Abstract: A method and apparatus for treating wastewater streams by adding, either separately or as a mixture, a nitrate containing compound and an alkaline material in an amount sufficient to achieve a lower concentration of atmospheric hydrogen sulfide and dissolved sulfides downstream of the addition as compared to the atmospheric hydrogen sulfide and dissolved sulfides present in the wastewater stream prior to the addition. By adding alkaline material in addition to a nitrate containing compounds, the amount of nitrate containing compound added can be reduced by at least 10% as compared to the amount of nitrate that would theoretically need to be added in the absence of alkaline material to achieve a comparable lower concentration of atmospheric hydrogen sulfide and dissolved sulfides in the wastewater stream.

Abstract: The present invention is drawn to a solid calcium hypochlorite particle having an available chlorine content of at least about 30% by weight and a water content of from about 2% to about 20% by weight; wherein said solid calcium hypochlorite particle is coated with about 0.01 to about 10% by weight of a deposit control agent comprising a sodium, potassium, lithium, calcium or magnesium salt of at least one of polyepoxysuccinic acid and polymaleic acid.

Abstract: A wastewater treatment facility incorporates a trivalent cation salt to promote coagulation of flocculent material. The trivalent cation salt is typically added between a primary and a secondary treatment stage in the wastewater treatment facility. The trivalent cation is typically an aluminum salt. The amount of trivalent cation can be optimized by targeting a (M/D)/T ratio of less than about 1.0, where M is a monovalent cation equivalent concentration and D is a divalent cation equivalent concentration in the wastewater and T is a mass of the trivalent cation in the sludge. The amount of trivalent cation can also be optimized by targeting a M/T ratio of less than about 1.0, where M is a monovalent cation equivalent concentration in the wastewater and T is a mass of the trivalent cation in the sludge.

Abstract: A filter screen that is used in filtering water and that includes a frame and a grid assembly that is supported by the frame for movement. The grid assembly includes a continuous unbroken drive chain having a guide link, and a screen panel. The screen panel is coupled to the guide link for selective movement between an operating condition and a maintenance condition. When the screen panel is in the operating condition the screen panel is fixed relative to the guide link for movement with the guide link and for filtering water. In the maintenance condition, the screen panel is pivotable relative to the guide link to permit access to the interior of the filter screen for inspection of chain components.

Abstract: An apparatus and method for distributing a fluid. A fluid distribution device includes a flow chamber comprising an inlet and an outlet, an equalization chamber; and a diaphragm separating the flow chamber and the equalization chamber, wherein a valve positioned in a flow path between the flow chamber inlet and the flow chamber outlet comprises a valve body coupled to the diaphragm.

Abstract: A hydrocyclone bundle comprising a plurality of hydrocyclone liners and a plate assembly for use in liquid-liquid separation is disclosed. The hydrocyclone bundle may be used in new or existing separators. The hydrocyclone liners may be oppositely positioned within the hydrocyclone bundle. The plate assembly may collect and distribute overflow and underflow effluents from the hydrocyclone liners.

Abstract: A system and method for treating water in an aqueous system includes measuring or characterizing one or more specific oxidizing species by utilizing species-specific or selective techniques. The selective techniques utilize an amperometric or potentiometric sensor having a selective membrane or analytical techniques to provide an indication of a concentration of one or more oxidizing species. The system and method also determines an overall characteristic of the water, which can be used to control addition of additional oxidizing species.

Abstract: An activated carbon/metal oxide filter element is disclosed. The filter element may be prepared by blending an activated carbon, a metal oxide, and a binder to form a filter media mixture, shaping the filter media mixture into a filter body. The filter body may be calcined to form a filter element. The activated carbon/metal oxide filter element may be used to remove odorous compounds, acidic gases, and volatile organic compounds from a gas.

Abstract: The clarifier of the present invention includes a tank, an influent pier, and a FEDWA. The tank that includes a bottom and a wall. The influent pier projects upwardly from the bottom of the tank along an axis. The influent pier includes ports that direct flow of the solution outwardly from the influent pier. The FEDWA separates the flow of the solution that is discharged by the ports and that flows into the tank. The separated flow of the solution includes a first flow portion that is directed in a first direction that is generally tangential with respect to the axis of the influent pier, a second flow portion that is directed in a second direction that is opposite to the first direction of the first flow portion, and a third flow portion that is directed in a third direction toward the axis.

