Abstract: Hollow fiber membrane cassettes (1000) comprising an exterior casing (400), a filter (20) comprising two or more hollow fiber membranes (21), and an internal manifold (50) comprising first and second cassette headers (51, 52), wherein the cassette is arranged to allow feed flow, retentate flow, and permeate flow, and methods for making and using the cassettes, are disclosed.

Abstract: A carbon nanotube mesh for separating, concentrating, and/or filtering molecules, and a method for fabricating the same. The carbon nanotube mesh includes a plurality of intertwined free-standing carbon nanotubes which are fixedly attached to a substrate. In one embodiment, the microdevice is fabricated by growing the intertwined free-standing carbon nanotubes to extend by free growth from the surface of the substrate into free space.

Abstract: A unique filtration device (10) which removes metal ions from a contaminated aqueous stream through the use of partially hollow wicking fibers (20) impregnated with a selected liquid (18) which can capture the metal ions in the aqueous stream. The wicking fibers (20) are formed into a filter element (12) which extends from a chamber (16) through which the aqueous stream is directed into a chamber (18) wherein the unwanted metal ions are removed from the extracting liquid (18). The wicking fibers (20) include internal longitudinal cavities (22) each with a relatively small longitudinal extending opening (24). The wicking fibers (20) are filled with the selected liquid extraction (18) which remains within the fiber through capillary action by which capillary action the individual wicking fibers (20) rapidly draw the selected liquid,(18) with which they comes into contact, through the internal cavities (22).

Abstract: A separation end cap adapted for connecting adjacent separation elements is provided. The end cap may be located at the distal ends of a separation element and is adapted for connection with a permeate tube located within the separation element. In one embodiment the end cap includes an inner hub for receiving an O-ring to seal against an inner hub of an end cap on an adjacent separation element. The inner hub of the end cap may be spin-welded to the outer surface of the permeate tube. A locking structure on an outer hub of the end cap co-acts with a locking structure on an end cap of an adjacent separation element to releaseably lock the end caps and, therefore, adjacent separation elements. The locking structure preferably provides a predetermined axial force on the O-ring to seal the connection between permeate tubes of adjacent separation elements.

Abstract: A blood purifying apparatus having excellent purification performance (elimination of low molecular proteins, etc.) and being contaminated with little endotoxins flowing from the dialyzate side is described. Attention was paid to the solute permeability coefficient &agr; and water permeability performance Lp of blood purifying apparatus and the relation between &agr; and Lp has been examined. As a result, a blood purifying apparatus having excellent purification performance and substantially being free from invasion of endotoxins was obtained by regulating the value &agr;/Lp to 6×10−7 or above, or regulating &agr; within a range of 8×105 to 1.5×10−3, and the value &agr;×Lp to 2.4×10−2 or less. Also, a blood purifying apparatus having excellent purification performance and substantially being free from invasion of endotoxins was obtained by regulating the invasion ratio which is obtained by the polymer invasion test to 10% or less.

Abstract: Processes and apparatus are disclosed for producing clear reverse osmosis retentates having silica concentrations which are substantially supersaturated in silica from feedwaters having silica concentrations, without substantial formation of alkali-soluble scale having substantial silica content in the associated reverse osmosis apparatus, by adjusting the pH of such feedwaters to an acidic pH range prior to reverse osmosis in accordance with this invention. Also disclosed are related processes and apparatus for periodically removing minor amounts of alkali-soluble scale having substantial silica content from the apparatus.

Abstract: Porous asymmetric hollow polymer fiber membranes having spiraled inner and/or outer surfaces, as well as filters and filter devices comprising one or more of the hollow fiber membranes, the filter and devices preferably being arranged to direct fluid flow from the inner surface of the membranes to the outer surface, and methods of using the filters and filter devices, are disclosed.

Abstract: A hollow fiber microfiltration (MF) membrane is provided. The casting solution used to make this membrane includes a fiber-forming polymer having a degree of polymerization greater than about 1000, a water-soluble polymer, an anhydride with about 2 to 12 carbon atoms, and a solvent. The membrane is formed by mixing and heating these components to form a viscous dope and then extruding the dope through an annular orifice to form a hollow fiber MF membrane. The hollow fiber membrane is then fed through a coagulation bath and two leaching baths. The membrane is especially useful for filtering liquids, such as wine and juice, so as to remove bacteria, gel, and solid particles from the liquids.

Abstract: Cross-flow filters having improved uniformity in transmembrane pressures and consequent much greater flux are provided by the installation of barriers in permeate channels.

