Water and soil contamination by industrial wastes is a global concern. Biological treatment of industrial wastewater using bioreactors allows the removal of organic matter and nutrients and enables either reuse or safe discharge. Wastewater bioremediation depends in part on the microbial communities present in the bioreactor.
View Article and Find Full Text PDFBackground And Aims: Wastewater-based epidemiology is an additional indicator of drug use that is gaining reliability to complement the current established panel of indicators. The aims of this study were to: (i) assess spatial and temporal trends of population-normalized mass loads of benzoylecgonine, amphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) in raw wastewater over 7 years (2011-17); (ii) address overall drug use by estimating the average number of combined doses consumed per day in each city; and (iii) compare these with existing prevalence and seizure data.
Design: Analysis of daily raw wastewater composite samples collected over 1 week per year from 2011 to 2017.
Bacteriophages are viruses that infect bacteria, and consequently they have a major impact on the development of a microbial population. In this study, the genome of a novel broad host range bacteriophage, phage P14, isolated from a wastewater treatment plant, was analyzed. The phage P14 was found to infect members of different Proteobacteria classes (Alphaproteobacteria and Betaproteobacteria).
View Article and Find Full Text PDFThis study focuses on the stability and tolerance of continuous-flow bioreactors inoculated with anaerobic methanogens in three different configurations: (R1) dried granular biomass immobilized in PAC-enriched hydrophilic polyurethane foam, (R2) dried granular biomass, and (R3) wet granular biomass. These systems were tested under two different organic loading rates (OLR) of 6.25 and 10.
View Article and Find Full Text PDFThe main goal of this study was to test the effect of various drying methods of granular anaerobic biomass on biomass survival, potential and rate of methane re-production, and structure. This may facilitate the development of drying methods to preserve excess anaerobic biomass in dry form for re-inoculation of existing digesters after process failure or wash out or for the start-up of new digesters. To that end, anaerobic granular biomass was collected from an up-flow anaerobic sludge blanket (UASB) reactor.
View Article and Find Full Text PDFThe overall aim of the this study, which was conducted within the framework of the multilateral IWRM project SUMAR, was to expand the scientific basement to quantify surface- and groundwater fluxes towards the hypersaline Dead Sea. The flux significance for the arid vicinity around the Dead Sea is decisive not only for a sustainable management in terms of water availability for future generations but also for the resilience of the unique ecosystems along its coast. Coping with different challenges interdisciplinary methods like (i) hydrogeochemical fingerprinting, (ii) satellite and airborne-based thermal remote sensing, (iii) direct measurement with gauging station in ephemeral wadis and a first multilateral gauging station at the river Jordan, (iv) hydro-bio-geochemical approach at submarine and shore springs along the Dead Sea and (v) hydro(geo)logical modelling contributed to the overall aim.
View Article and Find Full Text PDFThree pilot-scale duckweed pond (DP) wastewater treatment systems were designed and operated to examine the effect of aeration and effluent recycling on treatment efficiency. Each system consisted of two DPs in series fed by pre-settled domestic sewage. The first system (duckweed+ conventional treatment) was 'natural' and included only duckweed plants.
View Article and Find Full Text PDFMicroorganisms are retained by ultrafiltration (UF) membranes mainly due to size exclusion. The sizes of viruses and membrane pores are close to each other and retention of viruses can be guaranteed only if the precise pore diameter is known. Unfortunately and rather surprisingly, there is no direct method to determine the membrane pore size.
View Article and Find Full Text PDFThe fates of several macrolide, sulphonamide, and trimethoprim antibiotics contained in the raw sewage of the Tel-Aviv wastewater treatment plant (WWTP) were investigated after the sewage was treated using either a full-scale conventional activated sludge (CAS) system coupled with a subsequent ultrafiltration (UF) step or a pilot membrane bioreactor (MBR) system. Antibiotics removal in the MBR system, once it achieved stable operation, was 15-42% higher than that of the CAS system. This advantage was reduced to a maximum of 20% when a UF was added to the CAS.
View Article and Find Full Text PDFAn economic analysis and feasibility study of a sequential biosolids management process was developed and tested using Genetic Algorithm (GA). The algorithm was used to identify trends and behaviors of the "Biosolids Process Train". This heuristic method of analysis is robust in that it will not only simulate different design scenarios, its analysis will also suggest possible solutions which meet predetermined requirements.
View Article and Find Full Text PDFProduction of biodiesel is currently limited due to lack of economically beneficial feedstocks. Suitability of municipal wastewater sludge and olive mill waste as feedstocks for biodiesel production was evaluated. The various bio-waste sources were analyzed for their oil content and fatty acid composition using conventional analyses complemented with time domain (TD)-NMR analysis.
