Download or read book CFD Study of Full Scale Aerobic Bioreactors Evaluation of Dynamic O2 Distribution Gas Liquid Mass Transfer and Reaction written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: If advanced biofuels are to measurably displace fossil fuels in the near term, they will have to operate at levels of scale, efficiency, and margin unprecedented in the current biotech industry. For aerobically-grown products in particular, scale-up is complex and the practical size, cost, and operability of extremely large reactors is not well understood. Put simply, the problem of how to attain fuel-class production scales comes down to cost-effective delivery of oxygen at high mass transfer rates and low capital and operating costs. To that end, very large reactor vessels (>500 m3) are proposed in order to achieve favorable economies of scale. Additionally, techno-economic evaluation indicates that bubble-column reactors are more cost-effective than stirred-tank reactors in many low-viscosity cultures. In order to advance the design of extremely large aerobic bioreactors, we have performed computational fluid dynamics (CFD) simulations of bubble-column reactors. A multiphase Euler-Euler model is used to explicitly account for the spatial distribution of air (i.e., gas bubbles) in the reactor. Expanding on the existing bioreactor CFD literature (typically focused on the hydrodynamics of bubbly flows), our simulations include interphase mass transfer of oxygen and a simple phenomenological reaction representing the uptake and consumption of dissolved oxygen by submerged cells. The simulations reproduce the expected flow profiles, with net upward flow in the center of column and downward flow near the wall. At high simulated oxygen uptake rates (OUR), oxygen-depleted regions can be observed in the reactor. By increasing the gas flow to enhance mixing and eliminate depleted areas, a maximum oxygen transfer (OTR) rate is obtained as a function of superficial velocity. These insights regarding minimum superficial velocity and maximum reactor size are incorporated into NREL's larger techno-economic models to supplement standard reactor design equations.

Download or read book CFD Study of Full Scale Aerobic Bioreactors written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: If advanced biofuels are to measurably displace fossil fuels in the near term, they will have to operate at levels of scale, efficiency, and margin unprecedented in the current biotech industry. For aerobically-grown products in particular, scale-up is complex and the practical size, cost, and operability of extremely large reactors is not well understood. Put simply, the problem of how to attain fuel-class production scales comes down to cost-effective delivery of oxygen at high mass transfer rates and low capital and operating costs. To that end, very large reactor vessels (>500 m3) are proposed in order to achieve favorable economies of scale. Additionally, techno-economic evaluation indicates that bubble-column reactors are more cost-effective than stirred-tank reactors in many low-viscosity cultures. In order to advance the design of extremely large aerobic bioreactors, we have performed computational fluid dynamics (CFD) simulations of bubble-column reactors. A multiphase Euler-Euler model is used to explicitly account for the spatial distribution of air (i.e., gas bubbles) in the reactor. Expanding on the existing bioreactor CFD literature (typically focused on the hydrodynamics of bubbly flows), our simulations include interphase mass transfer of oxygen and a simple phenomenological reaction representing the uptake and consumption of dissolved oxygen by submerged cells. The simulations reproduce the expected flow profiles, with net upward flow in the center of column and downward flow near the wall. At high simulated oxygen uptake rates (OUR), oxygen-depleted regions can be observed in the reactor. By increasing the gas flow to enhance mixing and eliminate depleted areas, a maximum oxygen transfer (OTR) rate is obtained as a function of superficial velocity. These insights regarding minimum superficial velocity and maximum reactor size are incorporated into NREL's larger techno-economic models to supplement standard reactor design equations.

Download or read book Multiphase Reacting Flow Simulations and Optimization of Commercial scale Aerobic Bioreactors written by Hariswaran Sitaraman and published by . This book was released on 2020 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book 32nd European Symposium on Computer Aided Process Engineering written by Ludovic Montastruc and published by Elsevier. This book was released on 2022-06-30 with total page 1760 pages. Available in PDF, EPUB and Kindle. Book excerpt: 32nd European Symposium on Computer Aided Process Engineering: ESCAPE-32 contains the papers presented at the 32nd European Symposium of Computer Aided Process Engineering (ESCAPE) event held in Toulouse, France. It is a valuable resource for chemical engineers, chemical process engineers, researchers in industry and academia, students and consultants for chemical industries who work in process development and design. - Presents findings and discussions from the 32nd European Symposium of Computer Aided Process Engineering (ESCAPE) event

