]  M. He,et al.  Improvement of flotation behavior of Mengzi lead-silver-zinc ore by pulp potential control flotation , 2008 .

[44]  Ronald Woods,et al.  Electrochemical potential controlling flotation , 2003 .

[45]  Felipe Núñez,et al.  Hierarchical hybrid fuzzy strategy for column flotation control , 2010 .

[46]  Chris Aldrich,et al.  The monitoring of froth surfaces on industrial flotation plants using connectionist image processing techniques , 1995 .

[47]  Sameer H. Morar,et al.  Froth imaging, air recovery and bubble loading to describe flotation bank performance , 2007 .

[48]  M. Maldonado,et al.  An update on the estimation of the froth depth using conductivity measurements , 2008 .

[49]  Jan J. Cilliers,et al.  Recovery vs. mass pull: The link to air recovery , 2010 .

[50]  Jan J. Cilliers,et al.  The froth stability column : linking froth stability and flotation performance , 2005 .

[51]  Giuseppe Bonifazi,et al.  Prediction of complex sulfide flotation performances by a combined 3D fractal and colour analysis of the froths , 2000 .

[52]  J. A. Hamilton,et al.  Pulp level control for flotation — options and a CSIRO laboratory perspective , 2001 .

[53]  Stephen J. Neethling,et al.  Air-rate profile optimisation: From simulation to bank improvement , 2008 .

[54]  J. M. Hargrave,et al.  Diagnosis of concentrate grade and mass flowrate in tin flotation from colour and surface texture analysis , 1997 .

[55]  Sameer H. Morar,et al.  The use of a colour parameter in a machine vision system, Smartfroth, to evaluate copper flotation performance At Rio Tinto’s Kennecott Utah copper concentrator , 2005 .

[56]  Geoff Barton,et al.  Interaction between process design and process control: economic analysis of process dynamics , 1991 .

[57]  William L. Luyben,et al.  Essentials of Process Control , 1996 .

[58]  J-P. Franzidis,et al.  Quantifying contributions to froth stability in porphyry copper plants , 2009 .

[59]  Daniel Hodouin,et al.  Feedforward-feedback predictive control of a simulated flotation bank , 2000 .

[60]  Jan J. Cilliers,et al.  The froth stability column : Measuring froth stability at an industrial scale , 2006 .

[61]  L. G. Austin,et al.  A froth based flotation kinetic model , 1994 .

[62]  J. O Leppinen,et al.  Effect of electrochemical control on selective flotation of copper and zinc from complex ores , 1998 .

[63]  Taki Güler,et al.  Two-liquid flotation of sulphides: An electrochemical approach , 2007 .

[64]  Juan Yianatos,et al.  Short-cut method for flotation rates modelling of industrial flotation banks , 2006 .

[65]  Ruanne Delport,et al.  Process identification using second order Volterra models for nonlinear model predictive control design of flotation circuits , 2006 .

[66]  A. K. Siren The characterization of flotation by colour information and selecting the proper equipment , 1999, Proceedings of the Second International Conference on Intelligent Processing and Manufacturing of Materials. IPMM'99 (Cat. No.99EX296).

[67]  Jan J. Cilliers,et al.  An image processing algorithm for measurement of flotation froth bubble size and shape distributions , 1997 .

[68]  Antti Remes,et al.  Effect of speed and accuracy of on-line elemental analysis on flotation control performance , 2007 .

[69]  Kari Heiskanen,et al.  Study on using potentiostatic control in selective sulphide flotation , 1992 .

[70]  Mark A. Bennett,et al.  The investigation of bubble column and foam processes using electrical capacitance tomography , 2002 .

[71]  John F. MacGregor,et al.  Flotation froth monitoring using multiresolutional multivariate image analysis , 2005 .

[72]  Luis Bergh,et al.  Fuzzy supervisory control of flotation columns , 1998 .

[73]  Aldo Cipriano,et al.  An integrated system for supervision and economic optimal control of mineral processing plants , 1999 .

[74]  Nick J. Miles,et al.  Applying Froth Imaging Techniques to Assess Fine Coal Dewatering Behavior , 2006 .

[75]  Jan J. Cilliers,et al.  Calculation of the specific surface area in flotation , 2000 .

[76]  Douglas W. Fuerstenau,et al.  Electrochemical reaction control of contact angles on copper and synthetic chalcocite in aqueous potassium diethyldithiophosphate solutions , 1975 .

[77]  Väinö Hintikka,et al.  Potential control in the flotation of sulphide minerals and precious metals , 1995 .

[78]  Jean-Pierre Celis,et al.  Electrochemical control of chalcocite and covellite-xanthate flotation , 1990 .

[79]  Stephen J. Neethling,et al.  Simple relationships for predicting the recovery of liquid from flowing foams and froths , 2003 .

[80]  D. J. McKee,et al.  Automatic flotation control- a review of 20 years of effort , 1991 .

[81]  O. A. Bascur An interactive dynamic flotation model framework , 2000 .

[82]  Don W. Green,et al.  Perry's Chemical Engineers' Handbook , 2007 .

[83]  Francisco A. Cubillos,et al.  Identification and optimizing control of a rougher flotation circuit using an adaptable hybrid-neural model , 1997 .

[84]  Jan J. Cilliers,et al.  Detecting non-uniform foam density using electrical resistance tomography , 1999 .

[85]  Bertil Pålsson,et al.  Flotation of a complex sulphide ore I. : Cu/Zn selectivity control by adjusting pulp potential with different gases , 1996 .

[86]  D. W. Moolman,et al.  The identification of perturbations in a base metal flotation plant using computer vision of the froth surface , 1997 .

[87]  F. Durao,et al.  A neural network controller of a flotation process , 1995 .

