Abstract: Filter assemblies are disclosed. In particular, filter assemblies including a filter media and an overlay portion covering the filter media are disclosed. Such filter assemblies may provide both acceptable filtering capacity and cleanable visible front surfaces.

Abstract: A filter assembly includes a housing defining unfiltered and filtered cavities, a coolant inlet, and a coolant outlet. The filter assembly further includes a stop valve movable between a stop valve closed position and a stop valve open position and an anti-drain valve movable between an anti-drain valve closed position and an anti-drain valve open position. The coolant inlet is in fluid communication with the unfiltered cavity when the stop valve body is in the stop valve open position. The coolant outlet is in fluid communication with the filtered cavity when the anti-drain valve body is in the anti-drain valve open position. A filter cartridge includes a bottom endplate having a rib with a rib end face engaging with the stop valve to move the stop valve body from the stop valve closed position to the stop valve open position when the filter cartridge is positioned within the housing.

Abstract: Methods of operating candle filter systems for removing solids from MEG recovered from drilling fluids include passing an MEG rich stream to a candle filter system comprising a plurality of candle filter units in parallel, determining a concentration of TDS in the MEG rich stream, determining whether to operate the candle filter system in a low TDS mode or a high TDS mode based on the concentration of TDS the MEG rich stream, filtering the MEG rich stream in the plurality of candle filter units to produce a filtrate and a filter cake, determining to conduct a cleaning cycle of the candle filter units based on a pressure differential, and conducting a cleaning cycle to remove the filter cake from the outer surfaces of the filter candles. The cleaning cycle is modified to improve removal of solids from the filter candles of the candle filter units.

Abstract: This disclosure relates to filtration screens for use in a backwashable granular media bed filtration system. Drop-in retrofit kits for a backwashable granular media bed filtration system comprising one or more filtrations screens are provided herein. Such screens and kits can comprise a media support screen, a backwash filter screen, or a combination thereof. The kit can further comprise an agitator element comprising an impeller having vanes in which the impeller vane surfaces are coated with an abrasion resistant material. Associated filtration systems and processes are also described herein.

Abstract: The present invention relates to a composite semipermeable membrane including: a support membrane; and a separation functional layer provided on the support membrane, in which the separation functional layer includes a thin membrane, the thin membrane has a fold structure including a plurality of protrusions, an actual length L of the thin membrane per 1 ?m length of the support membrane in a cross-sectional direction perpendicular to a membrane surface is 3.0 ?m or more, and a thickness of the thin membrane in the protrusion is 15 nm or more.

Abstract: Spacers may be attached onto a membrane by a method in which adjacent ones of the spacers are spaced apart from one another with spacings that are accurate to a very fine tolerance. In the method, adjacent ones of the spacers may be attached to one another via lateral members so as to fix the relative spacing between the spacers. The spacers arranged with the fixed spacing may be attached to a transparent substrate via one or more intermediate layers, and thereafter, the lateral members may be severed. Afterwards, a surface of each of the spacers facing away from the transparent substrate may be coated with an adhesive layer. The spacers may be pressed against a membrane so as to attach the spacers to the membrane via the adhesive layer. After being attached to the membrane, the spacers may be detached from the transparent substrate.

Abstract: A blood processing filter, which may be used for white blood cell removal, includes a flexible container having an inlet and an outlet for blood. A filter medium disposed between the inlet and the outlet, and a flow passage-securing member disposed between the filter medium and the outlet. The filter medium includes a filter layer X1 including a filter component unit A1, and a filter layer Y including a filter component unit B. The filter layer X1 is disposed between the filter layer Y and the flow passage-securing member. Ventilation resistances of the filter component unit A1 and unit B are 5.0 Pa·s/m2 or more and less than 9.0 Pa·s/m2 and 9.0 Pa·s/m2 or more, respectively. Ventilation resistances of the filter layer X1 and the filter medium are 4.0 kPa·s/m or more and 20.0 kPa·s/m or less and 55.0 kPa·s/m or more and less than 75.0 kPa·s/m, respectively.

Abstract: Stacked-plate filters may include a plurality of stacked filter plates with small gaps therebetween. The present disclosure provides a stacked-plate filter apparatus comprising a plurality of filter plates stacked along a longitudinal axis with the filter plates substantially parallel. Each filter plate has a respective outer rim, first face and second face. Each of the filter plates defines a respective opening therethrough. The outer rim forms a first peripheral edge at the first face and a second peripheral edge at the second face. The first peripheral edge is radially misaligned from the second peripheral edge to form an offset gap interface for each adjacent pair of the filter plates. For each of the filter plates, the respective outer rim may be tapered from the first face to the second face to provide the radial misalignment.

