Download or read book Etude des m canismes d limination de la mati re organique des eaux de surface par coagulation l aide de sels d aluminium ou de fer written by Astride Vilge-Ritter and published by . This book was released on 1997 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA MATIERE ORGANIQUE NATURELLE (MON) EST ASSOCIEE A DE NOMBREUX PROBLEMES : GOUTS, ODEURS, REVISVISCENCE BACTERIENNE... L'ELIMINATION DE LA MON EST DONC UN OBJECTIF ESSENTIEL POUR ASSURER LA QUALITE DES EAUX POTABLES, ELLE EST POSSIBLE GRACE AU PROCEDE DE COAGULATION-FLOCULATION, ENTRE AUTRES. LES REACTIONS DE COAGULATION-FLOCULATION DE LA MON DE 2 EAUX ONT ETE EFFECTUEES A L'AIDE DE SELS DE FER(III) ET D'ALUMINIUM(III) SUR DE LARGES GAMMES DE PH ET DOSES DE COAGULANT. LES TECHNIQUES UTILISEES ONT PERMIS DE MESURER L'EFFICACITE DE LA COAGULATION EN FONCTION DES CONDITIONS OPERATOIRES, DE PRECISER LA NATURE CHIMIQUE DE LA MON CONTENUE DANS LES 2 EAUX ET DANS LES FLOCS, D'ETUDIER LES INTERACTIONS MON-COAGULANT A L'ECHELLE LOCALE ET DE DETERMINER LES STRUCTURES SEMI LOCALE ET MACROSCOPIQUE DES FLOCS FORMES. POUR LES DEUX TYPES D'EAU ETUDIEES, LE CLASSEMENT DES COAGULANTS EN FONCTION DE LEUR EFFICACITE EST FECL#3 > WAC HB > SULFATE D'ALUMINIUM. LE PH OPTIMAL EST DE 5,5 POUR LE FE(III) ET AUTOUR DE 6-7 POUR LES COAGULANTS A BASE D'AL, LA DOSE ETANT NATURELLEMENT DEPENDANTE DU COD. POUR LA MON DE L'EAU DE SEINE, NOUS AVONS MIS EN EVIDENCE UNE SELECTIVITE DES COAGULANTS VIS A VIS DE CERTAINS TYPES DE BIOPOLYMERES, QUI N'EST PAS VISIBLE POUR L'EAU DE BARRAGE. CECI A ETE ATTRIBUE AU FAIT QUE DANS L'EAU DE SEINE LES DIFFERENTES CLASSES DE BIOPOLYMERES CORRESPONDENT A DES MOLECULES BIEN INDIVIDUALISEES, TANDIS QUE LA MON DE L'EAU DE BARRAGE EST PLUS HOMOGENE. LA SPECIATION DES COAGULANTS AU SEIN DES FLOCS INDIQUE CLAIREMENT UNE INHIBITION DE L'HYDROLYSE DES CATIONS METALLIQUES DUES A LA PRESENCE DE MON. LA SPECIATION DE CES METAUX N'EST PAS MODIFIEE PAR L'AUGMENTATION DE PH, MONTRANT AINSI QUE, DANS TOUS LES CAS, LE PRINCIPAL MECANISME D'ELIMINATION DE LA MON EST LA COMPLEXATION. LA STRUCTURE DES FLOCS EST REGIE PAR LA MON. LES OBJETS FORMES ONT DES DIMENSIONS FRACTALES ELEVEES QUELLE QUE SOIT L'ECHELLE D'OBSERVATION. LA STRUCTURATION DES FLOCS SUIT CEPENDANT UN MECANISME DIFFERENT EN FONCTION DE L'ECHELLE. AU COURS DE CE TRAVAIL, NOUS AVONS DONC DEMONTRE LE ROLE PREPONDERANT DE LA MON DANS LA COAGULATION.

