An underdrain system for a media pressure vessel has a set of removable pipe sections located between an external header and the bottom of a vessel. Septa extend upwards from the removable pipe sections into the vessel by up to 16 inches. The septa may have diameters of 6 inches or more. The header is attached to the bottoms of the removable pipe sections. Each pipe section, and its associated septum, may be removed individually. To clean the vessel. after media is removed from the vessel the pipe sections are removed sequentially while the header remains otherwise attached to the vessel. While a pipe section is removed. its associated septum is removed so that solids can be removed from the annulus between the septum and the vessel. In this way. media can be cleaned from the annuli without moving the external header or entering the vessel.

An underdrain system for a media pressure vessel has a set of removable pipe sections located between an external header and the bottom of a vessel. Septa extend upwards from the removable pipe sections into the vessel. The header is attached to the bottoms of the removable pipe sections. To clean the vessel, the pipe sections are removed. While a pipe section is removed, its associated septum is removed so that solids can be removed from the annulus between the septum and the vessel. In this way, media can be cleaned from the annuli without moving the external header or entering the vessel. A cleaning mechanism includes an elongated member with a spray nozzle that may be moved within the vessel. The cleaning mechanism may be used to removed media adhered to the walls of the vessel, for example while the septa are removed.

A system and process for removing from an aqueous stream impurities such as grit, particulates, floating debris, suspended solids, turbidity, bacteria, fecal coliform, oil, grease, color, and the like, and for treating an unacceptable biological oxygen demand, chemical oxygen demand, and/or dissolved oxygen by utilizing a treatment system positioned partially in a channel adapted to a flow of the aqueous stream. The treatment system comprises a containment zone for containing the aqueous stream for treatment by at least one of traveling or stationary screen filtration, aeration, anaerobic and/or aerobic digestion, clarification, media filtration, chemical addition, disinfection, pH adjustment, particulate removal, and/or the like. A partition wall is provided to bypass untreated water such as storm water. After passing untreated waste water through the treatment zone, the treated aqueous stream may be recycled for further use or discharged to its desired destination, such as a lake, river, or ocean.

A read circuit for an electrical signal produced by a POSFET device is disclosed which comprises a transconductance amplifier (4) connected at its inverting input to the output of the POSFET device (1), at least one neuron (8a, 8b) connected to the output of said transconductance amplifier, said amplifier being adapted to receive a signal from the POSFET device representative of a force or pressure exerted on it and to produce at its output at least one current signal (I.sub.0, I.sub.0+) representative of such force or pressure, the at least one neuron being adapted to receive said current signal and to produce an output signal (12a, 12b) being a pulse train with frequency proportional to said current signal.

A system and method for removing from an aqueous stream impurities such as grit, particulates, floating debris, suspended solids, turbidity, bacteria, fecal coliform, oil, grease, color, and the like, and for treating an unacceptable biological oxygen demand, chemical oxygen demand, and/or dissolved oxygen by utilizing a treatment system positioned partially in a channel adapted to a flow of the aqueous stream. The treatment system comprises a containment zone for containing the aqueous stream for treatment by at least one of traveling or stationary screen filtration, aeration, anaerobic and/or aerobic digestion, clarification, media filtration, chemical addition, disinfection, pH adjustment, particulate removal, and/or the like. A partition wall is provided to bypass untreated water such as storm water. After passing untreated waste water through the treatment zone, the treated aqueous stream may be recycled for further use or discharged to its desired destination, such as a lake, river, or ocean.

The present document describes a media bed filter for filtering fine particles from a raw liquid flow, the media bed filter comprising: a tank having: a top portion; a bottom portion defining a bottom surface for receiving a media bed, the media bed having a supporting media to be disposed on the bottom surface and a filtering media for covering the supporting media, the top portion of the tank being above the filtering media of the media bed; a raw liquid inlet in fluid communication with a nozzle configuration located in the top portion of the tank for providing the raw liquid flow in the tank in the form of a plurality of jets at a directional velocity substantially equal or greater to a disengagement velocity of the filtering media.

The present document describes a media bed filter for filtering fine particles from a raw liquid flow, the media bed filter comprising: a tank having: a top portion; a bottom portion defining a bottom surface for receiving a media bed, the media bed having a supporting media to be disposed on the bottom surface and a filtering media for covering the supporting media, the top portion of the tank being above the filtering media of the media bed; a raw liquid inlet in fluid communication with a nozzle configuration located in the top portion of the tank for providing the raw liquid flow in the tank in the form of a plurality of jets at a directional velocity substantially equal or greater to a disengagement velocity of the filtering media.

A water filter includes an elongated housing including a first distal portion forming a mouth, a second distal portion forming holes, and a sidewall forming a nozzle that is fluidly coupled to an inner chamber of the elongated housing via a passage. The inner chamber fluidly couples the mouth with: the nozzle in a first configuration; and an external environment via the holes in a second configuration. The water filter includes a substantially spherical structure disposed in the inner chamber. The substantially spherical structure is configured to be forced: toward the mouth in the first configuration; and toward a portion of the inner chamber that is opposite the mouth in the second configuration to create a temporary seal. The elongated housing forms a protrusion that extends into the inner chamber and is configured to prevent the substantially spherical structure from exiting through the mouth.

A water filter includes an elongated housing including a first distal portion forming a mouth, a second distal portion forming holes, and a sidewall forming a nozzle that is fluidly coupled to an inner chamber of the elongated housing via a passage. The inner chamber fluidly couples the mouth with: the nozzle in a first configuration; and an external environment via the holes in a second configuration. The water filter includes a substantially spherical structure disposed in the inner chamber. The substantially spherical structure is configured to be forced: toward the mouth in the first configuration; and toward a portion of the inner chamber that is opposite the mouth in the second configuration to create a temporary seal. The elongated housing forms a protrusion that extends into the inner chamber and is configured to prevent the substantially spherical structure from exiting through the mouth.

System and process for cleaning media in a vessel includes directing a cleaning liquid into the vessel. A fluidizing pump draws the cleaning liquid from the vessel and returns a portion of the cleaning liquid to a fluidizing nozzle that is directed downwardly into the vessel. The fluidizing nozzle discharges the cleaning liquid in a jet stream that contacts the media causing the media to move upwardly in the vessel and become fluidized. The media is continuously fluidized and agitated for a time. In the process, contaminants associated with the media are separated and become contained in the cleaning liquid. During this process, most of the media is confined while within the vessel.