Abstract: A filter cleaning system including filter cleaning apparatus including a tubular mast rotatingly disposed on a support rod. One or more filter retainers adapted to retain a filter can be disposed on the tubular mast. A filter disposed on the tubular mast can rotate about the support rod. A fluid stream can be directed on the filter to clean the filter rotating about the support rod.

Abstract: A process for manufacturing a porous body, includes preparing a dispersion liquid having a dispersion medium with cellulose-based nanofibers that have an average fiber diameter from 1 to 100 nm and dispersed therein, attaching the dispersion liquid to a porous support having a plurality of pores that connect with one another, removing the dispersion liquid attached to a surface of the porous support excluding an inside of pores of the porous support, and subsequently drying the porous support including the dispersion liquid in the pores of the porous support to remove the dispersion medium.

Abstract: An object of the present invention is to provide a technology in which an amount of pigment carried from a pigment solution can be accurately measured at the time of testing a surface state of a dispensing probe on the basis of the amount of carried pigment. In a test method according to the present invention, a surface state of a dispensing probe is evaluated on the basis of an amount of pigment carried from an acidic pigment solution into a solution including no pigment.

Abstract: A flat membrane support plate includes a connection portion, a honeycomb structural portion and a support portion. The connection portion is configured to connect a diaphragm to the flat membrane support plate in a sealing manner, is arranged at a periphery of the flat membrane support plate, and is provided with at least one water outlet. The honeycomb structural portion is arranged on the flat membrane support plate in an area enclosed by the connection portion, is provided with a first flow channel for communicating with an interior of the entire honeycomb structural portion and communicating the honeycomb structural portion with the water outlet. The support portion is configured for reinforcing the honeycomb structural portion and is arranged between the honeycomb structural portion and the connection portion.

Abstract: The present invention relates to separation methods and systems for converting high concentrations of animal wastes into useful products, wherein the separation of the desired useful products is conducted with a cross-flow filtration system having the ability to the separate desired useful energy and/or products from both viscous and non-viscous medium.

Abstract: A tangential flow filtration module includes plural plate units connected in sequence. Each of the plate units includes a main body, a first combing portion, a second combing portion, a first flange and a second flange. The main body has a first side surface, a second side surface and a through hole. The first side surface is opposite to the second side surface, and the through hole extends from the first side surface to the second side surface. The first combing portion and the second combing portion are disposed on the first side surface and the second side surface respectively. The first flange and the second flange respectively protrude from the first side surface and the second side surface and respectively. The first combing portion of one of the plate units is combined with the second combing portion of another one of the plate units, so that a sieving structure.

Abstract: A filtration cassette including a multilaminate array of sheets including filter sheets alternating with permeate sheet members and retentate sheet members, and a cross-flow filter device comprising a multiplicity of stacked filtration cassettes of such type. The improvements associated with the filtration cassettes described herein include, but are not limited to, at least one of: reinforced inlet(s) providing for longevity and improved cleanability of the cassettes; spacer permeate screens to limit throughput restriction; stainless steel or otherwise stiffened permeate sheets to prevent movement and increase flux; and stainless steel permeate sheets that can be used with ultrasonic transmission to minimize fouling of the filter sheets and extend cleaning cycles. Advantageously, the filtration cassettes are more resistant to higher temperatures than the filtration cassettes of the prior art.

Abstract: A ridge vent for ventilating a roof of a building via a hole along a roof ridge to atmosphere, the ridge vent comprising a first ridge vent panel: a flange portion for resting on the roof, the flange portion having an opening for overlapping with the hole, the flange portion having a first flange portion positioned to one side of the opening and a second flange portion positioned to another side of the opening, such that the first flange portion and the second flange portion are at an acute angle with respect to one another; a frame portion coupled to the flange portion and having sides extending upwardly from the flange portion about the opening, the frame portion for maintaining a cap portion in a spaced apart relationship with the flange portion; the cap portion connected to the frame portion and covering over the opening; a first corrugated filter plate extending between the cap portion and the flange portion and positioned transversely between the opening and the atmosphere, the first corrugated filter p

Abstract: In view of above problems, an object of the invention is to provide a primary containment vessel venting system having a structure capable of continuously discharging vapor in a primary containment vessel out of the system and continuously reducing pressure of the primary containment vessel without discharging radioactive noble gases to the outside of the containment vessel and without using an enclosing vessel or a power source. In order to achieve the above object, an nuclear power plant of the invention includes a primary containment vessel which includes a reactor pressure vessel, a radioactive substance separation apparatus which is disposed inside the primary containment vessel and through which the radioactive noble gases do not permeate but vapor permeates, a vent pipe which is connected to the radioactive substance separation apparatus, and an exhaust tower which is connected to the vent pipe and discharges a gas, from which a radioactive substance is removed, to the outside.

