Abstract: Disclosed is a fresh water generator for fresh water production, which is effective to prevent a membrane life from becoming worse by suppressing the load on the membrane of a second semi-permeable membrane treatment facility when the concentrated water produced by the treatment of a first semi-permeable membrane treatment facility, and water to be treated with different osmotic pressure there from are mixed and treated with the second semi-permeable membrane treatment facility by the fresh water generator which comprises a means for storing the concentrated water produced from the first semi-permeable membrane treatment facility and water (B) to be treated, which is separately supplied in a storage tank A and a storage tank B in such a manner that the flow rate (mixture ratio) of the concentrated water to the water (B) to be treated is maintained constant, and supplying the concentrated water and the water (B) to be treated from each of the storage tanks to the second semi-permeable membrane treatment facili

Abstract: Separation processes using osmotically driven membrane systems are disclosed generally involving the extraction of solvent from a first solution to concentrate solute by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources. Pre-treatment and post-treatment may also enhance the osmotically driven membrane processes.

Abstract: An osmotic power generation system and method for generating osmotic power includes a membrane chamber having a semi-permeable membrane therein defining a first portion and a second portion therein. The system also includes a first pump communicating a first fluid to the first portion and a second pump communicating a second fluid to the second portion. The second fluid has higher total dissolved solids than the first fluid. A second portion energy recovery device is in fluid communication with the second portion. A power generator is in communication with the second portion energy recovery device generating electrical power in response to the second portion energy recovery device and the pressure in the second portion.

Abstract: The invention relates to a method for enriching a homogenous catalyst from a process flow comprising said homogenous catalyst as a component, wherein the process flow is conducted over at least one membrane and wherein the membrane wholly or partially comprises a polymer that has planar polymer units connected to one another via a rigid link and wherein the linker is contorted, such that at least one planar polymer unit is connected to at least one second planar polymer unit via the link, in a non-co-planar arrangement. The invention furthermore relates to a method for producing tridecanal.

Abstract: The invention relates to a filter assembly for membrane filtration—of liquids, and more in particular a spiral wound filter assembly with improved filtration performance. Provided is a spiral wound filter assembly comprising a permeate channel (5; 305, 325) for transporting permeate to the permeate outlet (12), said permeate channel being provided with at least one flow restriction (13; 113, 120; 213; 333) in form of check or control valves or ridges, for increasing the pressure in at least part of the permeate channel. The invention further relates to an apparatus comprising such a filter assembly, and to methods for using this apparatus.

Abstract: A separation apparatus using a membrane for diafiltration, which provides precise fractionation of a target substance by monitoring and regulating permeability of the target substance based on measurement values and analytical values indicating separation status, such as physical values and concentration of a permeate liquid, a circulating liquid and an internal circulating liquid in a membrane device. A diafiltration process including adding a cleaning liquid to an treating liquid which contains multiple target substances and extracting a target substance into the permeate liquid supplied from a membrane separation apparatus to fractionate the target substance from other target substances remaining in a residual liquid.

Abstract: A method of filtering a feed liquid in a membrane filtration assembly is provided comprising introducing feed liquid to be treated into a filtration chamber of a membrane filtration system including a membrane module having one or more permeable hollow membranes, the module being located in the filtration chamber, and the filtration chamber having an open upper end located above an upper header of the membrane module and a closed lower end, and feed tank surrounding the filtration chamber. The feed tank may be configured to provide the feed liquid through the open upper end of the filtration chamber, and the feed liquid may be applied to the surface of the membranes within the membrane module and withdrawn from the lumens of the membranes as filtrate.

Abstract: A system for ultrafiltration employs a crossflow filtration module for extracting a fraction from a sample fluid (e.g., blood) and a recirculating permeate loop to produce a concurrent permeate flow through the filtration module to maintain a positive transmembrane pressure at all points of the crossflow filter. Permeate in the recirculating loop is enriched by a processing module and stabilized by removing an enriched fraction thereof. In an embodiment, the enriched fraction is concentrated plasma that is returned to a patient.

