Abstract: A fixed-bed bioreactor with porous carrier bodies (14) for microorganisms. The carrier bodies are sheet-like structures with a small thickness in comparison with the carrier body surface. The carrier bodies are kept spaced apart by means of spacing bars (28), defining flow paths (36) between the carrier bodies. In a process for producing porous carrier bodies for microorganisms, plastics particles (70) are introduced into a moulding space (52) and bonded together therein by application of heat. With this process, an endless extrudate (46) of carrier body material may be produced, from which the individual carrier bodies may be cut off. Alternatively, the process may be carried out by means of a series of pairs of mould halves passing through a mould filling station and a heat supply station.

Abstract: To provide an air filter that does not cause holding members to peel even in a high temperature environment, and which can be produced quickly and easily. An air filter (10) includes a filter member (12), holding members (14) disposed at both longitudinal side edges of the filter member (12), and non-woven fabric members (16) for fixing the filter member (12) and the holding members (14). The filter member (12) includes a non-woven fabric of thermoplastic microfibers. The holding members (14) have a bending resistance sufficient to maintain its shape and hold the filter member (12) in its pleated state. The non-woven fabric members (16) have a heat resistance with a melting point not lower than 90.degree. C. and a temporary fixing ability capable of being disposed at the edge portions of the filter member (12) without using a jig.

Abstract: The invention is directed to a method for making filter preparations including a filter sheet for receiving specimens thereon. The method includes cutting a flexible sheet of material to form a filter frame, and slitting the filter frame to form two slits with a central hole therebetween. The two slits define inner edges of parallel framing parts in the filter frames and outer edges of a presser part. One end of the presser part is pulled upward, and the filter sheet is inserted between the presser parts and the parallel framing parts. Then, the presser part is released downward and restored to its original position, so that the filter sheet contacts an undersurface of the presser part and is contained in the slits between the presser part and the parallel framing parts. The filter sheet also adheres to an upper surface of the parallel framing parts and a portion of the filter sheet is exposed through the central hole for receiving mounting specimens thereon.

Abstract: A molded filter element is fabricated by the method comprising the steps of: preparing a plastic composition of a powder-grain adsorbent of 100 weight parts, an emulsion type synthetic resin binder of 5-20 weight parts having a film-making capability at room temperature, an aqueous high-polymer binder of 0.5-5 weight part, and water of the amount sufficient to change the compound of these agents into a composition having its own shape holding property; pressure-filling said plastic composition in a mold composed of plural members to provide a molded filter element; evaporating water until the molded filter element has a shape-holding strength in a state where at least one member of said mold is removed; and heat-treating the molded filter element at a temperature of 110.degree.-160.degree. C.

Abstract: A separation module to be used for separation and filtration of micro-substances. The separation module comprises a bundled configuration of a plurality of hollow thread-type porous membrane elements made of high polymer material. The bundled configuration is sealingly disposed in a casing, in which the thread-type porous membrane elements are bound each other by means of molten thermoplastic resin.

Abstract: Tube units useful for a variety of application are provided. Preferably, individual laminated tubes are joined to each other by intermediate pieces to produce a wide ribbon of parallel tubes. The tubes are porous to certain substances, allowing them to serve as an apparatus to exchange material between two or more fluid streams. The tubes are particularly useful as membrane modules for exchange of material between two fluids. Continuous and discontinuous methods for constructing such tube units are also taught.

Abstract: A process for the manufacture of hermetically sealed filter units and a product made thereby. The process comprises aligning a porous filter element between two housing parts and a thermoplastic skirt that overlaps the edge of at least one housing part to shield the edge of the filter element disposed adjacent to the skirt, pressing the housing parts together and then injection molding a thermoplastic overmold band around the outer portions of the housing parts to form a hermetic seal at the edge of the filter element.

