A double effect evaporator (Fig XXXXXXXXXXis fed at the solvent evaporation temperature corresponding to the feed mass concentrations xF for the first evaporator and x1 for the second. The volumes of...

A double effect evaporator (Fig. 3.18) is fed at the solvent evaporation temperature corresponding to the feed mass concentrations xF for the first evaporator and x1 for the second. The volumes of the liquid phase of both evaporators areV. The concentrations

of the solvate inside the evaporators are x1 and x2.

The evaporators have level control systems. The primary heating agent is steam with the latent heat l_v0
and the secondary heating agent is solvent with the latent heat l_v1. The solid fraction is contained only in the liquid phase being absent in the vapor one. The heat losses to the exterior are negligible. The steam and solvent are totally condensing and lose only their latent heat of vaporization l_v0
and l_v1. A steady state and dynamic model of the system is required.