Download or read book CFD Modelling for Wastewater Treatment Processes written by Julien Laurent and published by IWA Publishing. This book was released on 2022-06-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Scientific and Technical Report (STR) provides in-depth fundamentals and guidelines regarding Computational Fluid Dynamics (CFD) simulations of Water Resources Recovery Facilities (WRRFs) unit processes (e.g. headworks, aerobic and anaerobic biological reactors, settling tanks, disinfection). Each unit process is described with respect to: Literature review and process description Relevant CFD concepts and modelling approach Case studies Future research needs CFD Modelling for Wastewater Treatment Processes also opens the discussion on two fundamental topics: experimental validation of CFD simulations, and the complementarity between CFD and Chemical Reaction Engineering approaches. This book is intended for undergraduate and graduate students majoring in fields related to wastewater treatment and/or fluid mechanics, as well as researchers and engineers who conduct research and practices in modelling such unit processes. Water resource recovery modelling is not just about lab-scale processes. Now and in the future, it is about improving our understanding of (and designing better) full-scale facilities!

Download or read book Coupled Microbial conversion and Computational fluid dynamics CFD Models for Butanediol Production in Micro aerated Reactors written by Hariswaran Sitaraman and published by . This book was released on 2020 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and CFD Study on Scale up of Gas liquid Stirred Tank Bioreactor written by Sook Fun Pang and published by . This book was released on 2010 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gas Liquid Flow Modeling for Renewable Fuels Production written by and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerobic/anaerobic and gas fermentation pathways have emerged as promising new technologies for the generation of renewable fuels/chemicals from biomass derived sugars, and mixtures of greenhouse/energy rich gas streams (CO2/CH4/H2/CO) via microbial action. Example pathways include sugars-to-ethanol conversion, biomethanation (CO2/H2 to CH4), biogas upgrading, CO fermentation and wet-waste conversion. Gas and liquid phase transport, mass-transfer, and mixing physics at large length scales can significantly affect microbial conversion rates, particularly when the microbial reaction requires a narrow set of conditions. These phenomena are difficult to study in small-scale bench-top reactors that are typically well-mixed. Predictive computational fluid dynamics (CFD) based simulations can therefore aid in the scale-up, design and optimization of these reactors. This work presents multiphase Euler-Euler CFD simulations of at-scale (~500 m3) bioreactors. Our mathematical model treats the gas and liquid as interpenetrating phases. This approach reduces the computational complexity of tracking individual gas bubbles that are several orders of magnitude smaller than reactor dimensions. We solve the Reynolds averaged Navier-Stokes (RANS) multiphase equations that account for phase and chemical species transport, interphase mass and momentum transfer and uses a phenomenological model for gas uptake by microbes. We use a customized solver derived from open-source CFD toolbox, OpenFOAM [1], to perform these simulations, which has been validated against small-scale reactors in our previous work [2]. There is currently a knowledge-gap regarding bubble-size distributions when using gas mixtures with vastly different properties, which can have a significant impact overall mass-transfer. For example, hydrogen bubbles are more buoyant compared to other relatively heavier gases (CO2/CH4/CO), resulting in a large distribution of residence times and bubble sizes. This work therefore develops a deeper understanding of bubble dynamics and interphase mass transfer in such heterogenous gas mixtures through well-resolved computational models. We use a population balance model (PBM) for bubble-size-distribution modeling that is validated against small-scale experiments in our solver with an uncertainty quantification study for bubble coalescence and break-up model parameters. Results pertaining to multiple simulations of gas-fermentation reactors are presented where gas mixtures with varying compositions of CO2/CH4/CO/H2 are imposed at the sparger boundaries. The spatio-temporal variations in bubble-size distribution and mass transfer coefficient are analyzed for varying superficial velocities and gas-compositions for varying sizes of bubble-column and airlift reactors. This work will also examine the performance of different reactor designs, viz. bubble column reactor, airlift reactor with an internal draft tube, and a stirred-tank reactor with Rushton impellers. Reactor mass-transfer coefficient, gas hold-up, and dissolved gas distribution are critically analyzed among reactors, and sensitivity studies pertaining to gas flow rates and reactor geometry will be presented. [1] Weller, H., Tabor, G., Jasak, H. and Fureby, C., A tensorial approach to computational continuum mechanics using object-oriented techniques, Computers in physics, 12, 6, 620--631, 1998. [2] Rahimi, M., Sitaraman, H., Humbird, D. and Stickel, J., Computational fluid dynamics study of full-scale aerobic bioreactors: Evaluation of gas-liquid mass transfer, oxygen uptake, and dynamic oxygen distribution, Chemical Engineering Research and Design, 139: 283-295.

