RHEOLOGICAL BEHAVIOR OF NICKEL LATERITE SUSPENSIONS

Studies have been conducted on rheology of nickel laterite suspension at different temperatures, concentrations, particle sizes and pH for b oth fines and tailings from a hydrocyclone discharge. Fine laterite sl urries exhibit a Bingham plastic behaviour at 20% (w/w) solid concentr ation and above, while the same behaviour is observed for tailing slur ries at > 25% (w/w) solid concentration. It is also observed that rheo logical parameters are affected by both pH and temperature. Both the B ingham viscosity and yield stress are minimum at around pH = 7 and the viscosity decrease with temperature is between 2- and 3-fold within t he experimental range (20-60 degrees C). Further it is also observed t hat there is a steep increase in viscosity and yield stress between 45 and 50% (w/w) solid concentration. Correlations have been obtained fo r predicting both Bingham viscosity and yield stress taking into consi deration, a non-dimensional parameter C-w/C-w,C-max, specific surface area and d(50). (C) 1998 Elsevier Science B.V. All rights reserved. di scharge.