A mathematical model of the nickel converter: Part II. Application and analysis of converter operation

Abstract

In Part I[1] of this article, a mathematical model of the nickel converter was developed based on the assumption that the three phases in the converter vessel are in chemical and thermal equilibrium. In this article, a sensitivity analysis of the model is conducted to assess the uncertainties in model predictions and to delineate the critical process variables. Following from the equilibrium assumption, the rate-controlling process in the operation is the rate at which oxygen can be supplied to the matte. Routes to process improvement then lie in increased blast volumes or oxygen enrichment and improved operating procedures to reduce idle time. Temperature was not seen to exert a significant chemical effect on the process. More important to matte composition were variables such as ladle volume and cold charge composition. These variables directly affect either the matte volume or the overall bath composition and so are more important than those variables which have only an indirect effect through changing the conditions of equilibrium. An analysis of heat distribution in the furnace indicates the overwhelming fraction of heat removed by the off-gas.