Abstract: In a process for testing filters (4) and (13) of treatment fluid of a hemodiafiltration apparatus (1), each filter has a wet semipermeable membrane (5, 14) which separates a gas-filled first chamber (6 and 15) from a liquid-filled second chamber (7 and 16). The first chambers are pressurised by a pump (19) supplying air, while the second chambers are placed in depression by a drainage pump (17) of used dialysis fluid. A first closed system is formed which includes the first chambers and a second closed system is formed which includes the second chambers. Two pressure gauges (P1 and P2) monitor the pressure in the two closed systems for a predetermined time. The monitoring provides indications relating to the filter integrity.

Abstract: Apparatus and methods are provided for removing solids from wastewater. The apparatus may include a dissolved solids removal system including a first membrane stack for removing a first portion of dissolved solids from wastewater, the first membrane stack having a first rejection rate and including at least one first membrane having a first operating pressure rating. A first solution unit may be included downstream of the at least one first membrane, the first solution unit being configured to maintain a differential pressure over the at least one first membrane below the first operating pressure rating. The dissolved solids removal system may also include a final membrane stack for removing a final portion of dissolved solids from the wastewater, the final membrane stack being located downstream of the first membrane stack and having a final rejection rate higher than the first rejection rate.

Abstract: An apparatus, for use with a reverse osmosis system comprising a feed input, a concentrate output, and a permeate output, includes (i) at least one pressure sensor operative to measure a pressure of at least the permeate output of the reverse osmosis system and to generate a signal indicative of the pressure of at least the permeate output of the reverse osmosis system and (ii) at least one controller operative to adjust a speed of at least a first pumping mechanism based at least in part on the signal indicative of the pressure of at least the permeate output of the reverse osmosis system. The first pumping mechanism comprises at least one of: (i) a fluid input coupled to at least the permeate output of the reverse osmosis system; and (ii) a fluid output coupled to at least the feed input of the reverse osmosis system.

Abstract: This invention relates to a process for producing a product stream with improved reduction of Conradson Carbon Residue (“CCR”) and a reduced average boiling point from a heavy hydrocarbon feedstream utilizing a high-pressure, low-energy separation process. The invention may be utilized to reduce the CCR content and reduce the average boiling point in heavy hydrocarbon feedstreams, such as whole crudes, topped crudes, synthetic crude blends, shale oils, bitumen, oil from tar sands, atmospheric resids, vacuum resids, or other heavy hydrocarbon streams. This invention also results in a process with an improved CCR separation efficiency while maintaining permeate flux rates.

Abstract: Systems and methods of controlling fouling during a filtration procedure are described. A plasmapheresis method includes accepting a selection of a plasma flow rate and predicting an estimated procedure end time based at least partially on a plasma collection target volume. The method also includes flowing blood past a membrane and changing a plasma flow rate until the selected plasma flow rate through the membrane is achieved. The method also includes determining an acceptable rate of pressure change with time for respective times to the estimated procedure end time, the acceptable fouling rate limit being associated with a system pressure and adjusting the plasma flow rate based on the determined acceptable rate of pressure change with time.

Abstract: A dialysis machine method includes in an embodiment applying a pneumatic closing pressure to a first valve chamber and arranging a compliance chamber to flex and absorb energy from the pneumatic closing pressure so as to tend to prevent the pneumatic closing pressure from opening an existing closure of a second valve chamber.

Abstract: An artificial kidney that regenerates dialysate includes: a catheter having an inflow lumen and an outflow lumen for communication with a peritoneal cavity of a patient; a fluid circuit in fluid communication with the catheter for circulating dialysate into, through and out of the peritoneal cavity; a pump configured to circulate the dialysate; a cleaning cartridge coupled to the fluid circuit for removing solutes from the dialysate, including a therapeutically effective amount of urea from the dialysate as the dialysate circulates along the fluid circuit; and wherein the fluid circuit is configured to receive a volume of ultrafilterate removed from the patient, such that the pump can mix the ultrafiltrate volume with the dialysate to an increase an overall therapy fluid volume.

Abstract: Filtration processes and systems are provided for the separation of a filterable fluid stream by a filtration membrane module with uniform transmembrane pressure and flux along the membrane and internal control of membrane fouling via intermittent periodic reduction of the pressure differential between the permeate and retentate sides of the membrane and/or backwashing cycles during separation, recovery, and/or purification of proteins, peptides, nucleic acids, biologically produced polymers and other compounds or materials from aqueous fluids.