Abstract: A filter material forming a filter layer consisting substantially exclusively of celluloses and cellulose derivatives. In addition to cellulose acetate fibers, the filter layer contains, in the form of additives, microcrystalline cellulose and microfine cellulose, or else microcrystalline cellulose only. The amount of microcrystalline cellulose can be as high as 70% of the weight of the filter layer and that of microfine cellulose up to 50% of the weight of the filter layer. Cellulose acetate fibers can be excluded if in their place, microcrystalline cellulose having particle sizes less than 10 .mu.m. are used. The manufacturing method provides for cellulose acetate fibers to be first mixed in a wet state with microfine cellulose and microcrystalline cellulose, after which differently prepared celluloses are admixed. The mash formed by mixing is formed into a fleece by means of a known felting method, and the fleece is subsequently dried.

Abstract: The fixing apparatus for fixing a fuel filter in the present invention comprises a ring portion for fixing fuel filter body securely by utilizing contraction force of resin. The fixing apparatus is made of resin softened by heat. The resin fixing apparatus has ring portion for accommodating and fixing a fuel filter. The inside shape of the ring portion is formed similar and somewhat smaller than the outer cylindrical shape of the fuel filter body. When the ring portion is heated and the resin and resin become flexible, the fuel filter is allowed to be press fitted into the ring portion.

Abstract: An activated carbon body having flow-through channels and method of making the body. The method involves combining and shaping channel-forming material and optionally fugitive pore-forming material and non-fugitive support material, and a crosslinkable resin into a green body and curing the resin. The temperature at which the channel-forming material begins to distort is greater than the curing temperature of the resin. The resin is carbonized and at the same time the channel-forming material is vaporized out to form a carbon body having flow through channels in the configuration of the fugitive material. The carbon body is then activated. Among other shapes the channels can be straight, curved or crisscrossed.

Abstract: A disposable box filter having a housing comprising mating channel-shaped male and female portions defining a generally box-shaped fluid chamber, with a pair of fluid ports, and a filter element in corrugated sheet form extending across the fluid chamber. The corrugated filter has generally vertically extending pleats or extremities which are mechanically sealed at each end between a pair of vertical axially extending portions of the filter housing.

Abstract: A process for producing a porous fluid permeable body which is heatable by the passage of electric current therethrough. The process involves coating silicon-containing particles with a cokable organic binder to produce coated particles with a particle size fraction of 0.2 to 10 mm, forming the particles into a molding, coking the binder and heating the molding at 1400.degree. to 2000.degree. C. in the presence of nitrogen to form a doped body containing 30% to 100% .beta.-silicon carbide.

Abstract: A coreless filter comprises a pleated, spirally wound loop of material disposed in a housing. The loop includes a layer of filter material, such as a membrane filter, interposed between two support layers.

Abstract: An exhaust gas filter employed to remove harmful components from exhaust gases, more particularly from exhaust gases expelled by combustion engines, includes flow channels or chambers having gas-permeable walls. The walls are formed by a band having compression-moulded material and spacers with the band wound into a spiral. The spacers serve to form flow channels by maintaining a space between the individual windings of the band. The band and, if required, further parts of the proposed filter are then sintered together to form a unit.

Abstract: Method and device for manufacturing a flat textile structure in which two melts of at least two polymer materials are changed to the form of fibers with the aid of a spinning device and in which fibers are then combined and then solidified. The spinning device consists of a spinning rotor and the polymer materials employed have an charge difference of at least ten unit charges. The two materials are first melted separately from one another. Each melt, by means of a distributor device, is then fed to a group of outlet openings of a spinning rotor unmixed. The fibers emerging from the outlet openings are then stretched and combined to form a common flat structure with the flat structure then being charged triboelectrically by an aftertreatment.

Abstract: A membrane support apparatus is provided which includes a top section, a mating base section and a membrane support surface within the mated sections. The apparatus includes a first peripheral seal formed by extension on one of the sections which mates with a groove on the other of the sections, a second seal formed by a smooth surface on either the groove or the extension which mates with a bead on the other of the groove or extension to form a second peripheral seal. The top section and the base section optionally can form a third peripheral seal about the periphery of a membrane on the membrane support surface.

Abstract: An electret filter formed by laminating a plurality of network electret film-split fiber fleeces having a different mesh size. It exhibits a high collecting efficiency with a very small pressure loss and without any appreciable fiber dropping, or any channeling.

