Abstract: Chlorine dioxide generation systems and methods are disclosed. One or more reactants, such as sodium hypochlorite, may be electrolytically generated on-site for delivery to a reaction column. Low concentration reactants may be used to generate chlorine dioxide as part of a mixed oxy-chloro product stream containing free available chlorine. In at least one embodiment, an optical analyzer may be positioned along a reactant feed line to measure a concentration of reactant supplied to a reaction column. A controller may adjust a flow rate of the reactant in response to information provided by the optical analyzer. The controller may also perform pH control within the system. In some embodiments, the chlorine dioxide generator may be incorporated in an all-liquid water disinfection system.

Abstract: A filtration arrangement including one or more membrane modules (5) positioned vertically within a feed tank (6), each membrane module (5) having one or more membranes positioned therein. An aeration hood (10) having an upper wall (11) and one or more downwardly extending side walls (12, 13) is configured to at least partially shroud the membrane modules (5) within the tank (6). The aeration hood (10) includes a number of open-ended tubes (14), each extending downwardly from the upper wall (11) and forming a respective opening (15) therein. Each tube (14) is adapted to have at least one of the modules (5) mounted therein and extending through the respective openings (15) in the upper wall (11) so as to at least partially surround an outer periphery of an associated module or modules (5). One or more aeration openings (17) are provided in each tube (14) at a location spaced from a proximal end of the tube (16).

Abstract: A method of cleaning a membrane surface immersed in a liquid medium with a fluid flow, including the steps of providing a randomly generated intermittent or pulsed fluid flow along the membrane surface to dislodge fouling materials therefrom. A membrane module is also disclosed comprising a plurality of porous membranes (6) or set of membrane modules (5) and a device (11) for providing a generally randomly generated, pulsed fluid flow such that, in use, said fluid flow moves past the surfaces of said membranes (6) to dislodge fouling materials therefrom.

Abstract: A method and system of treating wastewater that can provide operating flexibility is disclosed. The system is operated with a sequencing batch reactor, which is typically cycling to any of fill, react, settle, decant, and idle stages, to treat the wastewater. The system can further utilize a membrane filtration system to further treat water from the sequencing batch reactor and produce suitable water. A solids-reducing system can be connected to the sequencing batch reactor and reduce an amount of biodegraded solids by converting the character or distribution of microorganisms population in the biomass.

Abstract: An apparatus for potting membranes. The apparatus may include a mould for receiving ends of the membranes, means for forming a first layer of a curable resin material around the ends in the mould, and means for applying a second layer of a flexible resin material to the first layer prior to full curing of the first layer. The flexible resin material may be chemically reactive with the curable resin material to form an adhesive bond therebetween. A potting sleeve may be positioned within the mould. A centrifuge may receive the curable resin and/or the flexible resin material upstream of the mould.

Abstract: A hybrid method and system of treating wastewater with reduced energy usage is disclosed. The treatment system has a sorption system, an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system, and an aerobic treatment tank that partially reduces oxygen demand of a portion of the sludge from the sorption tank.

Abstract: A system and method for the treating at least one undesirable constituent in an aqueous mixture utilizing a particulate solids catalyst. The aqueous mixture and the particulate solids catalyst form a slurry which is wet oxidized.

Abstract: A method and system of controlling addition of a treating agent based on a control function comprising a plurality of demand values is disclosed. Process parameters of a fluid to be treated are measured and one or more control signals are generated based on the measured process values and the control function. The control signals are used to actuate a treating agent dosing system and also used to monitor and compare the levels, status or condition of the treating agent. Additional features of the invention compensate for rain events.

Abstract: Hydrophilic porous polymeric membranes with high permeabilities, and processes for the preparation thereof are disclosed. Membranes may be prepared by including a preferably hydrophilic cross-linkable component such as PVP (either by inclusion into the polymer dope prior to casting, or coating or quenching cast membranes); and treating the polymeric microfiltration or ultrafiltration membrane with a crosslinking agent to cross-link said cross-linkable component. Preferred cross-linking agents include Fenton's reagent.

Abstract: A membrane module (3) comprising a plurality of porous hollow membranes (8). The membranes (8) extend between and are fixed at each end in a header (5, 6). One header (6) has one or more of openings (12) formed therein. The openings (12) are in fluid communication with a source of gas and/or liquid (13, 14, 15). The other of the headers (5) is sealingly connected to and in fluid communication with a head-piece (9). The head-piece (9) is adapted to couple to an associated head-piece of a further module to form a rack of modules (17). A potting head (6) for use in mounting porous hollow membranes (8) is also disclosed comprising a preformed potting element (29). The potting element (29) includes one or more cavities (30) for receiving curate potting material which, in use, supports said membranes (8).

