Maintaining carbon activity is critical to the satisfactory recovery of gold in the Carbon- in-Pulp (C.I.P.) process. Reduced activity can lead to gold losses in tails and lower tonnage throughput._x000D_
Carbons from a number of W.A. C.I.P._x000D_
circuits have been examined for the extent of fouling by inorganics such as calcium, magnesium, copper, nickel and silicon. Many of these carbons have exceedingly low activity leading to low gold loading and excessive contact times._x000D_
The relative importance of these fouling agents and cyanide levels on carbon activity is discussed. Mathematical modelling shows that relatively small improvements in kinetic activity lead to much lower tank volume require- ments and carbon residence times.