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The Metropolitan Water District of Southern California (Metropolitan), in conjunction with Koch Membrane Systems (KMS), evaluated three generations of a 16″-diameter by 60″-long reverse osmosis (RO) element in parallel with a commercially... more
The Metropolitan Water District of Southern California (Metropolitan), in conjunction with Koch Membrane Systems (KMS), evaluated three generations of a 16″-diameter by 60″-long reverse osmosis (RO) element in parallel with a commercially available 8″-diameter element. Design inefficiencies in the first-generation 16″ element resulted in a 20% lower specific flux when compared to an 8″ element. After making improvements in element
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Research Interests: Civil Engineering, Chemistry, Coal, Manganese, Coal Mining, and 4 moreSulfate, Chlorine, Alum, and Anthracite
ABSTRACT Inland desalination of brackish water can provide an important source of potable water in many parts of the world. Reverse osmosis (RO) and nanofiltration (NF) have become the technology of choice for many of these applications... more
ABSTRACT Inland desalination of brackish water can provide an important source of potable water in many parts of the world. Reverse osmosis (RO) and nanofiltration (NF) have become the technology of choice for many of these applications [T. Pankratz, The 19th IDA Worldwide Desalting Plant Inventory, Global Water Intelligence, Houston, TX, 2006]. However, large-scale deployment of RO/NF in inland locations would necessitate operation at relatively high product water recovery in order to maximize water resource utilization and minimize treatment costs and environmental challenges associated with disposal of the concentrate. Concentrate disposal is generally limited to one or two options for any given area and is directly related to land cost, energy costs, regulations, and the type and quantity of salts in the concentrate stream [M. Mickley, Concentrate management, in: M. Wilf (Ed.), The Guidebook to Membrane Desalination Technology: Reverese Osmosis, Nanofiltration and Hybrid Systems Process, Design, Applications and Economics, Balaban Desalination Publications, L'Aquila, Italy, 2007, p. 524; B. van der Bruggen, L. Lejon, C. Vandecasteele, Reuse, treatment, and discharge of the concentrate of pressure-driven membrane processes, Environ. Sci. Technol. 37 (2003) 3733–3738.]. Inland concentrate disposal options include reuse of concentrates, surface water discharge, sewer disposal, deep well injection, land applications, and evaporation ponds (followed by land filling of solids) [M. Mickley, Concentrate management, in: M. Wilf (Ed.), The Guidebook to Membrane Desalination Technology: Reverese Osmosis, Nanofiltration and Hybrid Systems Process, Design, Applications and Economics, Balaban Desalination Publications, L'Aquila, Italy, 2007, p. 524.]. This chapter provides an overview of post-RO/NF concentrate minimization technologies with the goal of minimizing the concentrate volume such that ultimate disposal options are more feasible. Examples of several of these technologies are also provided.
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ABSTRACT Parallel experiments using a blend of surface waters were conducted to evaluate differential fouling rates among reverse osmosis (RO) membranes when operated under pilot- vs. full-scale conditions. Testing was conducted using a... more
ABSTRACT Parallel experiments using a blend of surface waters were conducted to evaluate differential fouling rates among reverse osmosis (RO) membranes when operated under pilot- vs. full-scale conditions. Testing was conducted using a 230 L/min conventional (rapid mix/flocculation/sedimentation/filtration) package plant (CPP) and a 2,000 ML/d fullscale treatment plant (FTP) as pretreatment to separate RO membrane test units. Coagulation consisted of 10 mg/L alum (as Al2(SO4)3-14H2O) and 2.0 mg/L cationic polymer. A2.5-3.0 mg/L free-chlorine residual was maintained at the filter effluent and converted to chloramines through ammonium sulfate addition (3:1 chlorine-to-ammonia w/w ratio). Membrane performance was based on normalized flux and salt rejection data. Membrane surface analyses included scanning electron microscopy, energy-dispersive spectroscopy, and attenuated total reflectance Fourier transform infrared spectroscopy. Microbial activity and community analyses were conducted through (a) fluorescence staining with 4′,6′-diamidino-2-phenylindole, (b) polymerase-chain reaction amplification of isolated bacterial DNA, and (c) microscopic taxonomic identification. Results indicated that the RO membrane fed by the CPP fouled at least three times faster than the RO membrane fed by the FTP. The differential fouling between the two process streams was determined to be from lack of maintenance in the CPP influent piping that led to the establishment of biological communities consisting of algae, microbes, and, potentially, freshwater clams. These communities produced low levels of natural polymers, which when presented to the polyamide RO membrane surface, resulted in rapid fouling.
