Showing papers on "Wastewater published in 2005"
TL;DR: In this article, a review of the recent developments in the synthesis of adsorbents containing polysaccharides, in particular modified biopolymers derived from chitin, chitosan, starch and cyclodextrin, is presented.
1,939 citations
TL;DR: Overall, it can be concluded that for compounds showing a sorption coefficient (K(d) of below 300 L kg(-1), sorption onto secondary sludge is not relevant and their transformation can be assessed simply by comparing influent and effluent concentrations.
828 citations
TL;DR: Results demonstrate that animal wastewaters such as this swine wastewater can be used for power generation in MFCs while at the same time achieving wastewater treatment.
791 citations
TL;DR: Results show that many pharmaceuticals present in wastewater can be efficiently oxidized with O3 and that suspended solids have only a minor influence on the oxidation efficiency of nonsorbing micropollutants.
Abstract: To reduce the release of pharmaceuticals and endocrine disruptors into the aquatic environment or to remove them from wastewater intended for direct or indirect reuse, the application of advanced wastewater treatment may be required. In the present study, municipal wastewater effluents were treated with ozone (O3) in a pilot-scale plant consisting of two bubble columns. The investigated effluents, which varied in suspended solids concentrations, comprised an effluent of conventional activated sludge treatment (CAS), the same effluent dosed with 15 mg of TSS L-1 of activated sludge (CAS + SS), and the effluent of a membrane bioreactor pilot plant (MBR). Selected classes of pharmaceuticals were spiked in the wastewater at realistic levels ranging from 0.5 to 5 μg L-1. Samples taken at the inlet and the outlet of the pilot plant were analyzed with liquid chromatography (LC)−electrospray tandem mass spectrometry (MS). Macrolide and sulfonamide antibiotics, estrogens, and the acidic pharmaceuticals diclofenac,...
784 citations
TL;DR: Investigations lead to the conclusion that low effluent concentrations can be achieved in WWTPs operating SRTs higher than 10 days, which corresponds to the requirements forWWTPs situated in sensitive areas according to the urban wastewater directive of the European Community in moderate climatic zones.
743 citations
TL;DR: This research suggests that selected chemicals are useful as tracers of human wastewater discharge by determining the persistence of a chemically diverse suite of emerging contaminants in streams.
Abstract: The quality of drinking and recreational water is currently (2005) determined using indicator bacteria. However, the culture tests used to analyze forthese bacteria require a long time to complete and do not discriminate between human and animal fecal material sources. One complementary approach is to use chemicals found in human wastewater, which would have the advantages of (1) potentially shorter analysis times than the bacterial culture tests and (2) being selected for human-source specificity. At 10 locations, water samples were collected upstream and at two successive points downstream from a wastewaster treatment plant (WWTP); a treated effluent sample was also collected at each WWTP. This sampling plan was used to determine the persistence of a chemically diverse suite of emerging contaminants in streams. Samples were also collected at two reference locations assumed to have minimal human impacts. Of the 110 chemical analytes investigated in this project, 78 were detected at least once. The number of compounds in a given sample ranged from 3 at a reference location to 50 in a WWTP effluent sample. The total analyte load at each location varied from 0.018 microg/L at the reference location to 97.7 microg/L in a separate WWTP effluent sample. Although most of the compound concentrations were in the range of 0.01-1.0 microg/L, in some samples, individual concentrations were in the range of 5-38 microg/L. The concentrations of the majority of the chemicals present in the samples generally followed the expected trend: they were either nonexistent or at trace levels in the upstream samples, had their maximum concentrations in the WWTP effluent samples, and then declined in the two downstream samples. This research suggests that selected chemicals are useful as tracers of human wastewater discharge.
670 citations
TL;DR: It is demonstrated here that hydrogen production from a food processing wastewater high in sugar can be linked to electricity generation using a microbial fuel cell (MFC) to achieve more effective wastewater treatment and bioenergy production.
586 citations
TL;DR: The vertical flow constructed wetland system is an attractive alternative to the common practice of soil infiltration and provides efficient treatment of domestic sewage for discharge into the aquatic environment as mentioned in this paper, but it is not suitable for outdoor applications.
428 citations
01 Jul 2005
TL;DR: Coal, residual coal, and residual coal treated with H3PO4 as a means of removal of phenol from wastewater is investigated and the results showed that the equilibrium data for all the phenol-sorbent systems fitted the Redlich-Peterson model best.
Abstract: The present work involves an investigation of the possible use of coal, residual coal, and residual coal treated with H3PO4 as a means of removal of phenol from wastewater. The study was realized using batch experiments, with synthetic wastewater having phenol concentration of 1000 ppm. Other low-cost adsorbents such as petroleum coke, coke breeze, rice husk, and rice husk char have also been used. The effect of system variables such as pH, contact time, and temperature has been investigated. The suitability of the Freundlich, Langmuir, and Redlich-Peterson adsorption models to the equilibrium data was investigated for each phenol-adsorbent system. The results showed that the equilibrium data for all the phenol-sorbent systems fitted the Redlich-Peterson model best. Kinetic modeling of removal of phenols was done using the Lagergren first-order rate expression. A series of column experiments were performed to determine the breakthrough curves.