Abstract: A microfluidic device for increasing convective clearance of particles from a liquid is provided. A network of first channels can be separated from a network of second channels by a membrane. The network of second channels can include a pressurizing feature to create a high pressure at an upstream portion of the second channels and a low pressure at a downstream portion of the second channels. Liquid containing an analyte can be introduced in the network of first channels. Filtrate can be flowed through the pressurizing feature in the second channels, such that the pressure difference in between the first and second channels causes at least some of the analyte in the first liquid is transported into the second channels through the membrane.

Abstract: Technologies are generally described for a gas filtration device including an array of parallel carbon nanotubes. The carbon nanotubes may extend between first and second substrates, and the ends of the carbon nanotubes may be embedded in the substrates and cut to expose openings at each end of the carbon nanotubes. The carbon nanotubes may be composed from a graphene membrane which may be perforated with a plurality of discrete pores of a selected size for enabling one or more molecules to pass through the pores. A fluid mixture including two or more molecules for filtering may be directed through the first openings of the array of nanotubes, and the fluid mixture may be filtered by enabling smaller molecules to pass through the discrete pores of the graphene membrane walls of the carbon nanotubes to produce in a filtrate fraction including the smaller molecules and a retentate fraction including larger molecules.

Abstract: Plant for desalinating water of a water supply system, which comprises one or more tanks for accumulating water (2) in an immiscible manner, in order to store a softened supply thereof, provided with a first inlet connection (3) and with a first outlet connection (4) respectively connected to a feeding pipe (5) connected to the water supply system (50) and to an extraction pipe (6) for supplying users. The plant (1) also comprises a filtering unit (10) for water softening, for example obtained with a flow-through condenser (10?) or with a reverse osmosis membrane filter (10?), connected in parallel to the tank (2) with second inlet connection (1 1) and second outlet connection (12) respectively hydraulically connected to the first inlet connection (3) and to the first outlet connection (4) of the tank (2).

Abstract: A reverse osmosis system and method of operating the same includes a first pump receiving feed fluid at a first pressure and increasingly pressurizing the feed fluid to a second pressure higher than the first pressure. A membrane housing having an inlet, a membrane, a permeate outlet and a brine outlet. The inlet receiving feed fluid. A hydraulic energy management integration system (HEMI) having a turbine portion, a pump portion and a motor. The brine outlet fluid is in fluid communication with the turbine portion. The reverse osmosis system also includes a second pump and a controller controlling the motor to retard rotation of the HEMI while the first pump increasingly pressurizes the feed fluid to the second pressure.

Abstract: A system and method for processing samples. The system can include a loading chamber, a detection chamber positioned in fluid communication with the loading chamber, and a fluid path defined at least partially by the loading chamber and the detection chamber. The system can further include a filter positioned such that at least one of its inlet and its outlet is positioned in the fluid path. The method can include positioning a sample in the loading chamber, filtering the sample in the fluid path to form a concentrated sample and a filtrate, removing the filtrate from the fluid path at a location upstream of the detection chamber, moving at least a portion of the concentrated sample in the fluid path to the detection chamber, and analyzing at least a portion of the concentrated sample in the detection chamber for an analyte of interest.

Abstract: A method of enhancing flux of tailings settling pond water from an oil sands process through a membrane separation system and purifying the water comprising is disclosed. The process comprises the following steps: (a) treating the water with an effective amount of one or more water-soluble cationic polymers, amphoteric polymers, zwitterionic polymers, or a combination thereof; (b) passing the treated water through a membrane separation system; and (c) optionally, passing the permeate from step (b) through an additional membrane separation system.

Abstract: A system and method utilizing non-invasive fluid volume or fluid weight monitoring to facilitate mixing of therapeutic fluid components during the preparation of therapeutic fluid for dialysis is described. A therapeutic fluid source is provided in cooperative engagement with a weight measuring device which monitors the fluid volume or fluid weight of the therapeutic fluid in the therapeutic fluid source. Peristaltic pumps are configured to pump therapeutic fluid between a conventional dialyzer and the therapeutic fluid source. The weight measuring device is engaged by a control scheme programmed to operate the pumps. The control scheme includes a feedback loop from the weight measuring device to the pumps to facilitate control of the transmembrane pressure at the dialyzer without measuring TMP. System and methods for priming, ultrafiltration and backflush are also described.

