Evaluation of emerging contaminants in a drinking water treatment plant using electrodialysis reversal technology.

Emerging contaminants (EC) have gained much attention with globally increasing consumption and detection in aquatic ecosystems during the last two decades from ng/L to lower ug/L. The aim of this study was to evaluate the occurrence and removal of pharmaceutically active compounds (PhACs), endocrine disrupting chemicals (EDCs) and related compounds in a Drinking Water Treatment Plant (DWTP) treating raw water from the Mediterranean Llobregat River. The DWTP combined conventional treatment steps with the world's largest electrodialysis reversal (EDR) facility.

Full-scale validation of an air scour control system for energy savings in membrane bioreactors.

Membrane aeration represents between 35 and 50% of the operational cost of membrane bioreactors (MBR). New automatic control systems and/or module configurations have been developed for aeration optimization. In this paper, we briefly describe an innovative MBR air scour control system based on permeability evolution and present the results of a full-scale validation that lasted over a 1-year period.

Towards integrated operation of membrane bioreactors: effects of aeration on biological and filtration performance.

Two experimental studies evaluated the effect of aerobic and membrane aeration changes on sludge properties, biological nutrient removal and filtration processes in a pilot plant membrane bioreactor. The optimal operating conditions were found at an aerobic dissolved oxygen set-point (DO) of 0.5 mg O2 L(-1) and a membrane specific aeration demand (SADm) of 1 m h(-1), where membrane aeration can be used for nitrification.

Biological treatment and thickening with a hollow fibre membrane bioreactor.

Aerobic operation of an immersed hollow fibre membrane bioreactor, treating municipal wastewater supplemented with molasses solution, has been studied across mixed liquor suspended solids (MLSS) concentrations between 8 and 32 g L(-1), the higher concentrations being normally associated with thickening operations. Only a marginal loss in membrane permeability was noted between 8 and 18 g L(-1) when operation was conducted without clogging. The sustainable operational flux attainable above 18 g L(-1) was highly dependent upon both the MLSS concentration and the state of the membrane.

Assessment of energy-saving strategies and operational costs in full-scale membrane bioreactors.

The energy-saving strategies and operational costs of stand-alone, hybrid, and dual stream full-scale membrane bioreactors (MBRs) with capacities ranging from 1100 to 35,000 m(3) day(-1) have been assessed for seven municipal facilities located in Northeast Spain. Although hydraulic load was found to be the main determinant factor for the energy consumption rates, several optimisation strategies have shown to be effective in terms of energy reduction as well as fouling phenomenon minimization or preservation. Specifically, modifications of the biological process (installation of control systems for biological aeration) and of the filtration process (reduction of the flux or mixed liquor suspended solids concentration and installation of control systems for membrane air scouring) were applied in two stand-alone MBRs.