Showing papers on "Wastewater published in 2001"
TL;DR: A brief summary of input by different sources, occurrence, and elimination of different pharmaceutical groups such as antibiotics, anti-tumour drugs, anaesthetics and contrast media as well as AOX resulting from hospital effluent input into sewage water and surface water will be presented.
1,149 citations
TL;DR: The test period showed that the combined SHARON-Anammox system can work stably over long periods and the process is ready for full-scale implementation.
856 citations
TL;DR: The potential of constructed wetlands for wastewater treatment and reuse in developing countries by looking at the results of current research initiatives towards implementation of the technology in these countries is highlighted in this article.
824 citations
TL;DR: The specific activity of the mesophilic granular sludge was improved under psychrophilic conditions, which indicates that there was growth and enrichment of methanogens and acetogens in the anaerobic system.
492 citations
TL;DR: It is suggested that a suitable quick method of screening a selection of potential media for P-removal potential is to perform simple removal isotherm studies using water with a similar chemical composition as the wastewater to be treated.
419 citations
TL;DR: This paper presents a comprehensive account of the methods/techniques used for the removal of nitrate ion from water during the last 10 years with special reference to the biological denitrification and fate of the metals in decontamination processes.
406 citations
TL;DR: Results indicate that conventional environmental risk assessment overestimates FQ concentrations in surface waters by 1 to 2 orders of magnitude.
Abstract: Fluoroquinolones (FQs) are among the most important antibacterial agents (synthetic antibiotics) used in human and veterinary medicine. An analytical method based on reversed-phase liquid chromatography with fluorescence detection was developed and validated for the simultaneous determination of nine FQs and the quinolone pipemidic acid in urban wastewater. Aqueous samples were extracted using mixed-phase cation-exchange disk cartridges that were subsequently eluted by ammonia solution in methanol. Recoveries were above 80% at an overall precision of better than 10%. Instrumental quantification limits varied between 150 and 450 pg injected. The presented method was successfully applied to quantify FQs in effluents of urban wastewater treatment plants. The two most abundant human-use FQs, ciprofloxacin and norfloxacin, occurred in primary and tertiary wastewater effluents at concentrations between 249 and 405 ng/L and from 45 to 120 ng/L, respectively. The identity of FQs in urban wastewater was confirmed ...
395 citations
TL;DR: This review argues that the information available is insufficient for precise process design and optimization, and simultaneous activated sludge treatment of wastewater and airborne odours could be adopted worldwide.
350 citations
TL;DR: Investigations focussed on the influence of various oxidants like O3, H2O2 and UV light on biodegradation of single components aqueous solution as well as of the whole textile wastewater.
309 citations
TL;DR: In this article, the effect of pH, temperature, initial absorbate concentration, particle size of the adsorbent and solid to liquid ratio on the kinetics of adsorption was delineated.
295 citations
Book•
20 Dec 2001TL;DR: Electrochemical treatment showed to be very efficient in removing colour and chemical oxygen demand and a sensible decrease of chloride and sulphate ions was detected and the technique was proposed for implementation on an industrial scale.
TL;DR: Investigation of in situ bioremediation of polluted soils with diesel fuel with microbiological and chemical analyses and a suitable bioreactor design suggested the best ways to improve biodegradation extents in a diesel-enriched soil.
Abstract: The development of a simple laboratory methodology allows theimplementation of in situbioremediation of polluted soils with diesel fuel. In thisinvestigation microbiological and chemical analyses and a suitable bioreactor design, were veryuseful for suggesting the best ways to improve biodegradation extents in a diesel-enrichedsoil. Biostimulation with inorganic nitrogen and phosphorus produced the best resultsin a simple bioreactor, with biodegradation extents higher than 90% after 45 days. Also,the addition of activated sludge from a domestic wastewater plant increased the degradationrate to a great extent. In both cases, microbiological studies showed the presence ofAcinetobacter sp. degrading most of thehydrocarbons. Simultaneously, a diesel fuel release(approximately 400,000 l) was studied. Samples taken in polluted soil and water revealed thatbacteria from the genus Acinetobacterwere predominant. In plate studies, Acinetobacter coloniesproduced a whitish substance with the characteristics of a biosurfactant. Remarkably, thepresence of this product was evident at the field site, both in the riverbanks and in the physicalrecovery plant. The study of the similarities between laboratory results and the diesel spillsite strongly suggested that natural conditions at the field site allowed the implementationof in situ bioremediation after physical removal of LNAPL (light nonaqueous-phase liquids).
TL;DR: In this article, three common Appalachian plant species (Juncus effusus L, Scirpus validus L., and Typha latifolia L.) were planted into small-scale constructed wetlands receiving primary treated wastewater.
