A filter assembly adapted for insertion into an inner chamber of a pressure vessel, wherein the assembly includes: a spiral wound membrane module (2) comprising at least one membrane envelope (4) and feed spacer sheet (6) concentrically wound about a central permeate tube (8) extending along an axis (X) forming an inlet scroll face (30) and outlet scroll face (32) and a cylindrical outer peripheral surface (38), an end cap (33) having a surface (72) covering a portion of the inlet scroll face (30) and at least one opening (76) in the end cap surface (72) near the permeate tube for permitting fluid to flow through the inlet scroll face (30) and into the feed spacer sheet (6) of the module (2), and a brine seal (65) having a radially extending flexible lip (70) defining a maximum outer diameter adapted to engage the inner chamber of the pressure vessel; wherein the brine seal is sealed to the end cap (33).

The object of the present invention is to provide a spiral membrane element that can make a composite semipermeable membrane high in effective membrane area, and that can restrain the composite semipermeable membrane from being lowered in rejection ratio by a deformation of this membrane while ensuring the flow rate of a permeation liquid flowing in a permeation-side flow-channel sufficiently. The spiral membrane element comprises a layered body which comprises a composite semipermeable membrane, a supply-side flow-channel member, and a permeation-side flow-channel member; and the permeation-side flow-channel member comprises a tricot knitted fabric having a plurality of ribs each formed by repeating loops in a linear form in a longitudinal direction, and a plurality of grooves present between the ribs; has a membrane support index of 60 to 135, the membrane support index being calculated in accordance with the specified numerical relationship.

An object of the present invention is to provide a channel material which, when introduced as a liquid separation membrane module, is capable of retaining the salt removal rate of a separation membrane even when a high pressure acts from the supply side through a reverse osmosis separation membrane, and which has a small thickness.

The channel material is a channel material for a liquid separation membrane module which includes a tricot fabric formed by knitting synthetic fibers. The tricot fabric has a convex portion formed by a double loop, and the long side length of an opening formed inside the double loop is 50 to 260 ?m. In addition, in the liquid separation membrane module, at least the reverse osmosis separation membrane and the channel material are wound around a central tube.

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.

The purpose of the present invention is to provide a method for producing a spiral wound separation membrane element that is capable of maintaining the membrane performance of a composite semipermeable membrane before processing into an element and has excellent membrane performance. This method for producing a spiral wound separation membrane element includes: a step for preparing a composite semipermeable membrane having a skin layer on the surface of a porous support; a step for forming on the skin layer a protective layer containing 35 mg/m.sup.2 or more of an anionic polyvinyl alcohol to prepare a protective layer-equipped composite semipermeable membrane; a step for preparing an unwashed spiral wound separation membrane element using the protective layer-equipped composite semipermeable membrane; and a step for passing wash water through the unwashed spiral wound separation membrane element to remove the protective layer on the skin layer.

A filter assembly adapted for insertion into an inner chamber of a pressure vessel, wherein the assembly includes: a spiral wound membrane module (2) comprising at least one membrane envelope (4) and feed spacer sheet (6) concentrically wound about a central permeate tube (8) extending along an axis (X) forming an inlet scroll face (30) and outlet scroll face (32) and a cylindrical outer peripheral surface (38), an end cap (33) having a surface (72) covering a portion of the inlet scroll face (30) and at least one opening (76) in the end cap surface (72) near the permeate tube for permitting fluid to flow through the inlet scroll face (30) and into the feed spacer sheet (6) of the module (2), and a brine seal (65) having a radially extending flexible lip (70) defining a maximum outer diameter adapted to engage the inner chamber of the pressure vessel; wherein the brine seal is sealed to the end cap (33).

In at least one embodiment, a membrane filtration element is provided. The element may include at least one feed spacer including a first set of parallel strands extending in a first direction and including a plurality of first strands having a first thickness and a plurality of second strands having a second thickness that is smaller than the first thickness. A second set of parallel strands may extend in a second direction that is transverse to the first direction. The second set of parallel strands may include a plurality of third strands having a third thickness and a plurality of fourth strands having a fourth thickness that is smaller than the third thickness. In one embodiment, the first and second sets of strands include alternating thick and thin strands, which reduce pressure drop in membrane filtration systems.

The present invention relates to a reverse osmosis filter module including an improved feed spacer, and particularly, to a reverse osmosis filter module including an improved feed spacer which has an asymmetric diameter in an intersection in which a first set of filaments and a second set of filaments intersect, thereby reducing differential pressure by increasing a cross-sectional area of a flow path, and mitigating concentration polarization by developing a swirl flow.

A spiral wound filtration membrane element has a scroll face that includes at least two, concentric, axially displaced regions. At least one of those regions is sealed and at least one is unsealed. Such a membrane element can be produced by a winding process followed by a trimming or cutting step which produces the concentric, axially displaced regions. The seal can be applied before, during or after the trimming or cutting step.

The present invention relates to the design of a face mask that incorporates a waste derived warp knit polyethylene terephthalate (PET) permeate spacer layer for daily usage in current pandemic conditions. The central layer in the face masks is a selective hydrophobic layer that is recycled from waste RO membrane modules and is intended for usage as a non-medicated multi-layered face mask for common man. The mechanical strength and shape holding capability enables the preparation of the face mask in a unique 3D shape that extends from the nose bridge to the chin, leaving an air gap between the mouth and the inner layer of the face mask. Design advantage obtained by the incorporation of the PET layer enables smooth facial movements and hindrance free speaking. The 3D folding feature of the mask is seamless and fits snug on the user's face that which prevents spectacle fogging and chances of infections.