Provided is a porous membrane having a high blocking performance suited for filtration application as well as being excellent in water permeability performance, which is capable of providing stable filtering operation over a long period of time. The porous membrane has a cross-sectional pore size index of 40 or more in a region where a membrane thickness position ranges from 0.1 to 0.2 within the membrane thickness which is normalized by defining one surface position as 0 and the other surface position as 1 and divided into ten regions in the membrane thickness direction, the cross-sectional pore size index being calculated by: Cross-Sectional Pore Size Index=(Cross-Sectional Pore Size in the Range)/(Pore Size of the One Surface).

The invention relates to a method and apparatus for treatment of produced or process water from hydrocarbon production to reduce the volume of the produced or process water while simultaneously reducing the salinity of a highly saline stream, for example, the brine from a seawater desalination plant. The method includes causing a feed stream comprising produced or process water to flow through the lumen of a hollow fiber osmotic membrane 4 which is immersed in an open channel 2 or tank of flowing draw solution 6 which has high salinity. In this way, water from the feed stream is drawn through the osmotic membrane 4 by an osmotic pressure differential caused by the difference in salinity between the feed stream and the draw solution 6.

The present disclosure relates to hollow fiber tangential flow filters, including hollow fiber tangential flow depth filters, for various applications, including bioprocessing and pharmaceutical applications, systems employing such filters, and methods of filtration using the same.

To enhance diffusive mass transfer of solutes, the present hemodialyzer in a cylindrical configuration for hemodialysis comprises a blood compartment having a packed bundle of hollow fibers in a reversibly distensible doughnut configuration on a radial cross-section, and a dialysate compartment having an axial spiral flow converter slidably inserted in a center of the packed bundle of the hollow fibers and an outer circumferential space encircling an outer circumferential layer of the packed bundle of the hollow fibers. The axial spiral flow converter is configured to convert an axial dialysate flow to a centrifugal dialysate flow radially spreading from the center of the packed bundle of the hollow fibers to the outer circumferential space of the hemodialyzer.

One aspect of the present invention is a composite hollow fiber membrane including: a semipermeable membrane layer; and a supporting layer that has a hollow fiber shape and is porous, wherein the semipermeable membrane layer contains a crosslinked polyamide polymer composed of a polyfunctional amine compound and a polyfunctional acid halide compound, the supporting layer has a gradient structure in which pores of the supporting layer gradually increase in size from one of an inner surface and an outer surface to the other, has a cut-off particle size of 0.001 to 0.3 μm, and contains a crosslinked hydrophilic resin on at least a dense surface having smaller pores of the inner surface and the outer surface, and the semipermeable membrane layer is in contact with the dense surface of the supporting layer.

The present invention provides a hollow fiber membrane including a cellulose acetate-based polymer, in which when an inner surface of the hollow fiber membrane is observed under an atomic force microscope, a plurality of groove-like recesses oriented in a lengthwise direction of the hollow fiber membrane are observed, an average length of the recesses is greater than or equal to 200 nm and less than or equal to 500 nm, an average width of the recesses is greater than or equal to 15 nm and less than or equal to 50 nm, and an aspect ratio defined as a ratio of the average length to the average width of each of the recesses is greater than or equal to 6 and less than or equal to 22.

Aspects of the present disclosure relate to filtration systems and methods for production of biologically-produced products, which may include pharmaceutical and/or protein products. Certain biomanufacturing systems described herein comprise a bioreactor (e.g., a perfusion bioreactor, a chemostat) and a filter probe comprising a filter bundle comprising a plurality of hollow fibers (e.g., longitudinally aligned hollow fibers). According to some embodiments, a center-to-center distance between any two hollow fibers within the fiber bundle at one or more points along a length of the fiber bundle is relatively large (e.g., greater than or equal to an average outer diameter of the hollow fibers of the fiber bundle, greater than or equal to 1.1 times a minimum diameter of the two hollow fibers). In some embodiments, the hollow fibers within the fiber bundle are arranged in an array (e.g., a hexagonal, linear, annular, or square array).

To enhance diffusive mass transfer of solutes, the present hemodialyzer in a cylindrical configuration for hemodialysis comprises a blood compartment having a packed bundle of hollow fibers in a reversibly distensible doughnut configuration on a radial cross-section, and a dialysate compartment having an axial spiral flow converter slidably inserted in a center of the packed bundle of the hollow fibers and an outer circumferential space encircling an outer circumferential layer of the packed bundle of the hollow fibers. The axial spiral flow converter is configured to convert an axial dialysate flow to a centrifugal dialysate flow radially spreading from the center of the packed bundle of the hollow fibers to the outer circumferential space of the hemodialyzer.

A porous membrane has a thickness of 150 m or greater. The pore diameters of a first surface are smaller than the pore diameters of a second surface. The average value of the pore diameters of the first surface is 60 nm or less, and the coefficient of variation of the pore diameters is 10% or greater and 50% or less.

An apparatus for removing water vapor from a feed gas is provided that comprises a membrane housing, a membrane that divides a first pressure side and a second pressure side of the membrane housing, a feed gas inlet and outlet on the first pressure side, a sweep gas inlet and outlet on the second pressure side, a sweep gas flow regulator, and a pump. In some embodiments the feed gas can be at ambient pressure and a pressure drop across the membrane can be less than about 1 atm.