Abstract: Tangential flow filtration systems utilizing flexible bags for permeate collection are provided.

Abstract: A movably-connected and continuously-connected apparatus for uninterrupted high-salinity wastewater purification includes a high-salinity wastewater adsorption treatment system and a movably-connected drainage system embedded in the treatment system. The high-salinity wastewater adsorption treatment system includes four purification zone partition plates, a hollow cylindrical purification zone, a cylindrical water distribution sump located in an axial center of the purification zone, a rotating shaft, a motor, a fixed support and a water tank; the four purification zone partition plates include a first partition plate forming an angle of 135° with a horizontal direction from left to right, a second partition plate forming an angle of 45° with the horizontal direction from left to right, a third partition plate forming an angle of 135° with a vertical direction from bottom to top and a fourth partition plate forming an angle of 135° with the vertical direction from bottom to top.

Abstract: A separation device for separating fluid from a gas stream has a housing replaceably connected to a connector head of a connecting device. The housing has a housing corpus with an axial end covered by a housing cover non-detachably connected to the housing corpus. A filter insert is received in the housing in a flow path of the gas stream from a raw gas inlet to a clean gas outlet of the housing. The filter insert has a main separator element with ring-shaped support body and cylindrical coalescing filter medium with coalescer material removing fluid from the gas stream. A preliminary separator element is arranged concentrically to the main separator element in the housing in the flow path of the gas stream between raw gas inlet and main separator element. The preliminary separator element has a cylindrical coalescing filter medium with coalescer material removing fluid from the gas stream.

Abstract: A process for separating a feed gas comprising a polar gas and a non-polar gas into a permeate gas and a retentate gas, one of which is enriched in the polar gas and the other of which is depleted in the polar gas, the process comprising passing the feed gas through a gas separation module comprising: (i) a feed carrier comprising a membrane envelope and a feed spacer located within the membrane envelope; and (ii) a permeate carrier comprising: (a) a macroporous sheet; and (b) a protective sheet; and wherein: i) the feed gas is fed along the feed spacer of the feed carrier and a part of the feed gas passes through the membrane envelope and into the permeate carrier to give the permeate gas and a part of the feed gas is rejected by the membrane to give the retentate gas; ii) the protective sheet shields at least a part of the membrane envelope from contact with the macroporous sheet; and iii) the protective sheet comprises a non-woven material.

Abstract: A liquid ejecting head including: a first liquid ejecting portion configured to eject a liquid; a second liquid ejecting portion configured to eject a liquid; a first supply flow path configured to supply the liquid to the first liquid ejecting portion and the second liquid ejecting portion; and a temperature detection element for measuring a temperature of the liquid. The first supply flow path includes a common portion to which the liquid is supplied; a first branch portion that communicates with the common portion at a communication position, and that supplies the liquid from the common portion to the first liquid ejecting portion; and a second branch portion that communicates with the common portion at the communication position, and that supplies the liquid from the common portion to the second liquid ejecting portion. The temperature detection element is disposed at a vicinity of the communication position.

Abstract: A forward osmosis membrane having a high chemical resistance includes a backing layer, a selective layer, and a hydrophilic support layer sandwiched between the backing layer and the selective layer. The hydrophilic support layer includes a plurality of nanostructures, each of which includes a carbon nanotube and a hydrophilic film coated around the carbon nanotube, and has an outer layer defined by the hydrophilic films of the nanostructures to prevent the selective layer from penetrating into the hydrophilic support layer.

Abstract: Construction for absorbing a fluid, for example, a liquid or gaseous, organic chemical, has an extended web, fabric, yarn or foam member and associated with the extended web, fabric, yarn or foam member is a water-insoluble polymer. The water-insoluble polymer can absorb the fluid organic chemical, and the construction provides for contact of the water-insoluble polymer with the fluid organic chemical when deployed in an environment where the fluid organic chemical may be present for absorption. The construction may be employed in aquatic, aqueous, or dry environments, as a blotter, a wipe or sponge, a filter, in a cartridge, and so forth.

