Printed spacer membrane elements offer the unique advantage of applying any pattern on the membrane surface to act as the feed spacer material. This is in contrast to conventional feed spacer mesh material that is uniform in thickness and density throughout the mesh. More open feed spaces can be utilized but may also result in higher stress concentration, and where the spacer material comes in contact with the opposing membrane leaf. This patent presents concepts for reducing the damage on membrane leaves by increasing the concentration of the print pattern near the center tube where the stress concentration on the membrane leaves is greatest, orienting the membrane sheets prior to rolling to minimize damage from slippage during rolling, moving the fold away from the first features to minimize leaks at the insertion point.

A filter assembly adapted for insertion into an inner chamber of a pressure vessel, wherein the assembly includes: a spiral wound membrane module including at least one membrane envelope and feed spacer sheet concentrically wound about a central permeate tube extending along an axis (X) forming an inlet scroll face and outlet scroll face and a cylindrical outer peripheral surface, and a brine seal disposed concentrically about a portion of the outer peripheral surface; characterized by the brine seal including: i) a radially extending flexible lip defining a maximum outer diameter adapted to engage the inner chamber of the pressure vessel, ii) an end cap surface covering a portion of the first scroll face, and iii) at least one opening in the end cap surface for permitting fluid to flow through the inlet scroll face and into the feed spacer sheet of the module.

A filter element comprises a membrane layer; and a feed spacer on the membrane layer, wherein the feed spacer comprises a plurality of unit cells arranged in three dimensions, wherein each of the plurality of unit cells comprises a cavity defined by a triply periodic minimal surface, and wherein the cavities of the plurality of unit cells are interconnected to allow a fluid to pass through the cavities of the plurality of unit cells.

A membrane envelope comprising a feed spacer, one or more membrane sheets and an adhesive, to give a glue line laminate having a tensile E-modulus of at least 1600 N/mm.sup.2 and/or an elongation at break of 13% or less.

A spiral-wound forward osmosis membrane element (2) includes: a membrane leaf (23) in which an internal flow path extending from a first opening (26A) to a second opening (26B) is formed; and a central tube (31) around which the membrane leaf (23) is wound and which has a feed hole (31A) communicating with the first opening (26A) and a collection hole (31B) communicating with the second opening (26B). The central tube (31) has an interior partitioned to include an inflow region (3A) communicating with the feed hole (31A) and an outflow region (3B) communicating with the collection hole (31B) so that the inflow region (3A) and the outflow region (3B) each form a flow path extending continuously in an axial direction of the central tube (31) from one end to the other end of the central tube (3). Since a liquid fed into the inflow region (3A) is discharged to the outside without passing through two or more internal flow paths (26), the pressure loss in the spiral-wound forward osmosis membrane element (2) is reduced. Thereby, it is possible to provide a spiral-wound forward osmosis membrane element in which the pressure loss of the flow of a fluid is reduced.

A spiral separation membrane element includes a water collection tube; a separation membrane wound around the water collection tube, having a feed-side surface and a permeate-side surface, and including a band-shaped region on at least one end of the feed-side surface in an axial direction of the water collection tube; and a channel material fused to the band-shaped region.

A spiral wound membrane module adapted for hyperfiltration and including at least one membrane envelope and feed spacer sheet wound about a central permeate tube to form an inlet and outlet scroll face and an outer periphery, wherein the feed spacer sheet includes: i) a feed entrance section extending along the permeate collection tube from the inlet scroll face toward the outlet scroll face, ii) a feed exit section extending along the outer periphery from the outlet scroll face toward the inlet scroll face, and iii) a central feed section located between the feed entrance section and the feed exit section; and wherein the feed entrance section has a median resistance to flow in a direction parallel to the permeate collection tube that is less than 25% of the median resistance to flow of the central feed section in a direction perpendicular to the permeate collection tube.

Provided is a compression bar apparatus for applying pressure to desired areas of a thin film composite (TFC) membrane, such as spiral wound TFC membranes and elements, including membranes and elements used for nanofiltration, reverse osmosis or forward osmosis to purify water, such as tap water, seawater, and brackish water. Application of pressure to a spiral wound element by the apparatus produces a membrane with increased sealant penetration, reduced osmotic blistering, and minimal damage to the active area of the membrane. Also provided are methods of using the apparatus.

There is provided a high-quality spiral-type acidic gas separation module which is obtained by winding a laminate including an acidic gas separation layer that has a facilitated transport film and which has no defects in the facilitated transport film, in which the average value of the fiber diameter of a supply gas channel member is in a range of 100 m to 900 m, and the area ratio of concave portions inscribed in a hemisphere having a diameter greater than or equal to three-quarters of the fiber diameter of the supply gas channel member is 50% or less with respect to a surface of an auxiliary support film of a porous support that is on the side opposite to the facilitated transport film.

The present invention relates to a spiral wound membrane element designs that utilize entrance and exit points in the feed space channel and utilize barriers on the perimeter of the feed space as well as barriers in the feed space area to direct fluid flow in the membrane element.