Biodegradation of persistent polar pollutants in wastewater: Comparison of an optimised lab-scale membrane bioreactor and activated sludge treatment

Europa University of Applied Sciences Fresenius, Limburger Strasse 2, D-65510 Idstein, Germany.
Water Research (Impact Factor: 5.53). 11/2006; 40(18):3419-28. DOI: 10.1016/j.watres.2006.07.011
Source: PubMed


The biodegradation of selected non-adsorbing persistent polar pollutants (P(3)) during wastewater (WW) treatment was studied by comparing a lab-scale membrane bioreactor (MBR) running in parallel to activated sludge treatment (AST). The investigated P(3) are relevant representatives or metabolites from the compound classes: pesticides, pharmaceuticals, insect repellents, flame retardants and anionic surfactants. Analyses of all these P(3) at low ng L(-1) levels with sufficient standard deviations was performed in WW influents and effluents. Non-degradable micropollutants, such as EDTA and carbamazepine were not eliminated at all during WW treatment by any technique. However, the MBR showed significant better removals compared to AST for the investigated poorly biodegradable P(3), such as diclofenac, mecoprop and sulfophenylcarboxylates. An application of such an in terms of sludge retention time optimised MBR may lead to a reduction of these P(3) in the watercycle.

Download full-text


Available from: Marco Bernhard,
  • Source
    • "The high variability in the efficiency of secondary treatment reported by other studies (Bernhard et al., 2006; Nakada et al., 2010) also suggests the attenuation of DEET should be dominated by biological rather than physical processes such as adsorption. Indeed, with a log Kow in the range 2.02–2.40 and a Koc in the range 47– 126 L Kg À1 (Weeks et al., 2012), DEET is most likely to remain in the aqueous phase rather than accumulating in solids like activated sludge. "
    [Show abstract] [Hide abstract]
    ABSTRACT: N,N-diethyl-m-toluamide (DEET), the active component of many insect repellents, is among the most frequently detected compounds in aqueous environments with concentrations reported in the ngL(-1) to μgL(-1) range. However, DEET is often detected in blanks and reported concentrations differ significantly depending on the analytical technique employed. In addition, relatively sparse data are available regarding the seasonal variability of DEET concentrations in water and there are apparent inconsistencies with expected use patterns. Therefore, the present study investigates potential interferences affecting the detection and quantification of DEET then the geographical and seasonal variations of DEET concentrations. To examine potential analytical interferences, DEET was analyzed in five geographically-diverse wastewater effluents using both gas chromatography and liquid chromatography coupled to mass spectrometric detectors. At times, the concentrations quantified by the employed analytical methods varied significantly. Five compounds with similar molecular weights and structures as DEET were investigated as potential mimics and some were shown to induce an overestimation of DEET. Further experimentation suggested that the solvents used in sample preparation and HPLC analysis are another possible source of interference. Besides potential interferences, the seven-month weekly monitoring of DEET in the primary effluent of a wastewater treatment plant demonstrated a clear seasonal trend with decreasing concentration from summer to winter. These data collectively demonstrate that there are many challenges in the quantification of DEET in complex environmental samples and that co-occurrence of similarly structured substances present in the water sample and/or the solvents used for the analysis could induce analytical bias. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Chemosphere 03/2015; 127C:238-245. DOI:10.1016/j.chemosphere.2015.02.025 · 3.34 Impact Factor
  • Source
    • "In the presence of NaN 3 the attenuation of TCEP was approximately 25% in both MFCs and MECs (Fig. 3C). TCEP has been reported to be difficult to attenuate in wastewater treatment plants with reports of zero (Meyer and Bester, 2004) to 42% elimination (Bernhard et al., 2006) in activated sludge systems. MFCs and MECs showed higher attenuation of this compound than has been reported for conventional treatment. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) are two types of microbial bioelectrochemical systems (BESs) that use microorganisms to convert chemical energy in wastewaters into useful energy products such as (bio)electricity (MFC) or hydrogen gas (MEC). These two systems were evaluated for their capacity to attenuate trace organic compounds (TOrCs), commonly found in municipal wastewater, under closed circuit (current generation) and open circuit (no current generation) conditions, using acetate as the carbon source. A biocide was used to evaluate attenuation in terms of biotransformation versus sorption. The difference in attenuation observed before and after addition of the biocide represented biotransformation, while attenuation after addition of a biocide primarily indicated sorption. Attenuation of TOrCs was similar in MFCs and MECs for eight different TOrCs, except for caffeine and trimethoprim where slightly higher attenuation was observed in MECs. Electric current generation did not enhance attenuation of the TOrCs except for caffeine, which showed slightly higher attenuation under closed circuit conditions in both MFCs and MECs. Substantial sorption of the TOrCs occurred to the biofilm-covered electrodes, but no consistent trend could be identified regarding the physico-chemical properties of the TOrCs tested and the extent of sorption. The octanol-water distribution coefficient at pH 7.4 (log DpH 7.4) appeared to be a reasonable predictor for sorption of some of the compounds (carbamazepine, atrazine, tris(2-chloroethyl) phosphate and diphenhydramine) but not for others (N,N-Diethyl-meta-toluamide). Atenolol also showed high levels of sorption despite being the most hydrophilic in the suite of compounds studied (log DpH 7.4 = -1.99). Though BESs do not show any inherent advantages over conventional wastewater treatment, with respect to TOrC removal, overall removals in BESs are similar to that reported for conventional wastewater systems, implying the possibility of using BESs for energy production in wastewater treatment without adversely impacting TOrC attenuations. Copyright © 2015. Published by Elsevier Ltd.
    Water Research 01/2015; 73C:56-67. DOI:10.1016/j.watres.2015.01.013 · 5.53 Impact Factor
  • Source
    • "The same metabolite pattern in the radio chromatograms for the two different labeling protocols led to the assumption that the elimination pathway does not involve the removal of the ethinyl group from EE2 molecule. [23] studied the biodegradation of selected non-adsorbing persistent polar pollutants (P3) during wastewater (WW) treatment by comparing a lab-scale membrane bioreactor (MBR) running in parallel to activated sludge treatment (AST). The application of such an MBR optimized in terms of sludge retention time may lead to a reduction of these P3 in the water cycle. "

    Journal of Environmental Protection 01/2015; 06(06):584-598. DOI:10.4236/jep.2015.66053
Show more