Abstract: A multilayered polymer composite film includes a first polymer material forming a polymer matrix and a second polymer material coextruded with the first polymer material. The second polymer material forms a plurality of fibers embedded within the polymer matrix. The fibers have a rectangular cross-section.

Abstract: The present invention relates to a melt-joined filter element with improved testability after dry steaming or alternatively after sterilization by irradiation, to a method for producing the filter element according to the invention, and to the use of the filter element for filtering solutions.

Abstract: A ceramic foam filter and a manufacturing method thereof. The ceramic foam filter comprises the following materials provided in respective weight percentages: 20-50% of a silicon carbide, 20-55% of a zirconium oxide, and 10-36% of a silicon oxide, wherein all figures are based on the total weight of the ceramic foam filter. The method for manufacturing the ceramic foam filter comprises the following steps: (a) providing a slurry comprising a silicon carbide, a zirconium oxide or zirconium oxide precursor, a silicon oxide or silicon oxide precursor, a binder, an optional additive, and a fluid carrier medium; (b) applying the slurry to perform surface ornamentation of a perforated organic foam; (c) drying the perforated organic foam surface ornamented with the slurry to obtain a green body; and (d) sintering the green body in oxygen-containing air to obtain the ceramic foam filter.

Abstract: The present disclosure provides for devices, systems and methods for fractionation and concentration of particles from a fluid sample. This includes a cartridge containing staged filters having porous surface in series of decreasing pore size for capture of particles from a fluid sample; and a permeate pressure source in fluid communication with the cartridge; wherein the particles are eluted from the porous surfaces and dispensed in a reduced fluid volume.

Abstract: A cylindrical wall for filtering solid particles in a fluid is disclosed herein, through which a fluid is likely to circulate. This wall includes at least one perforated plate having a finite radius of curvature, and at least one grating element superposed on this perforated plate. The grating element includes a plurality of rigid wires extending in a longitudinal direction and positioned adjacent to one another in order to filter the solid particles, characterized in that the grating element is arranged for the wires to be secured to one another only by means of links between adjacent wires, each link between two adjacent wires occupying only a portion of the length of the wires, and having a thickness less than or equal to the thickness of these wires in proximity to this link.

Abstract: A gas separation membrane, characterized by having a porous support and a polyamine layer formed on the porous support, the number-average molecular weight of the polyamine constituting a part of the polyamine being 100,000-500,000.

Abstract: A rigid structure propellant management device (PMD) liquid storage tank includes an outer shell and internal structures inside the outer shell that include a plurality of vertical columns each made up of a stack of individual storage cells. Each of the storage cells has solid vertical sidewalls and top and bottom capillary windows that allow vertical liquid transfer between adjacent cells in a vertical column. The top and bottom capillary windows in each of the storage cells have permeabilities that result in a selected direction of liquid flow in each column. A piping and valve system may be connected to the top capillary window of a top storage cell and to the bottom capillary window of a bottom storage cell of each vertical column, configured to allow controlled liquid transfer between adjacent vertical columns so that locations of empty cells in the tank as liquid is drawn from the tank achieves a selected column by column drainage sequence and controls a center of mass of the tank.

Abstract: The present application provides a device for treating a black and odorous water body comprising a pre-treatment unit, a biomimetic intestine tubular purification system which imitates a digestion of small intestine, a microbial fuel cell which imitates a digestion of large intestine, and an inclined tube sedimentation tank which imitates human excretion.

Abstract: The present application provides a method for treating a black and odorous water body comprising the following steps: pre-treating the black and odorous water body; passing the pre-treated water body through a biomimetic intestine tubular purification system which imitates a digestion of small intestine; passing the tubular purification system-treated water body into a microbial fuel cell which imitates a digestion of large intestine to treat the water body; and pumping the microbial fuel cell-treated water body into an upward flow inclined tube sedimentation tank to treat the water body.

Abstract: The present invention relates to a proton conductive nanocomposite membrane and a method for manufacturing same, the proton conductive nanocomposite membrane having polyhedral oligomeric silsesquioxane (POSS) having a proton donor and POSS having a proton acceptor introduced into an aromatic hydrocarbon polymer membrane having a sulfonyl group. The nano-composite membrane of the present invention has both the POSS having a proton donor and the POSS having a proton acceptor added thereto, and thus protons (cations) that are generated are easily hopped in an ion channel by means of hydrogen bonding, and thus ionic conductivity is increased. In addition, the POSS used in the present invention has a very small size, and thus hardly obstructs proton migration in the ion channel in the polymer membrane, and thus excellent proton conductivity may be enabled.