Abstract: Three common Appalachian plant species (Juncus effusus L., Scirpus validus L., and Typha latifolia L.) were planted into small-scale constructed wetlands receiving primary treated wastewater. The experimental design included two wetland gravel depths (45 and 60 cm) and five planting treatments (each species in monoculture, an equal mixture of the three species, and controls without vegetation), with two replicates per depth planting combination. Inflow rates (19 L day 1 ) and frequency (3 times day 1 ) were designed to simulate full-scale constructed wetlands as currently used for domestic wastewater treatment in West Virginia. Influent wastewater and the effluent from each wetland were sampled monthly for ten physical, chemical and biological parameters, and plant demographic measurements were made. After passing through these trough wetlands, the average of all treatments showed a 70% reduction in total suspended solids (TSS) and biochemical oxygen demand (BOD), 50 to 60% reduction in nitrogen (TKN), ammonia and phosphate, and a reduction of fecal coliforms by three orders of magnitude. Depth of gravel (45 or 60 cm) had little effect on wetland treatment ability, but did influence Typha and Scirpus growth patterns. Gravel alone provided significant wastewater treatment, but vegetation further improved many treatment efficiencies. Typha significantly out-performed Juncus and Scirpus both in growth and in effluent quality improvement. There was also some evidence that the species mixture out-performed species monocultures. Typha was the superior competitor in mixtures, but a decline in Typha growth with distance from the influent pipe suggested that nutrients became limiting or toxicities may have developed.
TL;DR: Two new assays studying ammonia oxidation and nitrite oxidation, respectively, are presented, applicable to determination of nitrification inhibition in samples of industrial waste waters or influents of treatment plants, or chemical substances likely to be found in wastewater.
TL;DR: Seventeen olive mill wastewater samples were characterized and the effect of the addition of lime on an artificial phenolic mixture was also examined.
TL;DR: The water balance model (Aquacycle) developed in this study represents water flows through the urban water supply, stormwater, and wastewater systems and was tested using data from the Woden Valley urban catchment in Canberra, Australia and found able to satisfactorily replicate its water supply and wastewater flows.
Abstract: Current urban water management practices aim to remove stormwater and wastewater efficiently from urban areas. An alternative approach is to consider stormwater and wastewater as a potential resource substitute for a portion of the water imported via the reticulated supply system. A holistic view of urban water resources provides the framework for the evaluation of the demand for water supply, the availability of stormwater and wastewater, and the interactions between them. The water balance model (Aquacycle) developed in this study represents water flows through the urban water supply, stormwater, and wastewater systems. Its daily time step provides temporal distribution of the flows, and enables comparison of the different components of the urban water demand. Aquacycle was tested using data from the Woden Valley urban catchment in Canberra, Australia and found able to satisfactorily replicate its water supply, stormwater and wastewater flows. Crown Copyright 2001 Published by Elsevier Science Ltd. All rights reserved.
Book•
04 Jul 2001
TL;DR: In this article, the first and only global synthesis of information related to constructed treatment wetlands is presented, including types of constructed wetlands, major design parameters, role of vegetation, hydraulic patterns, loadings, treatment efficiency, construction, operation and maintenance costs.
Abstract: This book is the first and only global synthesis of information related to constructed treatment wetlands. Types of constructed wetlands, major design parameters, role of vegetation, hydraulic patterns, loadings, treatment efficiency, construction, operation and maintenance costs are discussed in depth. History of the use of constructed wetlands and case studies from various parts of the world are included as well.
TL;DR: The removal of dyes from textile dying wastewater by recycled alum sludge (RAS) generated by the coagulation process itself was studied and optimized and it was found that RAS is a good way of removing hydrophobic dye in wastewater, while simultaneously reducing the fresh alum dosage.
TL;DR: The bagasse fly ash system has been used for the removal of DDD and DDE from the wastewater and the developed system is very useful, economic, and reproducible.
TL;DR: In this paper, the authors evaluated NDMA formation during various water and wastewater treatment processes including chlorination and chloramination, ozonation, and ion exchange, and found that NDMA appears to be a byproduct of the chloramination of water, with the level of NDMA formed directly related to the chloramine dose.
Abstract: N-nitrosodimethylamine (NDMA) is a carcinogen known to be present in various foods and industrial products. The US Environmental Protection Agency has established a 10 -6 cancer risk level for NDMA of 0.7 ng/L. NDMA has been found in the effluents of various water and wastewater plants, but its formation mechanism is not yet understood. This study evaluated NDMA formation during various water and wastewater treatment processes including chlorination and chloramination, ozonation, and ion exchange. On the basis of the limited results obtained in this study, NDMA appears to be a by-product of the chloramination of water and wastewater, with the level of NDMA formed directly related to the chloramine dose. In the waters tested, NDMA did not form on contact with free chlorine or ozone. Contact of one water with typical levels of amine-based polymer did not form any measurable NDMA levels (<2 ng/L). Batch testing was conducted with four strong-base anion exchange resins contacted with untreated groundwater and with buffered deionized water. Results showed that some resins might leach or form NDMA and the level of NDMA produced is a function of the chemical functional group on the surface of the resin.
TL;DR: The experimental results showed that the coagulation-electrooxidation process could efficiently remove the color and the COD from the simulated dye wastewater.
Journal Article•
TL;DR: It is identified that antibiotics of sulfonamides and fluoroquinolones are the most likely water contaminants, followed by macrolides, among sulfonamide and fluoquinolone antibiotics, and sulfamethoxazole and ciprofloxacin are most likely to be present in municipal wastewater effluent and sulf amethazine is most likely in agricultural runoff.