Abstract: In a tank for treating wastewater and including a first plurality of air diffuser elements and a second plurality of air diffuser elements, means for adjusting the relative height of the first diffuser elements with respect to the height of the second diffuser elements in response to changing operating conditions in the tank and changes in the characteristics of the diffusers.

Abstract: A process for treating waste water to remove phosphorous and nitrogen in a treatment system including an anaerobic zone (5) containing an anaerobic mixed liquor having organisms which release phosphorous into the anaerobic mixed liquor; an anoxic zone (7) containing an anoxic mixed liquor having organisms which uptake phosphorous and denitrify the anoxic mixed liquor and an aerobic zone (9) containing an aerobic mixed liquor having organisms which uptake phosphorous and nitrify the aerobic mixed liquor; the process including the steps of providing wastewater to be treated into the anaerobic zone (5) and communicating anaerobic mixed liquor from the anaerobic zone (5) to the anoxic zone (7). The anoxic mixed liquor is then communicated from the anoxic zone (7) to the anaerobic zone (5) and the anoxic mixed liquor from the anoxic zone (7) to the amble zone (9).

Abstract: A water treatment system provides treated or softened water to a point of use by removing a portion of any hardness-causing species contained in water from a point of entry coming from a water source, such as municipal water, well water, brackish water and water containing foulants. The water treatment system typically treats the water containing at least some undesirable species before delivering the treated water to a point of use. The water treatment system has a reservoir system in line with an electrochemical device. The electrochemical device of the water treatment system is operated at a low current and low flow rate to minimize water splitting or polarization, which minimizes scale formation.

Abstract: Aspects and embodiments of the present application are direction to systems and methods for treating fluids and to systems and methods for cleaning membrane modules used in the treatment of fluids. Disclosed herein is a membrane filtration system and a method of operating same. The membrane filtration system comprises a plurality of membrane modules positioned in a feed tank, at least one of the membrane modules having a gas slug generator positioned below a lower header thereof, the gas slug generator configured and arranged to deliver a gas slug along surfaces of membranes within the at least one of the membrane modules and a global aeration system configured to operate independently from an aeration system providing a gas to the gas slug generator, the global aeration system configured and arranged to induce a global circulatory flow of fluid throughout the feed tank.

Abstract: Systems and methods for metering fluid flow are disclosed. A valve may generally include an orifice plate, and a disc positioned adjacent to the orifice plate. An orientation of the disc relative to the orifice plate is adjustable to regulate a fluid flow rate through the valve. An effective area of an aperture in the orifice plate may be manipulated to adjust the fluid flow rate. In some configurations, the valve may provide sonic flow control or differential pressure regulation. In some applications, a controller may adjust the orientation of the disc relative to the orifice plate to maintain a substantially constant pressure drop across the orifice plate in order to determine a fluid flow rate through the valve.

Abstract: Porous polymeric membranes formed from a hydrophobic polymer, such as halar having membrane pores of a size sufficient to permit gas and/or vapor permeation 0.05 ?m to 5 ?m without permitting the flow of a hydrophilic fluid across the membrane. Pore distribution is uniform and porosity is high, in some cases up to 80%. Membranes may be in the form of a flay sheet or hollow fibre for example and can be used in a variety of applications such as stripping HF gas, degassing of caustic solution, chlorine gas/alkaline filtration, degassing tap water to remove dissolved chlorine. Processes used to make such membranes can be carried out using relatively non toxic solvents such as citric acid ethyl ester or glycerol triacetate.

Abstract: The disclosed techniques involve electrical separation systems that allow recovery of species from feedstreams, typically aqueous solutions. The disclosed techniques can also provide electrical separation systems having reduced tendency to form scale especially when water is being purified to reduce the concentration of hardness-causing species.

Abstract: Systems and methods for wastewater treatment. A nitrate source may be dosed to a collection tank, such as a wet well, for downstream control of hydrogen sulfide levels in the wastewater. A source of a strong oxidizer may also be dosed to the wet well. The oxidizer, such as chlorite, may temporarily interrupt denitrification processes in the wet well to prevent floatation of undesirable constituents therein. The oxidizer dosage may be generally consistent with the nitrate dosage. An ORP sensor may facilitate regulation of dosing. The nitrate and the oxidizer may be present in a single mixture to be dosed to the wet well.

Abstract: Systems and methods for wastewater treatment. A nitrate source may be dosed to a collection tank, such as a wet well, for downstream control of hydrogen sulfide levels in the wastewater. A source of a strong oxidizer may also be dosed to the wet well. The oxidizer, such as chlorite, may temporarily interrupt denitrification processes in the wet well to prevent floatation of undesirable constituents therein. The oxidizer dosage may be generally consistent with the nitrate dosage. An ORP sensor may facilitate regulation of dosing. The nitrate and the oxidizer may be present in a single mixture to be dosed to the wet well.