Abstract: The present invention is aimed at treating rainwater in a combined sewer system, while enabling removal of a majority of pollution substances even if a large amount of entering rainwater. The invention relates to a rainwater-treating apparatus in a combined sewer system, said apparatus comprising a plurality of upward flow type high-speed filter vessels each having a layer of a floating filter medium, a common treated water vessel which is located at upper faces of said high-speed filter vessels and is adapted to collect treated water from the high-speed filter vessels, a used wash water vessel which collects used wash water from said high-speed filter vessels, a rainwater inflow channel for distributing the entering rainwater into upper portions of the high speed filter vessels, and rainwater inflow portions for flowing downwardly the rainwater distributed from the rainwater inflow channel under the respective floating filter media of the filter vessels.

Abstract: The present invention provides an apparatus and method for filtering fluids with a compressible filter media within at least a portion of a housing inwardly compressible.

Abstract: In a medical device, a Tx Clock Button is presented on a graphics display overlain with a touch screen which allows an operator to control multiple functions of the medical device. Various parts of Tx Clock Button may be displayed in different colors, and based on the state of treatment at a given time and in response to the operator touching Tx Clock Button, the colors may change to visually indicate a change in state. When the Tx Clock Button is touched for the first time after a new patient has been selected, multiple functions, times, displays, parameters, and alarms of the medical device are initiated. When the Tx Clock Button is touched for the second time, various ones of the multiple functions, times, displays, parameters, and alarms may be suspended. A third touch of the Tx Clock Button may resume the suspended items.

Abstract: A process and system for removing animal processing contaminants and fats, oils, and greases from large volume quantities of waste water. In the process, a waste water stream containing the contaminants is treated with a chemical oxidant, polymer compound and coagulant to create a particle having a diameter greater than 50 microns. Treated waste water is passed through a microfiltration membrane which physically separates the contaminant particle from the waste water. Commercially available microfiltration membranes having a pore size in the range of 0.5 micron to 10 microns may be used. The treated waste water flow rate through the microfiltration membranes can range from at least 200 gallons per square foot of membrane per day (“GFD”) to in excess of 750 GFD. Solids are removed from the membrane surface by periodically backflushing the microfiltration membranes and draining the filtration vessel within which the membranes are located.

Abstract: A process for removing BOD and suspended solids from wastewater without passing through a primary clarifier or secondary aeration tank, the process. During the process, raw sewage wastewater, comprising soluble BOD, insoluble BOD and suspended solids, is piped directly to a deep bed granular filter. The bed depths of deep bed filter are within a range of approximately 2.0 ft to approximately 10.0 ft. The raw sewage wastewater is filtered by filtration through the deep bed filter in which the filter media is a granular media with a size range between approximately 2.0 mm to 10.0 mm. Backwashing the deep bed filter occurs at least once every 48 hours.

Abstract: The present invention refers to an apparatus (11) and a method for milk filtration and filter regeneration. The apparatus comprises a filter vessel (13); a loose filter material (37) housed within the vessel for filtering out contaminants in the milk; and a grid (31) arranged in front of the milk flow outlet to prevent the loose filter material from leaving the vessel. The vessel includes inner walls (15, 17); a milk inlet (21); a milk outlet (23); a cleaning fluid inlet (23) arranged substantially vertically at the lowermost portion of the vessel, through which a cleaning fluid jet can be injected, and a cleaning fluid outlet (21) arranged at the upper portion of the vessel. The lower portions (17) of the inner walls of the vessel form an angle (&agr;) with respect to the horizontal plane, the angle being larger than the angle of repose for the filter material in the cleaning fluid.

Abstract: A filter system employing a modular filter and at least one high rate pre-treatment system for expeditiously and effectively filtering water. The modular filter includes a reservoir housing for containing fluid. A plurality of filter cells are disposed in the reservoir housing for filtering influent passed through the reservoir housing. Each of the plurality of filter cells has at least one layer of media. A moveable backwash assembly is provided for sequentially backwashing the plurality of filter cells. The backwashing procedure is performed on the modular filter system such that while one of the plurality of cells is being backwashed the remaining cells are filtering pre-treated influent processed by the pre-treatment system. The pre-treatment system preferably has a footprint considerably smaller than the footprint of the modular filter.