Download or read book Handbook of Fluidization and Fluid Particle Systems written by Wen-Ching Yang and published by CRC Press. This book was released on 2003-03-19 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reference details particle characterization, dynamics, manufacturing, handling, and processing for the employment of multiphase reactors, as well as procedures in reactor scale-up and design for applications in the chemical, mineral, petroleum, power, cement and pharmaceuticals industries. The authors discuss flow through fixed beds, elutriation and entrainment, gas distributor and plenum design in fluidized beds, effect of internal tubes and baffles, general approaches to reactor design, applications for gasifiers and combustors, dilute phase pneumatic conveying, and applications for chemical production and processing. This is a valuable guide for chemists and engineers to use in their day-to-day work.

Download or read book Membrane Biological Reactors Theory Modeling Design Management and Applications to Wastewater Reuse Second Edition written by Faisal I. Hai and published by IWA Publishing. This book was released on 2018-10-15 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MBR market continues to experience a massive growth. The best practice in the field is constantly changing and unique quality requirements and management issues are regularly emerging. The second edition of Membrane Biological Reactors: Theory, Modeling, Design, Management and Applications to Wastewater Reuse comprehensively covers the salient features and emerging issues associated with the MBR technology. The book provides thorough coverage starting from biological aspects and fundamentals of membranes, via modeling and design concepts, to practitioners’ perspective and good application examples. In the second edition, the chapters have been updated to cover the recently emerged issues. Particularly, the book presents the current status of the technology including market drivers/ restraints and development trend. Process fundamentals (both the biological and membrane components) have received in-depth coverage in the new edition. A new chapter has been added to provide a stronger focus on reuse applications in general and the decisive role of MBR in the entire reuse chain. The second edition also comes with a new chapter containing practical design problems to complement the concepts communicated throughout the book. Other distinguishing features of the new edition are coverage of novel developments and hybrid processes for specialised wastewaters, energy efficiency and sustainability of the process, aspects of MBR process automation and recent material on case studies. The new edition is a valuable reference to the academic and professional community and suitable for undergraduate and postgraduate teaching in Environmental Engineering, Chemical Engineering and Biotechnology.

Download or read book A Complete Guidebook on Biofilm Study written by Dijendra N. Roy and published by Academic Press. This book was released on 2022-06-22 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Complete Guidebook on Biofilm Study has emphasized the biofilm-related issues in the present context related to research and development. For this purpose, experimental design and relevant experimental protocols for the biofilm studies have been highlighted here. In addition to that, inhibitors from natural or synthetic sources against microbial biofilm development have been addressed. This approach has been further substantiated by bioinformatics as well as nanotechnology-based reports. Both, the image processing related to biofilm study and the characters of substratum associated with biofilm development have also been included for a better understanding of the beginners in this field. Further, how biofilm helps and/or hampers in food processing and waste management system, that discussion has been considered in this book. Similarly, human benefits from biofilm and reverse of it have also been included considering host-pathogen interaction, immunity aspects, and others. - Carrying huge resources/information/ideas in a compiled manner for biofilm study/work - Has highlighted how biofilm-related experiment has to be designed based on protocols - This book has focused majorly about biofilm-related gene regulation along with the development of different inhibitors for therapeutic aspects. This paradigm has been further discussed based on the nanotechnology and bioinformatics approach - Biofilm studies related to waste management, food processing, and image processing, which are newly upcoming have been emphasized in this book

