Leaching processes may be described by two kinds of models—a micromodel that deals with changes to solid particles while they undergo leaching and a macromodel that deals with system changes. This article presents the micromodel by writing a general mathematical equation for single particle leaching, integrating this equation over all initial particle sizes and integrating over the residence time distribution applicable to the leaching system. The macromodel deals with material and heat balances and utilizes surface area integrals arising from the micromodel. The result is an overall model that describes both batch and continuous leaching in stirred tanks, and which may be expanded to include heap and dump leaching.
KeywordsLeaching Continuous Stir Tank Reactor Residence Time Distribution Micromodel Pulp Density
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