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Book Biological Nutrient Removal of Domestic Sewage Using Combined Anaerobic anoxic aerobic Reactor

Download or read book Biological Nutrient Removal of Domestic Sewage Using Combined Anaerobic anoxic aerobic Reactor written by Maheran Ismail and published by . This book was released on 2001 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall objectives of this study is to develop an innovative technology to treat nutrients especially and phophorous in domestic wastewater. This process is called the Anaerobic-anoxic-aerobic (AAA). Biological nitrification-denitrification and phosphorus removal in a single reactor have been shown applicable to treat nutrients with some modifications in an aerobic zonem where 'cosmo-ball' media were intoduced to enhance growth. The vertical reactor with 'up flow' influent was operated using a continuos system with an anaerobic-anoxic-aerobic zone sequence. This experiment was operated at HRT total of hours where the anaerobic, anoxic and aerobic zone takes 1.5, 1.5 and 4 hours respectively. The experimental run was conducted in the Enviromental laboratory using raw samples from an Extended Aeration treatment plant at Serdang Raya, Sri Kembangan, Selangor. The results showed that nitrification-denitrification process could be achieved using this anaerobic-anoxic-aerobic (AAA) reactor with 63% NH4-N removal and 51% PO4 removal. Removal of BOD, COD, TSS, VSS were 84%, 78%, 85% and 83% respectively. The results obtained also shows that organic and pH significance effects on nutrient removal for a medium strength wastewater. The treatment of sewage effluent was also carried out in anaerobix-anoxic-aerobic reactor to study the kinetics parameters for nitrification and denitrification processes and the results obtained were: YN = 0.041 mg VSS/mg NH4, Kd = 0.0417 day-1, μm = 1.6470 day-1, KN = 0.8996 mg/l (kinetic parameter for denitrification). Meanwhile, parameters kinetic for denitrification were: YD = 0.017 mg VSS/mg NO3, Kd1 = 0.0014 day-1, μm1 = 0.00407 day -1, KD = 8.036 mg/l. It has been found that there reactor was succeded in removing nutrients from the sewage.

Book Nutrient Removal from Wastewaters

Download or read book Nutrient Removal from Wastewaters written by Nigel J. Horan and published by CRC Press. This book was released on 1994-10-06 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topics in the book include: novel processes, removal of ammonia and nitrogen, retrofitting/upgrading treatment plants for nutrient removal, and operating experiences at full-scale plants. Nutrient removal from wastewaters is a critical topic in every region. Problems can arise from domestic sewage, industrial wastewater, or rainwater runoff.

Book Activated Sludge Models

    Book Details:
  • Author : The IWA Task Group on Mathematical Modelling for Design and Operation of Biological Wastewater Treatment
  • Publisher : IWA Publishing
  • Release : 2000-05-31
  • ISBN : 9781900222242
  • Pages : 132 pages

Download or read book Activated Sludge Models written by The IWA Task Group on Mathematical Modelling for Design and Operation of Biological Wastewater Treatment and published by IWA Publishing. This book was released on 2000-05-31 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has been produced to give a total overview of the Activated Sludge Model (ASM) family at the start of 2000 and to give the reader easy access to the different models in their original versions. It thus presents ASM1, ASM2, ASM2d and ASM3 together for the first time. Modelling of activated sludge processes has become a common part of the design and operation of wastewater treatment plants. Today models are being used in design, control, teaching and research. Contents ASM3: Introduction, Comparison of ASM1 and ASM3, ASM3: Definition of compounds in the model, ASM3: Definition of processes in the Model, ASM3: Stoichiometry, ASM3: Kinetics, Limitations of ASM3, Aspects of application of ASM3, ASM3C: A Carbon based model, Conclusion ASM 2d: Introduction, Conceptual Approach, ASM 2d, Typical Wastewater Characteristics and Kinetic and Stoichiometric Constants, Limitations, Conclusion ASM 2: Introduction, ASM 2, Typical Wastewater Characteristics and Kinetic and Stoichiometric Constants, Wastewater Characterization for Activated Sludge Processes, Calibration of the ASM 2, Model Limitations, Conclusion, Bibliography ASM 1: Introduction, Method of Model Presentation, Model Incorporating Carbon Oxidation Nitrification and Denitrification, Characterization of Wastewater and Estimation of Parameter Values, Typical Parameter Ranges, Default Values, and Effects of Environmental Factors, Assumptions, Restrictions and Constraints, Implementation of the Activated Sludge Model Scientific and Technical Report No.9

