This first release shows how to use Jupyter notebooks to compute solutions to the 1-D advection-d... more This first release shows how to use Jupyter notebooks to compute solutions to the 1-D advection-dispersion equation in a column.
This release was current at the time of writing of the manuscript "An Automated Approach for... more This release was current at the time of writing of the manuscript "An Automated Approach for Construction of Long-Term, Data-Intensive Watershed Models" that is to be published in the Journal of Computing in Civil Engineering.
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management, 2007
Recent studies have demonstrated that fully fluorinated surfactant molecules have a tendency to a... more Recent studies have demonstrated that fully fluorinated surfactant molecules have a tendency to accumulate in biological tissues. As a result, the Environmental Protection Agency has sought to reduce the usage of these chemicals and limit their discharge into the environment. Perfluorooctanoic acid (PFOA) is used in the manufacture of fluoropolymers and fluoroelastomers and is present as a component of some top-antireflective coating (TARC) materials. Perfluorooctane sulfonate (PFOS) is a component of some TARCs and photoacid generators used by the semiconductor industry in its fabrication processes. The purpose of this study is to determine effective and economically feasible methods to treat PFOA/PFOS contaminated process wastewater. A treatment screening study was performed investigating activated carbon adsorption, adsorption onto calcium fluoride solids, evaporation, ion exchange, and liquid-liquid extraction. Ion exchange was determined to be the best technology for treatment of PFOA/PFOS wastewater...
The fate and transport of dissolved constituents in porous media has important applications in th... more The fate and transport of dissolved constituents in porous media has important applications in the earth and environmental sciences and many engineering disciplines. Mathematical models are commonly applied to simulate the movement of substances in porous media using the advection-dispersion equation. Whereas computer programs based on numerical solutions are commonly employed to solve the governing equations for these problems, analytical solutions also exist for some important one-dimensional cases. These solutions are often still quite complex to apply in practice, and therefore computational tools are still needed to apply them to determine the concentrations of dissolved substances as a function of space and time. The Python Programming Language provides a variety of tools that enable implementation of analytical solutions into useful tools and facilitate their application to experimental data. Python provides an important but underutilized tool in environmental modeling courses. This article highlights the development of a series of Python-based computing tools that can be used to numerically compute the values of an analytical solution to the onedimensional advection-dispersion equation. These tools are targeted to graduate and advanced undergraduate courses that teach environmental modeling and the application of Python for computing.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Iranian Journal of Science and Technology-Transactions of Civil Engineering, Mar 20, 2020
Scouring around spur dikes, which are popular guide bank structures, is a major concern for hydra... more Scouring around spur dikes, which are popular guide bank structures, is a major concern for hydraulic engineers. Collars are protective palates which are used to reduce the local scouring. Employing an effective collar needs the adjustment of several factors such as shape, area and installation elevation. However, investigating all these factors and their combinations is often neither economical nor feasible. One appropriate approach to overcome these problems is to conduct these experiments based on fractional factorial designs such as the Taguchi method. Therefore, the main objective of the present study is to investigate the effects of different shapes, sizes and installation elevations of the collar to reduce scour around straight and angled spur dikes using the Taguchi method. In the first part of this paper, experimental data were collected based on a Taguchi mixed experiment design (L 18). Then, using Taguchi analysis, the optimal condition for collar efficiency was obtained. In addition, analysis of variances confirmed that the collar elevation, collar area and spur dike angle factors had significant impacts on the scouring depth reduction, while the collar shape proved to be an insignificant factor. In the second part, the validation tests revealed that the Taguchi method achieved high prediction accuracy in the experiments. In the last part, the variation of flow intensity was investigated and the experimental results indicated that by increasing the flow intensity, the collar performance was reduced accordingly.
Supply chains for transportation fuels were analyzed using an extensive system boundary to gain i... more Supply chains for transportation fuels were analyzed using an extensive system boundary to gain insights into the connections between transportation energy and water resource consumption.
Journal of Computing in Civil Engineering, Jul 1, 2018
AbstractWatershed models such as the Hydrological Simulation Program in FORTRAN (HSPF) are freque... more AbstractWatershed models such as the Hydrological Simulation Program in FORTRAN (HSPF) are frequently used to analyze large-scale water quantity and water quality issues. The construction of HSPF m...
