Abstract: The invention relates to a method of producing membranes for nanofiltration, ultrafiltration or microfiltration modules which are intended, for example, for water treatment, said membranes comprising a hydrophobic polymer material having a hydrophilic polymer material incorporated therein or deposited thereon. The invention is characterised in that it comprises the following steps consisting in: (a) cold conditioning the membrane, following the incorporation or deposition of the hydrophilic polymer material, in a solution containing ammonium, sodium or potassium persulphate; and (b) hot crosslinking the hydrophobic and hydrophilic polymer materials forming the membrane, at a temperature greater than 60 DEG C, by soaking said membrane in a crosslinking agent employing a radical mechanism.

Abstract: A method of operating and monitoring a group of filter membrane modules connected in parallel and with the modules being periodically backwashed, in which:raw water to be treated is injected at a regulated pressure and the permeate outlet pressure is regulated to less than the inlet pressure;the group is provided with a water meter (60) on the raw water inlet duct and with three pressure sensors, one on the raw water inlet, one on the permeate outlet, and one on the backwash circuit, the meter and the sensors (100) delivering signals to a controller;each module is backwashed in succession with permeate from the other modules, with each module being individualized at that moment, thereby making it possible with aid of the water meter and of the pressure sensors to determine the permeability (150) in backwashing specific to the module as individualized in this way, and also to determine the production permeability of the remainder of the modules; andthe values determined in this way are compared with reference