Abstract: A microporous polymeric membrane is made by preparing a polymer-casting solution, casting a thin film of the casting solution on a support base, allowing partial evaporation of the solvent from the cast film for a predetermined period of time and contacting the partially evaporated film with a leaching liquid to provide the microporous membrane. A membrane with particularly good mechanical strength and hydrophilic properties is formed when the casting solution comprises a vinylidene fluoride polymer and from about 35 to about 85% by weight of a vinyl acetate polymer; and when the acetate polymer is hydrolyzed after the leaching step to convert the acetate groups to hydroxyl groups.

Abstract: A membrane apparatus, which apparatus comprises a housing and a spiral membrane module positioned in the housing to define an annular clearance space between the outside wall of the spiral membrane module and the interior wall surface of the housing, and an open-mesh type or netting material peripherally surrounding the spiral membrane module and positioned in the annular clearance space in a partial sealing relationship, to provide a controlled by-pass of the feed stream through the open-mesh-type material in the annular clearance space, to prevent accumulation of feed material in the annular space.

Abstract: This invention is a method for separating blood from other fluids added to the blood in connection with operative procedures. It is particularly exemplified by bypassing a portion of the blood during surgery through an artificial kidney apparatus or the like in conjunction with the oxygenation, simultaneously, of all blood, including that bypassed through the artificial kidney, wherein the excess fluids other than blood are removed for all practical purposes by completion of the operative procedure.

Abstract: Separation of a suspension of two immiscible fluid components is accomplished in a cylindrical pressure vessel divided into a main chamber and, at one axial end, a secondary chamber. A series of sinusoidal plates in the main chamber provides a tortuous passage for fluid to the secondary chamber. The two components tend to separate during such passage, the less dense component collecting in the upper part of the main chamber and the denser component passing to the secondary chamber. The vessel is provided with an inlet to the main chamber, a first outlet from the main chamber for the less dense component and a second outlet for the denser component exiting from the secondary chamber.

Abstract: A bed of particulate ion-exchange material is confined in the cavity of a container bounded by a wall portion of the container which is movable inward of the cavity. Supply and discharge conduits communicate with respective portions of the cavity for supplying the liquid to be purified, and for discharging from the cavity the liquid purified by contact with the particulate material. A biasing device engages the container outside the cavity and biases the movable wall portion inward of the cavity, whereby the particulate material is kept under compressive stress, and channeling due to shrinkage of the bed is avoided.

Abstract: A dialysis system is disclosed for treatment of a first fluid with dialysis fluid, the dialysis fluid being a mixture of water and dialysis concentrate. The system comprises a dialyzer, a source of water, a source of dialysis concentrate, first and second fluid conducting means communicating with the sources of water and dialysis concentrate, pump means associated with the first and second fluid conducting means, and third fluid conducting means for conducting fluid from the pump means to the dialyzer. The pump means serves to draw water and dialysis concentrate through the first and second fluid conducting means respectively, and to mix the water and dialysis concentrate so that a mixture of water and dialysis concentrate is conducted through the third fluid conducting means.

Abstract: A blood dialyzer system which comprises a membrane dialyzer carried by dialysis solution delivery means and having blood and dialysis solution inlets and outlets. The membrane dialyzer is carried in a position whereby the blood inlet is vertically lower than the blood outlet, and the dialysis solution outlet is vertically lower than the dialysis solution inlet. Bubble trap means are provided in direct communication with the blood outlet and blood flow conduits, with the bubble trap means being preferably attached to and carried by the membrane dialyzer. The dialysis solution delivery means is adapted to permit intermittent reversal of the normal flow of dialysis solution through the membrane dialyzer to remove air bubbles trapped therein. Also, improved designs of integral bubble traps carried by dialyzers are shown.

Abstract: A spin-on filter coalescer unit having a flow reversing assembly. The filter-coalescer unit includes a cylindrical body which contains an annular filter element surrounded by a coalescing element, and a final separation stage is spaced radially outward of the coalescing element. A cover encloses the open end of the body and is provided with a central outlet port and a plurality of circumferentially spaced inlet ports. The flow reversing assembly comprises a pair of baffle members, one of which can be the cover, which are spaced apart to define a chamber that communicates with the outlet. A plurality of tubular connecting members form sealed conduits extending through the baffle member and establish communication between the inlet ports and the central axial passage within the filter element.

Abstract: A filtering apparatus includes a plurality of disc-type filtering elements stacked in parallel with each other. Each disc-type filtering element has one or more annular projections thereon facing an adjacent disc defining a filtering slit. One or more fluid passages define a filtering path therethrough. Fine particles are filtered from a fluid by the slits between the adjacent filtering elements. Adjustment of the slit widths permits trapped particles to be removed by back-washing. A power cylinder permits automatic filtering and back-washing.

Abstract: A mixture of solids, mostly finely divided, and oil, such as usually mixed with mill scale, and water is the feed material for this process. Most of the water is first drawn off. Then the material is fed through a plurality of mixers, and after each mixer the entire composition is passed through a separator, herein described as a dewetting apparatus, which separates the fine solids from the oil and returns the expended solvent upstream toward the feed point. The diminished volume of material then passes through a final dewetting screen where the solids are washed by a small stream of fresh solvent and the fine solids then pass through a dryer. All expended solvent is collected and passed through a fractionating still which separates the recovered oil, for storage, and the solvent vapors pass through a condenser to a regenerated solvent storage tank. All of the expended solvent is saved and used over and over.

