According to at least one aspect, the invention provides a filter assembly (100) comprising a tubular housing and a filter device (70) locateable to extend longitudinally within the housing. The filter device (70) comprises a lattice structure of crossing internal and external elongated elements (18, 20). The lattice structure comprises an arrangement of pores (22), and the external elongated elements (20) are presented outwardly of the filter device (70) with respect to the plane of the pores, thereby to provide ribs on the exterior of the lattice which define a shaped channel that will act as a first level filter for larger particles. The external elongated elements are shaped and arranged to provide one or more additional filter levels for smaller particles in advance of said pores, through which yet even smaller particles may pass.

An apparatus for separating out and removing screenings from wastewater includes a screening device having a screen surface through which the wastewater flows during operation of the screening device and screenings carried along in the wastewater are at least intermittently retained. The apparatus includes a sensor and a controller. The sensor monitors the screenings in the area upstream from the screen surface and/or in the area of the screen surface. The controller outputs a message when the screenings have one or several properties which have been defined and have been recognized by the sensor. In addition, a method for operating the apparatus and a system including the apparatus are provided.

A grid bar for a screen grid of a screen includes a multiple number of grid bars arranged next to each other and spaced apart from each other, which serves the purpose of separating screening material from a flowing liquid, such as wastewater flowing in a sewer channel. The grid bar includes a plastic reinforced with fibers, whereas at least a part of the fibers extend in a longitudinal direction of the grid bar. A screen includes such a screen grid.

A screening device for separating out and removing contaminants from wastewater includes two continuous conveyors, which are mounted with clearance from each other. Each has a drive wheel that is guided on a circular path and includes a fixedly situated bar screen, which includes multiple mutually spaced grating bars for removing contaminants from the wastewater. Each bar screen includes multiple clearing elements, which are connected to the conveyor for removing from the bar screen the contaminants that have been separated out by the bar screen. The bar screen forms a fixed screen surface that extends, in the intended installation position of the screening device, essentially in the flow direction of the wastewater reaching the screening device.

A trash rake system with an articulated rake head assembly is provided. The trash rake system includes a main unit, a telescoping boom attached to the main unit, and a rake head assembly attached to an end of the telescoping boom. The rake head assembly includes a base frame, a drive arrangement mounted to the base frame, and a rake head mounted to the drive arrangement. The drive arrangement includes at least one gear arranged to mesh with a rack gear mounted to a rack which is in turn mounted between a fixed member and a movable member of the telescoping boom.

A method for producing a screening device, the method comprising the steps of providing a screening device that includes a plurality of profiled bars and a plurality of bar holder packages associated with the plurality of profiled bars. The plurality of bar holder packages include a plurality of first bar holders and at least one additional bar holder associated with the plurality of first bar holders. The method including the further steps of inserting the plurality of profiled bars parallel to one another into the plurality of bar holder packages, and bending the plurality of bar holder packages such that the plurality of first bar holders and the at least one additional bar holder are bent at the same time.

A product that is an apparatus for removing debris from water containing such debris using a perforated plate, a backer plate, and a skimmer, positioned adjacent the back of the perforated plate to provide a means of removing debris from the perforated plate without scraping the debris from the perforated plate, the skimmer bar and the backer plate being synchronized in their movement.

A padded grating system comprising sheets of multiple composite members secured together with multiple support bars or battens, wherein each composite member preferably consists of an elongated rigid bar with a foam layer adhered thereto which are encapsulated by a PVC or plastic water impervious tube or sleeve that has been heated and shrunk thereon. The sheets are specifically designed to be used in connection with water rides such as the FlowRider and can be modularly installed on site to cover certain drainage areas. The composite members are preferably made by gluing the rigid bars onto a sheet of foam and cutting the foam sheet to form the composite members, and after the tube or sleeve has been heat shrunk around each one, the ends of the composite members are then cut and sealed.

A wire cross-sectional shape for a wire wrap screen provides a primary and secondary gap with a contained circumferential volume in between. The secondary gap extends screen life by taking the place of the primary gap if erosion opens the primary gap and lets the larger solids get past. The closed space between the primary and secondary gaps also has the effect of reducing velocity due to the enlarged volume before the secondary gap is reached while also creating turbulence between the gaps to slow the fluid velocity to protect the secondary gap. All or parts of the wire outer surface can optionally be coated to extend service life.

A system is provided for the dynamic dewatering of any of a variety of sludges, slurries, or waters. A stream of material is treated in a series of distinct operations to release free water, draw off additional water through vacuum, and compress the resultant dewatered solids to result in a substantially dewatered material. One or more open cells are used in vacuum dewatering in continuous dynamic operation. The system may be integrated into a packaged unit that may be installed at a operation site, and maybe operated with multiple like units to increase treatment flowrates.