Abstract: Porous media filters are commonly cleaned by backwashing. Immediately following the backwashing process, a high concentration of contaminant(s) pass through the filter, which is a phenomenon know as filter “ripening” or maturation in the municipal water treatment community. A new process has been invented that can reduce the concentration of contaminants that pass through a filter during “ripening” and is called the extended terminal subfluidization wash (ETSW). ETSW is a new backwashing process for porous media filters that involves using a washwater flow rate below the minimum fluidization velocity of at least some of the filter media grains following the primary cleaning stage of backwashing (e.g., fluidization) for an amount of time sufficient to displace the majority of the water volume in the filter during the overflow portion of the backwashing process.

Abstract: A modular filter system having a mechanism for performing a filter to waste step on the last cell of a multi-cell system following backwashing. A method of operating a modular filter system in which a filter to waste step is performed on the last cell of a multi-cell system after backwashing.

Abstract: A method and apparatus is disclosed for very rapidly cleaning very small, colloidal particles from nuclear reactor water subjected to a high-energy waterjet cutting of metal using metal shot particles for cuffing such as garnet particles with the cutting causing fracturing of the metal shot as well as the cut metal fines into a negatively charged colloidal suspension having a large area. This colloidal suspension causes water turbidity and makes known filtration techniques impractical for rapid removal of such suspensions for recycling to the reactor.

Abstract: The present invention is aimed at treating rainwater in a combined sewer system, while enabling removal of a majority of pollution substances even if a large amount of entering rainwater. The invention relates to a rainwater-treating apparatus in a combined sewer system, said apparatus comprising a plurality of upward flow type high-speed filter vessels each having a layer of a floating filter medium, a common treated water vessel which is located at upper faces of said high-speed filter vessels and is adapted to collect treated water from the high-speed filter vessels, a used wash water vessel which collects used wash water from said high-speed filter vessels, a rainwater inflow channel for distributing the entering rainwater into upper portions of the high speed filter vessels, and rainwater inflow portions for flowing downwardly the rainwater distributed from the rainwater inflow channel under the respective floating filter media of the filter vessels.

Abstract: The present invention provides methods of harvesting rare cells from blood products and/or obtaining products of the rare cells. The method includes contacting a blood product containing rare cells with a porous medium, and selectively retaining rare cells of interest on the porous medium. The porous medium can be contacted with an elution fluid wherein a population of the rare cells is eluted from the porous medium. Rare cells selectively retained on the porous medium can be cultured on the porous medium, and products of the rare cells can be obtained.

Abstract: The present invention provides a floating media biofilter having an economical structure which allows energy efficient and water conserving backwashing of the floating media. The biofilter includes a filter chamber fluidly connected to a charge chamber which is adapted for accumulating air. A trigger device positioned between the charge chamber and filter chamber selectively allows the flow of air from said charge chamber to said filter chamber. An air source is connected to the charge chamber and slowly supplies air thereto. The backwash cycle is initiated by the trigger device allowing air to escape from the charge chamber into the filter chamber and agitate the floating media. Simultaneously, water from the filter chamber flows into the charge chamber. After the trigger device closes, air again accumulates in charge chamber in preparation for another backwash cycle.

Abstract: An apparatus for continuously filtering a suspension includes a filter-medium washer provided with length-adjustable walls.

Abstract: A method and apparatus for removing arsenic from water at point of entry or point of use particularly for residential application. The point of entry system comprises a first stage having a manganese greensand oxidizer to convert arsenite (As+3) present in the water to arsenate (As+5) and a second stage for passing the water through an anion exchange resin. Each stage includes a control head for automatic regeneration at a predetermined frequency. The manganese greensand is regenerated with a solution of potassium permanganate and the anion exchange resin is regenerated with a salt solution. An alternate embodiment for point of use application comprises a manganese greensand oxidizer cartridge to convert arsenite (As+3) to arsenate (As+5) followed by removal of the arsenate (As+5) with a reverse osmosis system.

