Nonlinear Analysis of Heterogeneous Model for an Industrial Ammonia Reactor

Ammonia production is generally carried out in multiphase catalytic reactors. In this paper we analyze an industrial reactor for ammonia production with a dynamic heterogeneous model that accounts for transport resistance both inside and outside catalyst pellets. The work is aimed at investigating the possible appearance of periodic solutions in normal operating conditions for their relevance in terms of safety and control strategy. The analysis is based on a continuation approach to determine the bifurcational characterization of model predictions. This description is compared with that derived in a previous work (Mancusi et al. 2000), which was based on a simpler pseudo-homogeneous model of the same process.