Abstract: A water softening system includes apparatus and process that recycles a substantial percentage of the brine. This system conventionally includes a brine tank and a softening tank through which hard water from a source passes during normal operation. During the regeneration cycle, the brine solution in the brine tank passes through the softening tank acquiring hardness ions, and then through a nanofilter that passes a much higher proportion of the brine ions than the hardness ions. The hardness ions flow from the upstream end of the nanofilter into a drain. The liquid passing through the nanofilter contains salt that returns to the brine tank for reuse. A preferred embodiment includes a pump to force the brine solution through the nanofilter and a throttling valve connecting the upstream side of the nanofilter to a drain, and through which the hardness ions flow.

Abstract: In one general aspect, an instrument for measuring characteristics of particles suspended in a fluid is disclosed. It includes a closed wall surface defining a fractionation channel having a input opening, an output opening, and a flow axis that spans downstream from the input opening for the channel to the output opening. A force application subsystem has a force application output oriented perpendicular to at least part of the flow axis of the fractionation channel. A particle characteristic measurement subsystem is located hydraulically downstream from at least a portion of the closed wall surface defining the fractionation channel, and includes a sensor positioned to sense a property of the suspended particles in the potential measurement subsystem as well as a signal output responsive to the sensor.

Abstract: A wafer-shaped hollow fiber module adapted for in-line use in a piping system. The piping system may include two standard bolted flange connections, and at least one wafer-shaped hollow fiber module sealed between the two standard bolted flange connections. The wafer shaped hollow fiber module includes: a cylindrical housing having an open end and a closed end having a first sealing surface and an inlet port; at least one side port through the cylindrical housing; an end cap united to the open end having a second sealing surface and an outlet port.

Abstract: A method for treating an organic waste, in which the organic waste is pressurized and continuously supplied to a high temperature and pressure treatment apparatus to produce a slurried material by blowing steam into the organic waste to cause a reaction while heating, pressurizing and agitating. The slurried material is dehydrated to produce a separated liquid product and a separated solid product. The separated solid product includes sufficient combustible content to produce a fuel product. The separated liquid product is purified.

Abstract: A method comprising providing a power train comprising a plurality of cells, each cell forming a hydraulic loop; producing a power train cycle comprising a controlled concentration-pressure loop wherein the concentration field: (a) osmotically induces a continuous and constant flow rate of substantially salt-free permeate flux throughout the power train; (b) maintains a salt concentration difference across the semipermeable membrane shared by the adjacent cells in the plurality of cells; (c) defines a salt concentration ratio within each cell that ensures a net positive power generation; and, (d) discharges the concentrated brine at the opposing end cell; and operating the power train under conditions effective to generate net positive power at an efficiency of 35% or more.

Abstract: A membrane sensor for detecting fouling, the membrane sensor comprising a first chamber having an inlet and an outlet; a second chamber having an outlet; only one membrane, the membrane being disposed between the first chamber and the second chamber for allowing fluid to permeate the membrane from the first chamber to the second chamber; a first pressure transducer configured for obtaining a first pressure upstream of the membrane; a second pressure transducer configured for obtaining a second pressure downstream of the membrane; and a resistance regulator configured for adjusting the second pressure.

Abstract: The present invention relates to a membrane separation method and a relevant equipment, in particular to a method and an equipment for membrane separation utilizing concentration polarization during membrane filtration process, especially, to a concentration process and equipment and a drawer special for drawing a concentration polarization layer. The direct removal of the concentration polarization layer from membrane surface not only decreases the adverse influence of concentration polarization on membrane separation but also obtains concentrated retention components, thereby significantly improving the ability to maintain membrane flux, solving the twinborn problems concerning concentration polarization and membrane fouling during the membrane separation process, and achieving a high-efficiency concentration for retention components.

Abstract: This invention relates to a composition comprising water and at least one ionic liquid, and also to devices capable of executing an absorption cycle using such compositions as a refrigerant pair. This invention also provides a method of cooling using an absorption cycle comprising water as the refrigerant and at least one ionic liquid as the absorbent. The present invention also provides a method of heating using an absorption cycle comprising water as the refrigerant and at least one ionic liquid.

Abstract: This invention relates to dialysis systems and methods. In some implementations, a method includes applying vacuum pressure to a device of a dialysis system, and then determining, based on a detected fluid level or measured pressure, whether the device is functioning properly.