Abstract: To pot membranes in a header, a dense, viscous liquid, suspension or, preferably, a thixotropic, water soluble gel, is placed in a header pan in space reserved for a permeate channel. A plurality of hollow fiber membranes are collected together and their open ends are inserted into the gel. A fixing liquid, typically a resin, is placed over the gel. The fixing liquid surrounds each membrane and then solidifies, simultaneously sealing the outer surfaces of the membranes and forming a plug in the opening of the header to complete the permeate channel. After the fixing liquid has solidified, the gel is removed by various means. The space initially occupied by the gel becomes part of the permeate channel after the gel is removed. In one embodiment, membranes are grouped by a cushioning adhesive which later surrounds the membranes where they exit the completed header.

Abstract: An automated fluid filtration system is disclosed, the system providing flexibility and accuracy for the investigative development of liquid separation processes. The system can be used for optimizing the protocol parameters of laboratory scale separation processes towards larger, commercial scale processes.

Abstract: A method for stretching a hollow fibre while making a stretched filtering membrane from a precursor involves wrapping the hollow fibre around a structure and modifying the structure such that at least portions of the hollow fibre are forced to elongated. For example, the hollow fibre may be wrapped around around two or more supports and the distance between adjacent supports increased. This produces first portions of the hollow fibre stretched to a first elongation and porous to a first porosity and second portions of the hollow fibre that are not stretched or are stretched to a second elongation less than the first elongation and that remain non-porous or become porous to a second porosity which is less than the first porosity. The membrane may be made into a module with second portions of the membranes located at points where the membranes exit the potting material or at turns in loops of the fibres, if any. In various embodiments, the fibre is potted into modules before or after it is stretched.

Abstract: The present invention is a liquid transport member with significantly improved liquid handling capability, which has at least one bulk region and a wall region that completely circumscribes said bulk region, and which comprises a membrane port region and an open port region, whereby the bulk region has an average fluid permeability kb which is higher than the average fluid permeability kp of the membrane port region.

Abstract: A system and method for separating water and oil from a mixture of water and oil in a wellbore is disclosed. The system comprises a wellbore in fluid communication with an oil producing formation to receive a mixture of water and oil. The wellbore includes a horizontal portion and a vertical portion which extends to the wellbore surface. A string of tubing is disposed in the wellbore including segments of gravity tubing and segments of membrane tubing which both ideally disposed in the horizontal portion of the wellbore. The gravity tubing allows the mixture of water and oil to at least partially separate into a layer of oil and a layer of water. The membrane tubing includes a membrane which is selectively permeable to one of the water and oil. The water and oil are separated in the membrane tubing. The separated oil is transported to the well surface and the separated water is disposed of in a water disposal zone adjacent the wellbore.

Abstract: A system and method for separating a hydrocarbon fluid stream and a disposal fluid stream and for dispersing the disposal fluid stream into a body of water. The system includes a production string located in a body of water, and a membrane positioned in the production string for separating the hydrocarbon fluid and the disposal fluid by passing the disposal fluid through the membrane. The membrane separation system provides an efficient solution to disperse disposal fluids removed from a hydrocarbon production stream into a body of water in a controllable and ecologically friendly manner.

Abstract: An apparatus is disclosed for the purification of bio-molecules, especially nucleic acids, comprising a column body with inlet and outlet opening and at least one membrane disposed therein, preferably a silica membrane. Bio-molecules such as isolated nucleic acids are recovered with less dilution and requiring less concentration of the recovery solution by employing a membrane that is 1% to 57% less than the internal diameter of the purification column.

Abstract: A new centrifuge filter is designed for use in an arrayable micro-centrifuge. The filter has an upstream end where fluid enters the filter, an opposite or downstream end, and sides where fluid exits by centrifugal force. The filter is a piece of semipermeable material which is capable of letting certain fluids and small molecules pass therethrough and retaining macromolecules and particles. Also disclosed is an optional support for the filter.

Abstract: An apparatus is disclosed for separating a suspension comprising at least two types of particles which are differently sized or shaped and in which the first type of particle may be deformable at a relatively lower force or faster rate than the second type of particle. A housing is provided having a generally cylindrical inner surface in which is mounted a rotor having a generally cylindrical outer surface. The outer surface of the rotor is spaced from the inner surface of the housing to define a suspension processing gap. A filter membrane is provided on the surface of the rotor or the housing that has pores with substantially precisely dimensioned shapes and sizes to correspond substantially to the shape of the first type of particle, thus allowing passage of the first type of particle and blocking passage of the second type of particle. A suspension is directed into the processing gap for either a selected residence time in contact with the filter membrane and/or at a selected force.

