153 research outputs found
Influence of operating parameters on the biodegradation of steroid estrogens and nonylphenolic compounds during biological wastewater treatment processes
This document is the unedited author's version of a Submitted Work that was subsequently accepted for
publication in Environmental Science & Technology, copyright © American Chemical Society after peer
review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/es901612v.This study investigated operational factors influencing the removal of steroid estrogens and nonylphenolic compounds in two sewage treatment works, one a nitrifying/denitrifying activated sludge plant and the other a nitrifying/denitrifying activated sludge plant with phosphorus removal. Removal efficiencies of >90% for steroid estrogens and for longer chain nonylphenol ethoxylates (NP4−12EO) were observed at both works, which had equal sludge ages of 13 days. However, the biological activity in terms of milligrams of estrogen removed per day per tonne of biomass was found to be 50−60% more efficient in the nitrifying/denitrifying activated sludge works compared to the works which additionally incorporated phosphorus removal. A temperature reduction of 6 °C had no impact on the removal of free estrogens, but removal of the conjugated estrone-3-sulfate was reduced by 20%. The apparent biomass sorption (LogKp) values were greater in the nitrifying/denitrifying works than those in the nitrifying/denitrifying works with phosphorus removal for both steroid estrogens and nonylphenolic compounds possibly indicating a different cell surface structure and therefore microbial population. The difference in biological activity (mg tonne−1 d−1) identified in this study, of up to seven times, suggests that there is the potential for enhancing the removal of estrogens and nonylphenols if more detailed knowledge of the factors responsible for these differences can be identified and maximized, thus potentially improving the quality of receiving waters.Public Utilities Board (Singapore), Anglian Water Ltd, Severn Trent Water Ltd, Thames Water Utilities Ltd, United Utilities 393 Plc and Yorkshire Water Services
The fate and behavior of selected endocrine disrupting chemicals in full scale wastewater and sludge treatment unit processes
Endocrine disrupting chemicals are discharged into the environment
mainly through wastewater treatment processes. There is a need for
better understanding of the fate of these compounds in the unit
processes of treatment plant to optimize their removal. The fate of
oestrone, 17β-estradiol, 17α-ethinyestradiol and nonylphenol
in the unit processes of full scale wastewater treatment plants in the
UK, including activated sludge plant, oxidation ditch, biofilter and
rotating biological contractor were investigated. The overall removal
efficiencies of all the compounds ranged from 41 % to 100 %. The
removals were predominantly during the secondary biological treatment
with the rates of removal related to the nitrification rates and the
sludge age. The removal efficiency of the treatment processes were in
the order activated sludge > oxidation ditch > biofilter >
rotating biological contractors. Activated sludge plant configured for
biological nutrient removal showed better removal of the endocrine
disrupting chemicals compared to conventional activated sludge plant
effluents. Tertiary treatment was also significant in the removal
process through solids removal. Overall mechanisms of removal were
biodegradation and sorption unto sludge biomass. Phytoremediation was
also significant in the removal processes. The endocrine disrupting
chemicals persisted in the anaerobic sludge digestion process with
percentage removals ranging fro 10-48 %. Sorption of the endocrine
disrupting chemicals onto the sludge increased with increasing values
for the partitioning coefficients and the organic carbon contents of
the sludge
Unprecedented seismic swarm in the Maurienne valley (2017–2019) observed by the SISmalp Alpine seismic network: operational monitoring and management
Removal and fate of endocrine disruptors chemicals under lab-scalepostreatment stage. Removal assessment using light, oxygen and microalgae
[EN] The aim of this study was to assess the effect of light, oxygen and microalgae on micropollutants removal. The studied micropollutants were 4-(1,1,3,3-tetramethylbutyl)phenol (OP), technical-nonylphenol (t-NP), 4-n-nonylphenol (4-NP), Bisphenol-A (BPA). In order to study the effect of the three variables on the micropollutants removal, a factorial design was developed. The experiments were carried out in four batch reactors which treated the effluent of an anaerobic membrane bioreactor. The gas chromatography mass spectrometry was used for the measurement of the micropollutants. The results showed that light, oxygen and microalgae affected differently to the degradation ratios of each micropollutant. The results showed that under aerated conditions removal ratios higher than 91% were achieved, whereas for non-aerated conditions the removal ratios were between 50% and 80%, except for 4-NP which achieved removal ratios close to 100%. Besides, mass balance showed that the degradation processes were more important than the sorption processes. (C) 2013 Elsevier Ltd. All rights reserved.This research work has been supported by the Spanish Ministry of Economy and Competitiveness (MINECO, Projects CTM2011-28595-C02-01/02) jointly with the European Regional Development Fund (ERDF), The Government of the Region of Valencia (Generalitat Valenciana), within the research project "Application of Water Framework Directive 2000/60/EC on endocrine disruptors and priority substances in coastal areas in the Comunitat Valenciana" and by the Spanish Research Foundation (MINECO, project CTM2008-060809-C02-01/TECNO), within the research project "Feasibility of the SAnMBR technology to treat urban wastewater, and the technical and economic feasibility to industrial implementation" which are gratefully acknowledged.Abargues Llamas, MR.; Ferrer, J.; Bouzas Blanco, A.; Seco Torrecillas, A. (2013). Removal and fate of endocrine disruptors chemicals under lab-scalepostreatment stage. Removal assessment using light, oxygen and microalgae. Bioresource Technology. 149:142-148. https://doi.org/10.1016/j.biortech.2013.09.051S14214814
Remoção de fármacos e desreguladores endócrinos em estações de tratamento de esgoto: revisão da literatura
Population genetics in the homothallic lichen-forming ascomycete Xanthoria parietina
The genetic diversity within and among populations of Xanthoria parietina was studied at the subspecific level with a fingerprinting technique (RAPD-PCR) applied to sterile cultured multispore isolates, each being derived from a single apothecium. Populations from coastal, rural and urban sites from NW, SW and central France and from NE Switzerland were investigated. Between 1 and 8 microsites of a few decimetres square, each comprising 13 to 27 thalli of X. parietina, were analysed per population. A total of 132 isolates from epiphytic and 3 isolates from epilithic specimens were investigated. Phenotypic variation was recorded among some of the thalli in the field and among sterile cultured isolates in the laboratory. A high diversity of genotypes was observed, even among thalli growing side by side in phenotypically homogenous populations. An average of 73·5 % polymorphism was found in all samples. As shown with Principal Coordinates Analysis (PCO), most of the genetic variation (90%) resided within, not among, populations. As X. parietina had previously been shown with molecular and fingerprinting techniques to be homothallic, the potential genetic background of this diversity is discussed. Intense genotype rather than gene (allele) flow seems to be an important element in X. parietina populations
Rôle des polymères hydrosolubles dans l'adhésion de micro-particules minérales à une surface plane : conséquences sur le colmatage de membranes d'ultrafiltration
*INRA, Centre de Versailles Diffusion du document : INRA, Centre de Versailles Diplôme : Dr. d'Universit
A practical approach to OBC summation and geophone calibration in areas of shallow water and hard seafloor.
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