The present invention includes a system and method for transferring a selected
solute species from a fluid mixture to a fluid media. The system of the present
invention includes a convergent channel for passing a fluid mixture containing
a selected species tangentially across the first surface of a porous membrane.
A fluid media is directed to flow tangentially over the second surface of the membrane.
As the fluid mixture and the fluid media flow on opposite sides of the membrane,
the selected species traverses the membrane leaving the fluid mixture and entering
the fluid media. The volumetric loss to the fluid mixture associated with the loss
of the selected species is compensated for by the convergency of the channel. As
a result a constant velocity is maintained over the membrane, maximizing the selectivity
of the filtration process.
