Can we Ignore Pressure Drop in Catalytic Fixed- Bed Reactors?
In catalytic fixed-bed reactors, which is known as work-horse of chemical industry, one can experience a
significant pressure drop. Ignoring such a pressure drop may end up with unexpected reactor performance.
In this simulation study, we considered two differential equations, one coming from mole balance, and the other from Ergun
= ′ (mole balance)
+ 1.75(Ergun Equation)
These two differential equations are solved simultaneously for a 2nd-order gas phase reaction with no mole changes using
MATLAB package program. Parameters that changed were CA0 (initial concentration), k (specific reaction rate), v0 (initial
volumetric flow rate of gas), and α (a constant which is function of particle diameter, bed porosity and viscosity). The
following simulation results are obtained and only conversions versus volumetric flow rates are shown graphically in the
main text. The rest of the results are just mentioned in words. Findings are:
1) Whenvo goes up, conversion, X, goes down for both with and without pressure drop. Conversion is less with
pressure drop than the case when ΔP=0.
2) When kincreases, the effect of ΔPon conversion is much more pronounced.
3) WhenCA0 increases, the effect of ΔPon conversion is much more pronounced.
4) When α goes up,ΔP goes up too, hence the conversion is less for the same catalytic bed.
Keywords: Packed bed reactors, Pressure drop, Reactor simulation, catalytic reactors