Download or read book Evaluation of N Nitrosodimethylamine NDMA Formation at Varied PH and Conditions in Treated Wastewater written by Chetna Vasudeva and published by . This book was released on 2018 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: N-nitrosodimethylamine is a carcinogenic disinfection byproduct which can be reformed after wastewater treatment if appropriate conditions are present. In this study various NDMA formation precursors over a range of conditions have been studied to attempt to quantify this NDMA reformation potential. Efforts were made in this study to demonstrate the effect of time, pH, and multiple different precursor chemicals on the reformation process. Dimethylamine (DMA) has been demonstrated to be a precursor chemical, and was chosen as a standard for initial experiments. The concentration of this precursor was kept constant at 100 ppt (parts per trillion) and solutions at three different pH’s were tested over a 24-hour time period to see if any significant NDMA formation occurred. The impacts of various treated wastewater constituent chemicals including H2O2, monochloramine, dimethylhydrazine, etc. were also performed in this study. Significant difficulties occurred for the analysis of these samples, with large background interferences occurring in the method of analysis. Based on the data obtained, it appears that the formation potential of NDMA with DMA as a precursor was found to be the most efficient compound at basic pH (pH 9) and very basic (pH 13). This is consistent with the last step in wastewater remediation, where quicklime is added to the water to regulate the pH and for protection of distribution system. In addition, preliminary experiments were conducted using Ranitidine as a NDMA reformation precursor.
Download or read book Stability Formation Potential and Removal of N nitrosodimethylamine NDMA in Drinking Water written by Xiaoyan Qin and published by . This book was released on 2005 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: NDMA stability under various water treatment conditions were tested under both laboratory and field conditions. NDMA concentrations were determined in the laboratory by varying temperature, alkalinity, TOC, pH, free chlorine and monochloramine. The results indicated no NDMA degradation occurred while varying these parameters, except for monochloramine, where NDMA increased when treated with monochloramine. Field work included monitoring four utilities quarterly for a year. Seasonal variation and the stability of NDMA in the distribution systems were studied. Unfortunately, the NDMA formation level was low and no trend could be determined. The use of UV for the destruction of NDMA was evaluated. NDMA degradation by UV was a pseudo-first order reaction. NDMA was reduced from 100 ng/L to 10 ng/L with 1000 mJ/cm 2 UV dosage. The results confirmed that UV is a feasible technique for NDMA removal. pH did not have any significant effects. A total of sixty Missouri lake water samples were treated with 1 mM monochloramine for 2 days and 7 days to evaluate NDMA formation potential. NDMA was formed in almost all lake samples, the differences of the formation level and rate may indicate the existence of different NDMA precursors in these lakes. There was a positive correlation between NDMA formation and DOC concentration.
Download or read book A Study of the Effect of Polymers on Potential N Nitrosodimethylamine NDMA Formation at Water and Wastewater Treatment Plants written by and published by . This book was released on 2007 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Potential N Nitrosodimethylamine NDMA Formation from Water Treatment Polymers written by Piti Piyachaturawat and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: N-Nitrosodimethylamine (commonly known as NDMA) is a probable human carcinogen that has been recognized as an emerging drinking water contaminant in recent years. Previous studies have shown that certain N-containing organic compounds may form NDMA in reaction with chlorine or monochloramine and the NDMA yield is affected by the structure of the organic-N compounds, water conditions and treatment parameters. Many amine-based water treatment polymers contain organic-N functional groups and thus have been suspected as potential NDMA precursors in water treatment systems. The purpose of this research was to systematically assess the potential NDMA formation from different structural types of water treatment polymers in reactions with various oxidants and probe the possible factors that influence the NDMA formation. Robust analytical methods for detection of NDMA and the well-known NDMA precursor dimethylamine (DMA) in the reaction samples were established. The cationic polyacrylamide (cationic PAMS), aminomethylated polyacrylamide (Mannich), poly-diallyldimethylammonium chloride (polyDADMAC) and polyamine polymers were evaluated in reactions with nitrite, free chlorine, monochloramine or chlorine dioxide in aqueous solutions at circumneutral pH and room temperature conditions. This study employed high dosages of polymer and oxidant and long reaction time in order to assess the maximum potential to form NDMA. A range of operational parameters that may affect the above reactions were also evaluated.
