A spiral-wound acid gas separation membrane element (1) includes a wound body including a separation membrane (2), a feed-side channel component (3), and a permeate-side channel component (4) wound in a laminated state around a core tube (5). The core tube (5) has a group of holes for allowing communication between a permeate-side spatial portion defined by the permeate-side channel component (4) and a spatial portion inside the core tube (5), the group of holes being present on an end side of the core tube (5).

A method for conditioning natural gas into fuel gas, where the method includes the step of: delivering a natural gas stream including both CO.sub.2 and C2+ hydrocarbons to a membrane separation assembly; and separating the natural gas stream into the following streams: (i) a first permeate stream, (ii) a second permeate stream, and (iii) a residual stream. The first permeate stream includes CO.sub.2 removed from the natural gas stream. The second permeate stream includes methane at a greater concentration than a concentration of methane in the natural gas stream. The residual stream contains C2+ hydrocarbons at a greater concentration than a concentration of C2+ hydrocarbons in the natural gas stream.

Disclosed are an integrated composite filter cartridge (200) and a water purifying system (300) having same. The integrated composite filter cartridge (200) comprises: an outer shell (20), wherein a chamber (21) is defined in the outer shell (20), and the outer shell (20) is provided with a raw water inlet (22), a pre-treated water outlet (23), a pre-treated water inlet (24), a purified water outlet (25) and a waste water outlet (26) which are in communication with the chamber (21); a pre-treatment filter cartridge (100); a central pipe (30); a filter membrane (40); and a control member, which is connected to the pre-treated water outlet (23) and the pre-treated water inlet (24). When the integrated composite filter cartridge (200) is used for the first time, the control member switches on the raw water inlet (22) and the pre-treated water outlet (23) and switches off the pre-treated water inlet (24).

An electrodialysis cell includes a housing defining an internal chamber, a core positioned within the internal chamber, a first electrode positioned in the internal chamber adjacent the housing, a second electrode coupled to the core and spaced from the first electrode, and a membrane assembly positioned between the first and second electrodes in a spiral wound configuration. The housing includes an inlet end for receiving a feed fluid and an outlet end in fluid communication with the inlet end. The membrane assembly includes a plurality of ion exchange membranes spaced from each other to define a plurality of fluid channels between the inlet and outlet ends.

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.

Provided is an interfacial polymerization process for preparation of a thin film composite membrane, which can be used for nanofiltration, forward osmosis, or reverse osmosis, particularly for use with brackish water or seawater. The process includes contacting a porous support membrane with an aqueous phase containing a polyamine to form a coated support membrane, and applying an organic phase containing a polyfunctional acyl halide to the coated support membrane to interfacially polymerize the polyamine and the polyfunctional acyl halide to form a discrimination layer of a thin film composite membrane, where during formation of the membrane, the polyfunctional acyl halide is purified in situ by removal of hydrolyzed acyl halide through addition of a salt rejection-enhancing additive that includes a biguanide compound, dicarbonate compound, pentathiodicarbonate compound, or salt thereof. Also provided are the membranes prepared by the methods and reverse osmosis modules containing the membranes.

The present invention relates to a crossflow membrane module configured to separate a feed fluid into a permeate fluid and a residue fluid across one or more membrane sheet(s). The crossflow module comprises a second end offset from a first end along the first direction where an inlet is provided at the first end and an outlet is provided at the second end. The one or more membrane sheet(s) each have a first portion and a second portion. A conduit is adjacent to the first side of each membrane sheet and is configured to receive and output the permeate fluid separated from the feed fluid. The second portion of the membrane sheet has a greater permeance for a major component than the first portion such that the second part of the permeate fluid, which is generated by separation across the second portion of the membrane sheet, has a higher concentration of the major component than the first part of the permeate fluid, which is generated by separation across the first portion. The second portion is spaced apart from the first side of the membrane sheet along the second direction thereby causing the second part of the permeate gas to flow towards the first side of the membrane sheet such that the second part of the permeate gas mixes with the first part of the permeate gas thereby reducing the concentration of the minor component in the first part of the permeate gas.

Provided herein are methods and systems for water purification from oxyanions, nitrate in particular, by Donnan dialysis unit coupled with a bioreactor, to allow the uninterrupted or minimally interrupted operation of the technological assembly.

The invention provides a semipermeable composite membrane that reduces an environmental load, and a method of producing the semipermeable composite membrane. A semipermeable composite membrane 100 includes, on a porous support 102, a semipermeable membrane 104 containing a crosslinked polyamide 120 and a cellulose nanofiber 110. A method of producing the semipermeable composite membrane includes obtaining a mixed solution containing the cellulose nanofiber 110, water, and an amine component, and obtaining the semipermeable composite membrane 100 by making the mixed solution be in contact with the porous support 102, thereafter, causing a cross-linking reaction of the amine component in the mixed solution, with the amine component adhering to the porous support 102.

A fluid separation element including: a wound body in which a separation membrane is wound around a central pipe; and an anti-telescoping plate, in which the anti-telescoping plate has an opening part that penetrates through the anti-telescoping plate, the central pipe is inserted into the opening part, a depression is formed in at least one of a surface, in the opening part, of the anti-telescoping plate and an outer surface of a portion, inserted into the opening part, of the central pipe, and a gap between the opening part and the central pipe and the depression are filled with a resin.