Abstract: The humidity exchanger medium is manufactured by forming a laminate of (i) a corrugated sheet and (ii) a flat sheet bonded to points of contact of a ridged surface of the corrugated sheet, the laminate having been impregnated with sodium silicate waterglass and then partially dried, each corrugated and flat sheet constituted of a paper of inorganic fibers; forming a honeycomb matrix from at least one laminate; soaking the honeycomb matrix in an acidic solution containing at least a titanium inorganic salt to convert the sodium silicate waterglass to a titanium-containing silicate hydrogel; and washing and drying the honeycomb matrix to convert the titanium-containing silicate hydrogel to a titanium-containing silicate aerogel.

Abstract: The present invention provides a method of preparing a support for a filtration medium comprising passing a sheet of nonwoven fibrous polymeric material having first and second sides through a calender which comprises a nondeformable roll and a resilient roll, the nondeformable roll being maintained at a temperature below the melting temperature of the material, so as to increase the smoothness of the first side of the material which contacted the resilient roll. A filtration medium support material prepared in accordance with the method of the present invention, as well as a filter comprising a filtration medium and that filtration medium support material, are also provided by the present invention.

Abstract: Improved composite semipermeable membranes including microporous carbonaceous adsorptive material supported by a porous substrate for use in separating multicomponent gas mixtures in which certain components in the mixture adsorb within the pores of the adsorptive material and diffuse by surface flow through the membrane to yield a permeate stream enriched in these components. Methods for making the improved composite membranes are described including one or more oxidation steps which increase the membrane permeability and selectivity.

Abstract: A cylindrical polymer fiber filter cartridge for liquid filtration is formed by applying an acrylic latex binder, diluted with water, to a batt of thermoplastic polymer fibers and winding the batt onto a core to form a hollow fibrous cylinder while applying compression with a compression roll to an outer surface of the fibrous cylinder. After the batt is fully wound onto the core, the cylindrical cartridge is rotated at a speed sufficient to cause the acrylic latex binder to foam in-situ thereby fluidizing the cartridge to allow the polymer fibers in the cartridge to reorient to form a smooth outer surface on the cartridge and to evenly distribute the acrylic binder throughout the cartridge. The binder in the cartridge is then cured to bond the fibers together at their points of intersection and annular grooves are cut in the outer surface of the cartridge to increase the surface area of the filter.

Abstract: This invention relates to a filter for the partial and at least temporary interruption of a vein, comprising a tube made of polytetrafluoroethylene presenting towards its distal end longitudinal notches distributed symmetrically over its periphery and defining flexible bands, and a conduit made of polytetrafluoroethylene inside the tube; the conduit and the tube are joined for example by thermo-welding by their distal ends. A ring made of a radio-opaque material is preferably included between the distal ends during thermo-welding. The flexible bands open out transversely by the conduit sliding in the tube. They have undergone a treatment of thermo-setting, memorizing in the polymeric structure of the tetrafluoroethylene the opened out form and/or a helical form.

Abstract: A module for crossflow filtration, a method of making same, and a filtration device that accommodates at least one such module, which includes at least two multilayer filter units which are stacked on top of one another and are separated from one another by a respective spacer, with the module having at least one channel for unfiltered material and at least one filtrate channel that connects the filter units. The module further includes a sealing material ring for sealingly interconnecting peripheral portions of the filter units, with at least one edge section of the filter units being spaced from the sealing material ring to form the channels for unfiltered material. The layers of each individual filter unit are fused together at least at edge sections that are not embedded in the sealing material ring which, at edge sections of the filter units that are embedded therein, has a width that is sufficient to completely accommodate the filtrate channels.

Abstract: A filter for separating a fluid and particles immixed in the fluid, including a screen formed of a plurality of mutually attached screen panels, each screen panel defined by respective panel edges, and a molded filter frame including a plurality of molded frame members. The panel edges are molded into the molded frame members.

Abstract: An apparatus and method for producing a meltblown continuous and seamless nonwoven tube is described. The apparatus comprises a meltblowing die for extruding two groups of polymer thermoplastic filaments onto a rotating mandrel to form a multilayer layer tube thereon. The tube is withdrawn from the mandrel by a rotating screw. The present apparatus is capable of producing nonwoven tubes having variable fiber diameters and/or composition in the radial direction, making them ideally suited for filtration purposes.