Download or read book Prevention of the Formation of N nitrosodimethylamine NDMA During Wastewater Chlorination written by William Armistead Mitch and published by . This book was released on 2003 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study on the Effect of Polymers on Potential N nitrosodimethylamine NDMA Formation at Water and Wastewater Treatment Plants written by and published by . This book was released on 2007 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigations Into the Occurrence Formation and Fate of N nitrosodimethylamine NDMA in Air and Water written by Jinwei Zhang and published by . This book was released on 2016 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: N-nitrosodimethylamine (NDMA), a probable human carcinogen, has been found in clouds and fogs at concentration up to 500 ng/L and in drinking water as a disinfection by-product. NDMA exposure to the general public is not well understood because of knowledge gaps in terms of occurrence, formation and fate - both in air and water. The goal of this dissertation was to contribute to closing these knowledge gaps on potential human NDMA exposure through contributions to atmospheric measurements and fate as well as aqueous formation processes. Novel, sensitive methods of measuring NDMA in air were developed based on Solid Phase Extraction (SPE) and Solid Phase Microextraction (SPME) coupled to Gas Chromatography-Mass Spectrometry (GC-MS). The two measuring techniques were evaluated in laboratory experiments. SPE-GC-MS was applicable in ambient air sampling and NDMA in ambient air was found in the 0.1-13.0 ng/m3 range. NDMA photolysis, the main degradation atmospheric pathway, was studied in the atmospheric aqueous phase. Water soluble organic carbon (WSOC) was found to have more impact than inorganic species on NDMA photolysis by competing with NDMA for photons and therefore could substantially increase the NDMA lifetime in the atmosphere. The optical properties of atmospheric WSOC were investigated in aerosol, fog and cloud samples and showed WSOC from atmospheric aerosols has a higher mass absorption efficiency (MAE) than organic matter in fog and cloud water, resulting from a different composition, especially in regards to volatile species, that are not very absorbing but abundant in fogs and clouds. NDMA formation kinetics during chloramination were studied in aqueous samples including wastewater, surface water and ground water, at two monochloramine concentrations. A simple second order NDMA formation model was developed using measured NDMA and monochloramine concentrations at select reaction times. The model fitted the NDMA formation well (R2 >0.88) in all water matrices. The proposed model was then optimized and applied to fit the data of NDMA formation from natural organic matter (NOM) and model precursors in previously studies. By determining the rate constants, the model was able to describe the effect of water conditions such as DOC and pH on NDMA formation.
Download or read book The Llobregat written by Sergi Sabater and published by Springer. This book was released on 2012-06-02 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Llobregat belongs to the most thoroughly studied rivers in Europe and is a paradigm of the confluence of human and natural disturbances in a single basin. Because of its location in a very densely populated region and its Mediterranean character, the Llobregat supports a mixture of irregular flow, water abstraction, excess nutrients, mining debris, and a wide array of pollutants. The aquatic organisms strive to survive in a dramatically changing river that passes through a succession of dams, weirs and channels. The long-term river monitoring as well as the research that has been carried out in the river for a long time have provided an extensive knowledge of these disturbances and their effects on the biological communities. This book highlights the available information, with emphasis on the hydrological, chemical and biological elements interspersed in the river. Experts in the field discuss the main nutrient patterns and pollutant occurrence and the responses of the biological quality elements as well as the river ecosystem to the overall natural and man-made influences.
Download or read book Toxicological Profile for N nitrosodimethylamine written by and published by . This book was released on 1989 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water Reuse written by National Research Council and published by National Academies Press. This book was released on 2012-07-17 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Expanding water reuse-the use of treated wastewater for beneficial purposes including irrigation, industrial uses, and drinking water augmentation-could significantly increase the nation's total available water resources. Water Reuse presents a portfolio of treatment options available to mitigate water quality issues in reclaimed water along with new analysis suggesting that the risk of exposure to certain microbial and chemical contaminants from drinking reclaimed water does not appear to be any higher than the risk experienced in at least some current drinking water treatment systems, and may be orders of magnitude lower. This report recommends adjustments to the federal regulatory framework that could enhance public health protection for both planned and unplanned (or de facto) reuse and increase public confidence in water reuse.