Abstract: The invention relates to a method and device for the continuous filtration of liquids containing solid matter, in particular for cleaning wastewater, by means of a filter bed consisting of a particulate filtering medium, which is continuously moved through a vertically positioned cylindrical annular space (2) through which the liquid to be filtered continuously flows radially from the interior to the exterior. The particulate filtering medium containing the separated solid matter is continuously tapped from the lower end of the annular space (2), transported to the top, freed of the filtered solid matter and fed back into the annular space (2) at its upper end. With this kind of method and device, to be able to prevent in a better and more simple manner blockages caused by the separated floc of solid matter, the invention provides that as particulate filtering medium a particle mixture is used with a particle-size range comprising two or more particle sizes, ranging from coarse (2.5 mm) to fine (0.

Abstract: A water treatment apparatus provides treatment of water to remove, for example, hydrogen sulfide and iron, dissolved or dispersed in ground water. The system is provided with water from a conventional well and pump and includes a venturi-type aerating device which may be supplied air by a compressor. The air and water mixture are supplied to a first aerating tank through a spray nozzle which reduces the aerated water flow to a mist of fine droplets. A draw tube adjacent the bottom of the first tank provides the water to a treatment tank which is partially filled with a chemically active filtration media. The treatment tank is also equipped with a draw tube which draws off the treated water at the bottom of the tank and provides it to a third, deaerating tank wherein the air separates from the water and is purged to the atmosphere. Reduction of hydrogen sulfide content from 30 ppm to less than 5 ppm has been achieved.

Abstract: A water-based heating or cooling plant incorporating a filtration device and a pipeline network for bleeding water from the heating or cooling plant to the filtration device, the filtration network for bleeding water from the heating or cooling plant to the filtration device, the filtration device having a tank with an upright column of horizontal layers of granulated filtration materials, the densities in the layers increasing from the layer at the top downwardly to the most dense bottom layer, at least one layer being a mechanical layer and at least one layer having a chemically active material to increase the pH value of the water to a magnitude exceeding neutral. The invention includes a method for operating the plant and for backwashing the granulated filtration material.

Abstract: A concurrent backwash distribution apparatus for a filter having a filter tank and a plurality of underdrain laterals includes a baffle positioned in a common main conduit to define an auxiliary flume between the baffle and the underdrain laterals. The auxiliary flume is in fluid communication with the common main conduit and the underdrain laterals. The baffle has at least one flume liquid metering orifice preferably located near the bottom of the baffle so that it may be below a gas/liquid interface in the auxiliary flume during concurrent gas/liquid backwash operations. A flow distribution plate may be positioned between the auxiliary flume and the underdrain laterals, the flow distribution plate having at least one liquid metering orifice and at least one gas metering orifice. The baffle may take one of many forms. The baffle creates an adequate liquid pool in the common main conduit for low velocity flow of backwash liquid while at the same time providing uninhibited flow of backwash gas.

Abstract: A differential pressure monitor measures the pressure at a plurality of heights in a filter bed. A preferred embodiment of the monitor comprises an elongated body, a plurality of pressure sensors located on the elongated body for obtaining the pressure readings, a control apparatus for determining differential pressures from the pressure readings, each differential pressure being the difference in pressure between pressures measured at two different heights in the filter bed, and transmission apparatus to transmit the pressure readings from the pressure sensors to the control apparatus. Methods of monitoring and controlling the performance of a filter bed during filtration and during backwashing also are provided. Two such methods include measuring turbidity levels in a filter bed and obtaining water samples from a filter bed.

Abstract: A filtration unit is provided with a self-cleaning mechanism which backflushes a screening element therein when it becomes blinded by solid material. A reservoir enables a head of screened liquid to be built up above the screening element. Upon blinding of the screening element, a subsequent rise in the pressure at the inlet of the filtration unit is detected by way of a rising fluid level in a vertically extending chamber. The above causes the opening of a discharge valve which enables a discharge flow to rapidly empty the reservoir through the screening element in a reverse direction, thereby clearing the screen. The clearing operation is carried out entirely hydraulically by the action of the screened fluid and thus no brushes, rakes or scraping devices are required.