Abstract: A coreless filter comprises a pleated, spirally wound loop of material disposed in a housing. The loop includes a layer of filter material, such as a membrane filter, interposed between two support layers.

Abstract: The disclosure of this invention describes a composite glass fiber structure that includes first and second layers of glass fibers extending in adjacent parallel relation; synthetic resin coating the fibers of each layer and providing a bond holding the layers together in the parallel relation; the fibers of the first layer having smaller diameters than the fibers of the second layer; the first and second layers being gas compressed to have densities of between about 0.25 and 0.45 lbs. per cubic foot.

Abstract: The invention comprises a filter cartridge including a cylindrical filter medium potted into a top cap, and having an internally potted bottom closure molded in place inside the filter medium.

Abstract: A method for manufacturing an air filter consists of building in two stages around a paper filtering element previously prepared, an edge made of flexible foam, first injecting resin into a separate space from the filtering element, and then letting it expand until it anchors to it.An apparatus to carry out such method consists of a die in which the filtering element is inserted, around which a channel is formed where a mobile frame is sinked, whose shape corresponds to the filtering element one, in such a way as to define an injection recess separated from the filtering element, and an expansion recess adjacent to the filtering element, connected by the mobile frame lift, so that the resin can expand and anchor to the filtering element.

Abstract: A method for producing a filter for use in a fuel flow rate regulating mechanism has a first step of providing a sheet of microcellular polymer material having upper and lower surfaces, each of the surfaces being fused to prevent fuel flow through the surfaces. The sheet of microcellular polymer material also has formations of continuous air bubbles between the upper and lower surfaces. The method for producing a filter has a second step of heat pressing in the direction of thickness to rearrange certain of the air bubbles, redefining same as independent, nonconnected air bubbles. The method for producing a filter has a third step of transversely punching from the sheet a filter element of prescribed configurations.

Abstract: A rigidized fiber filter element is produced from a precursor fiber web. The precursor fiber web contains heat-shrinkable fibers or binder fibers or both. The web is exposed to temperatures sufficiently elevated to cause shrinkage of the fibers or melting of the binder. After cooling the web, the filter elements produced are self-supporting, and may have densities up to 500 kg/m.sup.3 to improve filtration while retaining good functional characteristics for operating pressure drop and air permeability. Rigidized fiber filter elements can be constructed of one material, and thus may be suitable for recycling.

Abstract: A fluid mixture separation membrane element (10) includes elongated hollow pressure-resistant nonpermeable transport arteries (12) and a plurality of flexible hollow fibers (14) of semipermeable material having internal flow channels (20). The hollow tubular transport arteries (12) have exteriors (18) and interior flow passages (16). Each hollow fiber (14) has spaced opposite end portions (22, 24) and an elongated tubular portion (26) extending between and interconnecting the opposite end portions (22, 24). The opposite end portions (22, 24) of each hollow fiber (14) are attached by either an adhesive (28) or another suitable mechanism to the tubular transport artery or arteries (12) so as to provide flow communication between the internal flow channels (20) of the hollow fibers (14) and one of the interior flow passages (16) or the exteriors (18) of the hollow transport arteries (12).

Abstract: Objects of the present invention are to provide a membrane filter for liquids which is used in microfiltration or ultrafiltration of liquids such as chemicals, water, and the like and to provide a filtering device using the membrane. The membrane is a membrane filter for liquids which has been rendered hydrophilic, in which the decrease of the pure water permeation flux of the membrane filter after being subjected to wetting treatment with a liquid having a low surface tension, subjected to replacement with pure water, and then exposed to an atmosphere of 25.degree. C. and 60% for 8 hours, to the pure water permeation flux of the membrane filter before the exposure is 20% or less. Such a membrane filter which has been rendered hydrophilic can be obtained by, for example, rendering the surface of a PTFE porous membrane hydrophilic by treating the surface with a low temperature plasma under conditions that a product of high frequency output density and treatment time is from 0.5 to 50 W.multidot.sec/cm.sup.

