Abstract: In a sewage treatment plant with a membrane bioreactor (MBR), raw untreated or partially treated wastewater (influent) and/or mixed liquor in the intensified process is superoxygenated. In a preferred form of the process the influent is superoxygenated such that membrane air scouring requirements are reduced. Influent may be fed to a swing zone where denitrification and nitrification occur simultaneously through process control. In one embodiment superoxygenation is conducted in an internal recycle stream of the mixed liquor, with oxygen content supersaturated preferably to over 300 parts per million. Due to the active evolution of oxygen gas from the supersaturated stream, occurring preferably by seeding the supersaturated stream with air bubbles, the supersaturated oxygen can serve the dual purposes of meeting process oxygen demands and providing part of air scouring requirements for the membranes.

Abstract: In a wastewater treatment plant a clarifier is fitted with piping and a pump to withdraw settled sludge from the bottom of the tank upwardly through the tank's center column and radially out from the clarifier via an exit pipe above the liquid level. The exit pipe can be supported on a fixed walkway. At the bottom end of the central tower is a manifold device for collecting settled sludge, including an annular preferably cylindrical wall, a central pipe hub and at least one pipe branch extending from an opening in the cylindrical wall radially inwardly to the central hub. Sludge is drawn up through a vertical sludge return pipe by a pump located preferably above the tank's liquid level, drawing sludge into pipe branches of the manifold device and through the hub to the sludge return pipe, then out through the exit pipe.

Abstract: An orbital wastewater treatment system generally including a tank assembly and at least one impeller in the tank assembly for moving mixed liquor under process about the tank assembly is provided with an wastewater inflow sensor, an impeller power meter, and a control unit for periodically and incrementally varying impeller speed and weir height in order to reduce energy consumption. Operating such a wastewater treatment system comprises flowing mixed liquor or wastewater into a treatment pool in the tank assembly, rotating the impeller within the pool to move the mixed liquor or wastewater, and adjusting, in concert, a rate of rotation of the impeller and a level or depth of the pool to reduce a rate of energy usage per unit inflow volume while maintaining at least one process parameter such as dissolved oxygen content substantially constant at a given level in the pool.

Abstract: A traveling band screen has a support frame assembly, two continuous chains movably mounted to the support frame assembly for motion along respective mutually parallel endless paths, a plurality of mesh members each secured on opposing edges to the chains, and a plurality of rollers rotatably mounted to each of the chains. One or more of the rollers are split rollers. Each such split roller has a respective rotation axis extending perpendicularly to the respective chain and accordingly to the path of motion of the chin. Each split roller has two roller halves secured to one another via elongate fasteners that extend parallel to the respective roller rotation axis.

Abstract: A hydrocyclone (1) for separating a liquid mixture into a heavy fraction including heavy particles and alight fraction, comprising a housing (2) forming an elongated separation chamber (3) having a circumferential wall (4), abase end (5),an apex end (6), at least one inlet member (7) for supplying a liquid mixture into the separation chamber (3), at least one of the inlet member/s(7) positioned at the base end (5), a first outlet member (8) for discharging separated light fraction from the separation chamber (3) at the base end (5), a second outlet member (9) for discharging separated heavy fraction from the separation chamber (3) at the apex end (6), means (10) for supplying the liquid mixture to the separation chamber (3) via the at least one inlet member (7), so that during operation a liquid stream is generated as a helical vortex (11) about a centre axis (12) in the separation chamber (3), said helical vortex (11) extending from the base end (5) to the apex end (6), a first flow deflection means arranged

Abstract: An orbital wastewater treatment system generally including a tank assembly and at least one impeller in the tank assembly for moving mixed liquor under process about the tank assembly is provided with an wastewater inflow sensor, an impeller power meter, and a control unit for periodically and incrementally varying impeller speed and weir height in order to reduce energy consumption. Operating such a wastewater treatment system comprises flowing mixed liquor or wastewater into a treatment pool in the tank assembly, rotating the impeller within the pool to move the mixed liquor or wastewater, and adjusting, in concert, a rate of rotation of the impeller and a level or depth of the pool to reduce a rate of energy usage per unit inflow volume while maintaining at least one process parameter such as dissolved oxygen content substantially constant at a given level in the pool.