422 citations
TL;DR: In this paper, the food processing industry produces highly concentrated, carbohydrate-rich wastewaters, but their potential for biological hydrogen production has not been extensively studied, and there is no evidence that hydrogen production is correlated with chemical oxygen demand removal.
TL;DR: The results showed that 29% of the carbamazepine was removed from the aqueous phase during treatment in the WWTP, while the metabolites were not effectively removed, which appeared to be due primarily to degradation.
Abstract: Pharmaceutically active compounds (PhACs) are discharged into the environment from domestic wastewater treatment plants (WWTPs). In this study, we determined the distribution of the anti-epileptic drug, carbamazepine (CBZ), and its major metabolites and caffeine in both aqueous and solid phases through different treatment processes of a WWTP. A method was developed to extract samples of biosolids using pressurized liquid extraction (PLE), coupled with cleanup of extracts using solid-phase extraction. Samples of biosolids and wastewater were analyzed for caffeine and CBZ and five of its metabolites, 10,11-dihydro-10,11-epoxycarbamazepine (CBZ-EP), 11-dihydro-10,11-epoxycarbamazepine (CBZ-DiOH), 2-hydroxycarbamazepine (CBZ-20H), 3-hydroxycarbamazepine (CBZ-30H), and 10,11-dihydro-10-hydroxycarbamazepine (CBZ-100H). The analytes were quantified using liquid chromatography-electrospray ionization tandem mass spectrometry. The recoveries of the analytes were 82.1-91.3% from raw biosolids and 80.1-92.4% from treated biosolids, and the limits of detection were 0.06-0.50 and 0.06-0.40 microg/kg on a wet weight basis for raw and treated biosolids, respectively. The behavior of carbamazepine and its metabolites, together with caffeine as a marker of domestic inputs, was investigated in the WWTP for the City of Peterborough, ON, Canada, which utilizes secondary sewage treatment technologies. CBZ, CBZ-2OH, CBZ-30H, and CBZ-DiOH were detected at concentrations of 69.6, 1.9, 1.6, and 7.5 microg/kg (dry weight), respectively, in untreated biosolids and at concentrations of 258.1, 3.4, 4.3, and 15.4 microg/kg (dry weight), respectively, in treated biosolids. However, CBZ-EP and CBZ-100H were not detected in any of the biosolid samples. CBZ and its five metabolites were detected in all wastewater samples collected from four different stages of treatment. The results showed that 29% of the carbamazepine was removed from the aqueous phase during treatment in the WWTP, while the metabolites were not effectively removed. Concentrations of caffeine were reduced by 99.9% in the aqueous phase, which appeared to be due primarily to degradation. Caffeine was also detected at concentrations of 165.8 and 7.6 microg/kg (dry weight) in raw and treated biosolids, respectively. Because of differences in hydrophobicity, CBZ is the primary analyte in biosolids, while CBZ-DiOH is the primary analyte in the aqueous phase of the wastewater. A mass balance calculation showed that the majority of CBZ and its metabolites exist in the aqueous phase (i.e., wastewater), ratherthan in the biosolids, 78 g of CBZ and its metabolites enters the Peterborough WWTP daily, and 91 g is discharged from the WWTP daily in the combined suspended solids and aqueous phases of the wastewater. The calculated daily inputs into the WWTP are somewhat less than the inputs of 192 g estimated from Canadian annual sales data for CBZ.
TL;DR: Mefenamic acid seems to present a risk for the aquatic environment, with a ratio PEC/PNEC higher than one, and Ibuprofen was well removed by one sewage treatment plant, showing a potential contamination of surface water.
TL;DR: In this paper, a blue reactive dye (Drimarene K2LR CDG Blue) solution was optimized by experimental design and surface response analysis in terms of colour removal and chemical oxygen demand (COD) decrease.
Abstract: Electro-coagulation of a blue reactive dye (Drimarene K2LR CDG Blue) solution has been optimised by experimental design and surface response analysis in terms of colour removal and chemical oxygen demand (COD) decrease. The optimal conditions (pH, current density, reaction time) have then been applied to other reactive dyes solutions as well as synthetic and real textile wastewater samples. The biodegradability before and after electro-coagulation has been assessed by short-term respirometry and is increased by this type of treatment.
TL;DR: The presence of human pharmaceutical compounds in surface waters is an emerging issue in environmental science and the high cost involved suggests that more attention should be given to the potential for the optimization of current treatment processes, and reduction at source in order to reduce environmental contamination.
Abstract: The presence of human pharmaceutical compounds in surface waters is an emerging issue in environmental science. In this study the occurrence and behavior of human pharmaceuticals in a variety of wastewater treatment processes is reviewed. Although some groups are not affected by sewage treatment processes others are amenable to degradation, albeit incomplete. While water purification techniques such as granular activated carbon could potentially remove these pollutants from wastewater streams, the high cost involved suggests that more attention should be given to the potential for the optimization of current treatment processes, and reduction at source in order to reduce environmental contamination.
