A composite reverse osmosis membrane having a semipermeable bilayer polyamide composition comprising a base layer containing a rigid crosslinked aromatic polyamide and a top layer containing a flexible aliphatic polyamide is disclosed, the two layers in combination providing reduced salt passage in reverse osmosis desalination of brackish waters and of seawater.

A spiral wound membrane module is suitable for use with high temperature water that may also have a high pH, for example steam injection produced water. The module uses a membrane with a polyphenylene sulfide (PPS) backing material. The feed spacer of the module may be made from polyphenylene sulfide (PPS) or ethylene chlorotrifluoroethylene (ECTFE). The permeate carrier may be made of a woven nylon (i.e. nylon 6, 6) fabric coated with high temperature epoxy. The core tube and anti-telescoping device may be made of polysulfone. In some examples, the module may be used at a temperature of up to 130° C. Optionally, the module may be used at a pH of 9.5 or more. In a filtration method, the module may be operated at a pressure in the range of 150 to 450 psi. The module may be operated at a generally constant pressure.

A spiral wound membrane module is suitable for use with high temperature water that may also have a high pH, for example steam injection produced water. The module uses a membrane with a polyphenylene sulfide (PPS) backing material. The feed spacer of the module may be made from polyphenylene sulfide (PPS) or ethylene chlorotrifluoroethylene (ECTFE). The permeate carrier may be made of a woven nylon (i.e. nylon 6, 6) fabric coated with high temperature epoxy. The core tube and anti-telescoping device may be made of polysulfone. In some examples, the module may be used at a temperature of up to 130° C. Optionally, the module may be used at a pH of 9.5 or more. In a filtration method, the module may be operated at a pressure in the range of 150 to 450 psi. The module may be operated at a generally constant pressure.

Provided is a membrane distillation system capable of real-time monitoring on membrane scaling, which includes: a raw water storage tank configured to store various kinds of fluid; a membrane distillation water treatment unit configured to receive raw water stored in the raw water storage tank to generate pure water, the membrane distillation water treatment unit having an inlet water chamber into which an inlet water flows from the raw water storage tank, a membrane for separating the inlet water in the inlet water chamber into a steam and a concentrated water, and a treated water chamber for receiving the steam separated by the membrane and concentrating the steam; and a membrane wetting detection unit disposed opposite to the membrane to detect a membrane wetting phenomenon and a membrane wetting location of the membrane by measuring a light passing through the membrane in real time.

Provided is a membrane distillation system capable of real-time monitoring on membrane scaling, which includes: a raw water storage tank configured to store various kinds of fluid; a membrane distillation water treatment unit configured to receive raw water stored in the raw water storage tank to generate pure water, the membrane distillation water treatment unit having an inlet water chamber into which an inlet water flows from the raw water storage tank, a membrane for separating the inlet water in the inlet water chamber into a steam and a concentrated water, and a treated water chamber for receiving the steam separated by the membrane and concentrating the steam; and a membrane wetting detection unit disposed opposite to the membrane to detect a membrane wetting phenomenon and a membrane wetting location of the membrane by measuring a light passing through the membrane in real time.

Disclosed herein is a porous membrane having an immobilized enzyme wherein the enzyme is immobilized within pores which are three-dimensionally connected to each other. The porous membrane having the immobilized enzyme is three-dimensionally crosslinked in a molecular level wherein nanopores of 5 to 100 nm are interconnected, so that the immobilized enzyme may be in contact with a reactant in all directions, and the reaction solution may be easily diffused, thereby proceeding with the catalytic reaction fast and conveniently without deterioration of material transport.

Disclosed herein is a porous membrane having an immobilized enzyme wherein the enzyme is immobilized within pores which are three-dimensionally connected to each other. The porous membrane having the immobilized enzyme is three-dimensionally crosslinked in a molecular level wherein nanopores of 5 to 100 nm are interconnected, so that the immobilized enzyme may be in contact with a reactant in all directions, and the reaction solution may be easily diffused, thereby proceeding with the catalytic reaction fast and conveniently without deterioration of material transport.

A forward osmosis membrane for seawater desalination and a method for preparing the same. The forward osmosis membrane has a composite membrane structure including a nonwoven fabric layer; a hydrophilic polymer layer; and a polyamide layer. The hydrophilic polymer layer formed on the nonwoven fabric layer facilitates an inflow of water from the feed water to the draw solution to enhance flux and realize high water permeability in the direction of osmosis. The polyamide layer not only secures contamination resistance and chemical resistance but also minimizes the back diffusion of salts of the draw solution in the direction of reverse osmosis. Hence, the forward osmosis membrane of the present invention is greatly useful for desalination of high-concentration seawater.

A forward osmosis membrane for seawater desalination and a method for preparing the same. The forward osmosis membrane has a composite membrane structure including a nonwoven fabric layer; a hydrophilic polymer layer; and a polyamide layer. The hydrophilic polymer layer formed on the nonwoven fabric layer facilitates an inflow of water from the feed water to the draw solution to enhance flux and realize high water permeability in the direction of osmosis. The polyamide layer not only secures contamination resistance and chemical resistance but also minimizes the back diffusion of salts of the draw solution in the direction of reverse osmosis. Hence, the forward osmosis membrane of the present invention is greatly useful for desalination of high-concentration seawater.

The objective of the present invention is to provide a porous support that is unlikely to curl (the incidence of MD curling is low). This porous support has a polymer porous layer on one surface of a nonwoven cloth layer, the nonwoven cloth layer having an MD bend stiffness of 1.2 to 2.1 g.Math.cm.sup.2/cm, and an MD bend recovery of 0.3 to 0.6 g.Math.cm/cm. The nonwoven cloth layer is impregnated with a polymer that is the material for forming the polymer porous layer, the impregnation ratio of the polymer impregnated in the nonwoven cloth layer being 25 to 34% by weight of the total weight of the polymer in the polymer porous layer and the polymer impregnated in the nonwoven cloth layer.