Rigorous dynamic modelling of complex reactive absorption processes

Reactive absorption processes usually represent kinetically controlled operations in which complex reactions are combined with multicomponent mass transfer. For this reason, an adequate theoretical description of reactive absorption should be based on the rate-based approach, with the direct consideration of the process rates. Along these lines, a rigorous;dynamic model allowing for multicomponent two-phase mass transfer, him and bulk reaction mechanisms, thermodynamic nonidealities, fluid dynamics and heat effects is developed. For systems including electrolytes, an additional account of the electrical potential gradient is involved. The whole dynamic rate-based model represents a system of partial differential equations which has to be;solved numerically. To validate the model, the reactive absorption of sour gases in an air purification process with packed columns is simulated. Several simulation results including different sensitivity studies are presented. The model is also tested against pilot-plant steady-state experiments. The simulation results are in good agreement with the experimental data. (C) 1999 Elsevier Science Ltd. All rights reserved.