The production of all forms of energy consumes water. To meet increased energy demands, it is ess... more The production of all forms of energy consumes water. To meet increased energy demands, it is essential to quantify the amount of water consumed in the production of different forms of energy. By analyzing the water consumed in different technologies, it is possible to identify areas for improvement in water conservation and reduce water stress in energy-producing regions.
World Environmental and Water Resources Congress 2020
This study develops a treatment strategy for produced water. This kind of water can include forma... more This study develops a treatment strategy for produced water. This kind of water can include formation water, injection water, and any chemicals added downhole or within the separation process. Regardless of the parameters, produced water contains several kinds of components such as heavy metals, salts, radionuclides, oil and grease, suspended solids, dissolved solids, and other dissolved and volatile organic compounds. To manage this highly polluted water, several strategies can be considered; one of these strategies is produced water reuse that makes this kind of water as an acceptable resource for industries, irrigations, and livestock instead of a waste stream. The main goal of this study is to prepare produced water for reuse methods by removing the major contaminant which is salt (ionic compounds). During these experiments, the specific species causing membrane fouling and the approaches to reduce the fouling process will be determined.
This first release shows how to use Jupyter notebooks to compute solutions to the 1-D advection-d... more This first release shows how to use Jupyter notebooks to compute solutions to the 1-D advection-dispersion equation in a column.
This release was current at the time of writing of the manuscript "An Automated Approach for... more This release was current at the time of writing of the manuscript "An Automated Approach for Construction of Long-Term, Data-Intensive Watershed Models" that is to be published in the Journal of Computing in Civil Engineering.
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management, 2007
Recent studies have demonstrated that fully fluorinated surfactant molecules have a tendency to a... more Recent studies have demonstrated that fully fluorinated surfactant molecules have a tendency to accumulate in biological tissues. As a result, the Environmental Protection Agency has sought to reduce the usage of these chemicals and limit their discharge into the environment. Perfluorooctanoic acid (PFOA) is used in the manufacture of fluoropolymers and fluoroelastomers and is present as a component of some top-antireflective coating (TARC) materials. Perfluorooctane sulfonate (PFOS) is a component of some TARCs and photoacid generators used by the semiconductor industry in its fabrication processes. The purpose of this study is to determine effective and economically feasible methods to treat PFOA/PFOS contaminated process wastewater. A treatment screening study was performed investigating activated carbon adsorption, adsorption onto calcium fluoride solids, evaporation, ion exchange, and liquid-liquid extraction. Ion exchange was determined to be the best technology for treatment of PFOA/PFOS wastewater...
The fate and transport of dissolved constituents in porous media has important applications in th... more The fate and transport of dissolved constituents in porous media has important applications in the earth and environmental sciences and many engineering disciplines. Mathematical models are commonly applied to simulate the movement of substances in porous media using the advection-dispersion equation. Whereas computer programs based on numerical solutions are commonly employed to solve the governing equations for these problems, analytical solutions also exist for some important one-dimensional cases. These solutions are often still quite complex to apply in practice, and therefore computational tools are still needed to apply them to determine the concentrations of dissolved substances as a function of space and time. The Python Programming Language provides a variety of tools that enable implementation of analytical solutions into useful tools and facilitate their application to experimental data. Python provides an important but underutilized tool in environmental modeling courses. This article highlights the development of a series of Python-based computing tools that can be used to numerically compute the values of an analytical solution to the onedimensional advection-dispersion equation. These tools are targeted to graduate and advanced undergraduate courses that teach environmental modeling and the application of Python for computing.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Iranian Journal of Science and Technology-Transactions of Civil Engineering, Mar 20, 2020
Scouring around spur dikes, which are popular guide bank structures, is a major concern for hydra... more Scouring around spur dikes, which are popular guide bank structures, is a major concern for hydraulic engineers. Collars are protective palates which are used to reduce the local scouring. Employing an effective collar needs the adjustment of several factors such as shape, area and installation elevation. However, investigating all these factors and their combinations is often neither economical nor feasible. One appropriate approach to overcome these problems is to conduct these experiments based on fractional factorial designs such as the Taguchi method. Therefore, the main objective of the present study is to investigate the effects of different shapes, sizes and installation elevations of the collar to reduce scour around straight and angled spur dikes using the Taguchi method. In the first part of this paper, experimental data were collected based on a Taguchi mixed experiment design (L 18). Then, using Taguchi analysis, the optimal condition for collar efficiency was obtained. In addition, analysis of variances confirmed that the collar elevation, collar area and spur dike angle factors had significant impacts on the scouring depth reduction, while the collar shape proved to be an insignificant factor. In the second part, the validation tests revealed that the Taguchi method achieved high prediction accuracy in the experiments. In the last part, the variation of flow intensity was investigated and the experimental results indicated that by increasing the flow intensity, the collar performance was reduced accordingly.