Download or read book Industrial Biotechnology written by Christoph Wittmann and published by John Wiley & Sons. This book was released on 2017-03-06 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: The latest volume in the Advanced Biotechnology series provides an overview of the main product classes and platform chemicals produced by biotechnological processes today, with applications in the food, healthcare and fine chemical industries. Alongside the production of drugs and flavors as well as amino acids, bio-based monomers and polymers and biofuels, basic insights are also given as to the biotechnological processes yielding such products and how large-scale production may be enabled and improved. Of interest to biotechnologists, bio and chemical engineers, as well as those working in the biotechnological, chemical, and food industries.

Download or read book Fermentation Processes Engineering in the Food Industry written by Carlos Ricardo Soccol and published by CRC Press. This book was released on 2013-03-27 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the advent of modern tools of molecular biology and genetic engineering and new skills in metabolic engineering and synthetic biology, fermentation technology for industrial applications has developed enormously in recent years. Reflecting these advances, Fermentation Processes Engineering in the Food Industry explores the state of the art of the engineering technology aspects of fermentation processes in diverse food sectors. The book describes the benefits of fermented foods in human health in both dairy and non-dairy products and beverages. It examines applications of microalgae in the food industry and explains the application of metabolic engineering in the production of fermented food ingredients. Exploring a host of important topics in engineering fermentation processes, the book covers topics such as: Methods and techniques for the isolation, improvement, and preservation of the microbial cultures used in the food fermentation industry The fundamentals of fermentation processes, modes of fermentation, and the principles of upstream operation Physical and chemicals factors that affect fermentation processes Different types of fermenters employed in submerged and solid-state fermentation Unitary operations for solid-liquid separation, concentration, and drying of fermented foods Instrumentation and control of industrial fermentation processes The final chapter discusses the potential application of a biorefinery concept to add value to food industry wastes and presents a case study describing an integrated project in which the concept was applied. An essential reference for all food sector professionals, this volume surveys critical trends in the food, beverage, and additive industry and explores the sustainability of these processes.

Download or read book Bioreactors written by Carl-Fredrik Mandenius and published by John Wiley & Sons. This book was released on 2016-02-16 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this expert handbook both the topics and contributors are selected so as to provide an authoritative view of possible applications for this new technology. The result is an up-to-date survey of current challenges and opportunities in the design and operation of bioreactors for high-value products in the biomedical and chemical industries. Combining theory and practice, the authors explain such leading-edge technologies as single-use bioreactors, bioreactor simulators, and soft sensor monitoring, and discuss novel applications, such as stem cell production, process development, and multi-product reactors, using case studies from academia as well as from industry. A final section addresses the latest trends, including culture media design and systems biotechnology, which are expected to have an increasing impact on bioreactor design. With its focus on cutting-edge technologies and discussions of future developments, this handbook will remain an invaluable reference for many years to come.

Download or read book Membrane Biological Reactors written by Faisal I. Hai and published by IWA Publishing. This book was released on 2013-11-01 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years the MBR market has experienced unprecedented growth. The best practice in the field is constantly changing and unique quality requirements and management issues are regularly emerging. Membrane Biological Reactors: Theory, Modeling, Design, Management and Applications to Wastewater Reuse comprehensively covers the salient features and emerging issues associated with the MBR technology. The book provides thorough coverage starting from biological aspects and fundamentals of membranes, via modeling and design concepts, to practitioners’ perspective and good application examples. Membrane Biological Reactors focuses on all the relevant emerging issues raised by including the latest research from renowned experts in the field. It is a valuable reference to the academic and professional community and suitable for undergraduate and postgraduate teaching in Environmental Engineering, Chemical Engineering and Biotechnology. Editors: Faisal I. Hai, University of Wollongong, Australia Kazuo Yamamoto, University of Tokyo, Japan Chung-Hak Lee, Seoul National University, Korea.

Download or read book Wastewater Treatment and Reuse Technologies written by Faisal Ibney Hai and published by MDPI. This book was released on 2018-08-27 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Wastewater Treatment and Reuse Technologies" that was published in Applied Sciences