Patent ID: 7698928

Claim:
A process for detecting defects in a membrane filtration system having at least one spiral wound hyperfiltration module in a vessel comprising the three sequential steps of: a. passing a first feed liquid across the surface of a membrane while applying pressure to said first feed liquid so that a permeate solution and a reject solution are produced; b. introducing a second feed liquid under pressure, said second feed liquid containing a challenge species, the concentration of said challenge species being at least twice as high in said second liquid as compared to said first liquid, and wherein said challenge species is selected from at least one of: i) a divalent anion, and ii) a fluorescent particle of a diameter greater than 0.005 microns; c. introducing a third feed liquid under pressure, wherein the successive introduction of said second and third feed liquids result in a pulse of challenge species characterized by a concentration profile in time for said challenge species having FWHM of less than four minutes; and further comprising: d. detecting and recording the relative concentration of said challenge species within said permeate solution as a function of time, and e. evaluating the integrity of said filtration system by comparing the recorded time dependent concentration of said challenge species with said permeate solution to a reference.