Model-based analysis of pressure oxidation autoclave behaviour during process upsets

Prediction of a hydrometallurgical reactor performance, process optimization and control apparently require reliable process models. Mathematical modelling of hydrometallurgical reactors is a rather complicated task. This is mainly caused by the particulate nature of processed materials, the simultaneous occurrence of several multi-phase heterogeneous reactions and the dependence of process parameters on working temperature. The most suitable technique for describing a process that involves particulate materials, is a special particle-counting procedure termed Population Balance Modelling (PBM). This procedure facilitates the investigation of both steady-state and dynamic behaviours of particulate processes. In this paper the pressure oxidation process serves as a case study to analyse the behaviour of a reactor (autoclave) when various process upsets occur. In practice, such upsets are triggered by sudden changes in oxygen mass transfer, oxygen feed rate, solids feed rate, cooling water injection, etc.