Efficient and robust method for numerical analysis of dead zone in
catalyst particle and packed bed reactor.
Abstract
For two processes of large importance, catalysis and biocatalysis, were
reported zones without reactants, so called dead zone (DZ). They results
from diffusional transport limitations, when apparent reaction order is
between (-1..1). Formation of DZ reduces effectiveness of catalyst and
influence packed bed reactor productivity. For simple reaction kinetic
model, a DZ width inside a pellet can be calculated analytically solving
appropriate differential mass balance model. However, generally the
analytical solution is unknown and only with using numerical method the
position of DZ can be established. The problem with DZ appearance
belongs to problems with moving boundaries. Its solution requires
application of special numerical procedure and relatively long CPU time.
In this work it was proposed a simple, very fast numerical method for
calculation of DZ position inside pellet. The method proposed combined
with orthogonal collocation on finite elements can be applied for
analysis of work of packed bed reactor.