Abstract: A system and method for balancing flows of renal replacement fluid is disclosed. The method uses pressure controls and pressure sensing devices to more precisely meter and balance the flow of fresh dialysate and spent dialysate. The balancing system may use one or two balancing devices, such as a balance tube, a tortuous path, or a balance chamber.

Abstract: A fresh water producing apparatus for producing fresh water from raw water containing solutes is disclosed. The fresh water producing apparatus comprises a first semipermeable membrane unit and a second semipermeable membrane unit. A first raw water supply line for supplying the raw water is connected to the first semipermeable membrane unit. A second raw water supply line for supplying the raw water is connected to the second semipermeable membrane unit. The first semipermeable membrane unit and the second semipermeable membrane unit are connected by a concentrated water line for supplying concentrated water of the first semipermeable membrane unit to the second semipermeable membrane unit.

Abstract: In a method for converting fluctuating energy into a stable energy supply, the fluctuating energy is derived from the group of solar energy, wind power, waves or water currents, this energy being delivered to a first pump being integrated in a pressure circuit for delivering stable energy and the pressure circuit comprising a pressure amplifier with a double-cone device being driven by the liquid flow circulated by the first pump. This allows the stabilization of fluctuating energy to be used e.g. in desalination plants without supplemental storage energy and without reverting to electric current conversion.

Abstract: A method of treating a liquid. The method comprises providing a feed liquid comprising at least one solvent and at least one solute to a first side of a membrane. A single-phase draw solution comprising at least one of an aminium salt, an amidinium salt, and a guanidinium salt is provided to a second side of the membrane. The at least one solvent is osmosed across the membrane and into the single-phase draw solution to form a diluted single-phase draw solution. At least one of CO2, CS2, and COS is removed from the diluted single-phase draw solution to form a first multiple-phase solution comprising a first liquid phase comprising the at least one solvent, and a second liquid phase comprising at least one of an amine compound, an amidine compound, and a guanidine compound. A liquid purification system is also described.

Abstract: Disclosed is an economical process for the purification of water containing soluble and sparingly soluble inorganic compounds using single-stage or two-stage membrane processes that integrate membrane water purification with chemical precipitation softening and residual hardness and silica removal from the membrane concentrates using ion exchange resins and silica sequestering media, respectively.

Abstract: A method is provided for producing fresh water, the method including feeding raw water to a semipermeable membrane to obtain fresh water, in which water having a solute concentration different from that of the raw water is fed and mixed with the raw water according to changes of a flow rate of fresh water of the semipermeable membrane unit and/or operating pressure of the semipermeable membrane unit.

Abstract: A method is provided for precisely predicting the temporal variation of a membranous filtration resistance, a transmembrane pressure, a membranous filtration flowrate, or a membranous filtration flowrate as occurs in filtrating a liquid with a membrane, in a membranous filtration method wherein the liquid is filtrated by the separation membrane with the transmembrane pressure as a driving force. The method includes calculating: a constituent component quantity value of the liquid that attaches on a surface of the separation membrane at a time t+?t; a constituent component quantity value of the liquid that exists in pores of the separation membrane; a consolidation degree of a constituent component of the liquid that attaches on the separation membrane surface; a membranous filtration resistance value; a transmembrane pressure value; and a membranous filtration flowrate value.

Abstract: A field flow fractionator to separate particles contained within an injected sample aliquot is described. As required, said fractionator may be used to capture, for subsequent removal, specific predefined classes of such particles. Based upon the cross flow or asymmetric flow field flow fractionators, the fractionator disclosed contains means to vary the applied transverse flows at a plurality of locations along the length of its separating channel. One embodiment utilizes a plurality of separated compartments, each lying below a distinct and corresponding membrane supporting permeable frit segment, are provided individual means to control the localized flow through the membrane section thereabove. A corresponding concentric compartment implementation achieves the same type of compartmentalized cross flow when integrated with a hollow fiber fractionator.

Abstract: A wafer-shaped hollow fiber module adapted for in-line use in a piping system. The piping system may include two standard bolted flange connections, and at least one wafer-shaped hollow fiber module sealed between the two standard bolted flange connections. The wafer shaped hollow fiber module includes: a cylindrical housing having an open end and a closed end having a first sealing surface and an inlet port; at least one side port through the cylindrical housing; an end cap united to the open end having a second sealing surface and an outlet port.