Book Characterizing Mechanisms of Simultaneous Biological Nutrient Removal During Wastewater Treatment

Download or read book Characterizing Mechanisms of Simultaneous Biological Nutrient Removal During Wastewater Treatment written by P. F. Strom and published by IWA Publishing. This book was released on 2004-01-01 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Simultaneous biological nutrient removal (SBNR) is the removal of nitrogen and/or phosphorus in excess of that required for biomass synthesis in biological wastewater treatment systems where there are no defined anaerobic and/or anoxic zones. The hypothesis is that one or more of three mechanisms is responsible within individual systems: variations in the bioreactor macroenvironment created by the mixing pattern, gradients within the floc microenvironment, and/or novel microorganism activity. Understanding of the mechanisms of SBNR can be expected to lead to improved efficiency and reliability in its application. Preliminary work documented SBNR in 7 full-scale OrbalTM closed loop bioreactors. A batch assay demonstrated that novel microorganism activity was of little importance in SBNR at the three plants tested. While the floc microenvironment likely plays an important role in nitrogen removal in such plants, it cannot explain phosphorus removal. A computational fluid dynamics (CFD) model was developed to elucidate the role of the bioreactor macroenvironment in SBNR. This is the first reported application of CFD to activated sludge biological wastewater treatment. Although the software and computational requirements limited model complexity, it still simulated the creation of dissolved oxygen gradients within the system, demonstrating that the anaerobic zones required for SBNR could occur.

Book Biological Nutrients  Removal in the Anaerobic Anoxic Oxic Wastewater Treatment Process

Download or read book Biological Nutrients Removal in the Anaerobic Anoxic Oxic Wastewater Treatment Process written by Changyong Wu and published by Nova Science Publishers. This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Anaerobic-anoxic-oxic (A2/O) is one of the most widely used processes in municipal wastewater treatment plants for simultaneous biological nitrogen and phosphorus removal. The A2/O process has many advantages, such as simple configuration and short hydraulic retention time (HRT), etc. In addition, it is easy to operate. Therefore, A2/O will be continuously chosen as the main option in all kinds of newly designed and built wastewater treatment plants. Though the A2/O process has been used widely, it has some inherent contradictions which are difficult to overcome. For example, the contradiction between substrate competition and SRT makes the high nitrogen and phosphorus removal unable to be achieved simultaneously. As a result, the removal efficiency of the system cannot be further improved. In the past 10 years in China, the wastewater quality very obviously changed with the improvement of living conditions. At present, municipal wastewater with a low C/N ratio is rather common in most countries in the world. The lack of a carbon source will make the inherent contradictions of the A2/O process becomes serious. Therefore, the conventional design parameters of the A2/O process are needed to adjust or the configuration of the A2/O process should change to fit the change of the wastewater quality. According to this, this book systematically describes how to improve the nitrogen and phosphorus removal efficiency of municipal wastewater with low C/N ratio, and effectively utilize the carbon resource in the influent of wastewater. This publication is useful for students, researchers and engineers whose major focus is municipal and the environment"--

Book Handbook of Environmental Materials Management

Download or read book Handbook of Environmental Materials Management written by Chaudhery Mustansar Hussain and published by Springer. This book was released on 2019-06-03 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reference work analyzes and assesses global environmental management techniques for environmental materials with a focus on their performance and economic benefits, proposing eco-friendly solutions and designating policies that will sustain the environment for future generations. It addresses management of environmental materials as not only a complex anthropogenic problem, but also as an expensive problem that needs to be managed sustainably. Simultaneously, it considers the environmental and economic benefits involved in the high levels of investment and operation costs required to develop effective materials collection and management systems in modern society.