Abstract: A sandwich of a permeate fabric material within a folded sheet of semipermeable membrane is spirally wound together with a sheet of porous feed pathway material about a mandrel which, upon its removal, provides a central hollow region in the wound element. A single band of adhesive seals the outer end of the envelope, and once wrapping is completed, a thin layer of porous tape holds the winding tight. A porous small diameter tube is inserted into a pocket adjacent the fold in the semipermeable membrane material near the center of the winding and serves as a permeate discharge conduit. Axial ends of the spirally wound subassembly are sequentially potted in resin to complete the basic fabrication of the element. Communication with the feed pathway material is provided by drilling through the resin into the center hollow region.

Abstract: A method of manufacturing a precision micro-filter and a micro-filter manufactured thereby is disclosed. A micro-mold is manufactured using micro-machining technology (such as micro-electrical-discharge machining technology, laser-beam micro-machining, electron beam micro-machining) to make a filter mold with a plurality of rod-like protrusions, of the shape, dimensions, and spacing required for the pores of a finished micro-filter. A molding material is placed into the micro-mold, the molding composition is allowed to solidify to form a micro-filter, the passageways of which conform precisely to the rod-like protrusions of the mold. This micro-filter is then separated from the micro-mold.

Abstract: A film electret and an electret filter that contain a polar high-molecular weight compound and that provides a TSDC curve having a homocharge peak temperature of at least 95.degree. C. and a heterocharge peak temperature of at least 80.degree. C.

Abstract: A filtration medium especially useful in cross-flow type filtration systems comprising a length of porous strong substrate, preferably woven, and a thin porous membrane, such membrane being bonded to the strands of the substrate by islands of resin uniformly spaced apart and disposed generally between the substrate and the membrane. The islands of resin enhance the integrity of the composite during its use in a filtration system. A method and apparatus for the manufacture of the filtration medium is disclosed.

Abstract: This invention relates to an improved thermite coated molten metal filter. According to the invention, a molten metal filter is coated with an aqueous thermite coating slurry containing oleic acid, water-miscible surfactants, water-soluble binders, and water-soluble dispersants.

Abstract: A synthetic hydrophilic membrane, and method for manufacturing thereof, in the form of hollow fibers or flat membranes for dialysis and/or ultrafiltration, containing a mixture of polysulfone and sulfonated polysulfone, the mixture containing 65 to 95 wt.% sulfonated polysulfone, possibly as a salt of sulfonic acid, and 35 to 5 wt.% unsulfonated polysulfone. Preferably, up to 12 wt.% water-soluble polymers, based on the total mixture, are added to the mixture of polysulfone and sulfonated polysulfone before formation of the membrane.

Abstract: A fluid mixture separation membrane element (10) includes elongated hollow pressure-resistant non-permeable transport arteries (12) and a plurality of flexible hollow fibers (14) of semipermeable material having internal flow channels (20). The hollow tubular transport arteries (12) have exteriors (18) and interior flow passages (16). Each hollow fiber (14) has spaced opposite end portions (22, 24) and an elongated tubular portion (26) extending between and interconnecting the opposite end portions (22, 24). The opposite end portions (22, 24) of each hollow fiber (14) are attached by either an adhesive (28) or another suitable mechanism to the tubular transport artery or arteries (12) so as to provide flow communication between the internal flow channels (20) of the hollow fibers (14) and one of the interior flow passages (16) or the exteriors (18) of the hollow transport arteries (12).

Abstract: A membrane for a filter device or a device for gas or liquid separation, the membrane being constituted by a porous structure made of at least one material selected from sintered ceramic, sintered metals, microporous carbon, microporous glass, and polymers, said structure including at least one microporous layer, wherein the entire outside surface and inside surface of the pores of said structure is covered by a thin and continuous film of a polyphosphazene, the thickness of said film lying in the range 0.01% to 10% of the mean diameter of the pores of said microporous layer.

Abstract: An asymmetric polymer membrane is disclosed characterized by being formed by irradiating a monomer and/or an oligomer polymerizable with an energy ray and having a pore diameter distribution in the thickness direction of the membrane, a ratio of a permeability flux of oxygen to nitrogen of 0.9-1.1, and communicating pores.

