A hollow fiber membrane bundle useful for manufacturing a wide variety of hollow fiber membrane modules having different flow configurations includes hollow fiber membranes arranged around a porous support tube, a cured resin tubesheet formed at first end of the bundle, and either a cured resin nub or a cured resin tubesheet formed at a second end of the bundle. The bore(s) of the hollow fiber membranes are open at a face of the tubesheet adjacent the first end of the bundle. The tubesheet has an annular structure that encapsulates the hollow fiber membranes and the porous support tube at the first end of the bundle but which does not completely block a bore of the porous support tube, wherein the collection tube has a plurality of orifices formed therein at least at positions adjacent the nub.

A hollow fiber membrane bundle useful for manufacturing a wide variety of hollow fiber membrane modules having different flow configurations includes hollow fiber membranes arranged around a porous support tube, a cured resin tubesheet formed at first end of the bundle, and either a cured resin nub or a cured resin tubesheet formed at a second end of the bundle. The bore(s) of the hollow fiber membranes are open at a face of the tubesheet adjacent the first end of the bundle. The tubesheet has an annular structure that encapsulates the hollow fiber membranes and the porous support tube at the first end of the bundle but which does not completely block a bore of the porous support tube, wherein the collection tube has a plurality of orifices formed therein at least at positions adjacent the nub.

Described herein are methods of recovering lithium from dilute lithium sources. The methods include extracting lithium from an extraction feed using direct lithium extraction in an extraction stage to yield a lithium intermediate, performing one or more concentration operations, each concentration operation concentrating an input stream to yield an output feed, wherein the input stream is obtained from the lithium intermediate and/or the extraction feed is obtained from the output feed. At least one of the concentration operations includes a membrane separation operation having a plurality of reactors in series each having a semi-permeable membrane, such as a counter-flow reverse osmosis operation. Methods may also include generating a low TDS stream as a permeate from any of the one or more concentration operations, wherein the low TDS stream is recycled or used as fresh water.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

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.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Lithium recovery processes are described using concentration and conversion techniques. A vaporizer or membrane can be used to concentrate lithium and precipitate impurities. A conversion process can be used to replace anions in lithium bearing streams by adding a second anion and precipitating lithium in a salt with the second anion. Rotary separation can be used to separate the precipitated lithium salt.

An apparatus for reverse osmosis, the apparatus comprising: a single-stage reverse osmosis (SSRO) unit; and a counter-current membrane cascade with recycle (CMCR) unit comprising a plurality of stages of reverse osmosis including at least a first stage and a second stage wherein permeate from the first stage is configured to be introduced as feed to the second stage; wherein retenate from the SSRO unit is configured to be introduced as feed to the first stage, and wherein product obtained using the apparatus comprises permeate from the SSRO unit and permeate from a last stage of the CMCR unit.