A probalistic model for the intrusion of solid fines in activated carbon

The carbon-in-pulp (CIP) process is used extensively in the mining industry to recover dissolved gold from cyanide-leached pulps. The pulp normally co ntains inorganic material that could penetrate the pores of the carbon. In the formulation of the model it was proposed that the loading of solid spec ies from the hulk suspension onto activated carbon is dependent on differen t probabilities such as the activity of pores at the outer shell of the car bon, the concentration of fines in suspension, the stirring speed of the su spension, zeta potential of solid fines, and the fraction of fines smaller than the size of a specific pore. The proposed model was shown to describe the intrusion of solid fines in ca rbon accurately under a wide variety of conditions. The model was not so se nsitive towards zeta potential of the solid particles or the effective stir ring speed. The concentration of solid fines in the suspension influenced t he collision-kinetics and hence the rate of intrusion. The concentration de cay of solid fines in suspension was very sensitive at low concentrations, whereas at high concentrations the model-output concentration remained cons tant.