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... Each of three pretreatment scenarios produced effluent waters generally considered appropriate for use with RO [median turbidity of less than 0.1 Nephelometric turbidity unit (NTU) and mediansilt density index of less than 3]. Both... more
... Each of three pretreatment scenarios produced effluent waters generally considered appropriate for use with RO [median turbidity of less than 0.1 Nephelometric turbidity unit (NTU) and mediansilt density index of less than 3]. Both microfiltered and ozonated/ biofiltered waters ...
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was prepared as a result of work sponsored by the California Energy Commission (Commission). It does not necessarily represent the views of the Commission, its employees, or the State of California. The Commission, the State of... more
was prepared as a result of work sponsored by the California Energy Commission (Commission). It does not necessarily represent the views of the Commission, its employees, or the State of California. The Commission, the State of California, its employees, contractors, and subcontractors make no warranty, express or implied, and assume no legal liability for the information in this report; nor does any party represent that the use of this information will not infringe upon privately owned rights. This report has not been approved or disapproved by the Commission nor has the Commission passed upon the accuracy or adequacy of this information in this report. ii
A new technique has been developed to quickly monitor the changes in polarity of aqueous natural organic matter (NOM) using solid-phase extraction (SPE) cartridges. This paper introduces the NOM polarity rapid assessment method (PRAM).... more
A new technique has been developed to quickly monitor the changes in polarity of aqueous natural organic matter (NOM) using solid-phase extraction (SPE) cartridges. This paper introduces the NOM polarity rapid assessment method (PRAM). The PRAM technique characterizes changes in NOM polarity by monitoring the breakthrough curves from different SPE cartridges at UV254. The SPE cartridges used in this study include a wide range of polarity from non-polar C-18 materials to anion exchangers. Each individual cartridge run takes 10 minutes and requires about 15 ml of sample. The collected water sample matrix is not changed, i.e. all PRAM analyses were done under ambient conditions on the original sample. Polarity evaluation is completed without the sample being exposed to changes in sample conditions, such as pH, solvent extraction, sequential evaporations or freeze-drying. This technique was able to monitor the weekly changes in NOM polarity entering a water treatment plant and compares ...
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Research Interests: Civil Engineering, Chemistry, Coal, Manganese, Coal Mining, and 4 moreSulfate, Chlorine, Alum, and Anthracite
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Thesis (D. Env.)--University of California, Los Angeles, 2001. Vita. Includes bibliographical references.
ABSTRACT Parallel experiments using a blend of surface waters were conducted to evaluate differential fouling rates among reverse osmosis (RO) membranes when operated under pilot- vs. full-scale conditions. Testing was conducted using a... more
ABSTRACT Parallel experiments using a blend of surface waters were conducted to evaluate differential fouling rates among reverse osmosis (RO) membranes when operated under pilot- vs. full-scale conditions. Testing was conducted using a 230 L/min conventional (rapid mix/flocculation/sedimentation/filtration) package plant (CPP) and a 2,000 ML/d fullscale treatment plant (FTP) as pretreatment to separate RO membrane test units. Coagulation consisted of 10 mg/L alum (as Al2(SO4)3-14H2O) and 2.0 mg/L cationic polymer. A2.5-3.0 mg/L free-chlorine residual was maintained at the filter effluent and converted to chloramines through ammonium sulfate addition (3:1 chlorine-to-ammonia w/w ratio). Membrane performance was based on normalized flux and salt rejection data. Membrane surface analyses included scanning electron microscopy, energy-dispersive spectroscopy, and attenuated total reflectance Fourier transform infrared spectroscopy. Microbial activity and community analyses were conducted through (a) fluorescence staining with 4′,6′-diamidino-2-phenylindole, (b) polymerase-chain reaction amplification of isolated bacterial DNA, and (c) microscopic taxonomic identification. Results indicated that the RO membrane fed by the CPP fouled at least three times faster than the RO membrane fed by the FTP. The differential fouling between the two process streams was determined to be from lack of maintenance in the CPP influent piping that led to the establishment of biological communities consisting of algae, microbes, and, potentially, freshwater clams. These communities produced low levels of natural polymers, which when presented to the polyamide RO membrane surface, resulted in rapid fouling.