Download or read book Advanced Oxidation Processes for Water Treatment written by Mihaela I. Stefan and published by IWA Publishing. This book was released on 2017-09-15 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Oxidation Processes (AOPs) rely on the efficient generation of reactive radical species and are increasingly attractive options for water remediation from a wide variety of organic micropollutants of human health and/or environmental concern. Advanced Oxidation Processes for Water Treatment covers the key advanced oxidation processes developed for chemical contaminant destruction in polluted water sources, some of which have been implemented successfully at water treatment plants around the world. The book is structured in two sections; the first part is dedicated to the most relevant AOPs, whereas the topics covered in the second section include the photochemistry of chemical contaminants in the aquatic environment, advanced water treatment for water reuse, implementation of advanced treatment processes for drinking water production at a state-of-the art water treatment plant in Europe, advanced treatment of municipal and industrial wastewater, and green technologies for water remediation. The advanced oxidation processes discussed in the book cover the following aspects: - Process principles including the most recent scientific findings and interpretation. - Classes of compounds suitable to AOP treatment and examples of reaction mechanisms. - Chemical and photochemical degradation kinetics and modelling. - Water quality impact on process performance and practical considerations on process parameter selection criteria. - Process limitations and byproduct formation and strategies to mitigate any potential adverse effects on the treated water quality. - AOP equipment design and economics considerations. - Research studies and outcomes. - Case studies relevant to process implementation to water treatment. - Commercial applications. - Future research needs. Advanced Oxidation Processes for Water Treatment presents the most recent scientific and technological achievements in process understanding and implementation, and addresses to anyone interested in water remediation, including water industry professionals, consulting engineers, regulators, academics, students. Editor: Mihaela I. Stefan - Trojan Technologies - Canada
Download or read book Advanced Oxidation Processes for Water and Wastewater Treatment written by Simon Parsons and published by IWA Publishing. This book was released on 2004-03-01 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: The suitability of Advanced Oxidation Processes (AOPs) for pollutant degradation was recognised in the early 1970s and much research and development work has been undertaken to commercialise some of these processes. AOPs have shown great potential in treating pollutants at both low and high concentrations and have found applications as diverse as ground water treatment, municipal wastewater sludge destruction and VOCs control. Advanced Oxidation Processes for Water and Wastewater Treatment is an overview of the advanced oxidation processes currently used or proposed for the remediation of water, wastewater, odours and sludge. The book contains two opening chapters which present introductions to advanced oxidation processes and a background to UV photolysis, seven chapters focusing on individual advanced oxidation processes and, finally, three chapters concentrating on selected applications of advanced oxidation processes. Advanced Oxidation Processes for Water and Wastewater Treatment will be invaluable to readers interested in water and wastewater treatment processes, including professionals and suppliers, as well as students and academics studying in this area. Dr Simon Parsons is a Senior Lecturer in Water Sciences at Cranfield University with ten years' experience of industrial and academic research and development.
Download or read book Advanced Oxidation Processes written by Ciro Bustillo-Lecompte and published by BoD – Books on Demand. This book was released on 2020-06-10 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Oxidation Processes – Applications, Trends, and Prospects constitutes a comprehensive resource for civil, chemical, and environmental engineers researching in the field of water and wastewater treatment. The book covers the fundamentals, applications, and future work in Advanced Oxidation Processes (AOPs) as an attractive alternative and a complementary treatment option to conventional methods. This book also presents state-of-the-art research on AOPs and heterogeneous catalysis while covering recent progress and trends, including the application of AOPs at the laboratory, pilot, or industrial scale, the combination of AOPs with other technologies, hybrid processes, process intensification, reactor design, scale-up, and optimization. The book is divided into four sections: Introduction to Advanced Oxidation Processes, General Concepts of Heterogeneous Catalysis, Fenton and Ferrate in Wastewater Treatment, and Industrial Applications, Trends, and Prospects.
