Provided is a feed spacer having a three-layer structure, in which a set forming the feed spacer is formed in a three-layer structure, so that the set, which is in contact with a reverse osmosis membrane, convects raw water to a center of the structure of the feed spacer and a laminar flow velocity gradient is generated at the center to decrease a polarization phenomenon of a reverse osmosis filter module and minimize pressure loss, and a reverse osmosis membrane filter module including the feed spacer.

Provided is a feed spacer having a three-layer structure, in which a set forming the feed spacer is formed in a three-layer structure, so that the set, which is in contact with a reverse osmosis membrane, convects raw water to a center of the structure of the feed spacer and a laminar flow velocity gradient is generated at the center to decrease a polarization phenomenon of a reverse osmosis filter module and minimize pressure loss, and a reverse osmosis membrane filter module including the feed spacer.

A two-stage filter enclosed within a single vessel is provided. The two-stage filter is provided in the form of the vessel having a first filtration stage configured to capture particles of a first size, and a second filtration stage downstream of the first filtration stage and in fluid communication with the first filtration stage configured to capture particles of a second size, wherein the first size is larger than the second size. The first filtration stage may comprise a porous media. The second filtration stage may comprise one or more membrane filters.

A two-stage filter enclosed within a single vessel is provided. The two-stage filter is provided in the form of the vessel having a first filtration stage configured to capture particles of a first size, and a second filtration stage downstream of the first filtration stage and in fluid communication with the first filtration stage configured to capture particles of a second size, wherein the first size is larger than the second size. The first filtration stage may comprise a porous media. The second filtration stage may comprise one or more membrane filters.

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 feed spacer, in which angles of strands are differently formed in one feed spacer according to a flow direction of raw water, so that a differential pressure decrease region and a recovery increase region are separated to perform multiple functions, and a reverse osmosis filter module including the feed spacer.

Photocurable compositions that have a color change during curing and methods of preparation and use of such compositions. More particularly, the present invention relates to photocurable compositions that that have a color change during curing and are useful for forming topographical features, e.g., spacer features, and/or fold protection coatings on a portion of a membrane surfaces, and particularly on membranes used in osmosis and reverse-osmosis applications, such as membrane filters.

Photocurable compositions that have a color change during curing and methods of preparation and use of such compositions. More particularly, the present invention relates to photocurable compositions that that have a color change during curing and are useful for forming topographical features, e.g., spacer features, and/or fold protection coatings on a portion of a membrane surfaces, and particularly on membranes used in osmosis and reverse-osmosis applications, such as membrane filters.

An assembly for treating a liquid is provided. The assembly includes a pressure vessel having first and second ends provided with respective first and second endcaps, a membrane element positioned within the pressure vessel, an adapter coupling the first endcap with a first end of the membrane element, a first set of shims positioned between the first endcap and the first adapter, a first thrust collar positioned between the first endcap and the first end of the membrane element, a second thrust collar positioned between the second endcap and a second end of the membrane element, and a second set of shims positioned between the first thrust collar and the first end of the membrane element. An overall thickness of the second set of shims is the same as an overall thickness of the first set of shims.