In the analysis of industrial flotation plant data ,itis advantageous to build a reliable computer based flotationmodel to be used in optimisation and design .A number of modelhave been proposed by many authors with each model havingvalue depending on the complexity of the situation for which itwas developed .Several of these models assume that a floatabilitydistribution of a mineral entering a flotation circuit can bedescribed by a number of floatability classes or components witheach of these components (and its flotation rate constant) beingconserved around the circuit .A non-linear optimisationprocedure for regressing floatability parameters (number offloatability components ,and the flotation rate constant of each)from laboratory batch flotation tests conducted on streamsaround the circuit has recently been devised [1].This paper outlines a technique to linearise the above regressionprocedure which improves the ease of solution and the level ofconfidence in the floatability parameter determination .Thetechnique also offers a strategy for determining the "optimum"number of floatability components.Dummy and real plant data were used to test the validity of thenew linear modelling technique. The dummy data were generatedusing a set flowsheet and a feed stream having two components(with set first order rate constants) to simulate the plant .Thesimulated data obtained were then fitted with the general linearmodel technique .The results of this operation show that thelinear modelling procedure can obtain the original model parameters very well.The model was then tested on real plant data from three typicalflotation plants. Again ,there is a very good correlation betweenstream experimental and model calculated recoveries based onthe feed to the circuit .The confidence limits of the modelparameters generated using this technique are reported .Theability to estimate parameter confidence intervals indicates whereadditional data (or an independent method) are required for moreaccurate parameter determination.The paper discusses areas where the technique is useful,including scale-up from pilot scale to a full scale flotationcircuits and determination of the effects of process plant variables.
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