Embodiments disclosed herein are directed to membranes for filtration, methods of manufacturing the same, and membrane modules incorporating the same. In an embodiment, a membrane is disclosed. The membrane includes a porous cellulose layer, a polyamide thin film layer bonded to the porous cellulose layer, and a fabric support layer that supports the porous cellulose layer and the polyamide thin film layer. The porous cellulose layer has a pore size of about 30 nm to about 500 nm at an exposed surface of the porous cellulose layer.

According to the present invention, even when a high recovery ratio operation is performed, the influence of concentration of ingredients to be separated in the feed fluid can be reduced, the concentration polarization can be prevented by increasing the turbulence effect on the membrane surface, and the fluid permeation performance and the separation performance of the separation membrane element can be maintained.

Embodiments disclosed herein are directed to methods and systems for treating wastewater via forward osmosis. By way of example, the methods and systems disclosed herein may be used to filter one or more precipitated salts and/or other particles from wastewater generated by power plants such as flue gas wastewater, oil and gas wastewater, and other industrial processes. For example, the methods and systems disclosed herein may be used to filter one or more precipitated salts from a wastewater feed concentrate formed during the forward osmosis process that is recirculated through at least one membrane module to continue the forward osmosis process. Filtering the one or more precipitated salts from the wastewater feed concentrate helps limit clogging of open channel feed spacer(s) of the at least one membrane module.

A spiral-wound membrane structure includes a central pipe and a film roll. The central pipe comprises a filter body and end covers separately connected to two ends of the filter body. A passage is formed in the center of the filter body, and two ends of the filter body are embedded in the end covers to be bonded on and sealed by the end covers. The film roll includes a guide cloth, a membrane and a mesh. The film roll is wound on the central pipe. The central pipe is directly made of a filter material, can be used as a pre-filter or post-filter, and can be matched with the film roll in the spiral-wound membrane structure to form a highly-integrated two-in-one composite filter. The composite filter can be mounted on a water purifier.

A spiral-wound electrodialysis module includes an inner electrode positioned about a central axis and an outer electrode surrounding the inner electrode. Ion exchange membranes are arranged in a stack, and each membrane extends in a spiral outward from an inner position proximate the inner electrode to an outer position proximate the outer electrode. The spirals expand outward at a greater-than-linear rate as a function of angle along a length of the spiral from the inner positions to the outer positions.

Embodiments of the present invention provide for the deposition of spacing elements for spiral wound elements that prevent nesting of adjacent spacer layers and occlusion of feed space during element rolling.

Embodiments of the invention provide replacements for a continuous layer of feed spacer mesh in spiral-wound reverse osmosis elements and replacing such mesh with discrete regions of feed spacer supporting the inlet and outlet ends of the element and a stiffening bridge feature to bridge between these regions at the tail end of each membrane leaf comprising the element during the element rolling process. The stiffening bridge feature prevents inward deflection of the inner layer of the membrane leaf during rolling, facilitating proper sealing of the adhesive through the permeate carrier to the adjacent membrane film using known membrane rolling techniques.

A spiral wound assembly including a pressure vessel including an inner chamber, feed inlet, concentrate outlet and permeate outlet and a spiral wound membrane module located within the inner chamber of the pressure vessel; wherein the assembly is characterized by including: i) a flow restrictor comprising: a first and second plate in sealing contact with one another; and a fluid channel located between the first and second plate and including a first end in fluid communication with at least one of the concentrate outlet and the permeate outlet, and a second end adapted for discharging fluid from the spiral wound assembly; and ii) a sensor sheet comprising at least one sensor element located between the first and second plates and in contact with the fluid channel, wherein the sensor sheet is adapted for measuring a property of fluid passing through the fluid channel.

Embodiments described herein are directed to methods of manufacturing a multi-leaf membrane module for filtering product fluid flow (e.g., food products or wastewater) and such multi-leaf membrane modules. In an embodiment, a multi-leaf membrane module is disclosed. The multi-leaf membrane module includes a permeate fluid flow tube defining a permeate fluid flow channel for permeate, and a membrane sheet spirally wound about the permeate fluid flow tube. The membrane sheet includes two or more leaves. Each of the two or more leaves includes a feed spacer including at least one opening formed therein that at least partially defines a feed channel for product fluid flow therethrough and a permeate structure defining a permeate fluid flow channel. The permeate structure of each of the two or more leaves includes at least one membrane and at least one porous permeate spacer.

A manufacturing method for a separation membrane element is a manufacturing method for a spiral-wound type separation membrane element including a perforated hollow tube and a laminated body that includes a separation membrane and is wound around the hollow tube. The manufacturing method includes pressing a press member against a portion of the laminated body that is wound around the hollow tube. The pressing presses the press member to satisfy respective relations defined by formulas (1) and (2):

0.1Ps1Pe(1), and

0.1Ps2Pe(2).