All raw waters contain microorganisms such as bacteria, fungi, virus, algae, which have the ability to reproduce and form a biofilm under favorable conditions, like on the surface of a reverse osmosis (RO) or nanofiltration (NF) membrane, where nutrients dissolved in the water accumulate. Like all the depositions on membrane surfaces, biofouling ma...

Irreversible membrane scaling caused by silica remains a severe problem in many reverse osmo-sis plants. The engineering task is to find out the appropriate anti-scalant agent and its optimal dosage. Because suitable test methods are missing, a new membrane-based test method was de-veloped. The fully automatically controlled test set-up and the tes...