Book Bioelectrochemical Systems

Download or read book Bioelectrochemical Systems written by Korneel Rabaey and published by IWA Publishing. This book was released on 2009-12-01 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the context of wastewater treatment, Bioelectrochemical Systems (BESs) have gained considerable interest in the past few years, and several BES processes are on the brink of application to this area. This book, written by a large number of world experts in the different sub-topics, describes the different aspects and processes relevant to their development. Bioelectrochemical Systems (BESs) use micro-organisms to catalyze an oxidation and/or reduction reaction at an anodic and cathodic electrode respectively. Briefly, at an anode oxidation of organic and inorganic electron donors can occur. Prime examples of such electron donors are waste organics and sulfides. At the cathode, an electron acceptor such as oxygen or nitrate can be reduced. The anode and the cathode are connected through an electrical circuit. If electrical power is harvested from this circuit, the system is called a Microbial Fuel Cell; if electrical power is invested, the system is called a Microbial Electrolysis Cell. The overall framework of bio-energy and bio-fuels is discussed. A number of chapters discuss the basics – microbiology, microbial ecology, electrochemistry, technology and materials development. The book continues by highlighting the plurality of processes based on BES technology already in existence, going from wastewater based reactors to sediment based bio-batteries. The integration of BESs into existing water or process lines is discussed. Finally, an outlook is provided of how BES will fit within the emerging biorefinery area.

Book Biological Wastewater Treatment

Download or read book Biological Wastewater Treatment written by Mogens Henze and published by IWA Publishing (International Water Assoc). This book was released on 1881 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: For information on the online course in Biological Wastewater Treatment from UNESCO-IHE, visit: http://www.iwapublishing.co.uk/books/biological-wastewater-treatment-online-course-principles-modeling-and-design Over the past twenty years, the knowledge and understanding of wastewater treatment have advanced extensively and moved away from empirically-based approaches to a first principles approach embracing chemistry, microbiology, physical and bioprocess engineering, and mathematics. Many of these advances have matured to the degree that they have been codified into mathematical models for simulation with computers. For a new generation of young scientists and engineers entering the wastewater treatment profession, the quantity, complexity and diversity of these new developments can be overwhelming, particularly in developing countries where access is not readily available to advanced level tertiary education courses in wastewater treatment. Biological Wastewater Treatment addresses this deficiency. It assembles and integrates the postgraduate course material of a dozen or so professors from research groups around the world that have made significant contributions to the advances in wastewater treatment. The book forms part of an internet-based curriculum in biological wastewater treatment which also includes: Summarized lecture handouts of the topics covered in book Filmed lectures by the author professors Tutorial exercises for students self-learning Upon completion of this curriculum the modern approach of modelling and simulation to wastewater treatment plant design and operation, be it activated sludge, biological nitrogen and phosphorus removal, secondary settling tanks or biofilm systems, can be embraced with deeper insight, advanced knowledge and greater confidence.

Book Biological Nutrient Removal from Municipal and Industrial Wastewater Using a Twin Circulating Fluidized Bed Bioreactor