Abstract: A filtration tank (1) for purification of polluted water includes a chamber (12). Upper and lower filtration screens (20, 22) are supported within the chamber. Filtration particles (18) are confined between the upper and lower screens. Polluted water enters the chamber through an inlet (26), passes through the screens and the filtration particles and exits the chamber through a purified water outlet (28). Periodically, the inlet and outlet are closed and the water in the chamber is drained through a drain outlet (32). Nozzles (42, 45) spray cleaning fluid over the filter particles and screens to dislodge trapped dirt.

Abstract: Apparatus is provided for coalescing microscopic droplets of organic (principally hydrocarbons) that are present with particles in an aqueous stream (primarily water), which avoids frequent shutdowns for backwashing. The system includes two anthracite beds (56, 58, FIG. 2) and apparatus for connecting the beds in series. Most of the time, the stream flows down (60) through the first bed and up (64) through the second bed, and to a separator, while particles (74) accumulate at the top of the first bed. When the particles begin to seriously block flow through the first bed, the flow is reversed for a period while the particles are transferred from the top of the first bed to the top of the second bed. After several minutes, the flow is reversed again, causing particles at the top of the second bed to flow to the separator for removal.

Abstract: A method of degassing biological filters utilizing a backwash system wherein the steps of opening and closing valves are reduced, flow interruption through the filter is minimized, and the process of draining down a downflow filter is eliminated. A preferred method of degassing a plurality of downflow biological filters in a water treatment system comprises the steps of maintaining the influent flow throughout the degassing process, ceasing the effluent flow out of a filter selected to be degassed to prevent draining of the selected filter, introducing a backwash water flow into the bottom, and flushing of the filter until entrapped gases are released out of the filter. The backwash flow is then ceased and the effluent flow is recommenced to return the filter to service. The steps are successively repeated and the backwash pump remains on until all filters are degassed.

Abstract: A method of recovering functional human leukocytes from blood filters used to deplete leukocyte content from leukocyte-containing blood-cell suspensions is provided. More particularly, this method involves isolating leukocytes from filters which have been used to purify red blood cells or platelets in isolation from leukocytes by back-flushing the used filters with a hemolysis solution, such as cold ammonium chloride, and collecting the functional human leukocytes.

Abstract: A differential pressure monitor measures the pressure at a plurality of heights in a filter bed. A preferred embodiment of the monitor comprises an elongated body, a plurality of pressure sensors located on the elongated body for obtaining the pressure readings, a control means for determining differential pressures from the pressure readings, each differential pressure being the difference in pressure between pressures measured at two different heights in the filter bed, and transmission means to transmit the pressure readings from the pressure sensors to the control means. Methods of monitoring and controlling the performance of a filter bed during filtration and during backwashing also are provided. Two such methods include measuring turbidity levels in a filter bed and obtaining water samples from a filter bed.

Abstract: A water filtration technique is designed to maximize the efficient performance of a variety of granular filtration media. The technique maintains the granular filtration media in a compacted state between a perforated outer media container and a perforated inner media container, where the perforated inner media container is a smaller similitude of the perforated outer media container. In the preferred embodiment of the filtration device of the present invention, the perforated outer and inner media containers are substantially spherical. By maintaining the granular filtration media in a static-state throughout filtration, highly efficient filtration is achieved. In contrast, during the backwash function, the normal inward flow is reversed to outward radial flow and granular filtration media is agitated, fluidized and quickly and vigorously cleaned. A plurality of high-velocity centrally-located water jets create the outward radial flow during backwashing.

Abstract: A cooling tower water treatment system removes contaminants include chlorine, calcium carbonate as calcite, and microorganisms from water in the system with redox media in a fluidized bed. The treatment system includes a treatment bed, in the form of a column, having a reaction chamber of a first diameter and a retention chamber of a second diameter, the second diameter being greater than the first diameter. Redox media, in the reaction chamber, is fluidized by water flowing in a direction countercurrent to gravity and is held in place, without the use of screens or filters, by a reduction in flow rate of the fluidizing media resulting from the larger diameter of the retention chamber. Preferably, the treatment system includes a physical filtration unit, such as an automatic backwashing sand filter, to prevent entry of particulates and scale into the reaction chamber.

