A kinetics-based mathematical model of the Peirce-Smith converter has been developed. The model considers mass transfer, heat transfer, and reactions between each of the phases present in the converter. Model validation is carried out using industrial data obtained from both copper and nickel converters. The model is generally able to predict the temperature and compositional variations of the converters to within the errors of the industrial data. However, the interactions between the white metal and slag during the copper blow are not understood sufficiently to model well.

The kinetics of minor element removal has been included in an overall model of the Peirce-Smith converter. Mass transfer between the condensed phases and to the gas has been considered. The model is able to predict the distribution of the minor elements fairly well but is limited by the scarcity of thermodynamic and kinetic data. It has been determined that the factors that increase oxygen efficiency, in particular gas velocity and tuyere submergence, tend to increase the proportion of the minor elements reporting to the dust. The reduction of the gas volume flow through the converter associated with oxygen enrichment does tend to reduce the minor element content in the dust. However, this effect may be offset by the increased temperature. Increasing temperature also increases the minor element content of the blister copper produced.

A sensitivity analysis of a kinetics-based model of the Peirce-Smith converter has been carried out, and the model has then been applied to an analysis of copper converter operation. The results of the sensitivity analysis indicate that only factors relating to the mass-transfer rates have a significant effect on the model predictions. However, even with large changes in diffusivities, the model predictions remain within the error of the plant measurements. The converter analysis indicates that considerable improvements to converter productivity can be made, particularly through changes to gas injection practices.

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