TL;DR: Modifications were introduced into the original WQI to reduce the costs associated with its implementation, and WQIDIR2 and WZIDIR, which are both based on a laboratory analysis and three field measurements, adequately reproduce the most important spatial and temporal variations observed with the original index are proposed.
Abstract: The Chillan River in Central Chile plays a fundamental role in local society, as a source of irrigation and drinking water, and as a sink for urban wastewater. In order to characterize the spatial and temporal variability of surface water quality in the watershed, a Water Quality Index (WQI) was calculated from nine physicochemical parameters, periodically measured at 18 sampling sites (January-November 2000). The results indicated a good water quality in the upper and middle parts of the watershed. Downstream of the City of Chillan, water quality conditions were critical during the dry season, mainly due to the effects of the urban wastewater discharge. On the basis of the results from a Principal Component Analysis (PCA), modifications were introduced into the original WQI to reduce the costs associated with its implementation. WQIDIR2 and WQIDIR, which are both based on a laboratory analysis (Chemical Oxygen Demand) and three (pH, temperature and conductivity), respectively, four field measurements (pH, temperature, conductivity and Dissolved Oxygen), adequately reproduce the most important spatial and temporal variations observed with the original index. They are proposed as useful tools for monitoring global water quality trends in this and other, similar agricultural watersheds in the Chilean Central Valley. Possibilities and limitations for the application of the used methodology to watersheds in other parts of the world are discussed.
TL;DR: In this paper, the performance of mesophilic anaerobic digesters of four large Italian wastewater treatment plants without primary sedimentation was studied, and a mathematical model for the prediction of biogas production on the solid retention time applied in the wastewater treatment process was developed.
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01 Jan 2005
TL;DR: Water Quality and Wastewater Treatment Basic principles of Wastewater treatment Natural Treatment Systems Anaerobic Reactors Activated Sludge Sludge Treatment and Disposal Water Quality and Water Quality:
Abstract: Introduction to Water Quality and to Wastewater Treatment Basic Principles of Wastewater Treatment Natural Treatment Systems Anaerobic Reactors Activated Sludge Sludge Treatment and Disposal
TL;DR: An overview of the status of membrane processes in wastewater reclamation and reuse world-wide and depict their potential role in promoting more sustainable water use patterns is provided in this paper, where two types of systems have been built, a centralised type of treatment with dual membrane processes, including microfiltration (MF) and reverse osmosis (RO), and small scale systems using membrane bioreactors.
TL;DR: In this paper, an innovative system that combines three different membrane processes for reclamation and reuse of wastewater in future space missions was evaluated, and the conditions for minimum energy consumption were determined and used in estimating the specific energy cost of treating the wastewater generated in space.
TL;DR: This paper analyzes greenhouse gas emissions from both aerobic and anaerobic treatment systems, including sludge digestion and the losses of dissolved methane in digested biosolids and process effluents.
TL;DR: In vitro experiments demonstrated that the virus could only persist for 2 days in hospital wastewater, domestic sewage and dechlorinated tap water, while 3 days in feces, 14 days in PBS and 17 days in urine at 20°C; however, at 4°C, the SARS-CoV could persist for 14 Days in wastewater and at least 17 Days in feces or urine.
TL;DR: In this paper, a dual membrane contactor process for treatment of combined hygiene and metabolic wastewater was investigated and it was demonstrated that water flux could be increased by up to 25 times with only a 3-5 C temperature difference across the membranes.
TL;DR: In this article, the ability of submerged MBRs to remove pharmaceutically active compounds (PhACs) was examined at an existing municipal wastewater treatment facility, and the performance of the MBRs was compared with that of the conventional activated sludge (CAS) process.
TL;DR: The first experiments using wetland macrophytes for wastewater treatment were carried out in Germany in the early 1950s and since then, the constructed wetlands have evolved into a reliable wastewater treatment technology for various types of wastewater.
TL;DR: In this paper, a combined electrocoagulation and electroflotation process was designed to reduce Cr 6+ to Cr 3+ first and then to remove the total Cr from wastewater to a value below 0.5
TL;DR: In this article, the authors compared six wastewater sludge treatment scenarios applied to a 300,000 equivalent-inhabitant (eq. inh) wastewater treatment plant: agricultural spreading, fluidised bed incineration, wet oxidation, pyrolysis, incineration in cement kilns and landfill.
TL;DR: The generation of electricity during wastewater treatment may profoundly affect the approach to anaerobic treatment technologies used in wastewater treatment, and progress is being made that may result in as much as 0.5 MW from wastewater treatment.
TL;DR: The steps of an ecological risk assessment and management framework related to hospital effluents evacuating into wastewater treatment plant (WWTP) without preliminary treatment are presented and the results of its application on wastewater from an infectious and tropical diseases department of a hospital of a large city in southeastern France are presented.
TL;DR: In this paper, the effects of acetate and different salts present in the feeding of a SHARON reactor have been evaluated, and it was shown that concentrations up to 0.2 g TOC/L did not exert significant effect on the ammonia oxidation to nitrite.