Abstract: Antibiotics are among the emerging microcontaminants in water because of concerns of their potential adverse effects on the ecosystem and possibly on human health. Antibiotics are likely to be released into the aquatic environment via wastewater effluent and agricultural runoff as a result of incomplete metabolism, ineffective treatment removal or improper disposal because large quantities of antibiotics are used annually in human therapy and in agriculture. Despite large quantities of use, published data on the amounts and use patterns of antibiotics are scarce. To assess the magnitude of the potential risks associated with antibiotics, a comprehensive literature review was conducted on the usage, occurrence, and behavior of antibiotics. To identify antibiotics that are likely to be present in water sources, concentrations of antibiotics in municipal wastewater and animal waste in the United States (U.S.) were estimated and were classified according to chemical properties. The estimation of human health antibiotics was based upon the number of prescriptions administered. The estimated concentrations of antibiotics in untreated wastewater range from 3.9 ng/L to approximately 27,000 ng/L. The estimation of animal health antibiotics was based upon the subtherapeutic usage in feed for growth promoting. Considerable variation in antibiotic usage exists among different animal species. Reported data on the occurrence of antibiotics in the aquatic environment confirm the persistence of certain antibiotics. Although information is limited, studies on the transformation and sorption of antibiotics indicate that these processes significantly affect the fate of mo st classes of antibiotics. By combining information on environmental fate with the predicted concentrations, we identify that antibiotics of sulfonamides and fluoroquinolones are the most likely water contaminants, followed by macrolides. Among sulfonamide and fluoroquinolone antibiotics, sulfamethoxazole and ciprofloxacin are most likely to be present in municipal wastewater effluent and sulfamethazine is most likely to be present in agricultural runoff. Azithromycin and tylosin are the most likely macrolides present in municipal wastewater effluent and in agricultural runoff respectively. An occurrence study, which is currently underway, focuses on three of the potential antibiotic contaminants, ciprofloxacin, sulfamethoxazole and sulfamethazine, identified by literature review. Solid phase extraction methods were developed. Recoveries ranged from approximately 45 to 106 percent. Analysis of the three antibiotics was conducted by liquid chromatography mass spectrometry (LC-MS). Additionally, high performance liquid chromatography (HPLC) with fluorescence detection was employed for ciprofloxacin analysis. Preliminary results indicated the presence of ciprofloxacin in secondary wastewater effluent at approximately 80 to 150 ng/L. Sulfamethoxazole was detected in one of the wastewater samples. Sulfamethazine was not detected. Concentrations of antibiotics were found to be much lower or below the detection limits in the effluent of advanced treatment processes including granular activated carbon and ozonation, indicating significant removal by those processes.
TL;DR: It was found that Pseudomonas putida was able to degrade compounds other than phenol, and the bioreactor showed phenol degradation efficiencies higher than 90%, even for a phenol loading rate of 0.5 g phenol/ld (corresponding to 0.54 g TOC/ld).
TL;DR: For each type of sludge examined, there appears to be an optimum level of ECP at which the sludge should exhibit maximum dewaterability, which opens up the possibility of manipulating the level of microbial polymer present to aid sludge dewatering, and hence reduce plant operating costs.
TL;DR: Removal of waste, natural leaching and biological activity, in time, led to an effective decrease in electrical conductivity and phenolic compounds, although residual levels can be important even 2 years later.
TL;DR: All four lysimeters exhibited comparable behavior and there were no significant differences in performance attributable to infiltrative surface character or soil depth, and it is speculated that the comparable performance is due to a similar and sufficient degree of soil clogging genesis coupled with bioprocesses that effectively purified the wastewater effluent given the adequate retention times and high volumetric utilization's of the sand media.
TL;DR: Investigation into the occurrence, character, and transformation of dissolved organic matter (DOM) in treatment wetlands in the western United States shows that the nature of DOM in the source water has a major influence on transformations that occur during treatment.
Abstract: This investigation into the occurrence, character, and transformation of dissolved organic matter (DOM) in treatment wetlands in the western United States shows that (i) the nature of DOM in the source water has a major influence on transformations that occur during treatment, (ii) the climate factors have a secondary effect on transformations, (iii) the wetlands receiving treated wastewater can produce a net increase in DOM, and (iv) the hierarchical analytical approach used in this study can measure the subtle DOM transformations that occur. As wastewater treatment plant effluent passes through treatment wetlands, the DOM undergoes transformation to become more aromatic and oxygenated. Autochthonous sources are contributed to the DOM, the nature of which is governed by the developmental stage of the wetland system as well as vegetation patterns. Concentrations of specific wastewater-derived organic contaminants such as linear alkylbenzene sulfonate, caffeine, and ethylenediaminetetraacetic acid were sig...
TL;DR: An overview of the applications of wet disintegration in wastewater and sludge treatment is provided and thermal, freeze/thaw and biological treatments can be realized at low costs if the conditions are appropriate.
TL;DR: Estimation methods used for determining methane emissions from the management of wastewater, and applications for estimating countrywide methane gas emissions from wastewater management are presented, with Lebanon as an example.