Download or read book Biological Nutrient Removal from Municipal and Industrial Wastewater Using a Twin Circulating Fluidized Bed Bioreactor written by Mehran Andalib and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Biological nutrient removal (BNR) refers to removal of carbon (C), nitrogen (N) and phosphorus (P) from wastewater (WW) by the aid of various microorganisms. Because of the public concern for the environment C, N and P effluent standards have become stricter. Different BNR processes such as suspended growth and attached growth have been studied during the last three decades in order to meet the increasingly stringent discharge standards. In this work, two novel processes called Twin Fluidized Bed Bioreactor (TFBBR) and Twin Circulating Fluidized Bed Bioreactor (TCFBBR) were developed and tested for BNR from municipal WW. Both TFBBR and TCFBBR comprise of an anoxic column and an aerobic column with particle recirculation between the two reactors achieved mechanically (TFBBR) and hydraulically (TCFBBR). Moreover, a newly developed system called Anaerobic Fluidized-Circulating Fluidized Bed Bioreactor (AF-CFBBR) was developed and tested to accomplish BNR from high strength industrial WW. AF-CFBBR comprises of an anaerobic, an anoxic and an aerobic columns. In all three aforementioned systems, fine carrier media are employed for biofilm attachment. After the development of biofilm, the particles are called biofilm-coated particles. TFBBR and TCFBBR were operated at organic, nitrogen and phosphorus loading rates (OLR, NLR and PLR) of up to 2.8 kg COD/m3×d and 4.5 kg COD/m3×d, 0.3 kg N/m3×d and 0.5 kg N/m3×d and 0.041 kg P/m3×d respectively to study the performance of the system with respect to biological nutrient removal. The nitrification rates based on biofilm surface area in TFBBR and TCFBBR were 0.91 g N/m2×d and 1.26 g N/m2×d respectively and the denitrification rates based on biofilm surface area in TFBBR and TCFBBR were 0.65 g N/m2×d and 1.32 g N/m2×d respectively. Both systems removed>96% organic matter, 84%-88% nitrogen and 12%-50% phosphorus at overall hydraulic retention time of (HRT) 2h. TFBBR and TCFBBR achieved long SRTs of 72-108 d and 37-40 d respectively, which rationalized the very low observed yield of 0.06-0.07 g VSS/g COD and 0.09-0.1 g VSS/g COD. The AF-CFBBR demonstrated 99.7% COD removal, 84% nitrogen removal, with a very low sludge yield of 0.017 g VSS/g COD while treating a wastewater containing 10700 mg COD/L and 250-300 mg NH3-N/L. The system was operated at an organic loading rate (OLR) of 35 kg COD/m3·d based on the AF volume and 1.1 kg N/m3·d based on the CFBBR at an overall HRT of less than 12 h in the AF-CFBBR. The nitrification, denitrification and organic removal rates based on aerobic, anoxic and anaerobic biofilm surface area in AF-CFBBR respectively were 2.6 g N/m2×d, 9.03 g N/m2×d and 12.1 g COD/m2×d. Additionally, the inhibitory effect of nitrate on methanogenic activities in a high rate anaerobic fluidized bed with organic loading rate of above 35 kg COD/m3·d was studied in order to evaluate the feasibility of simultaneous denitrification and methanogenic activities (SDM) in a high rate anaerobic system. Terminal settling velocity and bed expansion of biofilm-coated particles as the two main hydrodynamic criteria in a fluidized bed, were studied. Archimedes was superior to Reynolds number for drag coefficient and bed expansion definitions. A new equation for determining drag force on fluidized bed bio-film coated particle (Fd) as an explicit function of terminal settling velocity was generated based on Archimedes numbers (Ar) of the biofilm coated particle. The proposed equation adequately predicted the terminal settling velocity of other literature data with an accuracy of>90%. A new equation based on Archimedes number was proposed to calculate bed expansion index of biofilm-coated particles, which predicted the existing experimental data with less standard error than all other literature equations that related bed expansion to Reynolds number. A two-phase and three-phase predictive fluidization model based on the characteristics of a system such as media type and size, flow rates, and reactor cross sectional area was proposed to calculate bed expansion, solid, liquid and gas hold up, specific surface area of the biofilm particles. The model was subsequently linked to 1d AQUIFAS APP software (Aquaregen) to model two and three phase fluidized bed bioreactors. The model was validated for biological nutrient removal using the experimental data from a Twin Circulating Fluidized Bed Bioreactors (TCFBBR) treating synthetic and municipal wastewater. Two-sided t-tests showed that there were no statistically significant difference between the experimental and the modeled TCOD, SCOD, NH3-N, NOx-N.