Download or read book Elimination de l arsenic par coagulation floculation et lectrocoagulation d eaux faiblement min ralis es written by Virginie Pallier and published by . This book was released on 2008 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'arsenic est omniprésent dans l'environnement : sa mobilisation entraîne une contamination des ressources en eaux et par conséquent une augmentation des risques pour la santé humaine. L'eau de boisson représentant la principale voie d'exposition aux formes inorganiques de l'arsenic, sa concentration maximale admissible dans l'eau potable a donc été réduite à 10 μg/L, nécessitant d'adapter les méthodes de dosage et de développer et optimiser des procédés de traitement. En fonction de la matrice de l'échantillon, l'As(III) est ici dosé par spectrométrie d'absorption atomique à génération d'hydrures ou par polarographie par redissolution cathodique à impulsions carrées. Les procédés de coagulation floculation avec le Fe(III) et d'électrocoagulation optimisés présentent une efficacité dépendante de la spéciation de l'arsenic, du pH, de la dose de traitement appliquée et de la présence de matière organique. Ces paramètres influencent les mécanismes réactionnels mis enjeu.

Download or read book M canisme de coagulation et de floculation de suspensions d argiles dilu es rencontr es en traitement des eaux written by Moïse Désiré Dihang and published by . This book was released on 2007 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mécanismes de coagulation et de floculation de suspensions d'argiles diluées rencontrées en traitement des eaux La latérite est la principale matière en suspension dans les eaux de rivière (eaux brutes) des régions tropicales. Son élimination est le principal enjeu du processus de potabilisation de ces eaux. La latéritique est une argile qui confère à l'eau un aspect trouble de couleur rougeâtre, y compris à de très faibles concentrations. Au-delà de 160 NTU de turbidité initiale (TI), les particules de latérite en suspension subissent une auto-floculation qui modifie les paramètres de coagulation et de floculation respectivement par des sels métalliques hydrolysables et des polymères. Ainsi, en-deçà de 160 NTU, la concentration critique de coagulation (CCC) de la latérite par le chlorure d'aluminium augmente avec la TI, tandis qu'au-delà de 160 NTU, la CCC diminue quand la TI augmente. La concentration maximale de coagulant ajoutée à la CCC et quelle que soit la TI est de l'ordre du quart des valeurs prescrites par les normes pour l'eau potable. Le potentiel Zeta semble être un paramètre plus pertinent que la turbidité résiduelle (TR) pour étudier la coagulation de telles suspensions. Dans tous les cas et quelle que soit la TI, le potentiel Zéta à la CCC est proche -20 MV. La floculation, par des polyacrylamides non ioniques (PAM-N), cationiques (PAM-C), ou anioniques (PAM-A) de poids moléculaire élevé favorise la réduction de la turbidité des suspensions coagulées. Cette réduction est indépendante de la quantité de polymère ajouté lorsque la suspension est coagulée à la CCC. Dans les autres cas, la réduction de la turbidité dépend de la concentration de polymère ajouté. Au contraire de suspensions de TI faible, la floculation n'améliore pas sensiblement l'efficacité de la coagulation pour les suspensions de TI élevée. A de faibles concentrations, PAM-N et PAM-A ne modifient pas sensiblement le potentiel Zeta des particules de latérite, ce qui permet d'utiliser le potentiel zéta comme un paramètre adéquat pour le suivie de la déstabilisation de suspensions de latérite par coagulation et floculation. Les particules de latérite sont par contre très sensibles à la présence de PAM-C, qui induit des inversions de charge de surface même à très faibles concentrations...

Download or read book Etude de l limination de l acide fulvique par coagulation floculation ou filtration contact written by Shaojie Jiang and published by . This book was released on 1997 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'élimination de l'acide fulvique (af) est étudiée par des méthodes physico-chimiques avec des eaux synthétiques contenant de l'af commercial (10 mg/l en général). La coagulation-floculation de l'af par le sulfate d'aluminium (alun), le chlorure ferrique où le polychlorosulfate d'aluminium (wac hb) et l'influence de la bentonite et du calcium sont étudiées en jar-test. Le wac hb est efficace dans une large gamme de ph surtout pour ph>7 mais l'alun n'est efficace qu'a ph 6-7 ; le fer reste le coagulant le plus efficace a ph

