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).

A method of removing chemical contaminants from a composition comprising an active, a solvent, and a contaminant can include providing an initial feed supply, wherein the initial feed supply comprises the active, the solvent, and the contaminant, wherein the contaminant can include 1,4 dioxane, dimethyl dioxane, or a combination thereof; including filtering the initial feed stock through a nanofilter.

According to various aspects and embodiments, a system and method for polishing ultrapure water (UPW) is disclosed. The water polishing system includes a source of ultrapure water (UPW), an ultrafiltration (UF) module having an inlet and a permeate outlet, a recirculation conduit communicating the permeate outlet with the inlet and forming a recirculation loop, a recirculation pump disposed along the recirculation conduit upstream from the inlet of the UF module and fluidly coupled to the source of UPW, a supply conduit fluidly coupled to the recirculating conduit and a demand source, the supply conduit positioned downstream from the permeate outlet, and a pressure control valve disposed along the recirculation conduit downstream from the supply conduit and configured to maintain pressure of permeate at a predetermined value.

In a membrane filtration system and process, retentate exiting a filtration element is maintained inside a loop and redirected back to the inlet of a pump. The pump may produce a generally constant velocity in the loop. Water is concentrated inside the loop until discharged in batches. Feed water enters the loop automatically. The flux through the filtration element is maintained by a controlled valve or pump in communication with a permeate outlet. A filtration element has one or more rigid inserts in a housing. The inserts are covered with membranes. The element is configured to provide open feed channels beside the inserts. The membranes and inserts are potted at an edge, which may be their only attachment to the housing. Permeate flows between the membrane and the insert to the potted edge. The filtration element may be used in the system and process described herein or in others.

Disclosed herein are systems and methods in which ion-selective separation and multi-stage osmotic separation is used to produce multivalent-ion-rich process streams. According to certain embodiments, multiple separations may be used to process an aqueous feed stream containing solubilized monovalent ions and solubilized multivalent ions to produce a stream enriched in the multivalent ions. The separations may be arranged, according to certain embodiments, to enhance the overall separation process such that the product stream containsrelative to the initial aqueous feed streama high amount of multivalent ions, a high amount of water from the aqueous feed stream, and/or a high ratio of multivalent ions to monovalent ions.

Provided is a reciprocating submerged membrane filtration apparatus including: a membrane tank comprising a submerged membrane and configured to intake influent wastewater to be treated, the influent wastewater being filtered through the submerged membrane to produce treated water; and a reciprocation apparatus configured to move the membrane to create an inertia force which shakes foulants off from the submerged membrane under oxygen-deficient conditions, wherein the submerged membrane comprises a microfiltration (MF) membrane or an ultrafiltration (UF) membrane.

Systems for water desalination are disclosed. The systems include a source of non-potable water, a low pressure nanofiltration device, a first electrodialysis unit, a second electrodialysis unit, and recycle conduits. Methods of water desalination including directing non-potable water to a low pressure nanofiltration device, a first electrodialysis unit, and a second electrodialysis unit are also disclosed. Methods of facilitating water desalination by providing a water desalination system are also disclosed.

A multi-stage polymeric membrane module system separates a gas, such as air, into components of high purity. In at least two of the stages, a portion of the retentate gas is directed into the low-pressure side of the module, to act as a sweep gas. The use of the sweep gas reduces the partial pressure of permeate gas on the low-pressure side of the membrane, and therefore improves the flow of permeate through the membrane. In a preferred embodiment, there are three modules. The output streams are taken from the retentate outlet of one module, and from the permeate outlet of another module. The output streams have very high purity, relative to the number of modules required, as compared with systems of the prior art.

A process for removing at least Ca.sup.2+ and Mg.sup.2+ from a lithium-containing brine. The process comprises (i) providing an aqueous lithium-containing brine feed comprising dissolved Ca.sup.2+ and Mg.sup.2+ impurities in a weight ratio of Li.sup.+:Ca.sup.2+ of about 4:1 to 50:1 wt/wt and in a weight ratio of Li.sup.+:Mg.sup.2+ of about 4:1 to 50:1; (ii) subjecting said brine feed to nanofiltration to produce a lithium-containing permeate from which Ca.sup.2+ and Mg.sup.2+ components are being removed concurrently; and (iii) conducting the nanofiltration so that a separation occurs and a retentate solution is formed with a total amount of Ca.sup.2+ and Mg.sup.2+ of at least 75% of the total amount of Ca.sup.2+ and Mg.sup.2+ in the original aqueous lithium-containing brine feed and forming an aqueous lithium-containing permeate solution in which the total content of dissolved Ca.sup.2+ and Mg.sup.2+ is decreased to 25% or less as compared to the original aqueous lithium-containing brine feed.

A mobile processing system is disclosed for the removal of radioactive contaminants from nuclear process waste water. The system is fully scalable, modular, and portable allowing the system to be fully customizable according the site-specific remediation requirements. It is designed to be both transported and operated from standard sized intermodal containers or custom designed enclosures for increased mobility between sites and on-site, further increasing the speed and ease with which the system may be deployed. Additionally, the system is completely modular wherein the various different modules perform different forms or stages of waste water remediation and may be connected in parallel and/or in series. Depending on the needs of the particular site, one or more different processes may be used. In some embodiments, one or more of the same modules may be used in the same operation.