Abstract: The present invention generally relates to a filtration system having one or more apparatuses for filtering gases, liquids, or fluids (e.g., water) to remove particulate matter, and methods of making and using the apparatus. More particularly, embodiments relate to apparatuses and methods for applying centrifugal force(s) to push a fluid or gas to be filtered through a porous membrane or filter within the apparatus to separate particulate matter therefrom. The present invention takes advantage of the Coriolis effect within a cylindrical filter radiating out from a rotating central body. The filtration apparatus provides an energy efficient system for microfiltration (or other filtration process) to remove contaminants from gases and fluids, such as waste water.

Abstract: Separation processes using engineered osmosis are disclosed generally involving the extraction of solvent from a first solution to concentrate solute by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources.

Abstract: Systems and methods of controlling fouling during a filtration procedure are described. A plasmapheresis method includes accepting a selection of a plasma flow rate and predicting an estimated procedure end time based at least partially on a plasma collection target volume. The method also includes flowing blood past a membrane and changing a plasma flow rate until the selected plasma flow rate through the membrane is achieved. The method also includes determining an acceptable rate of pressure change with time for respective times to the estimated procedure end time, the acceptable fouling rate limit being associated with a system pressure and adjusting the plasma flow rate based on the determined acceptable rate of pressure change with time.

Abstract: Separation processes using engineered osmosis are disclosed generally involving the extraction of solvent from a first solution to concentrate solute by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources.

Abstract: A method of backwashing a membrane filtration module (4), said module (4) including one or more membranes (5) located in a feed-containing vessel (3), the membranes (5) having a permeable wall which is subjected to a filtration operation wherein feed containing contaminant matter is applied to one side of the membrane wall and filtrate is withdrawn from the other side of the membrane wall, the method including: removing liquid from the feed-containing vessel (3) until the level of liquid in the feed-containing vessel (3) falls to a first level (L2) below an upper level of the membranes; suspending the filtration operation; performing a liquid backwash of the membrane wall until liquid level within the feed-containing vessel (3) rises to a second predetermined level (L1) above said first level; aerating the membrane surface with gas bubbles to dislodge fouling materials therefrom; performing a sweep or drain down of the feed-containing vessel (3) to remove the liquid containing the dislodged contaminant matter

Abstract: Separation processes using forward osmosis are disclosed generally involving the extraction of a solvent from a first solution to concentrate a solute therein by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane. One or both of the solute and solvent may be a desired product. By manipulating the equilibrium of the soluble and insoluble species of solute within the second solution, a saturated second solution can be used to generate osmotic pressure on the first solution. The various species of solute within the second solution can be recovered and recycled through the process to affect the changes in equilibrium and eliminate waste products. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources.

Abstract: The present invention relates to a membrane separation method and a relevant equipment, in particular to a method and an equipment for membrane separation utilizing concentration polarization during membrane filtration process, especially, to a concentration process and equipment and a drawer special for drawing a concentration polarization layer. The direct removal of the concentration polarization layer from membrane surface not only decreases the adverse influence of concentration polarization on membrane separation but also obtains concentrated retention components, thereby significantly improving the ability to maintain membrane flux, solving the twinborn problems concerning concentration polarization and membrane fouling during the membrane separation process, and achieving a high-efficiency concentration for retention components.

Abstract: An aquarium filtration system with enhanced features comprising a continuous flow of filtered and processed water as well as a continuous drain system is herein disclosed. In such a manner, the water is continually changed over time, thus minimizing required emptying and/or cleaning. Additionally the system holds and maintains the desired pH level and water hardness, while controlling ammonia and nitrite levels. A filter on the incoming water line removes chlorine and other chemicals before the water passes onto the aquarium. The system works in conjunction with a conventional automatic water level controller. Automatic check valves control water flow and prevent back flow.

Abstract: A method is described for separating and processing liquid-borne particles within an aliquot thereof following injection into a field flow fractionator. Said fractionation method may be employed also to capture, for subsequent segregation, specific predefined classes of such particles. The unique fractionation method disclosed contains means to control the applied transverse flow at each designated location along the length of said channel. In one embodiment of the method a separate compartment lies below each distinct location and corresponding membrane supporting permeable frit segment of the fractionator, providing the individual means to control the localized flow through the membrane section thereabove. Employment of a corresponding concentric compartment implementation achieves the same type of compartmentalized cross flow when applied to a hollow fiber fractionation means.