Flow Reactor - Modeling and Simulation
Flow Reactor Modeling and Simulation - Model the fluid mixing
characteristics of large scale storage vessels with the interactive Residence
Time Distribution Curve Simulator.
Perfectly Mixed Flow:
In a Perfectly Mixed Flow reactor there are no spatial
gradients of temperature or of material concentration. A perfectly mixed flow
reactor may be modellized by an exponential decay curve as indicated.
Non Ideal Flow:
In a real fluid mixing reactor the flow may inlude zones such as: i) flow re-circulation, ii) Stagnant
flow or dead volume and iii) flow short circuiting. Non ideally mixed flow can be modellized by RTD curves.
Residence Time Distribution Curves:
RTD curves involve the injection of a conservative
tracer to the inlet stream of a fluid mixing reactor. RTD curves may be used to fit a reactor model that describes the real
flow characteristics of the fluid mixing vessel.
Input: Tank Volume
C0 - Initial Concentration
Input: Tank Flow Rate
T - Nominal Residence Time
For example, a tank may be
described as a re-circulating flow reactor with 10% dead volume. Subsequent design modification and reactor model analysis may lead to the elimination/reduction of unmixed zones thereby leading to a more efficient mixing process.
re-circulating flow reactor non-uniform dispersion of the incoming particles, and both
chemical and turbulent diffusion will take place leading to an imperfectly mixed
tank. A single non-ideal tank may be modelled as a number of
(n) smaller ideally mixed reactors in series with flow re-circulation.
Plug Flow: The output response from an ideal Plug Flow vessel will be identical to
that of the input stimulus. If a unit pulse of tracer were injected into a
vessel in which dispersion and diffusion do not take place, then after a time delay equivalent to the
Nominal Residence Time (T) of the vessel, a unit pulse response would be recorded at the outlet stream.
Residence Time Distribution: For ideal plug flow within a vessel all
fluid elements will spend the same amount of time in the system. Non ideal flow
through a container will have a distribution of residence times.