Abstract: The invention is related to a method for separating enantiomers in a supported liquid membrane module by contacting the liquid membrane which may contain a carrier and a phase transfer agent with a feed fluid containing a racemic mixture whereby an enantiomer is transported into the liquid membrane and thereafter contacting the liquid membrane with a sweep fluid whereby an enantiomer is transported from the liquid membrane into the sweep fluid. The enantiomer is then recovered from the sweep fluid. The liquid membrane module is constructed in such a way that the feed fluid and the sweep fluid are adjacent to, but on opposite sides of, the liquid membrane and the feed and sweep fluids have a substantially continuous interfacial contact along the length of the liquid membrane.

Abstract: A pneumatic pump manifold disposable system, configured as a cassette, is used for the purpose of red cell and plasma apheresis. The cassette integrates a separation device, manifold system, macro-aggregate filter, and five pumping chambers for the purpose of separating plasma and red cells from the whole blood. The cassette system, with the separation device directly attached without tubing, simplifies the loading of the disposable set into the hardware, and reduces the manufacturing complexity of the set. The system allows for plasma, plasma and red cells, or just red cells to be stored in long term storage containers after a procedure.

Abstract: A new sanitary filter element is described which provides a structure which cannot harbor contaminants and is readily and thoroughly cleaned as needed. The new device utilizes a uniquely configured adhesive component and membrane and tricot channel sheets which are significantly trimmed in size following adhesive curing. Such configuration eliminates structures within the filter where bacterial and other contamination, or materials which support such contaminants, can accumulate. In addition, a novel cage structure provides turbulent fluid flow while having improved strength and furnishes a site for permanent identification indicia. Finally, an improved step in the manufacturing process, in which a temporary separation sheet is positioned between the membrane and the feed spacer, prevents the occurrence of random unwanted contact adhesions between the two before and during the curing of the adhesive bonding membranes and their adjacent tricot channeling sheets.

Abstract: A tangential flow filtration apparatus is provided which includes a liquid feed reservoir and a tangential flow filtration module connected together by manifolds. The manifolds eliminate the need for tubular conduits, thereby effecting a reduction in recirculation volume for the apparatus.

Abstract: An apparatus in which cryoprotectant in cryopreserved samples is removed with the use of turbulence and convective-dispersion around the cells within the primary cryopreservation container. Convective-dispersion is applied via the combined action of gravity and pulsatile transmembrane flow of buffer through the pores of containers fabricated from appropriate membrane material. By using mechanical forces to aid the process of cryoprotectant removal, the benefits of slow cryoprotectant removal are retained while the actual removal time is markedly decreased.

Abstract: A method and apparatus for microfiltration useful in softening water as well as in removing other dissolved constituents where the method comprises passing water that contains a precipitate through a semipermeable tubular membrane. Filtrate is received from the outside of the tubular membrane and the filtrate contains levels of dissolved compounds at concentrations below those that would be predicted by the solubility limits of the compounds. The method may be practiced at elevated pressures without incurring significant fouling of the membrane. It is particularly suited to removing cations such as calcium and magnesium that contribute to water hardness. The water may be treated prior to passing through the membrane by adjusting pH, adding complimentary anions, or adding a flocculant. The apparatus comprises a series of semipermeable tubular membranes housed in a module. The membranes are fluidly connected to an inlet and two outlets.

Abstract: A shear separation system or method uses shear lift forces and permeate drag forces to separate substances having a size less than a predetermined separation size from substances having a size greater than the separation size. The balance of the drag forces and lift forces affects a predetermined separation size in that the balance of forces retards the transmembrane passage of substances larger than the separation size yet allows substances smaller than the separation size to pass through the permeable membrane.

Abstract: The present invention provides a device for concentrating a blood fraction. The device includes an ultrafiltration unit connected to a fluid delivery system for delivering the blood fraction to be concentrated into the ultrafiltration unit. The device also includes a purge fluid delivery system for expelling concentrate from the ultrafiltration unit. In one embodiment, the device accommodates multiple cycles of concentration. A blood fraction concentration method is also provided. The device and method of the present invention are particularly useful for preparing a plasma concentrate suitable for use in a coagulum-based wound sealant.

Abstract: This invention provides an apparatus and method for desalting a low volume solution for use in connection with an electronically addressable microarray. The apparatus comprises a tubular molecular weight cut-off membrane embedded within a ion exchange resin filled chamber. The apparatus provides a very high surface to volume ratio of membrane pore surface to exchange resin capacity for absorbing charged molecules. The design facilitates the speedy removal of charged molecules from test solutions with the resultant desalted solution having a very low ionic strength suitable for use in the electronic transport of nucleic acids, proteins, and cells.

