Patent ID: 7250108

Claim:
A method for measuring a local hydraulic permeability, Lpi, of a sub-group of hollow fibres of a bundle of hollow fibres mounted in a tubular casing, said casing having first and second ends and a first lateral opening at said first end, the bundle of hollow fibres being fixed in the casing by adhesive seals at said first and second ends, said adhesive seals being cut substantially perpendicular to a longitudinal axis of the bundle of hollow fibres to open a section of the bundle of hollow fibres, said method comprising the steps of: sealing the first end of the casing by pressing the casing on a plate to ensure a seal; applying a calibrated tube against a portion of the opened section of the bundle of hollow fibres to form a sealed connection between said calibrated tube and said portion of the opened section of the bundle of hollow fibres; passing a liquid having a flow rate through the first lateral opening of the casing; measuring a time t for the liquid to pass from a first graduation to a second graduation of the tube and calculating the local hydraulic permeability, Lpi, based upon: Lpi=V/tPSI whereby, V represents a volume of the tube between said first and second graduations; P represents a transmembrane pressure; and Si represents the surface area of the hollow fibres belonging to the sub-group to be measured.