Abstract: Apparatus for treating a liquid containing suspended solids comprising a clarifying vessel and a number of filters positioned around the periphery of the clarifying vessel for receiving and filtering liquid from the clarifier. A filter may be backwashed by isolating that filter, filling the other filter cells with clarified liquid and draining them into the isolated cell to remove filter media contaminants.

Abstract: A hemodialysis machine is described that has an extracorporeal circuit that is primed automatically prior to connection of the patient to the machine. The priming is accomplished by filling the extracorporeal circuit with a priming fluid, such as a saline or dialysate solution or blood. The blood pump and clamps in the arterial and venous lines are operated by a control system in a fashion to create multiple brief pressure pulses in the priming fluid. The pressure pulses shear air bubbles present on the blood side of the dialyzer membrane off the membrane. The blood pump is then operated to clear the bubbles from the dialyzer compartment where they are removed from the priming fluid by conventional bubble trap apparatus.

Abstract: The invention relates to a method and a conditioning system for regenerating replacement filters, a stackable transport container for use in such a system, and a replacement filter for regeneration by such a method. The following method steps are proposed for this purpose: removal of fluid residues from the replacement filter, flushing the filter element with a flushing agent opposite the direction of flow through the replacement filter when in use, removing the flushing medium residue from the replacement filter, measuring the flow resistance of the filter element, and comparing the measured flow resistance with one or more preset limit values.

Abstract: A backwash sealing shoe is provided for a filtration system including a tank having an undivided filtration bed and a plurality of side-by-side headers within the bed, each header in communication with a respective port in a wall of the tank. The sealing shoe includes a hydraulic section including an opening surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one of the ports; and at least one blocking section adjacent the hydraulic section on one side thereof and including a plate surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one adjacent port to thereby block flow from the tank through at least one adjacent port during a backwash operation.

Abstract: A control system for controlling a backwash operation in normal and high flow operating modes is provided in a traveling bridge filter having a filter basin; a filter media bed; a filtrate channel; a traveling bridge adapted to traverse the filter basin with a backwash hood suspended therefrom; a programmable logic controller; a reference sensor and five spaced water level sensors. The controller and the sensors control the backwash operation by sensor functions which differ between the normal and high flow operating modes.

Abstract: An automatically-regulated, self-flushing method of filtering a liquid suspension includes passing the suspension through a granular filter material. The flow of suspension is halted to relieve the pressure in the system, so facilitating the settling of the removed particles down the filter. Further settling of the particles may be achieved by passing an airstream through the filter material. A reverse flow of the filtrate then effects a backwashing action on the filter material so that further settling of the particles is encouraged. The filter material may be contained in a drain passage which follows a generally sinuous path. The drain passage may serve a waste landfill site in which toxic, hazardous or domestic waste is disposed.

Abstract: A method is described for priming a dialyzer placed in an extracorporeal circuit of a hemodialysis machine in situ. The method comprises the steps of substantially filling the extracorporeal circuit and the blood side of the dialyzer with fluid (such as dialysate, RO water, saline, etc.), and inducing pressure pulses in the fluid. The pressure pulses cause air bubbles from the blood side of the dialyzer to be sheared off the dialyzer membrane. The air bubbles are then conducted from the dialyzer and removed from the extracorporeal circuit. Backfiltering of fluid across the dialyzer from the dialysate circuit into the extracorporeal circuit is performed in synchrony with the pressure pulses to assist in the shearing off of air bubbles from the blood side of the dialyzer membrane.

Abstract: A novel process for treating a fluid is disclosed. Generally, the process utilizes a novel fluidized bed reactor and down flow filter. The process includes filling the reactor, and thereafter fluidizing the media bed contained therein. A catalyst is added, and the entire batch fluid is allowed to react with the catalyst. After appropriate settling of the media bed, the batch fluid is recycled. A filtration step is then included and appropriate disposition of the collected filtrate may be effected.