Abstract: A method and apparatus for microfiltration useful in softening water as well as in removing other dissolved constituents where the method comprises passing water that contains a precipitate through a semipermeable tubular membrane. Filtrate is received from the outside of the tubular membrane and the filtrate contains levels of dissolved compounds at concentrations below those that would be predicted by the solubility limits of the compounds. The method may be practiced at elevated pressures and turbulent flow without incurring significant fouling of the membrane. It is particularly suited to removing cations such as calcium and magnesium that contribute to water hardness. The water may be treated prior to passing through the membrane by adjusting pH, adding complimentary anions, or adding a flocculant. The apparatus comprises a series of semipermeable tubular membranes housed in a module. The membranes are fluidly connected to an inlet and two outlets.

Abstract: The invention relates to a filter assembly for producing a paste-like filter cake and a substantially solids free filtrate or permeate. The filter assembly includes a substantially cylindrical member having an exterior foraminous surface, the cylindrical member being mounted on an elongate shaft for rotating the surface about an axis defined by the shaft. The exterior foraminous surface is covered by a microporous filter media. A stationary housing is positioned adjacent a portion of the exterior surface of the cylindrical member. The stationary housing includes a filter feed inlet and a sealing device and is spaced from the exterior surface a distance sufficient to enable cross flow relative to the filter media. Unique filter seal members promote retention of fluid to be filtered in a filtration area defined by the housing and cylindrical member. As the cylindrical member is rotated about the axis, a cake removal or membrane cleaning device removes filter cake from the filter media.

Abstract: A membrane filtration module, comprising a housing, a semi-permeable membrane, which is accommodated in the housing and has a liquid side for the introduction of liquid to be filtered and a concentrate side opposite the liquid side, as well as a permeate chamber, which surrounds the membrane and is in communication with a permeate-discharge line for discharging permeate. According to the invention, the wall of the housing comprises one or more channels which are closed towards the liquid side and the concentrate side and are in communication with the permeate chamber. These channels act as a permeate discharge.

Abstract: The system comprises a number of membrane modules (21), each one containing one or a bundle of several membrane tubules. The membrane modules (21) are connected on behind the other in series (passes) (43 to 48), which lie in horizontal planes. Several series (passes) (43 to 48) lie vertically on top of each other. Vertically extending collection lines (261, 49, 271) are arranged for the supply to, or respectively the removal of the medium to be filtered from the series (passes) (43 to 48). The arrangement offers a particularly simple assembly.

Abstract: The present invention relates generally to an apparatus and method for separating high molecular weight molecules from low molecular weight molecules. More specifically, the invention relates to the use of microdialysis for removal of the salt (low molecular weight molecules) from a nucleotide sample (high molecular weight molecules) for ESI-MS analysis. The dialysis or separation performance of the present invention is improved by (1) increasing dialysis temperature thereby increasing desalting efficiency and improving spectrum quality; (2) adding piperidine and imidazole to the dialysis buffer solution and reducing charge states and further increasing detection sensitivity for DNA; (3) using low concentrations (0-2.5 mM NH4OAc) of dialysis buffer and shifting the DNA negative ions to higher charge states, producing a nearly 10-fold increase in detection sensitivity and a slightly decreased desalting efficiency, (4) conducting a two-stage separation or (5) any combination of (1), (2), (3) and (4).

Abstract: The invention relates to a method for treatment of liquid, that is meant particularly for filtering of pressurized liquid, such as water led from a water distribution system, by way of an apparatus, which has an essentially closed frame (1), in connection with which there has been arranged at least a filtering device (2) for purifying of liquid and a flow device (3), such as feed-flow and/or exhaust flow arrangements (3a, 3b) for leading of liquid. The filtering device (2) is made of thin filtering film (2a), advantageously made of plastic based material, such as PTM (Particle Track Membrane), TeM (Track-etch Membrane) or like, the thickness of which is preferably 7-25 &mgr;m and the size of pores of which is 0.05-10 &mgr;m. The filtering film (2a) belonging to a filtering device (2) are being purified essentially self-powered, such as by way of a purification device (5) exploiting the pressure (p) or the movement (v1) of the liquid to be treated and/or the liquid that has been treated.

Abstract: A method and apparatus for achieving reverse osmosis, microfiltration, nanofiltration and ultrafiltration, produces Dean vortices against a membrane surface which is advantageously in a form of a wound helical membrane tube.