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Effect of carrier texture and type on biofilm development and maturation were studied on an eight-reactors-containing pilot-scale cascade system which treated municipal wastewater under aerobic conditions and various system operational characteristics. Dissimilarities in the biofilm structures grown on four types of polymer fiber-based carriers placed in the reactors having different role during wastewater purification and compositional changes of bacterial communities during biofilm maturation were clearly observable. In the first 2–3 weeks, taxonomic diversity of biofilm bacterial communities increased and reached their maximum values. Carrier type and texture had comparable effect on the weight, activity and composition of biofilms as the wastewater matrix. Biofilm community grown on the carrier having the best colonization properties were dominated by Proteobacteria, Synergistetes, Bacteroidetes and Firmicutes. In the nascent 7-days-old biofilm, aerobic chemoorganotrophic genera, while in the mature 45-days-old biofilm anaerobes, such as sulfate-reducer and fermentative genera were the major members of the bacterial communities.

Due to the increasing amount of persistent organic pollutants (POPs) in general and pharmaceutical residues in particular in municipal wastewater, the efficiency of water treatment technologies should be improved. Following the biological treatment of wastewater nanofiltration offers a possible way for the removal of POPs. In this study β-cyclodextrin containing nanofilters having different chemical composition and thickness (1.5–3.5 mm) were investigated. For their characterization, their adsorption capacity was determined applying ibuprofen containing model solution and total organic carbon (TOC) analyzer. It could be established that the regeneration of nanofilters with ethanol and the application of inorganic additives (NaCl, NaHCO3, NH4HCO3) increased the adsorption capacity of nanofilters. The best results were achieved with chemical composition of 30 m/m% β-cyclodextrin polymer beads and 70 m/m% ultra-high molecular weight polyethylene in the presence of 12 mmol ammonium hydrogen carbonate/nanofilter.

Biofilm containing fix-bed systems are frequently applied for intensifying biological treatment in wastewater purification. In these operational units a lot of different biofilm carriers have been used and tested; among them, however, the polymer fiber-based materials are barely investigated. The authors studied four carriers: three types of polypropylene (PP) fibers and a polyester (PES) fiber were compared relating their physical–chemical characteristics and biofilm colonization properties. For the physical–chemical characterization surfactants release, wettability, methylene blue bromophenol blue and protein (bovine serum albumin) adsorption were measured as well as the surface charges of the biofilm carriers were determined by zeta potential examinations. Colonization experiments were carried out in a pilot plant scale biological municipal wastewater treatment system consisting of eight cascade reactors for 18 days. Each of the four tested fibers were placed into the reactors, and biofilm colonization was followed by measuring the dry biomass content and TTC (triphenyl tetrazolium chloride) enzyme activity of the biofilms adhered to the polymer fibers. During the colonization experiments pH, chemical oxygen demand (COD), concentration of total suspended solids (TSS), various nitrogenous compounds and dissolved oxygen were also monitored in the water phase of the reactors. Among the four different fibers one of the PP carriers turned to be the most favorable in colonization tests. This carrier, having surface and wetting properties differing from the other ones colonized the maximum biofilm mass, and the biofilm grown on this fiber had also the highest total enzyme activity all along the purification process, both in organic material degrading and in nitrifying reactors.

article i nfo Investigations were performed along the Danube river at Budapest (Hungary) by collecting water and sediment samples simultaneously for 1 year in order to clarify the possible hazard of selected acidic pharmaceuticals (ibuprofen, naproxen, ketoprofen, and diclofenac) on the water supply used for the production of drinking water by bank filtration. In the case of water samples, the sample preparation procedure included solid phase extraction (SPE), meanwhile, in the case of sediment samples, microwave- assisted extraction (MAE) followed by dispersive matrix extraction (DME) for pre-cleaning as well as SPE for enrichment. The quantification was carried out using gas chromatography-mass spectrometry (GC-MS). The calculated recoveries were 97-99% (±7%) for the water and 95-103% (±12%) for the sediment samples. In the river water, ketoprofen concentration was always below the limit of quantification (LOQ) level; ibuprofen, naproxen and diclofenac could be quantified in the range of 8-50, 2-30, 7-90 ng/L. In sediments, only naproxen and diclofenac were found in the range of 2-20 and 5-38 ng/g, respectively. According to the obtained results, the concentration ratios of the two phases linearly depended on the total organic carbon content (TOC) of the sediments at each sampling date. The linear regressions were 0.925 and 0.946 for naproxen and diclofenac, respectively. © 2010 Published by Elsevier B.V.