Unsteady state treatment of very lean waste gases in a network of catalytic burners

Catalytic reactors in forced non-stationary operation enable autothermal VOC oxidation even at extremely low adiabatic temperature rise. A network of three reactors in series with large inert sections is presented as an alternative to the reverse-flow reactor. A one-dimensional model for simulation of VOC oxidation in forced non-steady state packed bed catalytic reactors has been developed and implemented into a program that uses standard mathematical software. Numerical simulation reveals that the network of three catalytic reactors in series with large inert sections is a suitable design for VOC oxidation at low concentration. The system can be controlled by a simple set of two switches acting according to temperature setpoints. Maximum temperature is very sensitive to heat transfer, which cannot be considered as infinitely fast despite small temperature gradients between gas and solid. These dependencies are somewhat less pronounced at higher load. (C) 1999 Elsevier Science B.V. All rights reserved.