Abstract: A traveling bridge filtration system includes a tank configured to include a plurality of side-by-side filter cells all extending longitudinally in a first direction, and a common filtrate channel extending longitudinally in a second direction perpendicular to the first direction. Each filter cell has an outlet extending through an interior wall of the tank thereby establishing fluid communication with the filtrate channel. A traveling bridge is mounted atop the tank and movable from cell to cell in the second direction. A backwash pump, having an inlet and a discharge pipe connected to a backwash shoe, is pivotally suspended from the bridge within the filtrate channel and run continuously. A fluid operated bellows is used for moving the backwash shoe selectively into sealing engagement with a tank wall surface surrounding one of the filter cell outlets in response to back pressure developed in the backwash pump discharge pipe. Fluid pressure to the bellows actuator is controlled by a pair of solenoids.

Abstract: A traveling bridge filtration system includes a tank configured to include a plurality of side-by-side filter cells all extending longitudinally in a first direction, and a common filtrate channel extending longitudinally in a second direction perpendicular to the first direction. Each filter cell has an outlet extending through an interior wall of the tank thereby establishing fluid communication with the filtrate channel. A traveling bridge is mounted atop the tank and movable from cell to cell in the second direction. A backwash pump, having an inlet and a discharge pipe connected to a backwash shoe, is pivotally suspended from the bridge within the filtrate channel. A fluid operated bellows is used for moving the backwash shoe selectively into sealing engagement with a tank wall surface surrounding one of the filter cell outlets in response to actuation of the backwash pump. A related method of use is also disclosed.

Abstract: A method of cleaning a filtration tank having a plurality of side-by-side gravity flow filter cells, each having an outlet port in communication with a filtrate channel common to all of the cells in an automatic backwash/rewash system, by subjecting each compartment, sequentially, to a backwashing operation and then a rewashing operation wherein, during backwashing, backwash liquid is pumped through a first of the filter chamber ports to flow upwardly through a first of the compartments in a direction opposite to a normal filtration flow direction, and during rewashing, rewash liquid is drawn downwardly through the first cell in the normal filtration flow direction. For any given cell after a first of the plurality of cells, utilizing at least a portion of the rewash liquid from a rearwardly adjacent filter cell is used as backwash liquid in the given cell.

Abstract: A rapid gravity downflow filtration system applicable to a bank of several filters in which filtered water for backwashing is stored at a relatively high level in a common washwater storage compartment serving all filters and in which the filtered water for backwashing is delivered to it's storage by gravity using the surplus operating head available at the beginning of the filter operating cycle for the purpose thereby entirely eliminating the necessity for powered motivation of backwash water flow during backwashing, or, in alternative filter systems in which the backwash water flow is motivated by displacement with compressed air, reducing the power requirement.

Abstract: A filter for removal of biochemical oxygen demand and suspended solids utilizing multi-layer filtration media. The filter media includes plastic particles, sand, and garnet and is operated under an automatic control condition. Fine filtering is accomplished by a sludge cake which develops at the upstream face of the filter media. For cleaning the filtration media, deposited sludge is removed from the filter bed by backwashing in a short time period at a high strength backwash flow rate.

Abstract: A moving bed filter in which the liquid to be filtered is introduced into an internal chamber centrally disposed in the filter bed. The liquid flows through the filter bed to filtration nozzles which are disposed near the outer periphery of the filter bed. A portion of the filter bed media is continuously removed from a recessed chamber below the floor of the filter bed, transported by gas lift through a lift conduit to a washbox located above the filter bed, and cleaned by a countercurrent flow of the filtrate.

Abstract: A floating media biofilter is provided, comprising a tank having a bottom and a sidewall, the sidewall having a lower portion inwardly sloping toward the bottom. Floating media are present in the tank for forming a media pack when the tank is filled with liquid, and the media are retained by an upper screen positioned in the upper portion of the tank. An inlet line provides nonfiltered liquid to the tank from an aquaculture environment, while an outlet line above the upper screen delivers filtered liquid back to the aquaculture environment. A weir is employed between the upper screen and the outlet line to collect filtered liquid from the media pack. Backwashing is accomplished by a motorized blade system which causes the media to circulate within the tank with substantially no expansion of the media pack. The circulating media loosens filtered matter and sludge entrained therein so that the waste solids can be removed by a sludge line connected to the bottom of the tank.

