Integrated multi-objective membrane systems application of reverse osmosis at the Amsterdam Water Supply

Within the scope of a project funded by AWWARF and USEPA three very promising IMS's were identified for surface water treatment. This paper will cover some highlights of the research carried out by Amsterdam Water Supply (AWS) and Kiwa on the combination of biological activated carbon filtration, slow sand filtration and (ultra low pressure) reverse osmosis. Primary objectives of this IMS study are restriction of (bio)fouling, productivity control, disinfection and removal of DBP-precursors. To prevent fouling two pretreatment schemes were tested. The reference scheme consisting of coagulation, sedimentation, rapid sand filtration and slow sand filtration lowered the MFI to 2 s/l 2. The alternative scheme consisting of the reference scheme extended with ozonation and biological activated carbon filtration before slow sand filtration lowered the MFI to 1 s/l 2. Biofouling was characterized by AOC and biofilm formation rate. Average AOC values were low (