Supply chains for transportation fuels were analyzed using an extensive system boundary to gain i... more Supply chains for transportation fuels were analyzed using an extensive system boundary to gain insights into the connections between transportation energy and water resource consumption.
Journal of Computing in Civil Engineering, Jul 1, 2018
AbstractWatershed models such as the Hydrological Simulation Program in FORTRAN (HSPF) are freque... more AbstractWatershed models such as the Hydrological Simulation Program in FORTRAN (HSPF) are frequently used to analyze large-scale water quantity and water quality issues. The construction of HSPF m...
The production of all forms of energy consumes water. To meet increased energy demands, it is ess... more The production of all forms of energy consumes water. To meet increased energy demands, it is essential to quantify the amount of water consumed in the production of different forms of energy. By analyzing the water consumed in different technologies, it is possible to identify areas for improvement in water conservation and reduce water stress in energy-producing regions.
World Environmental and Water Resources Congress 2020
This study develops a treatment strategy for produced water. This kind of water can include forma... more This study develops a treatment strategy for produced water. This kind of water can include formation water, injection water, and any chemicals added downhole or within the separation process. Regardless of the parameters, produced water contains several kinds of components such as heavy metals, salts, radionuclides, oil and grease, suspended solids, dissolved solids, and other dissolved and volatile organic compounds. To manage this highly polluted water, several strategies can be considered; one of these strategies is produced water reuse that makes this kind of water as an acceptable resource for industries, irrigations, and livestock instead of a waste stream. The main goal of this study is to prepare produced water for reuse methods by removing the major contaminant which is salt (ionic compounds). During these experiments, the specific species causing membrane fouling and the approaches to reduce the fouling process will be determined.
The historical release of contaminants into the environment has generated a legacy of contaminate... more The historical release of contaminants into the environment has generated a legacy of contaminated sites throughout the world. For years, the sediments in water bodies adjoining these pollution sources served as sinks for contaminants, particularly hydrophobic organic compounds (HOCs) and heavy metals. Many of these original sources have been eliminated, but the sediments that formerly served as a pollutant sink now serve as sources of contamination and residual environmental risk. Assessment and remediation of these contaminated sediment sites have been the subject of much scientific analysis, public debate and technological innovation (NRC, 2001). There are few economically viable options for management of contaminated sediments. Capping sediments with a layer of clean material is one of few alternatives with a proven record of success for sediment remediation. Capping is designed to achieve one or more of the following objectives depending upon the cause of exposure and risk at a site: 1. Contain contaminated sediments to eliminate sediment re-suspension risk 2. Contain contaminants in sediments and reduce migration and release 3. Separate a benthic community from interacting with and processing the underlying contaminated sediments The first objective is achieved by designing a cap that is sufficiently armored to reduce or eliminate erosion of the underlying sediment and is most effective when contaminants are strongly solid associated as is typically the case. The sorption characteristics of such a cap are largely irrelevant since it is designed to only contain the underlying sediments and sand; gravel and/or stone are typically used in such cases. The second objective is often also achieved by this type of cap although in some instances, such as when there is significant groundwater upwelling through the cap, an alternative cap material might be chosen. This alternative or amended cap might be chosen to control upwelling (low permeability cap), to absorb or sequester contaminants (sorptive caps) or encourage degradation and fate processes of the contaminants (reactive caps). The final objective is a particularly important advantage of a cap in that the interaction of a benthic community with the contaminated sediments leads to particularly rapid contaminant transport (through bioturbation) and can lead to bioaccumulation and trophic transfer of the contaminants. The separation of the benthic community from the contaminated sediments reduces or eliminates contaminant exposure by either of these mechanisms. Capping contaminated sediments following dredging operations and for capping dredged material has been a common practice by the U.S. Army Corps of Engineers since the 1970s (Bokuniewicz and Liu, 1981; O'Connor and O'Connor, 1982). Some field studies were performed on the long-term effects of caps on contaminant levels at these sites (Fredette et
Uploads
Papers by David Lampert