Abstract: A filter apparatus having a backwash head arranged to up-flow backwash one filter cell at a time, and a scavenging means having a fluid intake head arranged to communicate with at least two cell ports at the same time to downflow scavenge each filter cell the first time when the backwash head is in a position to backwash one filter cell and a second time when the backwash head is in a position to backwash a succeeding filter cell. Turbidity monitoring means having a monitor inlet conduit mounted on the fluid intake head, is arranged for communication with the cell port adjacent the end of the fluid intake head that trails during the backwash run, to monitor turbidity of fluid from each cell port only after the associated filter cell has scavenged at least once.

Abstract: The local reclamation system includes an accumulation tank for a soiled solution. A tank outlet valve selectively allows a flow of the solid soiled solution into the remainder of the system. A blend conduit leads from the outlet valve. An oxidizing supply selectively provides an oxidizing agent to said soiled solution downstream of the outlet valve in the blend conduit. A blend pump receives the soiled solution with oxidizing agent to promote the flow of the soiled solution through the system and a more uniformed disposal of the oxidizing agent throughout the solution. A six stage filter section selectively removes particulate matter. A biologic stage promotes a sterile reclaimed solution and a solution accumulator accumulates and stores the solution. Repeated injections of oxidizing agents occur before filter stage sections and pumps. The reclaimed solution can be reused or discharged without penalty.

Abstract: A method of washing an upflow filter between service runs employs a filter bed having a non-buoyant particulate filter layer through which influent to be filtered is directed in an upward direction, and through which liquid employed in the washing operation is directed in an upflow direction. A two-stage washing operation includes the steps of first directing a combination of air and liquid in an upflow direction through the filter layer with the velocity of the liquid being less than the minimum fluidization velocity of the filter layer, for disrupting only some floc retained in the filter layer during a previous service run, and thereafter directing only liquid in an upflow direction through the filter layer at a velocity less than the minimum fluidization velocity of the filter layer for removing disrupted floc from the filter layer while leaving some floc attached to said particulate media of the filter layer.

Abstract: Methods and systems of the prior art for cleansing a plurality of seriate filter cells in automatic backwash filters by backwashing the cells one at a time with backwash liquid wherein the cleansing operation on the active cell is prevented from moving to a further cell until the contaminant content of the waste liquid issuing from the previous cell reaches a predetermined low level are improved by overriding such prevention even though such content remains too high when a prescribed quantity of waste liquid has issued from the previous cell, e.g., as determined by a timer or fluid meter.

Abstract: A launder and baffle structure, used in association with a filtration tank of the type using granular filtration media, is disclosed which reduces the amount of filtration media lost during a backwashing cycle. The structure of the invention includes an elongated launder, baffle structure system associated with the elongated launder and regulatable air discharge structure associated with the baffle structure system. The structure of the invention is configured to reduce velocity of flow in order to provide settling of filter media from solution and is configured to provide dissipation of air from solution to further enhance quiescence of flow and settling of filter media from solution. The regulatable air discharge system is adjustable to release a selected amount of air from beneath the baffle system in order to regulate turbulence and thereby facilitate quiescence of flow.

Abstract: The present invention comprises apparatus and a method of automatically controlling the permeability of filter beds. In particular, this invention directs itself to filter beds or tanks that are divided into a plurality of contiguous compartments or cells, each compartment containing a filtering media substrate, which substrate is cleansed or backwashed, periodically, when necessary, by a traveling bridge backwash mechanism. The duration and frequency of backwashing is automatically controlled to maintain a desired overall permeability and throughput performance of the filter bed. Permeability control is dynamic to maintain optimum performance under all conditions, i.e. changing in response to fluctuating filter bed hydraulic or solids loading rates.

Abstract: A launder and baffle structure, used in association with a filtration tank of the type using granular filter media, is disclosed which reduces the amount of filter media lost during a backwashing cycle. The structure of the invention includes an elongated launder, sloping baffle structure associated with the elongated launder and air discharge structure associated with the sloping baffle structure which releases air from beneath the sloping baffle structure, the air having been dissipated from the fluid. The structure of the invention is configured to reduce velocity of flow in order to provide settling of filter media from solution, is configured to provide dissipation of air from solution to further enhance quiescence of flow and settling of filter media from solution, and directs fluid flow away from the launder. The structure of the invention further includes a wing baffle for dissipating velocity in the fluid.