Page 90 - Separation process engineering
P. 90
The fourth question is: How should we do the individual convergence steps? For the Rachford-Rice
equation, linear interpolation or Newtonian convergence will be satisfactory. Several methods can be
used to estimate the next flash drum temperature. One of the fastest and easiest to use is a Newtonian
convergence procedure. To do this we rearrange the energy balance (Eq. 2-7) into the functional form,
(2-51)
The subscript k again refers to the trial number. When E is zero, the problem has been solved. The
k
Newtonian procedure estimates E k+1 (T drum ) from the derivative,