Abstract: The present invention relates to a proton conductive nanocomposite membrane comprising a fluorinated proton conductive polymer substance introduced with polyhedral oligomeric silsesquioxane (POSS) having a proton donor and polyhedral oligomeric silsesquioxane (POSS) having a proton acceptor, and a method for preparing the same, in which the addition of the very small size POSS having proton donors and POSS having proton acceptors to the nanocomposite membrane increases ion conductivity due to easy hopping of generated protons (cations) within ion channels, thereby realizing excellent proton conductivity while the nanocomposite membrane shows excellent mechanical strength even though the degree of sulfonation of the membrane is increased.

Abstract: Filter media are described. The filter media may include multiple layers. In some embodiments, the filter media include a nanofiber layer adhered to another layer. In some embodiments, the layer to which the nanofiber layer is adhered is formed of multiple fiber types (e.g., fibers that give rise to structures having different air permeabilities and/or pressure drops). In some embodiments, the nanofiber layer is adhered to a single-phase or a multi-phase layer. In some embodiments, the nanofiber layer is manufactured from a meltblown process. The filter media may be designed to have advantageous properties including, in some cases, a high dust particle capture efficiency and/or a high dust holding capacity.

Abstract: A liquid discharge head includes nozzles, pressure chambers, pressure generators, a common liquid chamber, a partition, and a liquid feeder. The common liquid chamber includes two chamber portions adjacent to each other on a plane parallel to a nozzle array direction. The two chamber portions include a first chamber portion to receive liquid from a supply unit and a second chamber portion to supply liquid to the pressure chambers. The partition includes openings and partitions the first portion from the second portion. The first portion includes at least one liquid inlet at a first end and at least one liquid outlet at a second end opposite the first end in the nozzle array direction. The second portion has a cross-sectional area smaller than a cross-sectional area of the first portion in a cross section of the two chamber portions perpendicular to the nozzle array direction.

Abstract: A diffuser membrane and a method for manufacturing the same are provided. In the method for manufacturing, a first material is heated and extruded to form a base layer and a second material is heated and extruded to form a coating layer. The base layer and coating layer may be extruded substantially simultaneously in a coextrusion process. Accordingly, the coating may be applied to the base layer in a manner that optimizes the bonding between the two layers and provides the ability to control the thickness of the coating layer. Alternatively, the base layer is formed initially and the coating layer is subsequently formed thereover. The first and second materials have differing properties. The first material may comprise polyurethane and the second material may comprise polyurethane and PTFE.

Abstract: A method of recovering one or more insoluble oils from a liquid source using one or more membrane or membrane contactors, comprising the steps of: pumping the liquid source comprising the one or more oils to the membranes or membrane contactors, contacting the liquid source with a first surface of the membrane or membrane contactors, coalescing the one or more oils within the liquid source onto the first surface of the membrane contactors, pumping one or more recovery fluids through the membrane or membrane contactors in contact with the second surface of the membrane or membrane contactors, and removing a first stream of oil coalesced from the second surface of the membranes or membrane contactors.

Abstract: A disk filter (21) has grooves (211) having a curved shape whose curvature gradually increases from the outer peripheral side of the filter disks (21) to the inner peripheral side thereof. The width (Wout) is greater than the width (Win). The width (Wout) is the width of an opening (211a) of each of the grooves (211), the width (Win) is the width of the opening (211a) of each of the filter disks (21). The disk filter includes, in a flow passage for liquid thereof, a stacked body composed of the filter disks (21). The pressure loss of the disk filter (21) is low and the opening ratio thereof is high. The disk filter (21) can appropriately and efficiently filtrate even a low-pressure liquid.

Abstract: An assembly for the rapid removal of trace levels of ionic species from fast-moving flows of water employs a compressed stack of layers of batting containing ion-absorbing granules, and a confining cage for holding the stack in a rectangular configuration.

Abstract: A fluid pressure reduction device includes a radial and axial fluid flow path in stacked disks. The stacked disks form a fluid flow path including at least two pressure reduction stages, a first pressure reduction stage being oriented so that the fluid flowpath is directed radially outward and a second pressure reduction stage being oriented so that the fluid flowpath is directed radially inward.