Abstract: An electrodeionization apparatus and method for purifying a fluid. A fluid, such as water, can be purified by removing weakly ionizable species from the fluid. Weakly ionizable species may be dissociated at different pH levels to facilitate removal from the fluid in an electrodeionization device.

Abstract: The instant invention is a device and method for its use which includes the addition of a deviation compensation function effective to automatically adjust the offset used in time-based proportional control. Inclusion of this improvement finds particular utility in situations like public pools where daily bather load varies depending on weather and other unpredictable factors.

Abstract: A filter screen that is used in filtering water and that includes a frame and a grid assembly that is supported by the frame for movement. The grid assembly includes a continuous unbroken drive chain having a guide link, and a screen panel. The screen panel is coupled to the guide link for selective movement between an operating condition and a maintenance condition. When the screen panel is in the operating condition the screen panel is fixed relative to the guide link for movement with the guide link and for filtering water. In the maintenance condition, the screen panel is pivotable relative to the guide link to permit access to the interior of the filter screen for inspection of chain components.

Abstract: Heat transfer in non-turbulent highly viscous mixed-phase flowing streams can be improved by altering flow characteristics using spiral-shaped elements to eliminate boundary phenomena. The spiral-shaped element promotes helical or spiral flow paths to reduce or eliminate temperature gradients associated with laminar flow characteristics.

Abstract: This invention relates to ion exchange resins that have a reduced amount of physically adsorbed organic compounds, as well as methods of producing and using such resins. In particular, the amount of extractable total organic carbon on the resins may be less than about 200 parts per trillion by wet weight, as measured using gas chromatography/mass spectrometry. This invention also relates to methods of treating water that use such resins.

Abstract: The invention recites a filter comprising a block including an outer wall defining an inner chamber and a block exterior, and a conduit having a conduit wall, a first conduit end, a second conduit end, and an inner flow path providing fluid communication between the first and second conduit ends. The conduit wall includes an orifice therethrough. The conduit is coupled to the block such that the first conduit end is in fluid communication with the inner chamber of the block and the second conduit end and the orifice are in fluid communication with the block exterior.

Abstract: The invention recites a filtration system including a block including a first wall and a second wall substantially parallel to the first wall. A top surface that is substantially perpendicular to the first wall is disposed between, and coupled to, the first and second walls to at least partially define an inner chamber. The top surface further includes an orifice defining a passageway between a block exterior and the inner chamber. A plate including a plurality of slots, each slot having a width of less than about 0.065 inches, and a slot outlet, is coupled to the top surface of the block. The slot outlets in the plate are substantially coplanar and the plate, when coupled to the block, substantially covers the orifice.

Abstract: The invention recites a filter including a plurality of filter cells, each filter cell including a bottom surface and at least one side surface and defining a maximum influent level. The filter also includes a distribution box including a base and at least one wall, the base and wall at least partially defining a distribution region therein. The distribution box is supported such that the base is at or below the filter cell maximum influent level. The filter further comprises a plurality of drop pipes, each pipe having a first end and a second end, the first end of each pipe is in fluid communication with the distribution region, and extends above the base of the distribution box. The second end of the pipe is in fluid communication with one of the plurality of filter beds.

Abstract: A grit washer is disclosed having a bearing assembly which supports a conveyor and which is removably mounted to the exterior of the grit washer tank. With the bearing assembly being mounted to the exterior of the tank, the bearing assembly is easily accessible without the need to drain the tank or lift the screw conveyor out of the tank. The bearing assembly can therefore be easily inspected, repaired and/or replaced as necessary. The external placement of the bearing assembly also isolates the bearing assembly from the abrasive grit in the tank thereby minimizing the damage to the bearing assembly caused by the grit.

Abstract: Active bromine-containing solutions are produced and stabilized by reacting bromate and bromide salt solutions with an amino-complexing agent, such as sulfamic acid or sulfamate salt. The reaction is performed at a pH of less than 1 to create a complexed hypobromate. The pH of the active bromine-containing solution is raised to between 4 and 10 by adding an alkali to improve stability. Moreover, the solution is maintained below 30° C. during the alkali addition to retain bromine equivalent activity.

Abstract: An electrodeionization apparatus and method for purifying a fluid. A fluid, such as water, can be purified by removing weakly ionizable species from the fluid. Weakly ionizable species may be dissociated at different pH levels to facilitate removal from the fluid in an electrodeionization device.