User:Tempuser1337/sandbox

Levenspiel Plot Levenspiel Plots are very useful plots when considering reactor design. For ideal reactors if plotting FA0/rA vs Fractional conversion a Levenspiel Plot is made. This can be used to quickly and easily calculate the volume of various types of reactors.

PFR
To simulate a plug flow reactor (PFR) on a Levelspiel Plot the area under the curve is measured and the area is taken as the volume of a PFR necessary to achieve that fractional conversion. For most common reactions the PFR will be a better option than a CSTR if it is assumed that price is proportional to size. Some exceptions are discussed later on.

CSTR
Continuous stirred tank reactors (CSTRs) on a Levenspiel Plot a volume can be calculated by taking the area of a box from the final fractional conversion back to the fractional conversion entering the CSTR (frequently 0).

Autocatalytic Reactions
With autocatalytic reactions it is more effective to put a CSTR and a PFR in series to minimize volume. This is because autocatalytic reactions have a parabolic shape. Thus to minimize volume at low conversions the CSTR should be used as the volume is calculated at final conversion. A PFR would need to integrate the additional area from the curve down to the top of the box. However at high conversions a PFR is more effective as it can ignore the area above the curve. Thus using a CSTR into a PFR minimizes the volume required. Other cases that may not follow the ideal scenario that Levenspiel Plots model would be adiabatic reactions that are either exothermic or endothermic. This is because reaction rate is frequently dependent upon the temperature of the vessel and depending on the heat transfer possible with a reactor the rate can be different from what is predicted by the Levenspiel Plot.