Abstract: Reverse osmosis, particularly for water desalination, uses semipermeable membranes which selectively permeate purified water from a feed solution pressurized by a reciprocating feed pump driven by rotating crankshaft. Pump action is assisted by depressurizing concentrate fluid within the pump cylinder, which has an internal displacer separating feed and concentrate fluids. Directional valves controlling concentrate fluid flow to and from pump cylinder are actuated mechanically by crankshaft. A dwell interval is provided in displacer motion to permit completion of directional valve actuation while displacer is stationary and displacer rod is providing compression or decompression action to approximately equalize pressure differences across valve ports prior to valve actuation.

Abstract: A land drainage line having a tube or the like forming a conduit through which water will be drained and a knitted pile fabric filter sleeve around the drainage line.

Abstract: A system for separating solids from a slurry containing liquids and solids including an elongated plate having spaced apart openings therethrough, a pair of superposed endless screens supported for sliding movement on the upper surface of the plate. A pond of the slurry is formed over a portion of the run of the screens. A vacuum chamber is provided on the side of the plate opposite the side supporting the screens to draw liquid from the pond through the screens. A roll nip is provided to engage the screens to apply pressure to material on the screens at the nip. Various screen constructions and operating parameters are also disclosed.

Abstract: A membrane filter assembly is disclosed which employs at least one filter membrane and includes support means to prevent overflexing or overstressing of the filter membrane when high fluid pressures occur. The membrane support means includes a substantially co-extensive support or back-up surface spaced a small distance from the membrane to allow liquid flow therethrough but to prevent stretching or flexing beyond its elastic limit. Preferably the support surface comprises a second filter membrane in parallel flow relationship with the first to provide high flow rates during normal flow conditions but which flex together during high pressures conditions to mutually support one another and to prevent further flexure of either membrane beyond its elastic limit.

Abstract: An apparatus for treating uremic patients by means of ultrafiltration, in which the withdrawn blood is separated by means of a hemofilter into plasma water and residual blood and the plasma water is exchanged in an exchange device. The latter comprises two chambers I and II, separated from one another by a flexible or movable partition, of which chamber I is filled with fluid and can additionally receive the plasma water, and chamber II contains substitution solution. By exerting pressure in the partition, a suction is caused in chamber I and a pressure in chamber II, so that chamber I can take up the plasma water, while the same volume of substitution solution is released from chamber II.

Abstract: A hollow fiber diffusion device comprises a bundle of hollow fibers disposed in a generally rigid, tubular housing having relatively diametrically enlarged manifold members adjacent opposite housing ends. In accordance with this invention, a relatively resilient plastic sleeve member is carried at each end of the housing and sealed to it. Each sleeve member carries an added inner sleeve of less inner diameter than the inner sleeve, being coaxially positioned with the housing to receive, hold, and center the ends of the bundle. Preferably, the sleeve is made of a material which sealingly adheres to the potting compound to facilitate the sealing of the system.

Abstract: A leukocyte filter for blood which includes a housing defining a blood inlet and outlet at respective ends thereof, with the housing enclosing and carrying a tubular, non-woven fiber filter element, with one of the inlet and outlet communicating with the interior of the tubular filter element, and the other of the inlet and outlet communicating with the exterior of the tubular filter element. In the tubular filter element, essentially all of the fibers define diameters of 10 to 100 microns, and have other diameter restrictions described herein, with the fibers being bonded together to define a generally fixed, average interstitial spacing which is less at the inner surface of the tubular filter element than at the outer surface thereof. The air permeability of the filter per square foot is preferably from essentially 15 to 45 SCFM at one half inch of water.

Abstract: A hemodialysis unit has an integral partition disposed across the length and width of the interior of the dialysate chamber separating the dialysate chamber into two subchambers. The first of the two dialysate subchambers has a blood perfusion unit floor and the second dialysate subchamber has a blood perfusion unit ceiling respectively, both subchambers having the opposed exterior length and width margins of the blood perfusion unit sealed to the opposed bonding edges of the dialysate chamber. The cross sectional areas of the two dialysate subchambers so formed are adaptively sized to provide a high velocity flow of dialysate solution over the length of the two subchambers, providing a more rapid sweep of the diffusional boundary layer from the exterior of the two opposed faces of the blood perfusion unit, providing a high rate of removal of waste excreta products from a patient's blood.

Abstract: Apparatus and method for separating and removing oil and particulate solids from a dispersion of oil and particulate solids in water or a water-based liquid. During separation, the dispersion is fed under pressure into the inlet end of a plurality of upright coalescer tubes made of a single-layer of flexible, water-permeable fabric and is prevented from exiting through the outlet end of the tubes. The water passes radially through the fabric walls into a stilling chamber surrounding the coalescer tubes and exits through a clean water outlet while the solid particulates are retained on the inner surface of the fabric. The oil particles coalesce on the inner surface of the tubes, forming a layer of oil which migrates through the fabric's pores due to the pressure differential between the inner and outer tube surfaces and forms an oil layer on the outer surface of the fabric.

Abstract: A hinge assembly for a filter housing cap. The hinge assembly also serves as a hold-down for the cap. With securing devices loosened, the cap may be lifted from its closed position and remain connected to the housing.