Download or read book Ozone in Water Treatment written by Bruno Langlais and published by Routledge. This book was released on 2019-07-16 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the advent of the Safe Drinking Water Act Amendments of 1986, many water utilities are reexamining their water treatment practices. Upcoming new regulations on disinfection and on disinfection by-products, in particular, are the primary driving forces for the big interest in ozone. It appears that ozone, with its strong disinfection capabilities, and apparently lower levels of disinfection by-products (compared to other disinfectants), may be the oxidant/disinfectant of choice. Many utilities currently using chlorine for oxidation may need to switch due to chlorine by-product concerns. Utilities using chloramines may need to use ozone to meet CT requirements. This book, prepared by 35 international experts, includes current technology on the design, operation, and control of the ozone process within a drinking water plant. It combines almost 100 years of European ozone design and operating experience with North American design/operations experience and the North American regulatory and utility operational environment. Topics covered include ozone chemistry, toxicology, design consideration, engineering aspects, design of retrofit systems, and the operation and economics of ozone technology. The book contains a "how to" section on ozone treatability studies, which explains what information can be learned using treatability studies, at what scale (bench, pilot, or demonstration plant), and how this information can be used to design full-scale systems. It also includes valuable tips regarding important operating practices, as well as guidance on retrofits and the unique issues involved with retrofitting the ozone process. With ozone being one of the hottest areas of interest in drinking water, this book will prove essential to all water utilities, design engineers, regulators, and plant managers and supervisors.

Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.

Download or read book Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.

Download or read book Faecal Sludge Management written by Linda Strande and published by IWA Publishing. This book was released on 2014-08-15 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.

Download or read book Aquatic Humic Substances written by I. H. Suffet and published by . This book was released on 1989 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here is a cohesive compilation of recent research results into the many aspects of water purification. Major sections cover the characterization and environmental impact of aquatic humic substances, their reactions in natural water and sediments, and their influences on water treatment. Topics examined include hazardous waste chemicals, water solubility enhancement, sorption, metal speciation, and photochemistry. Specific types of treatment processes are also described.

Download or read book Metal Pollution in the Aquatic Environment written by U. Förstner and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aquatic chemistry is becoming both a rewarding and substantial area of inquiry and is drawing many prominent scientists to its fold. Its literature has changed from a compilation of compositional tables to studies of the chemical reactions occurring within the aquatic environments. But more than this is the recognition that human society in part is determining the nature of aquatic systems. Since rivers deliver to the world ocean most of its dissolved and particulate components, the interactions of these two sets of waters determine the vitality of our coastal waters. This significant vol ume provides not only an introduction to the dynamics of aquatic chem istries but also identifies those materials that jeopardize the resources of both the marine and fluvial domains. Its very title provides its emphasis but clearly not its breadth in considering natural processes. The book will be of great value to those environmental scientists who are dedicated to keeping the resources of the hydrosphere renewable. As the size of the world population becomes larger in the near future and as the uses of materials and energy show parallel increases, the rivers and oceans must be considered as a resource to accept some of the wastes of society. The ability of these waters and the sediments below them to accommodate wastes must be assessed continually. The key questions relate to the capacities of aqueous systems to carry one or more pollutants.

Download or read book Equilibrium Concepts in Natural Water Systems written by and published by . This book was released on 1967 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhanced Coagulation and Enhanced Precipitative Softening Guidance Manual written by and published by DIANE Publishing. This book was released on 1999 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arsenic in Drinking Water written by National Research Council and published by National Academies Press. This book was released on 2001-11-26 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: Having safe drinking water is important to all Americans. The Environmental Protection Agency's decision in the summer of 2001 to delay implementing a new, more stringent standard for the maximum allowable level for arsenic in drinking water generated a great deal of criticism and controversy. Ultimately at issue were newer data on arsenic beyond those that had been examined in a 1999 National Research Council report. EPA asked the National Research Council for an evaluation of the new data available. The committee's analyses and conclusions are presented in Arsenic in Drinking Water: 2001 Update. New epidemiological studies are critically evaluated, as are new experimental data that provide information on how and at what level arsenic in drinking water can lead to cancer. The report's findings are consistent with those of the 1999 report that found high risks of cancer at the previous federal standard of 50 parts per billion. In fact, the new report concludes that men and women who consume water containing 3 parts per billion of arsenic daily have about a 1 in 1,000 increased risk of developing bladder or lung cancer during their lifetime.