Book Advances in Water and Wastewater Treatment

Download or read book Advances in Water and Wastewater Treatment written by Martin P. Wanielista and published by Butterworth-Heinemann. This book was released on 1978 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Anaerobic Reactors

    Book Details:
  • Author : Carlos Augustos de Lemos Chernicharo
  • Publisher : IWA Publishing
  • Release : 2007-03-30
  • ISBN : 1843391643
  • Pages : 189 pages

Download or read book Anaerobic Reactors written by Carlos Augustos de Lemos Chernicharo and published by IWA Publishing. This book was released on 2007-03-30 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anaerobic Reactors is the forth volume in the series Biological Wastewater Treatment. The fundamentals of anaerobic treatment are presented in detail, including its applicability, microbiology, biochemistry and main reactor configurations. Two reactor types are analysed in more detail, namely anaerobic filters and especially UASB (upflow anaerobic sludge blanket) reactors. Particular attention is also devoted to the post-treatment of the effluents from the anaerobic reactors. The book presents in a clear and informative way the main concepts, working principles, expected removal efficiencies, design criteria, design examples, construction aspects and operational guidelines for anaerobic reactors. About the series: The series is based on a highly acclaimed set of best selling textbooks. This international version is comprised by six textbooks giving a state-of-the-art presentation of the science and technology of biological wastewater treatment. Other titles in the series are: Volume 1: Waste Stabilisation Ponds; Volume 2: Basic Principles of Wastewater Treatment; Volume 3: Waste Stabilization Ponds; Volume 5: Activated Sludge and Aerobic Biofilm Reactors; Volume 6: Sludge Treatment and Disposal

Book Activated Sludge and Aerobic Biofilm Reactors

Download or read book Activated Sludge and Aerobic Biofilm Reactors written by Marcos Von Sperling and published by IWA Publishing. This book was released on 2007-03-30 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated Sludge and Aerobic Biofilm Reactors is the fifth volume in the series Biological Wastewater Treatment. The first part of the book is devoted to the activated sludge process, covering the removal of organic matter, nitrogen and phosphorus.A detailed analysis of the biological reactor (aeration tank) and the final sedimentation tanks is provided. The second part of the book covers aerobic biofilm reactors, especially trickling filters, rotating biological contractors and submerged aerated biofilters. For all the systems, the book presents in a clear and informative way the main concepts, working principles, expected removal efficiencies, design criteria, design examples, construction aspects and operational guidelines. About the series: The series is based on a highly acclaimed set of best selling textbooks. This international version is comprised by six textbooks giving a state-of-the-art presentation of the science and technology of biological wastewater treatment. Other titles in the series are: Volume 1: Waste Stabilisation Ponds; Volume 2: Basic Principles of Wastewater Treatment; Volume 3: Waste Stabilization Ponds; Volume 4: Anaerobic Reactors; Volume 6: Sludge Treatment and Disposal

Book The Combined Sharon Anammox Process

Download or read book The Combined Sharon Anammox Process written by L. G. J. M. van Dongen and published by IWA Publishing. This book was released on 2001-09-30 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wastewater treatment management, alongside many other industries, is seeking to attain a higher degree of sustainability for its processes by focusing on new technologies which minimise the consumption of resources or even recover them from the wastewater. Conventional removal of ammonium requires usually large amounts of energy for aeration and organic carbon for denitrification. This report focuses on making the nitrogen-removal process more sustainable. This can be achieved by a partial oxidation of ammonium to nitrite, after which the nitrate produced can be converted into nitrogen gas with the rest of ammonium under anoxic conditions. The treatment of nitrogen-rich water can be carried out beneficially by a combination of the Sharon process with the Anammox process. In this combined process less than 50% of the aeration energy is needed, no COD is required and an insignificant amount of sludge is produced. In this Report the potential of using this technology for the treatment of water arising from sludge treatment at a municipal wastewater treatment plant (WWTP) is evaluated and the results of the operation of the system are described in detail. This reject water contains a significant fraction of the N-load towards the wastewater treatment plant. The results are used in an economic evaluation of a potential full scale installation. The Combined Sharon/Anammox Process Report will provide an invaluable source of information for all those concerned with the efficient and sustainable treatment of wastewater including plant managers, process designers, consultants and researchers.