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ABSTRACT Inland desalination of brackish water can provide an important source of potable water in many parts of the world. Reverse osmosis (RO) and nanofiltration (NF) have become the technology of choice for many of these applications... more
ABSTRACT Inland desalination of brackish water can provide an important source of potable water in many parts of the world. Reverse osmosis (RO) and nanofiltration (NF) have become the technology of choice for many of these applications [T. Pankratz, The 19th IDA Worldwide Desalting Plant Inventory, Global Water Intelligence, Houston, TX, 2006]. However, large-scale deployment of RO/NF in inland locations would necessitate operation at relatively high product water recovery in order to maximize water resource utilization and minimize treatment costs and environmental challenges associated with disposal of the concentrate. Concentrate disposal is generally limited to one or two options for any given area and is directly related to land cost, energy costs, regulations, and the type and quantity of salts in the concentrate stream [M. Mickley, Concentrate management, in: M. Wilf (Ed.), The Guidebook to Membrane Desalination Technology: Reverese Osmosis, Nanofiltration and Hybrid Systems Process, Design, Applications and Economics, Balaban Desalination Publications, L'Aquila, Italy, 2007, p. 524; B. van der Bruggen, L. Lejon, C. Vandecasteele, Reuse, treatment, and discharge of the concentrate of pressure-driven membrane processes, Environ. Sci. Technol. 37 (2003) 3733–3738.]. Inland concentrate disposal options include reuse of concentrates, surface water discharge, sewer disposal, deep well injection, land applications, and evaporation ponds (followed by land filling of solids) [M. Mickley, Concentrate management, in: M. Wilf (Ed.), The Guidebook to Membrane Desalination Technology: Reverese Osmosis, Nanofiltration and Hybrid Systems Process, Design, Applications and Economics, Balaban Desalination Publications, L'Aquila, Italy, 2007, p. 524.]. This chapter provides an overview of post-RO/NF concentrate minimization technologies with the goal of minimizing the concentrate volume such that ultimate disposal options are more feasible. Examples of several of these technologies are also provided.
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Research Interests: Environmental Science, Chemistry, Environmental Chemistry, Water Pollution, Multidisciplinary, and 13 moreEnvironmental science and technology, Chemical Analysis, Dissolved organic matter, Sediment, Polychlorinated Biphenyl, Estuary, Total Organic Carbon, Dissolved Organic Carbon, Functional Group, Aeration, Organic Matter, Pore Water, and Distribution coefficient
Capacitive deionization (CDI) with carbon aerogels has been shown to remove various inorganic species from aqueous solutions, though no studies have shown the electrosorption behavior of multisolute systems in which ions compete for... more
Capacitive deionization (CDI) with carbon aerogels has been shown to remove various inorganic species from aqueous solutions, though no studies have shown the electrosorption behavior of multisolute systems in which ions compete for limited surface area. Several experiments were conducted to determine the ion removal capacity and selectivity of carbon aerogel electrodes, using both laboratory and natural waters. Although carbon aerogel electrodes have been treated as electrical double-layer capacitors, this study showed that ion sorption followed a Langmuir isotherm, indicating monolayer adsorption. The sorption capacity of carbon aerogel electrodes was approximately 1.0-2.0 x 10(-4) equiv/g aerogel, with ion selectivity being based on ionic hydrated radius. Monovalent ions (e.g., sodium) with smaller hydrated radii were preferentially removed from solution over multivalent ions (e.g., calcium) on a percent or molar basis. Because of the relatively small average pore size (4-9 nm) of the carbon aerogel material, only 14-42 m2/g aerogel surface area was available for ion sorption. Natural organic matter may foul the aerogel surface and limit CDI effectiveness in treating natural waters.
Research Interests: Environmental Science, Chemistry, Inorganic Chemistry, Electrochemistry, Carbon, and 14 moreMedicine, Multidisciplinary, Environmental science and technology, Adsorption, Aerogel, Sorption, Gels, Sodium, Capacitive Deionization, Electrodes, Carbon Fibers, Aqueous Solution, Ions, and Organic Chemicals
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... Each of three pretreatment scenarios produced effluent waters generally considered appropriate for use with RO [median turbidity of less than 0.1 Nephelometric turbidity unit (NTU) and mediansilt density index of less than 3]. Both... more
... Each of three pretreatment scenarios produced effluent waters generally considered appropriate for use with RO [median turbidity of less than 0.1 Nephelometric turbidity unit (NTU) and mediansilt density index of less than 3]. Both microfiltered and ozonated/ biofiltered waters ...
Research Interests:
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The Metropolitan Water District of Southern California (Metropolitan), in conjunction with Koch Membrane Systems (KMS), evaluated three generations of a 16″-diameter by 60″-long reverse osmosis (RO) element in parallel with a commercially... more
The Metropolitan Water District of Southern California (Metropolitan), in conjunction with Koch Membrane Systems (KMS), evaluated three generations of a 16″-diameter by 60″-long reverse osmosis (RO) element in parallel with a commercially available 8″-diameter element. Design inefficiencies in the first-generation 16″ element resulted in a 20% lower specific flux when compared to an 8″ element. After making improvements in element