Download or read book Transport of Pollutants Through Porous Media Facilitated by Colloids written by R. A. van der Toorn and published by . This book was released on 1995 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloidal Transport in Porous Media written by Fritz H. Frimmel and published by Springer Science & Business Media. This book was released on 2007-05-26 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the basics of abiotic colloid characterization, of biocolloids and biofilms, the resulting transport phenomena and their engineering aspects. The contributors comprise an international group of leading specialists devoted to colloidal sciences. The contributions include theoretical considerations, results from model experiments, and field studies. The information provided here will benefit students and scientists interested in the analytical, chemical, microbiological, geological and hydrological aspects of material transport in aquatic systems and soils.
Download or read book Colloid facilitated Transport of Contaminants in Porous Media written by Sujoy B. Roy and published by . This book was released on 1995 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloid and Contaminant Co transport in Fractured Porous Media written by Tanya Kay Bilezikjian and published by . This book was released on 2001 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling of Colloid Facilitated Contaminant Transport in Unsaturated Porous Media written by Heecheul Choi and published by . This book was released on 1995 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantitative Multi spectral Light transmission Imaging of Colloid Transport in Porous Media at the Meso Scale written by Erika Lorna Kraft and published by . This book was released on 2011 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloids, particles smaller than ten microns in diameter, are ubiquitous in the subsurface. Colloids have an effect on the transport of contaminants that bind to their surfaces, and can reduce the permeability of aquifer materials through deposition. Some microorganisms, including pathogens, are also transported in the subsurface as colloids. The study of colloid transport behavior is important to the improvement of contaminant transport predictions, and thus to the protection of water quality. Imaging technologies provide detailed spatial-temporal concentration data not obtainable by traditional methods, which rely on the collection and analysis of water samples at discrete locations. A quantitative, light-transmission imaging system was developed for the observation of solute and colloid transport in a chamber containing porous media. Multi-spectral LEDs and high-quality optical filters were used with a sensitive charge-coupled device camera to obtain images of a 47x57cm sand pack containing two fluorescent tracers--disodium fluorescein and red-fluorescent latex colloids. The properties of the optical components, and the selection of tracers, were optimized to allow for collection of data on three distinct properties of the system in time and space--water content, fluorescein concentration, and colloid concentration. An image processing technique was developed to normalize collected images and to remove noise. The system was calibrated through comparison of processed intensities with known fluorescein and colloid concentrations. Quantification was possible over the concentration range 10-2 to 102ppm for fluorescein, and 10-1 to 103ppm for colloids. This wide range of detection and the very low detection limits were made possible by the improvement in the signal-to-noise ratio that resulted from system development. Experiments were conducted to demonstrate the utility of this method to observe and quantify fluorescein and colloid transport. Model predictions compared favorably with collected data over multiple data sets, each containing approximately 300 data points. Colloid transport was reasonably fit by the advection-dispersion equation using a retardation factor and a first-order deposition coefficient to represent colloid interactions with the sand surface. In some cases, accurate description of colloid transport will require a more detailed parameterization of colloid dynamics that was beyond the scope of this work. Data presented in this thesis however demonstrate the power of this system to provide insight into the fate and transport of fluorescein and colloids in porous media. These insights facilitate prevention of groundwater pollution by colloidal contaminants, and contribute to effective design of remediation strategies for colloid-contaminated environments.
Download or read book Manipulation of Groundwater Colloids for Environmental Restoration written by John McCarthy and published by CRC Press. This book was released on 1993-01-04 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This valuable resource discusses several strategies of manipulating colloids for environmental restoration, identifies advantages and disadvantages of each strategy, and considers obstacles limiting the application of each strategy. Approaches evaluated include the following: Chemical modification of subsurface systems to mobilize or deposit colloids in situ Altering the mobility of microorganisms to improve delivery of microbes for bioremediation Manipulating colloids or biocolloids (bacteria) to change aquifer permeability to either enhance bioremediation or create in situ barriers Introducing modified colloids, surfactants, and emulsions to control colloid mobility or to increase recovery of sorbed contaminants by pump and treat methods Manipulation of Groundwater Colloids for Environmental Restoration also contains short, focused research reports on specific studies relevant to the various approaches under consideration. Subjects covered range from mobility of organic macromolecules by controlled field injection experiments to new techniques that investigate surface chemistry and aggregation of inorganic colloids. Other topics discussed include the depositional behavior and transport of biocolloids in porous media, surfactants as modifiers of surface binding sites on colloids, and genetic engineering of microorganisms to serve as contaminant-scavenging biocolloids. Manipulation of Groundwater Colloids for Environmental Restoration is an excellent resource for research scientists in hydrology, chemistry, and microbiology; environmental consultants; regulators; environmental engineers; bioremediation microbiologists; and engineers.
Download or read book Effects of Water Content and Soil Structure on Colloid Transport in Porous Media written by Marlene Ullum and published by . This book was released on 2001 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contaminant Transport in Porous Media in the Presence of Colloids written by Hesham Bekhit Mohamed Bekhit and published by . This book was released on 2004 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloidal Transport in Porous Media written by Fritz H. Frimmel and published by Springer Verlag. This book was released on 2007-05-29 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloids are known to be the often neglected phase for the transport of pollutants in aquatic ecosystems. This book covers the basics of abiotic colloid characterization, of biocolloids and biofilms, the resulting transport phenomena and their engineering aspects. The contributors are leading specialists devoted to colloidal sciences. The discussion reflects their broad scope of viewpoint and depth of expertise. Coverage includes theoretical considerations, results from model experiments, and field studies.
