Abstract
The pressure acid leach process is the most widely used method of metal extraction from laterite ores. The self-weight settling rate of the ore slurries governs the throughput of the process and is improved by adding synthetic polymers. The charge density, molecular weight, and dosage of the polymers are the key factors influencing the settling rate of the slurries. This interdisciplinary paper uses the geotechnical understanding of hindered sedimentation for a mining engineering application. A conceptual fuzzy rule-based model was developed to evaluate the initial hydraulic conductivity of polymer-modified laterite ore slurries. Identification of control parameters and selection of the model architecture (fuzzy rule-base) were based on expert judgment. The developed model was trained and validated using bench-scale settling test data. The model reasonably predicts the initial hydraulic conductivity of polymer-added laterite ore slurry with a coefficient of determination of 0.75. Rank correlation coefficient-based sensitivity analyses indicated that charge density was the most significant polymer parameter followed by molecular weight and then by dosage. Charge density accounted for more than 97% of variability in the initial hydraulic conductivity estimates for both anionic and cationic polymers.
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Acknowledgments
The authors are grateful to Dynatec Corporation and Ciba Specialty Chemicals for providing expert judgment and materials. Thanks to the University of British Columbia and the National Research Council of Canada for providing computing facilities.
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Azam, S., Sadiq, R. Evaluation of slurry settling rate using fuzzy rule-based modeling. Acta Geotech. 1, 149–156 (2006). https://doi.org/10.1007/s11440-006-0008-6
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DOI: https://doi.org/10.1007/s11440-006-0008-6