A process for preparing a hollow fiber includes the steps of providing a dope solution including polyamide imide (PAI), providing an aqueous bore solution including polyethylene imine (PEI), extruding the dope solution in an cross-sectional annular shape and ejecting the bore solution in the center of the annular shape, allowing the PAI and the PEI to react, thereby forming an internal surface layer including the cross-linked reaction product, and forming a polyamide Thin Film Composite (TFC) layer by interfacial reaction of aqueous di- or triamine compound and organic di- or triacylhalide compound on the internal surface layer including the cross-linked reaction product.

Disclosed herein are apparatuses and methods for semi-permeable membrane cleaning. In particular, a pressure retarded osmosis (PRO) process redirects raw solution and fluid streams in such a way as to cause periodic changes of the process from PRO to reverse osmosis (RO) for lifting and detaching fouling. Further disclosed is applying, at least periodically, a pulsed-flow regime in the fluid stream, thereby causing increased shearing force for enhanced evacuation of the foulant. Additionally, a backward wash may be provided by injection, for a predetermined injection time, of additional solution selected in such way that net driving pressure becomes RO opposite to normal PRO operation, thereby providing a backward flow from a first side of the membrane to a second side of the membrane, so as to lift and evacuate foulant.

A hollow fiber membrane module includes one pressure vessel, and at least one hollow fiber membrane element loaded in the pressure vessel. Each of the element includes a plurality of hollow fiber membranes each having openings at both ends, a bypass tube, and a supply port and a discharge port provided on one end side in a longitudinal direction. The supply port is in communication with inflow-side openings of hollow fiber membranes. The bypass tube is provided in the longitudinal direction of the element, has an inflow port at an end portion on a side of outflow-side openings of the hollow fiber membranes, and has an outflow port at an end portion on a side of the inflow-side openings of the hollow fiber membranes. The outflow-side openings of hollow fiber membranes are in communication with the inflow port, and the outflow port is in communication with the discharge port.

A concentrated spent dialysate is produced for by reducing electrolytes in a spent dialysate by electrodialysis and de-watering the spent dialysate by a forward osmosis operation.

A hemodialysis treatment apparatus has an ultrafiltration unit for exchange of solutes of a patient's blood plasma and a dialysate, resulting in a stream of cleaned blood for returning to the patient and a stream of spent dialysate. An electrodialysis device reduces electrolytes in the spent dialysate. A forward osmosis unit with a membrane having a feed side and a draw side that is allows only water to permeate. A stream of spent dialysate from the ultrafiltration unit is in fluid communication with the feed side and a stream of concentrated dialysate is in fluid communication with the draw side. A stream of dialysate results. Blood plasma is pumped from the patient to the ultrafiltration unit.

Provided herein is forward osmosis-based water purification process, that includes contacting a solution of a soluble draw agent with a dehydrated insoluble draw agent, separating the now hydrated insoluble draw agent from the now concentrated draw solution, and exerting a stimulus on the hydrated insoluble draw agent for extracting water therefrom, thereby regenerating a dehydrated insoluble draw agent, wherein the osmotic concentration (osmolality) of the insoluble draw agent is greater than the osmotic concentration of the diluted draw solution, and the insoluble draw agent is impermeable to the soluble draw agent.

The present teaching relates to method, system, medium, and implementations for storage management. A hash table is constructed, having an index file having one or more slots, each of which includes one or more buckets. Each bucket stores one or more types of records, including a direct record, an indirect record, and a forwarding record. A direct record stores data directly in a bucket of a slot of the index file. When a storage request is received related to some relevant data, the request is handled based on the constructed hash table.

A method for separating ionic species from an analyte solution to form a fractionated sample, the method comprising contacting the analyte solution with an ion-exchanger that is selectively permeable to ionic species of either a positive or negative charge, contacting an opposing side of the ion-exchanger with a draw solution, wherein the draw solution comprises adsorber particles dispersed in a liquid carrier, establishing a concentration gradient across the ion-exchanger to allow at least some ionic species from the analyte solution to permeate through the ion-exchanger to the draw solution, adsorbing ionic species that permeate from the analyte solution onto the adsorber particles, separating adsorber particles having the ionic species adsorbed thereto from at least part of the draw solution, and eluting the ionic species from the separated adsorber particles to form a fractionated analyte sample comprising eluted ionic species.

An induced symbiotic osmosis system and method for treating produced fluids from a hydraulic fracturing process or system for symbiotic fluids fractionation, salinity power generation, brines and salts solution reverse osmosis. The system includes a reverse osmosis membrane assembly to create potable water from produced water. The membrane assembly includes a hollow fiber or flat sheet membrane and headers to transfer desalinated water therefrom. The system can include an electro coagulation system, an ultra or nano filtration system, and a desalter to treat the produced water or brine. A heat exchanger can be positioned between adjacent reverse osmosis membrane assemblies. An osmotic power generation unit can create electrical power by receiving and utilizing produce water and brine water from a brine storage. The system reduces the release of global warming contributing gases associated with hydraulic fracturing, while producing potable water and power.

An example separation system includes a stack of membrane plate assemblies. An example membrane plate assembly may include membranes bonded to opposite sides of a spacer plate. The spacer plate may include a first opening in fluid communication with a region between the membranes, and a second opening in fluid communication with a region between membrane plate assemblies. Adjacent membrane plate assemblies in the stack may have alternating orientations such that bonding areas for adjacent membranes in the stack may be staggered. Accordingly, two isolated flows may be provided which may be orthogonal from one another.

A system includes an electrodialysis device with a salinate chamber through which a salinate stream flows. A desalinate chamber is separated from the salinate chamber by a central, ion-selective membrane. A desalinate stream flows through the desalinate chamber. An anolyte chamber and a catholyte chamber are on opposite outer sides of the salinate and desalinate chambers and separated therefrom by first and second ionic exchange membranes. A solvent exchange interface is in contact on a first side with the salinate stream and is in contact a media flow on a second side. The solvent exchange interface moves a solvent from the media flow to the salinate stream.