Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

Abstract: A system meets needs in sludge collection by significantly increasing the flow rate through a header that collects sludge without causing problems in priming. Telescopic pipes stay in a line adjacent to the bottom of a basin and do not float upwardly into or against equipment in the basin. The entire sludge collecting system is in a space of a low-clearance height under the equipment that extends downwardly near the bottom of the basin. The sludge is collected by openings in header pipes, and by at least one bearing opening in an outer pipe, wherein the bearing opening extends to a radial clearance between the telescopic pipes. Flow of the sludge through the radial clearance from the bearing opening is allowed by a bearing that permits relative movement of the outer pipe and the inner pipe to allow traversing of the outer pipe.

Abstract: A baffle controls the normal process flow of liquid in basins of liquid treatment equipment, but releases uncontrolled flow of the liquid caused by events such as seismic events. Methods provide an unbent blank for making such baffle with a hinge member to facilitate the release of the uncontrolled flow. Further methods provide for mounting of the baffle for movement, urging the baffle for the control of the normal process flow, and allowing the uncontrolled flow to overcome the urging and release the uncontrolled flow. Baffle embodiments may be made from exemplary materials such as stainless steel, glass fiber reinforced polyester, pultruded FRP, and redwood.

Abstract: A system meets needs in material collection by significantly increasing the flow rate through a header that collects sludge without causing problems in priming. Telescopic pipes stay in a line adjacent to the bottom of a basin and do not float upwardly into or against equipment in the basin. The entire sludge collecting system is in a space of a low-clearance height H under the equipment that extends downwardly near the bottom of the basin.

Abstract: A system and method meet needs in material collection by significantly increasing the flow rate through a header that collects sludge without causing problems in priming. Telescopic pipes stay in a line adjacent to the bottom of a basin and do not float upwardly into or against equipment in the basin. The entire sludge collecting system is in a space of a low-clearance height H under the equipment that extends downwardly near the bottom of the basin.

Abstract: A travelling screen and screening method minimize reintroducing debris to liquid downstream of a screen while achieving the relatively high efficiency of fixed bar screens. A filter surface is defined by a pair of planar plates, each of the plates having openings through which the liquid but not the debris may flow. A connector between the plates positions the plates relative to each other at a selected fixed angle. The connector formed integrally with each of the plates has the planar plates and the connector formed from one sheet and the connector in the form of a bend. A guide mounts a first travelling screen element adjacent to a second such element at a screen element scraper path with one planar plate of the first screen element being oriented relative to one planar plate of the second screen element to define a linear scraper path. The guide also positions the first and second screen elements adjacent to each other along a debris separation path.

Abstract: A vise having vise members is provided with a vise face on each vise member. The vise faces are opposed and together define an initial vise volume having an open top for receiving loose, wet screenings. The vise faces form jaws moved relative to each other to squeeze the loose, wet screenings, which is a process of enclosing and applying force to the loose, wet screenings to compress the screenings and force the liquid out of or from the material of the screenings. The squeezing makes a loaf volume significantly smaller than the initial volume, and converts the loose wet screenings into a separate dry loaf. A platform has many separate stations. At one station (e.g., receiving & squeezing), a bottom of the trough is sieve-like for draining the liquid from the wet screenings. At another station (e.g., conveying), the bottom of the platform is closed to retain the separate dry loaf of screenings for conveying. At another station (e.g.

Abstract: A programmed bar screen cleaner removes debris from a screen positioned in a channel to prevent the flow of the debris to a liquid treatment. A rake has tines for engaging the screen to move the debris toward and past an upper end of the screen to remove the debris from the screen. Automatic and controllable raking operations are provided to handle the situation in which there is debris jammed in the screen. The jammed debris resists the movement of the rake along the screen, which is sensed via rake motor overloaded, indicated by motor current in excess of a limit. The existence of a jammed rake causes positive release of the rake from the face of the bars, and further movement of the rake is controlled according to the nature of the problem which caused the jamming.

Abstract: Improvements are made to a system in which force is applied to aeration units from only one side of a basin. Part of such force is vector transferred from one end of a beam of the aeration unit to the other end of the beam to move both ends of the beam. The beam supports pipes of the aeration unit. A force transfer module includes one force transfer strand held in a force transfer path between fixed opposite ends of the strand. The force transfer path extends in part along the beam, which is placed in compression. Motion of the one end of the beam resulting from the force is transferred by the single force transfer strand to the opposite end of the beam so that both ends of the beam move relative to the basin under the action of the force.

Abstract: A programmed bar screen cleaner removes debris from a screen positioned in a channel to prevent the flow of the debris to a liquid treatment. A rake has tines for engaging the screen to move the debris toward and past an upper end of the screen to remove the debris from the screen. Automatic and controllable raking operations are provided to handle the situation in which there is debris jammed in the screen. The jammed debris resists the movement of the rake along the screen, which is sensed via rake motor overloaded, indicated by motor current in excess of a limit. The existence of a jammed rake causes positive release of the rake from the face of the bars, and further movement of the rake is controlled according to the nature of the problem which caused the jamming.

Abstract: A universal bar screen cleaner removes debris from a screen positioned in a channel guiding a flow of liquid, solids and the debris. The screen is to prevent the flow of the debris to a liquid treatment basin downstream of the screen. The screen has an upper end, a front side facing the upstream flow and a back side facing the downstream flow. A rake has tines for engaging the screen to move the debris toward and past the upper end of the screen to remove the debris from the screen. A frame supports the rake in a first rake position where the tines are engagable with the screen from the front side, or in a second rake position where the tines are engagable with the screen from the back side.

Abstract: Improvements are made to a system in which force is applied to aeration units from only one side of a basin. Part of such force is vector transferred from one end of a beam of the aeration unit to the other end of the beam to move both ends of the beam. The beam supports pipes of the aeration unit. A force transfer module includes one force transfer strand held in a force transfer path between fixed opposite ends of the strand. The force transfer path extends in part along the beam, which is placed in compression. Motion of the one end of the beam resulting from the force is transferred by the single force transfer strand to the opposite end of the beam so that both ends of the beam move relative to the basin under the action of the force.

Abstract: A header conduit provides an elongated passageway through which waste liquid and sludge ("waste") are guided and enter the conduit along a path that is tangential to at least the inner surface of the conduit which such incoming waste first contacts. When the conduit has an inner surface of circular cross-section, the passageway is elongated enough that the incoming waste enters the conduit along a path tangential to the circular surface. To better assure axial flow of the waste in the conduit to an outlet, the passageway provides both the tangential flow and is at an acute angle to the longitudinal axis of the conduit. The incoming waste is thereby provided with an axial component. In this manner, the passageway assures that the energy and momentum of the incoming waste is helical in direction. The waste previously admitted into the header conduit is urged by the newly entering waste to continue to flow helically in the conduit.

Abstract: Force is applied to aeration units from only one side of a basin. Part of such force is transferred from one end of a beam of the aeration unit to the other end of the beam to move both ends of the beam. The beam supports the pipes of the aeration unit. A force transfer module includes one force transfer strand held in a force transfer path between fixed opposite ends of the strand. The force transfer path extends in part along the beam, which is placed in compression. Motion of the one end of the beam resulting from the force is transferred by the single force transfer strand to the opposite end of the beam so that both ends of the beam move relative to the basin under the action of the force. When the aeration unit uses a many-sided frame to support aeration pipes, many modules are used to transfer the force along the pipes to move the entire frame at one time. A method provides a force transfer strand with first and second opposite ends and a length substantially constant under tension.