Correlation between column flotation froth image features in respect to operational variables

Authors

1 Associate Professor, Dept. of Mining & Metallurgical Engineering, Amirkabir University of Technology, Tehran

2 Ph.D Student, Dept. of Mining & Metallurgical Engineering, Amirkabir University of Technology, Tehran

3 Assistant Professor, Dept. of Mining Engineering, Tarbiat Modares University, Tehran

Abstract

It is now generally accepted that froth appearance is a good indicative of the flotation operation conditions. Image analysis technology now offers a viable means of monitoring and control of the flotation process. In this paper, the relationship between the operational variables (i.e. gas flow rate, froth depth, slurry solids%, frother/collector dosage and pH) and the froth features (i.e. bubble size, froth velocity, froth colour and froth stability) in the column flotation was discussed during desulfurization of an iron ore using response surface methodology.Image analysis techniques have been developed and used successfully to characterize froth. Results of the CCD experiments showed that the flotation variables have different effects on the froth features. The effect of pH and the interaction of the effect of the pH and collector dosage have a significant impact on all mentioned froth features. The results show that the process state can be accurately deduced from the froth surface appearance, providing a convenient way to quantify changes in parameters as a function of the process control.

Keywords


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