Abstract: A filter well suited for paint arrestor usage having a monolithic high loft manmade fiber body with a convoluted flow contact surface. The filter is preferably formed by a convoluter as in one with a roller set and blade cutter to form mirror image fiber filter sheets from a received fiber batt. Provided is a well mixed proper fiber blend, such as one having a set of fibers made of a majority of course fibers joined by way of thermal bonding fibers which facilitate, during convoluting, formation of a crisp cut and high integrity three dimensional surface, as in one of rows of peaks separated by valleys. The projection/recess arrangement over the flow contact surface as well as the thickness and relative projection-to-base dimensions are arranged to provide a high paint holding capacity without too fast a load up of, for example, paint particles and while avoiding too great of a pressure drop within that load up time.

Abstract: A light weight oriented net or netting assembly is provided for oil capture and containment. The netting assembly is made by biaxially stretching or orienting starting materials to form a pattern of oriented strands and integral junctions that, while being light in weight, is also strong enough to be used to capture and remove oil from contaminated water without an outer stabilizing jacket. The assembly is preferably made from oriented polypropylene netting that is folded, gathered, bunched and/or otherwise layered upon itself on the order of 16-64 times and then crimped in one or more locations to secure the netting layers in a bow tie or tubular configuration that forms net cavities and an open cell structure to capture and contain oil that has been dispersed in water. Oil in the netting assembly can then be removed, such as by pressing or other removal process, after which the netting assembly may be reused.

Abstract: A fluid treatment arrangement may include a fluid treatment unit having a multilayer structure. The multilayer structure may include at least one feed layer, at least one permeate layer, and at least one layer of a permeable fluid treatment medium between the feed layer and the permeate layer. The fluid treatment unit may further include a thermoset which holds the layers together and forms at least a portion of a first end surface of the fluid treatment unit. The fluid treatment arrangement may also include a thermoplastic sheet which overlies the first end surface of the fluid treatment unit. The thermoset directly bonds to the thermoplastic sheet.

Abstract: A two-layered osmosis membrane contains a support layer and a rejection layer. The support layer, in which a mesh is embedded, is made of a phase separation polymer and has a thickness of 50 to 200 ?m. The rejection layer, which adheres to the support layer, is made of a thin film composite polymer and has a thickness of 0.05 to 3 ?m. The mesh, which is embedded in the support layer, has an open area of 30 to 70%, a mesh size of 60-300 mesh, and a thickness of 45-150 ?m. Also disclosed is a method of making the above described membrane.

Abstract: A separation membrane structure 1 has partition walls 3 including a honeycomb shaped porous ceramic body 9 provided with a large number of pores, and cells 4 to become through channels of a fluid are formed by the partition walls 3. The cells 4 include separation cells 4a and slit cells 4b. In the separation cells 4a, the intermediate layer is disposed on the surface of a substrate 30, and a separation layer is further formed. The intermediate layer has a structure where aggregate particles are bonded to one another by an inorganic bonding material having a thermal expansion coefficient equal to or higher than that of the aggregate particles.

Abstract: An apparatus and method for skimming oil and other liquid hydrocarbons and contaminates floating at the surface of a body of water or other suspending liquid. A rigid skimming surface such as a drum or disc is floatably supported on pontoons. The skimming surface is rotatable about an axis substantially parallel to the water surface. The skimming surface is covered with removably attached sorbent material which improves the efficiency of the oil recovery operation and which, when worn or soggy, can be removed and discarded without discarding the skimming surface.

Abstract: A leukocyte-removing filter, characterized in that it comprises a filter material having a vertical permeation coefficient (kx) of 0.5×10?12 to 2.0×10?12 m2 and a ratio (ky/kx) of a horizontal permeation coefficient (ky) to kx of 0.5 to 1.5; and a method for removing leukocytes using said filter. The above leukocyte-removing filter has a higher leukocyte-removing performance per unit volume and also does not bring clogging nor increase of pressure drop.

Abstract: A composite semipermeable membrane includes: a supporting membrane having a substrate and a porous supporting layer; and a separation functional layer provided on the supporting membrane, in which, when any 10 cross sections of the composite semipermeable membrane, having a length of 2.0 ?m in a membrane surface direction, are observed using an electron microscope, an average number density of projections on the separation functional layer, which have a height equivalent to or higher than ? of a 10-point average surface roughness of the separation functional layer, is 10.0 pieces/?m or more, in each cross section, and an average height of the projections is 100 nm or more.