Abstract: Halogen-substitutable hydrogen atoms are linked to nitrogen atoms of a polymer, with ethylenically-unsaturated monomers. By using inorganic or organic hypohalogenites and/or organic N-halogen derivatives as halogenation means, hydrogen atoms on the nitrogen atoms of the polymer membranes or polymer formed materials are replaced by halogen atoms and part of these are removed by reducing agents in the presence of ethylenically unsaturated monomers, with radical grafting of these on to the nitrogen atoms, after which the remaining halogen atoms are removed by reducing agents in the absence of monomers.

Abstract: Normally hydrophobic fluoropolymer porous membranes having continuous pores are rendered hydrophilic by coating the pore interior with a mixture of at least one fluoroaliphatic surfactant and at least one hydrophilic but substantially water-insoluble polyurethane.

Abstract: An electrostatic air cleaner collector and/or ionizer section has their oppositely charged elements being formed of single, continuous, electrically conductive elements, spirally wound around insulator rods to jointly define a spiral passage through which air is caused to flow. The collector and ionizer may be assembled separately by such a winding process, or they may contain common insulator rods around which the conductive element of both sections may be simultaneously wound. A conductive rod may be inserted to electrically interconnect the high voltage elements of the respective ionizer and collector sections.

Abstract: Hollow fiber membranes can change dimensions upon drying or other processing creating leaks in tubesheets formed on fiber bundles. An adherent layer is formed in contact with an inner surface of each tubesheet and the fiber membranes therein in such a manner as to fill gaps formed between the hollow fiber membranes and each tubesheet during the drying or processing of the hollow fiber membranes and tubesheets. Preferably, the adherent layer is cast from a diglycidyl ether of bisphenol A containing an acrylo-nitrile-modified polyamine curing agent and the hollow fibers are cellulose ester.

Abstract: Porous ceramic articles are made by a method that allows the formed green body to be dried in a dielectric oven without arcing or shorting occurring while maintaining favorable physical properties. The method includes adding water insoluble cellulose and graphite to the ceramic-forming precursors as a burnout material. The method is particularly useful in forming porous cordierite articles that are extruded to form a honeycomb structure conventionally used as a particulate filter for the exhaust fluids of diesel engines. Such articles have a matrix of thin walls forming a multiplicity of open-ended cells extending from one end to another end of the honeycomb. The thin walls have a substantially smaller coefficient of thermal expansion in the direction parallel to the axes of the open-ended cells than in the direction transverse to the thin walls.

Abstract: Semi-permeable microporous polymer bodies, such as porous plates or membranes for separation processes, are provided, these being made of durable high-temperature thermoplastics, e.g., a liquid crystal polymer, by a process comprising melt-mixing the polymer with high loadings of leachable glass and then leaching the glass from the polymer to leave a continuous relict polymer network, the network typically demonstrating pore volumes of 50 percent or more and average pore diameters in the 0.1-10 micron range.

Abstract: The process of making a multilayer membrane composed of a carrier layer, a porous supporting layer and a separating layer includes making a modified polyvinyl alcohol by decomposing a polyvinyl ester or ether until the proportion of the vinyl alcohol monomer units in the modified polyvinyl alcohol corresponds to that in a material consisting of 80 to 95% of the polyvinyl ester or ether and 20 to 5% of a polyvinyl alcohol obtained by completely decomposing the polyvinyl ester or ether; preparing a composite material consisting of the carrier layer and the porous supporting layer, preparing a dilute aqueous solution containing 1 to 10% by weight of the modified polyvinyl alcohol; preferably storing the dilute solution at temperatures from -10.degree. to +10.degree. C., preferably from 0.degree. to 5.degree. C.

Abstract: A process is provided for modifying the properties of a hydrophobic microporous membrane which includes the steps of first providing a hydrophobic microporous membrane, treating it with a surfactant to render the membrane hydrophilic, wetting the membrane with an aqueous solution of a polyol such as polyvinyl alcohol (PVA) and divinyl sulfone (DVS) or a precursor thereof, washing the membrane with water to displace the polyol/DVA from the exterior of the membrane while retaining it in the pores of the membrane, and crosslinking the polyol/DVS into an aqueous gel to yield a hydrophilic microporous membrane having pores filled with an aqueous polyol/DVS gel, the exterior of the membrane being unobstructed by gel. The modified membranes produced according to the process are useful in carrying out chromatographic separations.