Abstract: A multistage immersion type membrane separator includes a liquid air separator, the liquid air separator including an outlet tube, an inlet tube, and a skirt. The outlet tube is cylindrical and has a outlet tube diameter, and the inlet pipe has an inlet pipe diameter of less than the outlet tube diameter. The inlet pipe is attached to and in communication with the outlet tube so that a mixed flow of air and liquid passing through the inlet tube is introduced into the outlet tube and flows circumferentially around the inside of the outlet tube. The inlet pipe is attached to the cylindrical outlet tube so that the inlet pipe is perpendicular to the outlet tube. The outlet tube has two ends, one end being closed and the other end being open. The skirt is attached to the outlet tube and is concentric with the outlet tube. The skirt is attached to the closed end of the outlet tube, and extends to just past the point of attachment of the inlet tube to the outlet tube.

Abstract: An orbital wastewater treatment system includes a tank assembly, at least one impeller, a flow-diversion mechanism, an actuator, optionally at least one sensor disposed in the tank assembly, and a control unit. The tank assembly has an anoxic zone and an aerobic zone and passages between the two zones. The impeller is disposed in the tank assembly for aeration and for moving mixed liquor under process about the tank assembly. The flow-diversion mechanism is disposed at at least one of the passages between the aerobic and the anoxic zone. The actuator is operatively connected to the gate for regulating the flow state or configuration thereof in response to a signal generated by the control unit at least partially pursuant to a predetermined schedule and/or at least partially in accordance with input from the sensor.

Abstract: Flat-sheet membrane filter assemblies require open space around equipment to form a viable path for an internal recycle or roll pattern. Creating a dedicated roll pattern for individual filter assemblies is space intensive and imposes process constraints on tank dimensions. A hollow wall or series of pipes forms a recycle wall designed to consolidate roll patterns and reduces space requirements. The recycle wall is designed such that the structural components also serve as a mixed liquor distribution system for the necessary roll pattern. Fixed vertically oriented conduit and sectional channel pieces allow for easy access and removal of membrane filter assemblies installed side by side. Feeding mixed liquor, air and or influent to the bottom of filter assemblies via submerged conduit improves process efficiency when coupled with return channels spaced not more than 10 feet away and above assemblies.

Abstract: In a sewage treatment system, microconstituents, including personal care products and pharmaceutical materials, often difficult to degrade biologically, are removed by supersaturating the untreated wastewater feed with ozone. This breaks down refractory microconstituents into more readily biodegradable materials, subsequently treated preferably in an activated sludge membrane bioreactor process. The oxygen byproduct of ozonation is utilized by feeding the oxygen into an aerobic part of the plant to meet a portion of the biological demand, thereby increasing efficiency of ozone use in the process.

Abstract: The device is for the dilution of dewatered cellulose pulp that maintains a consistency of 20-30% or greater. By shredding of the pulp to a finely divided dry-granulate, dilution to a homogeneous consistency in the medium consistency range can take place exclusively through hydrodynamic effects from the addition of dilution fluid. The dilution fluid is added to granulate at a position at which granulate is in free fall in a standpipe and above a level Liqlev of diluted pulp in the standpipe. A number of nozzles are arranged around the periphery of the stand pipe, directed in towards the center of the stand pipe, obliquely downwards in the direction of fall of the granulate. It is possible through this simplified procedure to avoid completely the conventional dilution screws, and this reduces the investment costs and operating costs, while at the same time unnecessary mechanical influence of the pulp fibers can be avoided.

Abstract: In a sewage treatment plant with a membrane bioreactor (MBR), raw untreated or partially treated wastewater (influent) and/or mixed liquor in the intensified process is superoxygenated. In a preferred form of the process the influent is superoxygenated such that membrane air scouring requirements are reduced. Influent may be fed to a swing zone where denitrification and nitrification occur simultaneously through process control. In one embodiment superoxygenation is conducted in an internal recycle stream of the mixed liquor, with oxygen content supersaturated preferably to over 300 parts per million. Due to the active evolution of oxygen gas from the supersaturated stream, occurring preferably by seeding the supersaturated stream with air bubbles, the supersaturated oxygen can serve the dual purposes of meeting process oxygen demands and providing part of air scouring requirements for the membranes.