[88]  W. Wang,et al.  Froth delineation based on image classification , 2003 .

[89]  F. F. Aplan,et al.  Model Discrimination in the Flotation of a Porphyry Copper Ore , 1985 .

[90]  A. Newell,et al.  Improving flotation recovery of copper sulphides by nitrogen gas and sulphidisation conditioning , 2000 .

[91]  Stephen J. Neethling,et al.  The relationship between the surface and internal structure of dry foam , 2009 .

[92]  Mehmet Polat,et al.  First-order flotation kinetics models and methods for estimation of the true distribution of flotation rate constants , 2000 .

[93]  James A. Finch,et al.  Continuous air rate measurement in flotation cells: Some fundamental considerations , 2006 .

[94]  Jayson Tessier,et al.  Application of numerical image analysis to process diagnosis and physical parameter measurement in mineral processes—Part I: Flotation control based on froth textural characteristics , 2006 .

[95]  Jan J. Cilliers,et al.  Flotation bank air addition and distribution for optimal performance , 2010 .

[96]  B. A. Wills,et al.  Wills' Mineral Processing Technology , 2005 .

[97]  Juan Yianatos,et al.  Supervisory control at salvador flotation columns , 1999 .

[98]  Weixing Wang,et al.  A robust bubble delineation algorithm for froth images , 1999, Proceedings of the Second International Conference on Intelligent Processing and Manufacturing of Materials. IPMM'99 (Cat. No.99EX296).

[99]  Enrique Luis Lima,et al.  Adaptive hybrid neural models for process control , 1998 .

[100]  Nick J. Miles,et al.  The use of grey level measurement in predicting coal flotation performance , 1996 .

[101]  Luis Bergh,et al.  Hierarchical control strategy for flotation columns , 1995 .

[102]  Jani Kaartinen,et al.  Optical spectrum based measurement of flotation slurry contents , 2008 .

[103]  Paolo Massacci Proceedings of the XXI International Mineral Processing Congress , 2000 .

[104]  R. A. Bearman,et al.  Expert systems: Opportunities in the minerals industry , 1992 .

[105]  Fernando O. Durão,et al.  Control of a flotation column using fuzzy logic inference , 2002, Fuzzy Sets Syst..

[106]  Zeki Aktas,et al.  Interpretation of the effect of froth structure on the performance of froth flotation using image analysis , 1998 .

[107]  Jan J. Cilliers,et al.  The relationship between the peak in air recovery and flotation bank performance , 2009 .

[108]  D. G. Hulbert Multivariable Control of Pulp Levels in Flotation Circuits , 1995 .

[109]  Kari Heiskanen,et al.  Effective flotation of a difficult nickel-ore based on intelligent mineral technology , 1993 .

[110]  Bogdan Filipič,et al.  Using inductive machine learning to support decision making in machining processes , 2000 .

[111]  Philip Thwaites PROCESS CONTROL IN METALLURGICAL PLANTS – FROM AN XSTRATA PERSPECTIVE* , 2007 .

[112]  J. H. Ahn,et al.  Color measurements of minerals and mineralized froths , 1993 .

[113]  Thomas Gustafsson,et al.  Modelling and control of a flotation process , 1999 .

[114]  J. Stout,et al.  Electrochemical flotation of sulfides: Reactions of chalcocite in aqueous solution , 1984 .

[115]  M. Suichies,et al.  An implementation of generalized predictive control in a flotation plant , 1998 .

[116]  Aldo Cipriano,et al.  A REAL TIME VISUAL SENSOR FOR SUPERVISION OF FLOTATION CELLS , 1998 .

[117]  J. Mosher,et al.  PT Freeport Indonesia's mass-pull control strategy for rougher flotation , 2008 .

[118]  John A. Meech,et al.  An advisory package for flotation operators using a real-time expert system , 1992 .

[119]  Emmanuel Manlapig,et al.  Modelling of froth transportation in industrial flotation cells: Part I. Development of froth transportation models for attached particles , 2004 .

[120]  Daniel Sbarbaro,et al.  Optimal control of a rougher flotation process based on dynamic programming , 2007 .

[121]  Aldo Cipriano,et al.  Assessment of expert fuzzy controllers for conventional flotation plants , 1999 .

[122]  Dee Bradshaw,et al.  Effective use of bubble size distribution measurements , 2006 .

[123]  Sirkka-Liisa Jämsä-Jounela,et al.  State of the art and challenges in mineral processing control , 2000 .

[124]  S. T. Hall,et al.  A Fractal Characterisation of the Structure of Coal Froths , 1998 .

[125]  Michael H. Moys Residence time distributions and mass transport in the froth phase of the flotation process , 1984 .

[126]  Mika Järvensivu,et al.  Integrated expert control system for grinding and flotation , 1993 .

[127]  a Gupta,et al.  Mineral processing design and operation , 2006 .

[128]  G. W. Barton,et al.  Synthesis and evaluation of alternative control schemes for a chalcopyrite flotation circuit , 1986 .

[129]  Sirkka-Liisa Jämsä-Jounela,et al.  Flotation process neural data analysis and on-line monitoring , 2000 .

[130]  Gun Berglund,et al.  Pulp chemistry in sulphide mineral flotation , 1991 .

[131]  Peter N. Holtham,et al.  On-line analysis of froth surface in coal and mineral flotation using JKFrothCam , 2002 .

[132]  Jan J. Cilliers,et al.  Dynamic froth stability in froth flotation , 2003 .

[133]  S. P. Barber,et al.  Effects of froth structure and mobility on the performance and simulation of continuously operated flotation cells , 1986 .

[134]  Sirkka-Liisa Jämsä-Jounela,et al.  Level control strategies for flotation cells , 2003 .