Document Type: Research Paper
Reseaarch Institute of Biomolecular and Chemical Engineering, University of Pannonia
Research Institure of Bio-molecular and Chemical Engineering, University of Pannonia
Research Institute of Bio-molecular and Chemical Engineering, University of Pannonia
Knowing the overall solute ﬂux and the partial ﬂuxes expressed by every single transport layer, the membrane internal interface concentrations can separately be expressed. Both the overall transport coefcient and the driving force strongly depend, among others, on the value of the structural parameter and the water permeability. Study of the interface concentrations as a function of the membrane characteristic properties and the operation conditions shows clearly the diﬀerent, individual eﬀects of the Cm, Cs interface membrane concentrations (and Csp) on the concentration diﬀerence across the membrane active layer and thus on the process efciency. The change of the value of Cs is much more sensitive on the membrane transport properties than that of the value of Cm. The high value of the structural parameter essentially destroys the membrane performance accordingly eﬀorts of the manufacturers must be focused on lowering of its value for increase of the water permeability. The membrane performance can also be improved not only by its characteristic properties, but by the operating conditions as well, e.g. by applying diﬀerent solute concentrations instead of seawater-river water pair. The higher draw solute or lower feed concentrations can serve then much higher power density. The knowledge of the individual interface concentration of every single transport layer enables the user to do more deep, more precise study of the mass transfer process during pressure retarded osmosis. Finally, it is shown reasonable agreement between the measured and predicted data.