Process for filtering a liquid by tangential flow along a membrane and periodic unblocking

摘要

Process consisting in making a liquid flow tangentially along a porous and permeable membrane which is periodically unblocked by a back flow of a fraction of a liquid or of the permeate through the membrane. It is characterised in that the unblocking operation is performed according to the following stages: - backflow of the permeate by reversal of flow at a flow rate of higher value than that of a reference flow rate for normal filtration, - progressive decrease in the back flow rate, - stabilisation of the said flow rate, - slow return to the reference flow rate in a normal filtration direction, opposite to that of the back flow.