Abstract: Aspects described herein provide a computer implemented radio frequency propagation simulation tool to allow the simulation of radio frequency propagation across a topographic area which has been very finely mapped in three dimensions to include possible obstructions to high frequency radio waves. A computer implemented RF propagation simulation tool may identify any possible obstructions one edge of which may lie in a simulated RF propagation path between two points, and apply an edge based RF diffraction model (a so-called “knife edge diffraction” model) thereto to simulate the RF propagation around the obstruction. In some aspects, a computer implemented RF propagation simulation tool may identify possible obstructions which in their entirety lie within the width of a simulated RF propagation path, and apply a further diffraction model (a so-called “shield diffraction” model) thereto to simulate the RF propagation around the obstruction.

Abstract: Aspects described herein provide a computer implemented radio frequency propagation simulation tool to allow the simulation of radio frequency propagation across a topographic area which has been very finely mapped in three dimensions to include possible obstructions to high frequency radio waves. A computer implemented RF propagation simulation tool may identify any possible obstructions one edge of which may lie in a simulated RF propagation path between two points, and apply an edge based RF diffraction model (a so-called “knife edge diffraction” model) thereto to simulate the RF propagation around the obstruction. In some aspects, a computer implemented RF propagation simulation tool may identify possible obstructions which in their entirety lie within the width of a simulated RF propagation path, and apply a further diffraction model (a so-called “shield diffraction” model) thereto to simulate the RF propagation around the obstruction.

Abstract: Aspects and embodiments of the present disclosure are directed to apparatus and methods for the photooxidation of sulfur-containing contaminants in air. In one example, an odor control system comprises a source of air contaminated with a sulfur-containing compound and a UV oxidation reactor having an inlet in fluid communication with the source of contaminated air. The reactor includes a source of UV radiation disposed within the reactor and a reflective coating disposed on internal surfaces of the reactor.

Abstract: Aspects and embodiments of the present disclosure are directed to apparatus and methods for the photooxidation of sulfur-containing contaminants in air. In one example, an odor control system comprises a source of air contaminated with a sulfur-containing compound and a UV oxidation reactor having an inlet in fluid communication with the source of contaminated air. The reactor includes a source of UV radiation disposed within the reactor and a reflective coating disposed on internal surfaces of the reactor.

Abstract: An integrated process for removing sulfate from water sources, such as pretreated acid mine drainage (AMD). The multivalent cation (MVC) content of a sulfate stream is reduced by strong acid cation (SAC) ion exchange and sulfate is concentrated with a membrane system and separated as precipitate and overflow. Precipitation results from reaction of sulfate with MVC produced by regeneration of SAC with sodium chloride. The overflow is reacted with carbonate to precipitate MVC, generate sodium chloride and give a further overflow stream. This latter stream is concentrated to a level capable of being a regenerant for the SAC and when needed, used to regenerate the SAC and produce MVC for sulfate precipitation. The process minimizes the use of chemicals by treating, reconcentrating and recycling input species. Capital expenditures are minimized by precipitation of only side streams.

Abstract: Aspects and embodiments of the present invention are directed to apparatus and methods of filtering a fluid to reduce a level of at least one contaminant therein. The filtering of the fluid may be accomplished with a radial flow filtration column comprising a fluid chamber having an inlet, an outlet, and a side wall, an inner permeable retainer positioned in the fluid chamber, an outer permeable retainer positioned in the fluid chamber spaced apart from and surrounding the inner permeable retainer, a media bed compartment formed between the inner permeable retainer and the outer permeable retainer, and an adjustable element biased into the media bed compartment and configured to maintain a predetermined packing density of a media bed to be disposed within the media bed compartment.

Abstract: Ultraviolet reactors having an ultraviolet light source for treating a fluid are disclosed. In one embodiment, a reactor is disclosed which includes a vessel having an inlet for receiving fluid and an outlet for discharging fluid. The vessel further includes a plurality of segmented baffles. The baffles further include a partial circumferential edge section that terminates in a vertical edge section to form right and left segmented baffles. The left and right segmented baffles are arranged in an alternating pattern in the vessel to provide plug flow and enhanced radial mixing.

Abstract: Aspects and embodiments of the present invention are directed to apparatus and methods of filtering a fluid to reduce a level of at least one contaminant therein. The filtering of the fluid may be accomplished with a radial flow filtration column comprising a fluid chamber having an inlet, an outlet, and a side wall, an inner permeable retainer positioned in the fluid chamber, an outer permeable retainer positioned in the fluid chamber spaced apart from and surrounding the inner permeable retainer, a media bed compartment formed between the inner permeable retainer and the outer permeable retainer, and an adjustable element biased into the media bed compartment and configured to maintain a predetermined packing density of a media bed to be disposed within the media bed compartment.

Abstract: A high recovery sulfate removal process comprises treating a feed water stream conditioned with antiscalant from a source with a reverse osmosis membrane system to produce a purified water permeate stream and a reject stream containing the retained or rejected ions and organic matter. The reject stream is further treated to remove dissolved and suspended species. The reject stream flows to a desaturation/clarification process. A preferred process includes a constant stirred tank reactor (CSTR) where co-precipitation agent is added followed by a clarifier. Water recycled from the clarifier overflow is blended with feed water stream. The removed solids are collected as sludge or a slurry and disposed of in a manner consistent with applicable regulations.

Abstract: An integrated process for removing sulfate from water sources, such as pretreated acid mine drainage (AMD). The multivalent cation (MVC) content of a sulfate stream is reduced by strong acid cation (SAC) ion exchange and sulfate is concentrated with a membrane system and separated as precipitate and overflow. Precipitation results from reaction of sulfate with MVC produced by regeneration of SAC with sodium chloride. The overflow is reacted with carbonate to precipitate MVC, generate sodium chloride and give a further overflow stream. This latter stream is concentrated to a level capable of being a regenerant for the SAC and when needed, used to regenerate the SAC and produce MVC for sulfate precipitation. The process minimizes the use of chemicals by treating, reconcentrating and recycling input species. Capital expenditures are minimized by precipitation of only side streams.

Abstract: Wastewater streams from semiconductor processing operations are treated to reduce the concentration therein of one or more metal species to a satisfactory level. The disclosed systems and technique utilize complexing ion exchange media to treat the wastewater streams having a significant concentration of oxidizing species and high solids concentration.

Abstract: Wastewater streams from semiconductor processing operations are treated to reduce the concentration therein of one or more metal species to a satisfactory level. The disclosed systems and technique utilize complexing ion exchange media to treat the wastewater streams having a significant concentration of oxidizing species.

Abstract: Wastewater streams from semiconductor processing operations are treated to reduce the concentration therein of one or more metal species to a satisfactory level. The disclosed systems and technique utilize complexing ion exchange media to treat the wastewater streams having a significant concentration of oxidizing species.

Abstract: Contaminants in ground water, waste water and industrial effluents are removed using a contaminant removing media packed in a radial flow column. The radial flow column includes a fluid chamber having cylindrical inner and outer screens positioned therein. A contaminant removing media is packed in a media bed between the inner and outer screens. Contaminated water is passed through the column with the water passing through the outer screen, the contaminant removing media and out the inner screen. The contaminant removing media preferably has a size in a range between 50-400 mesh and more preferably between 150-400 mesh.