Download or read book Sustainable Desalination and Water Reuse written by Eric M.V. Hoek and published by Morgan & Claypool Publishers. This book was released on 2021-06-18 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past half century, reverse osmosis (RO) has grown from a nascent niche technology into the most versatile and effective desalination and advanced water treatment technology available. However, there remain certain challenges for improving the cost-effectiveness and sustainability of RO desalination plants in various applications. In low-pressure RO applications, both capital (CAPEX) and operating (OPEX) costs are largely influenced by product water recovery, which is typically limited by mineral scale formation. In seawater applications, recovery tends to be limited by the salinity limits on brine discharge and cost is dominated by energy demand. The combination of water scarcity and sustainability imperatives, in many locations, is driving system designs towards minimal and zero liquid discharge (M/ZLD) for inland brackish water, municipal and industrial wastewaters, and even seawater desalination. Herein, we review the basic principles of RO processes, the state-of-the-art for RO membranes, modules and system designs as well as methods for concentrating and treating brines to achieve MLD/ZLD, resource recovery and renewable energy powered desalination systems. Throughout, we provide examples of installations employing conventional and some novel approaches towards high recovery RO in a range of applications from brackish groundwater desalination to oil and gas produced water treatment and seawater desalination.

Download or read book Microbial Quality of Water Supply in Distribution Systems written by Edwin E. Geldreich and published by CRC Press. This book was released on 1996-01-18 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hidden problems, buried deep in the pipe networks of water distribution systems, are very serious potential threats to water quality. Microbial Quality of Water Supply in Distribution Systems outlines the processes and issues related to the degradation of water quality upon passage through networks of pipes, storage reservoirs, and standpipes on its way to the consumer. The risks associated with biofilm accumulation, bacteria, and other contaminants are discussed in great detail. In addition to its excellent microbiological coverage of organisms in drinking water and biofilms in distribution systems, Microbial Quality of Water Supply in Distribution Systems provides clear treatments of the technical and public communication issues most commonly affecting the quality of water and water supply systems. The inclusion of numerous case histories in this new book makes it a complete reference source for anyone concerned with water quality and water distribution systems.

Download or read book Modern Size Exclusion Liquid Chromatography written by Andre Striegel and published by John Wiley & Sons. This book was released on 2009-07-31 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Second Edition of Modern Size-Exclusion Chromatography offers a complete guide to the theories, methods, and applications of size-exclusion chromatography. It provides an unparalleled, integrated, up-to-date treatment of gel permeation and gel filtration chromatography. With its detailed descriptions of techniques, data handling, compilations of information on columns and column packings, and tables of important solvents and reference materials, the book offers readers everything they need to take full advantage of this popular macromolecular characterization technique. Since publication of the first edition in 1979, there have been many important advances in the field of size-exclusion chromatography. This Second Edition brings the book thoroughly up to date, with expert coverage of: New and emerging industrial and research applications Practical aspects of size-exclusion chromatography (SEC) and multidetector and multidimensional SEC technologies for polymer architecture and copolymer analysis Updated information on the latest equipment and techniques New best practices for the lab SEC in relation to polymer characterization techniques such as GPEC, LCCC, and rheology Throughout the text, detailed examples guide you step by step through all the latest techniques and applications. With its extensive revisions and updates written by leading experts and pioneers in the field, Modern Size-Exclusion Liquid Chromatography remains the definitive resource for the broad range of researchers and scientists who use HPLC and GPC methods.

Download or read book Seawater Pretreatment written by Nikolay Voutchkov and published by . This book was released on 2010 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: