Abstract: Methods and apparatus for treating wastewater are described, one method embodiment including the steps of flowing a mixed liquor suspended solids to a high rate clarification stage, forming a clarifier effluent, a first waste activated sludge stream, and a return waste activated sludge stream. The high rate clarifier effluent stream then flows to a membrane stage that includes a membrane media, producing a membrane reject (retentate) stream and a treated effluent (permeate) stream. Optionally, the methods include routing a screened raw wastewater to an anaerobic and/or aerated anoxic stage and introducing a gas comprising oxygen to the wastewater during the aerated anoxic stage, and optionally allowing the product of this stage to flow to an aeration stage prior to the high rate clarification stage.

Abstract: Semi-submersible floating decanters and methods of use are provided. The decanters are moveable between a non-decant position and a decant position, and include a float forming an internal cavity, the float having a central annulus, a weir having an inlet opening and positioned within the center of the annulus and fixedly connected to the float forming a passage between the float and the weir, and a discharge conduit connected to the weir for discharging a supernatant fluid therefrom. A depth adjusting mechanism is provided for moving the decanter within a liquid between a non-decant position wherein the inlet opening is above the surface of the liquid and a decant position wherein the inlet opening is positioned within the supernatant to allow the supernatant to be withdrawn, the depth adjusting mechanism including a pumping mechanism for moving a fluid relative to the internal cavity.

Abstract: Decanter mooring systems and methods are provided. Decanter mooring systems of the invention include a decanter having a discharge orifice, the decanter disposed within a reactor containing a liquid and adapted to move vertically in relation to the surface of the liquid, a discharge conduit connected to the discharge orifice so as to be moveable in relationship with the decanter, and a stabilizing arm having a first end moveably connected to the reactor in a manner to limit the lateral movement of the decanter in the reactor.

Abstract: Systems and processes are presented which reduce space requirements for pasteurization equipment. The systems include an enclosure defining a heating chamber, and a liquid flow conduit positioned within the heating chamber, the conduit having an inlet and an outlet and defining a flow path for a slurry to be pasteurized. The slurry is heated via indirect contact heat transfer from ambient temperature to a minimum temperature after the slurry is introduced into the flow conduit. The means for heating is positioned inside the heating chamber.

Abstract: A liquid filtering apparatus is placed in a vessel having a bed of filtration material and an intake for introducing unfiltered liquid, that includes a washbox, an airlifting tube extending from the washbox and including an intake end and means for introducing a primary gas to the airlifting tube, the airlifting tube passing through a central pipe, which extends from just below the washbox to a position just above the intake end. At least one screen cartridge is oriented in a generally angular downward direction in the bed and is in communication with an effluent chamber defined in part by the outer surface of the central pipe. A reject line extends from the washbox, and an effluent collector extends from the effluent chamber. A method of filtering and cleaning the filtration material is also disclosed.

Abstract: A belt roller for belt filter presses having a roller body and two end pieces. Each end piece has a thickened portion positioned adjacent a center of the end piece. The thickened portion can resemble a variety of shapes when viewed in cross-section.

Abstract: A liquid filtering apparatus is placed in a vessel having a bed of filtration material and an intake for introducing unfiltered liquid, that includes a washbox, an airlifting tube extending from the washbox and including an intake end and means for introducing a primary gas to the airlifting tube, the airlifting tube passing through a central pipe, which extends from just below the washbox to a position just above the intake end. At least one screen cartridge is oriented in a generally angular downward direction in the bed and is in communication with an effluent chamber defined in part by the outer surface of the central pipe. A reject line extends from the washbox, and an effluent collector extends from the effluent chamber. A method of filtering and cleaning the filtration material is also disclosed.

Abstract: A liquid filtering apparatus is placed in a vessel having a bed of filtration material and an intake for introducing unfiltered liquid, that includes a washbox, an airlifting tube extending from the washbox and including an intake end and means for introducing a primary gas to the airlifting tube, the airlifting tube passing through a central pipe, which extends from just below the washbox to a position just above the intake end. At least one screen cartridge is oriented in a generally angular downward direction in the bed and is in communication with an effluent chamber defined in part by the outer surface of the central pipe. A reject line extends from the washbox, and an effluent collector extends from the effluent chamber. A method of filtering and cleaning the filtration material is also disclosed.

Abstract: An improved vertical filtration unit which includes an airlift and a washbox designed for more efficient washing of dirt particles from the filtration material. The washbox consists of a filter media shield, and a washbox skirt for washing of the filtration material. A throttling valve on the wash water discharge line regulates the overall cleaning rate of the unit. The filtered liquid is discharged via a riser pipe which feeds into a filtered liquid box before exiting the filtration unit.

Abstract: A belt press having a frame with a first belt and a second belt rotatably mounted on the frame. A curved inlet guide is movably carried on the frame. The inlet guide has a decreasing radius of curvature from an inlet end to an exit end. A positioning assembly is mounted on the frame and is attached to the inlet end of the inlet guide to raise and lower the inlet end of the inlet guide.

Abstract: An improved vertical filtration unit which includes an airlift and a washbox designed for more efficient washing of dirt particles from the filtration material. The washbox consists of a filter media shield, and a washbox skirt for washing of the filtration material. A throttling valve on the wash water discharge line regulates the overall cleaning rate of the unit. The filtered liquid is discharged via a riser pipe which feeds into a filtered liquid box before exiting the filtration unit.

Abstract: Method of filtering liquid using a vertical filter, which includes media, an airlift, a washbox, a reject box, a filtrate chamber, and an effluent box. The method of filtration and media cleaning is automatic. The filtered liquid is collected by multi-cartridge screens before entering a filtrate chamber. The filtrate flows from the filtrate chamber into an effluent weir box. The liquid level in the filter is controlled by an effluent weir in the effluent weir box. The reject line is below the water level in the filter, which provides the driving force for the reject flow. The reject rate is controlled by liquid level in the filter tank and a throttling valve on the reject discharge line. The washbox includes a filtration material shield, a filtration material/dirtied liquid separation zone, and a washbox skirt with a washbox isolator, which prevents the dirt in the washbox form entering the influent zone.

Abstract: A belt press having a frame with a first belt and a second belt rotatably mounted on the frame. A curved inlet guide is movably carried on the frame. The inlet guide has a decreasing radius of curvature from an inlet end to an exit end. A positioning assembly is mounted on the frame and is attached to the inlet end of the inlet guide to raise and lower the inlet end of the inlet guide.

Abstract: A scraper blade assembly utilizes an over-center spring to bias the scraper blade assembly both into engagement and out of engagement with a conveyor, such as a moving belt, on a device for separating solids from liquids. The over-center spring extends between a fixed attachment point on the device and a pivoting attachment point on a handle secured to the scraper blade assembly. The invention is particularly applicable to belt filter presses and gravity belt sludge thickeners. An over-center spring may be secured to both ends of the scraper blade assembly to minimize torsional deformation of the scraper blade by the material being separated from the moving belt.