Abstract: “The aim of the study is to evaluate the simultaneous effect of salinity and hydrocarbons on the performances of two parallel Moving Bed-Membrane BioReactor (MB-MBR) systems fed with real saline oily wastewater(slop). Different dilution factors were considered during the experiments. The first analysed MB-MBR system was characterized by the use of Linpor® carriers (MB-MBRI), the other one by AnoxKaldnesTMK1 carriers(MB-MBRII); in both systems an ultrafiltration membrane was used. The results showed a decrease of biological removal efficiencies for both systems mainly due to the total petroleum hydrocarbons (TPHs) playing an inhibitory role in the biomass growth; this was confirmed by negligible efficiencies in the removal of the TPHs. The analysis of the extracellular polymeric substances (EPSs) has highlighted a reduction of bound EPSs and a simultaneous increase of the protein fraction of the soluble microbial products (SMPs) likely due to the cellular lysis, as response to the increa”

Keywords: biofilm; EPS; fouling; MBR; salinity; slops; TPH