THE OPTIMIZATION OF THE CIP PROCESS USING MATHEMATICAL AND ECONOMIC-MODELS

A number of developments in the modelling of the carbon-in-pulp (CIP) process are described. The issues affecting the modelling of adsorption are examined, and an appropriate adsorption model is briefly described. Data collected from a large plant confirms the predictive ability of the model. A preliminary model for the AARL elution process is also described. The model is based on the assumption that the elution behaviour of gold is dominated by the changing sodium concentration during the washing cycle of this process. The model was fitted to data obtained from an industrial elution plant. Acceptable agreement between model predictions and experimental data was found. However, the model is preliminary in nature and is not yet a useful tool for plant optimization. More research is required in order to develop the model to an appropriate stage. A case study is presented, in which it is desired to design an adsorption plant which provides optimum financial return, when treating a very low-grade stream. This is successfully achieved by using the adsorption model in conjunction with an economic model which allows adsorption and elution capital and operating costs to be estimated for a large number of plant configurations.