View Article and Find Full Text PDFChanges in the microbial community composition of a full-scale membrane bioreactor treating industrial wastewater were studied over a period of 462 days using a series of 16S rRNA gene clone libraries. Frequent changes in the relative abundance of specific taxonomic groups were observed, which could not be explained by changes in the reactor's conditions or wastewater composition. Phage activity was proposed to drive some of the observed changes.
View Article and Find Full Text PDFInt J Environ Res Public Health
February 2009
Flame-retardants (FR) are a group of anthropogenic environmental contaminants used at relatively high concentrations in many applications. Currently, the largest market group of FRs is the brominated flame retardants (BFRs). Many of the BFRs are considered toxic, persistent and bioaccumulative.
View Article and Find Full Text PDFAbundance and seasonal dynamics of sulfate-reducing bacteria (SRB), in general, and of extreme halophilic SRB (belonging to Desulfocella halophila) in particular, were examined in highly saline industrial wastewater evaporation ponds over a forty one month period. Industrial wastewater was sampled and the presence of SRB was determined by quantitative real-time PCR (qPCR) with a set of primers designed to amplify the dissimilatory sulfite reductase (dsrA) gene. SRB displayed higher abundance during the summer (10(6)-10(8) targets ml(-1)) and lower abundance from the autumn-spring (10(3)-10(5) targets ml(-1)).
View Article and Find Full Text PDFHalogenated organic compounds constitute one of the largest and most diverse groups of chemicals in the environment. Many of these compounds are toxic, persistent and, as a result of their often limited biodegradability, tend to bioaccumulate in the environment. Dibromoneopentyl glycol (DBNPG) and tribromoneopentyl alcohol (TBNPA) are brominated flame retardants commonly used as additives during the manufacture of plastic polymers and as chemical intermediates in the synthesis of other flame retardants.
View Article and Find Full Text PDFThe filtration of phi X 174, MS2, and T4 bacteriophages out of tap water and secondary effluents was performed by rapid sand filtration. The viruses were characterized, and the influence of their microscopic characteristics on filterability was examined by comparing retention values, residence times, attachment, and dispersion coefficients calculated from an advection-dispersion model and residence time variation. The only factor observed to influence retention was virus size, such that the larger the virus, the better the retention.
View Article and Find Full Text PDFThe salinity of industrial wastewater evaporation ponds was artificially increased from 3-7% to 12-16% (w/v), in an attempt to reduce the activity of sulfate-reducing bacteria (SRB) and subsequent emission of H2S. To investigate the changes in bacterial diversity in general, and SRB in particular, following this salination, two sets of universal primers targeting the 16S rRNA gene and the functional apsA [adenosine-5'-phosphosulfate (APS) reductase alpha-subunit] gene of SRB were used. Phylogenetic analysis indicated that Proteobacteria was the most dominant phylum both before and after salination (with 52% and 68%, respectively), whereas Firmicutes was the second most dominant phylum before (39%) and after (19%) salination.
View Article and Find Full Text PDFReal-time polymerase chain reaction (PCR) is considered a highly sensitive method for the quantification of microbial organisms in environmental samples. This study was conducted to evaluate real-time PCR with SybrGreen detection as a quantification method for sulfate-reducing bacteria (SRB) in industrial wastewater produced by several chemical industries. We designed four sets of primers and developed standard curves based on genomic DNA of Desulfovibrio vulgaris from pure culture and on plasmids containing dissimilatory sulfate reductase (dsrA) or adenosine-5'-phosphosulfate reductase (apsA) genes of SRB.
View Article and Find Full Text PDFThe wastewater of the largest dairy factory in Israel (Tnuva, Tel-Yosef), discharging approximately 6000 tons BOD per year, is treated in two serial, deep reservoirs (anaerobic/facultative). In this study, which focused on the anaerobic reservoir, we combined in situ measurements (over 18 months) and supporting lab experiments, in order to evaluate its efficiency and to identify the rate-limiting step of the methanogenic fermentation pathway. The anaerobic reservoir could remove above 75% of the BOD and COD all year round, but this was not enough to prevent malodors during the winter.
View Article and Find Full Text PDFLaboratory reactor systems based on the conventional (aerobic) activated sludge process and on the contact (anaerobic) process were operated almost one year in order to develop a biological process for the degradation of the fire retardant tetrabromobisphenol A (TBBPA) and to find out if its degradation might result in the formation of the endocrine disruptor bisphenol A (BPA). The reactors were fed a TBBPA waste mixture containing also tribromophenol (TBP), and added with contaminated sediments that might have contained indigenous bacteria exposed to these compounds. Various organic compounds were used as potential electron donors to enhance growth of halorespiring bacteria that would debrominate the TBBPA and make it available for further aerobic mineralization.
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