• **Permeability of a membrane (Lp)**


The permeate flow (Jv) characterizes the productivity and is expressed as follows:

$$J\_v = L\_p \left(\Delta P - \sigma \Delta \pi\right) \tag{2}$$

The permeability of the membrane is deduced from the slope to the right of the permeate flow Jv as a function of the transmembrane pressure ΔP.