Download or read book Chemistry of Ozone in Water and Wastewater Treatment written by Clemens von Sonntag and published by IWA Publishing. This book was released on 2012-08-31 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Even though ozone has been applied for a long time for disinfection and oxidation in water treatment, there is lack of critical information related to transformation of organic compounds. This has become more important in recent years, because there is considerable concern about the formation of potentially harmful degradation products as well as oxidation products from the reaction with the matrix components. In recent years, a wealth of information on the products that are formed has accumulated, and substantial progress in understanding mechanistic details of ozone reactions in aqueous solution has been made. Based on the latter, this may allow us to predict the products of as yet not studied systems and assist in evaluating toxic potentials in case certain classes are known to show such effects. Keeping this in mind, Chemistry of Ozone in Water and Wastewater Treatment: From Basic Principles to Applications discusses mechanistic details of ozone reactions as much as they are known to date and applies them to the large body of studies on micropollutant degradation (such as pharmaceuticals and endocrine disruptors) that is already available. Extensively quoting the literature and updating the available compilation of ozone rate constants gives the reader a text at hand on which his research can be based. Moreover, those that are responsible for planning or operation of ozonation steps in drinking water and wastewater treatment plants will find salient information in a compact form that otherwise is quite disperse. A critical compilation of rate constants for the various classes of compounds is given in each chapter, including all the recent publications. This is a very useful source of information for researchers and practitioners who need kinetic information on emerging contaminants. Furthermore, each chapter contains a large selection of examples of reaction mechanisms for the transformation of micropollutants such as pharmaceuticals, pesticides, fuel additives, solvents, taste and odor compounds, cyanotoxins. Authors: Prof. Dr. Clemens von Sonntag, Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, and Instrumentelle Analytische Chemie, Universität Duisburg-Essen, Essen, Germany and Prof. Dr. Urs von Gunten, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, and Ecole Polytechnique Federal de Lausanne, Lausanne, Switzerland.
Download or read book Coagulation and Flocculation in Water and Wastewater Treatment written by John Bratby and published by IWA Publishing. This book was released on 2006-10-15 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coagulation and Flocculation in Water and Wastewater Treatment provides a comprehensive account of coagulation and flocculation techniques and technologies in a single volume covering theoretical principles to practical applications. Thoroughly revised and updated since the 1st Edition it has been progressively modified and increased in scope to cater for the requirements of practitioners involved with water and wastewater treatment. A thorough gamut of treatment scenarios is attempted, including turbidity, color and organics removal, including the technical aspects of enhanced coagulation. The effects of temperature and ionic content are described as well as the removal of specific substances such as arsenic and phosphorus. Chemical phosphorus removal is dealt with in detail, Rapid mixing for efficient coagulant utilization, and flocculation are dealt with in specific chapters. Water treatment plant waste sludge disposal is dealt with in considerable detail, in an Appendix devoted to this subject. Invaluble for water scientists, engineers and students of this field, Coagulation and Flocculation in Water and Wastewater Treatment is a convenient reference handbook in the form of numerous examples and appended information.
Download or read book Mutagenic Impurities written by Andrew Teasdale and published by John Wiley & Sons. This book was released on 2022-02-15 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn to implement effective control measures for mutagenic impurities in pharmaceutical development In Mutagenic Impurities: Strategies for Identification and Control, distinguished chemist Andrew Teasdale delivers a thorough examination of mutagenic impurities and their impact on the pharmaceutical industry. The book incorporates the adoption of the ICH M7 guideline and focuses on mutagenic impurities from both a toxicological and analytical perspective. The editor has created a primary reference for any professional or student studying or working with mutagenic impurities and offers readers a definitive narrative of applicable guidelines and practical, tested solutions. It demonstrates the development of effective control measures, including chapters on the purge tool for risk assessment. The book incorporates a discussion of N-Nitrosamines which was arguably the largest mutagenic impurity issue ever faced by the pharmaceutical industry, resulting in the recall of Zantac and similar drugs resulting from N-Nitrosamine contamination. Readers will also benefit from the inclusion of: A thorough introduction to the development of regulatory guidelines for mutagenic and genotoxic impurities, including a historical perspective on the development of the EMEA guidelines and the ICH M7 guideline An exploration of in silico assessment of mutagenicity, including use of structure activity relationship evaluation as a tool in the evaluation of the genotoxic potential of impurities A discussion of a toxicological perspective on mutagenic impurities, including the assessment of mutagenicity and examining the mutagenic and carcinogenic potential of common synthetic reagents Perfect for chemists, analysts, and regulatory professionals, Mutagenic Impurities: Strategies for Identification and Control will also earn a place in the libraries of toxicologists and clinical safety scientists seeking a one-stop reference on the subject of mutagenic impurity identification and control.
Download or read book Guidelines for Drinking water Quality written by World Health Organization and published by World Health Organization. This book was released on 1993 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume describes the methods used in the surveillance of drinking water quality in the light of the special problems of small-community supplies, particularly in developing countries, and outlines the strategies necessary to ensure that surveillance is effective.
