Module 10 - Distillation

dist_ss.m Solves for the steady-state of the ideal binary distillation column by using fsolve.

Note: The fsolve function must be available. This is standard with MATLAB 4.x, but requires the optimization toolbox for MATLAB 5.x. To run this file, the user must first enter the global parameter vector DIST_PAR which has 8 elements. Note that the dynamic routine has 19 elements.

See Example M10.1.

%       the initial guess is a linear interpotion between 0.01 and 0.99
   x0 = 0.01:0.98/40:0.99;
   x0 = x0';
   x  = fsolve('dist_ss',x0);

dist_dyn.m Solves the dynamic equations that model the ideal binary distillation column, using ode45. See the file for definitions of each element of DIST_PAR.

See Example M10.2. Use the steady-state solution to generate the initial conditions. Now, step the reflux by 1%.

  DIST_PAR(12) = 0.02706;         % magnitude step in reflux
  DIST_PAR(13) = 5;               % time of reflux step change
  [t,x] = ode45('dist_dyn',[0 400],x0);  % MATLAB 5.x
  [t,x] = ode45('dist_dyn',0,400,x0);    % MATLAB 4.x