Dispersion in Chromatography Columns - Effect of Mobile Phase Compressibility On the HETP Equation for a Packed GC Column > Page 41

Now from D'Arcy's Law     

or                               

Thus,                            

Integrating from x=0 to x = L and Px = Pi to Po,

      

or                                      

Solving for (g),                                       (29)

Substituting for (g) in equation (27) from equation (29),

        

Thus the HETP equation given by equation (28) becomes