and the activity of each compound in the reactor stage is calculated as follows:
with Ppsatnx determined at the temperature of the boireactor.
Assuming that the applied conditions are far from the critical temperature and critical
pressure for each compound, and by applying the ideal gas law P.V=n.R.T, one can
obtain a good estimate of the total volumetric flow and the residence time in the
bioreactor.
(1/h at the temperature of the boireactor in K)
When a liquid/gas flash vaporisation technique is chosen, then precise control of the
different molar flows of each molecule entering in the composition of the gas must be
exerted. Figure 9.4 describes a solid/gas setup in which liquid substrates, water and
nitrogen are injected into a flashing unit for the realisation of the gas (Lamare and Legoy,
1999).
Thermodynamic control is then realised by calculating the different partial pressures
based on the different molar flows. When QN 2 and are well known,
can be determined and partial pressures can be calculated easily
by the following equation:
and thermodynamic activities are calculated according to equations previously described.
Multiphase bioreactor design 268