Download or read book Colloid and Colloid assisted Transport of Contaminants in Porous Media written by K. U. Totsche and published by . This book was released on 1998 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloid Transport and Attenuation in Saturated Porous Media written by Xinyao Yang and published by LAP Lambert Academic Publishing. This book was released on 2012 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloids refer to particles or macromolecules with at least one dimension of 1nm 1m. A wide range of environmental particles fall within this category including microorganisms, nanoparticles, and mineral precipitates. Understanding colloid fate and transport in porous medium not only permits more effective protection of water supplies, but also allows for the development of more effective pollutant remediation strategies. Organic matter (OM) complicates colloid behaviour. To date the influence of OM on colloid mobility in porous media has been largely qualitative. This book presents research leading to the development of multiple-pulse column techniques that may be integrated with mathematical models to quantify the effects of OM on particulate colloid attenuation in saturated porous medium. Research has investigated how two groups of environmental organic compounds, humic acids and proteins, influence particulate colloid attenuation by saturated sand. Study findings may shed light on complex colloidal behaviour in organic matter impacted environment and be useful to professionals in contaminant hydrogeology, environmental remediation, and wastewater treatment.
Download or read book Computational Fluid Flow and Transport of Colloidal Particles in Soil Pores written by Mehmet Ekrem Cakmak and published by . This book was released on 2011 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transport of colloidal size particulate matter is of special interest of environmental studies because colloids and adsorbed chemicals can be transported over long distances. Colloid facilitated transport can pose potentially high risk for pollution of ground water. Visualizations of colloid transport using bright field and confocal microscopes have discovered interesting phenomena such colloids moving in circles that cannot be described by the traditional Darcy scale models. That is why computational pore scale models are needed to better understand colloid transport and fate in porous media. Transport and fate of colloids depend largely on flow field in the pores and it is, therefore, important to simulate the flow field while taking grain surface properties into account. The aim of this dissertation is hence to determine the flow fields in realistic pores by solving the incompressible Navier-Stokes equation with a powerful commercial available finite element program COMSOL Multiphysics. The dissertation has five chapters. In the first chapter a short introduction is given. In the second chapter the COMSOL Multiphysics program is tested by revisiting the classical colloid filtration theory on colloid retention on a spherical sand grain. Retention of colloids on grains simulated with COMSOL is found to be similar to semi-analytical solutions previously published. Subsequently colloid retention on an air bubble is simulated and greater colloid retention is calculated than on a soil grain due to the slip boundary condition at the Air-Water interface which creates higher velocities and more fluid flow around air bubble resulting in greater amounts of colloids that can diffuse to the interface. In the third chapter the effect of surface roughness on hydrodynamics of colloid transport in a saturated porous media is investigated by simulating the flow fields around perfectly smooth, smoothed, and naturally rough sand grains. The results show that micron scale surface asperities of rough grains create greater vorticity and more stagnant flow regions compared to smooth grains likely resulting in greater colloid retention for the rough grains. In the fourth chapter the dependence of dynamic contact angle between the interface of two immiscible fluids and solid surface on the interface velocity is simulated in an empty capillary channel to provide a new understanding on the formation of unstable wetting fronts in coarse or water repellent soils. The results show an increase in contact angle when the velocity of the front increases, which is consistent with experimental studies in the literature. In the fifth chapter the problems encountered during the research and future directions are briefly explained.
Download or read book The Role of Colloidal Systems in Environmental Protection written by Monzer Fanun and published by Elsevier. This book was released on 2014-02-08 with total page 715 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Role of Colloidal Systems in Environmental Protection describes the importance of colloids in many applications that contribute to environmental protection, including drinking water and wastewater treatment, heavy metal remediation, treatment of radioactive materials, corrosion, and energy conversion. Knowledge of the physical and chemical composition of colloids is important to understand and accurately model the relevant processes. The book familiarizes the reader with the technological features of the application of colloids in environmental protection, and provides chemical engineers, researchers, and scientists in academic and corporate communities with the latest developments in this field. Each chapter covers the whole spectrum of the relevant science, from the fundamentals to applications. Provides the applied technological features of colloids in environmental protection Gives insight into the use of bio-solid colloids as contaminant carriers Covers the natural occurrence of biosurfactants in the environment and their applications Provides information on the use of nanoparticles for environmental applications Chapters written by recognized and respected experts in the field from all over the world
Download or read book Modelling of Pollutants in Complex Environmental Systems written by Grady Hanrahan and published by ILM Publications. This book was released on 2010 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental modelling has enjoyed a long tradition, but there is a defined need to continually address both the power and the limitations of such models, as well as their quantitative assessment. This book showcases modern environmental modelling methods, the basic theory behind them and their incorporation into complex environmental investigations. It highlights advanced computing technologies and how they have led to unprecedented and adaptive modelling, simulation and decision-support tools to study complex environmental systems, and how they can be applied to current environmental concerns. This volume is essential reading for researchers in academia, industry and government-related bodies who have a vested interest in all aspects of environmental modelling. Features include: A range of modern environmental modelling techniques are described by experts from around the world, including the USA, Canada, Australia, Europe and Thailand; many examples from air, water, soil/sediment and biological matrices are covered in detail throughout the book; key chapters are included on modelling uncertainty and sensitivity analysis; and, a selection of figures are provided in full colour to enable greater comprehension of the topics discussed.
Download or read book The Role of Inorganic Colloidal Particles in Transport of Contaminants Through Porous Media written by Mbangiseni Patrick Nepfumbada and published by . This book was released on 1995 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Colloid Facilitated Groundwater Contaminant Transport written by Shiyan Jiang and published by . This book was released on 1993 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