Book ANAEROBIC   AEROBIC TREATMENT OF DOMESTIC SEWAGE

Download or read book ANAEROBIC AEROBIC TREATMENT OF DOMESTIC SEWAGE written by and published by . This book was released on 2009 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt: Domestic wastewater is the most abundant type of wastewater. Direct discharge of untreated domestic wastewater has environmental and public health risks due to the presence of organics, nutrients and pathogens. Application of anaerobic processes for the treatment of domestic sewage, which at present is largely treated by aerobic processes, has drawn considerable attention recently. Anaerobic processes can be applied for the removal of organic matter (methanogenesis) and nitrogen (anaerobic ammonium oxidation (Anammox)). The toxicity of fluoride to methanogenesis was investigated. The results indicate that acetoclastic were more susceptible to fluoride than hydrogenotrophic methanogens. The concentration of fluoride causing 50% inhibition (IC50) to acetoclastic ranged from 18.1 to 155.7 mg L-1 while for hydrogenotrophic methanogens was>400.0 mg L-1. The feasibility of a combined system consisting of anaerobic up-flow anaerobic sludge blanket (UASB) followed by aerobic activated sludge (AS) reactor for removal of carbonaceous and nitrogenous contaminants from strong synthetic sewage (2.5 g chemical oxygen demand (COD) L-1) was also studied. The average combined removal of total COD, volatile fatty acids (VFA) and protein was higher than 89.0%, 99.0% and 97.0%; respectively. Extensive nitrification (96.0%) was observed when dissolved oxygen (DO) concentration was>2.0 mg L-1. In contrast, only partial nitrification occurred when the AS received high organic loads and/or the DO level was below 2.0 mg L-1. The inhibitory effect of nitrite and nitrate on methanogenesis was evaluated. Methanogenic activity was inhibited by the presence of NOx- compounds (i.e., nitrite and nitrate). The inhibition imparted by nitrate was not due to the nitrate itself, but rather to its reduced intermediate, nitrite. The toxicity of NOx- to methanogens was found to be reversible after all the NOx- were reduced during denitrification. Moreover, the development of Anammox enrichment cultures was evaluated. Anammox cultures were successfully developed using sludge samples collected from municipal wastewater treatment plants (WWTPs) as inocula but not from methanogenic granular sludges. Return activated sludge (RAS) collected from WWTP operating for biological nitrogen removal had the highest intrinsic level of Anammox activity. RAS Anammox culture was developed rapidly within 40 days with a doubling time of 6.8 days.

Book Microbial Electrochemical Technologies

Download or read book Microbial Electrochemical Technologies written by Sonia M. Tiquia-Arashiro and published by CRC Press. This book was released on 2020-01-06 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book encompasses the most updated and recent account of research and implementation of Microbial Electrochemical Technologies (METs) from pioneers and experienced researchers in the field who have been working on the interface between electrochemistry and microbiology/biotechnology for many years. It provides a holistic view of the METs, detailing the functional mechanisms, operational configurations, influencing factors governing the reaction process and integration strategies. The book not only provides historical perspectives of the technology and its evolution over the years but also the most recent examples of up-scaling and near future commercialization, making it a must-read for researchers, students, industry practitioners and science enthusiasts. Key Features: Introduces novel technologies that can impact the future infrastructure at the water-energy nexus. Outlines methodologies development and application of microbial electrochemical technologies and details out the illustrations of microbial and electrochemical concepts. Reviews applications across a wide variety of scales, from power generation in the laboratory to approaches. Discusses techniques such as molecular biology and mathematical modeling; the future development of this promising technology; and the role of the system components for the implementation of bioelectrochemical technologies for practical utility. Explores key challenges for implementing these systems and compares them to similar renewable energy technologies, including their efficiency, scalability, system lifetimes, and reliability.

Book Biological Wastewater Treatment

Download or read book Biological Wastewater Treatment written by C. P. Leslie Grady Jr. and published by CRC Press. This book was released on 2011-05-09 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following in the footsteps of previous highly successful and useful editions, Biological Wastewater Treatment, Third Edition presents the theoretical principles and design procedures for biochemical operations used in wastewater treatment processes. It reflects important changes and advancements in the field, such as a revised treatment of the micr