Methods and systems directed to recovery of lithium (e.g., lithium salts) from liquid streams are provided. In some embodiments, methods relate to obtaining lithium (e.g., as a solid lithium salt) by removing at least a portion of liquid from a feed stream to form a concentrated stream with respect to solubilized lithium cations. Liquid removal may include transporting at least a portion of the feed stream to an osmotic unit and/or a humidifier. Some methods include removing impurities (e.g., non-lithium cations) from the concentrated stream (e.g., via precipitation and/or crystallization). In some embodiments, solutions containing solubilized lithium cations and anions are electrochemically-treated such that first solubilized anions are replaced with second, different anions. In some embodiments, solid lithium salt containing at least a portion of the lithium cations and the second anions is obtained (e.g., via precipitation and/or crystallization following concentration of the electrochemically-treated solution in a humidifier).

Methods and systems directed to recovery of lithium (e.g., lithium salts) from liquid streams are provided. In some embodiments, methods relate to obtaining lithium (e.g., as a solid lithium salt) by removing at least a portion of liquid from a feed stream to form a concentrated stream with respect to solubilized lithium cations. Liquid removal may include transporting at least a portion of the feed stream to an osmotic unit and/or a humidifier. Some methods include removing impurities (e.g., non-lithium cations) from the concentrated stream (e.g., via precipitation and/or crystallization). In some embodiments, solutions containing solubilized lithium cations and anions are electrochemically-treated such that first solubilized anions are replaced with second, different anions. In some embodiments, solid lithium salt containing at least a portion of the lithium cations and the second anions is obtained (e.g., via precipitation and/or crystallization following concentration of the electrochemically-treated solution in a humidifier).

A submerged water purification system including a plurality of spiral wound hyperfiltration membrane modules each connected in a parallel flow arrangement to a common feed manifold and a common permeate manifold; wherein each module includes at least one feed spacer sheet and one membrane envelop wound about a permeate collection tube having a plurality of openings along its length that are in fluid communication with the membrane envelop, and further including an end cap secured to an end of the module with a manifold junction reversibly connected to the end cap of each module, wherein the manifold junction provides a sealed fluid communication between the feed spacer sheets and permeate collection tubes of each module to the feed manifold and permeate manifold, respectively.

A submerged water purification system including a plurality of spiral wound hyperfiltration membrane modules each connected in a parallel flow arrangement to a common feed manifold and a common permeate manifold; wherein each module includes at least one feed spacer sheet and one membrane envelop wound about a permeate collection tube having a plurality of openings along its length that are in fluid communication with the membrane envelop, and further including an end cap secured to an end of the module with a manifold junction reversibly connected to the end cap of each module, wherein the manifold junction provides a sealed fluid communication between the feed spacer sheets and permeate collection tubes of each module to the feed manifold and permeate manifold, respectively.

A purification device for water has a housing with a longitudinal axis, an upper and a lower end and a substantially round cross section. The device includes a first receptacle, arranged parallel to the longitudinal axis of the housing, for a first purification medium, and a second receptacle, which is also arranged parallel to the longitudinal axis of the housing, for a second purification medium. The receptacle for the second purification medium is arranged eccentrically with respect to the longitudinal axis of the housing.

A liquid purification system includes a system raw liquid feed unit and a filtration unit, which includes a liquid concentration device having an internal partition dividing a variable volume collection cavity for raw liquid coming from an initial stage of liquid filtration and for mixing therein concentrate and a raw liquid displacement cavity. The cavity is connected to a secondary line that supplies raw liquid to the cavity to displace concentrate from the collection cavity and to recycle raw liquid from the displacement cavity through the secondary line under pressure exerted by concentrate and raw liquid in the collection cavity. A filtration unit provides long-term contact between raw liquid and concentrate in the variable-volume collection cavity to provide smooth increase in the concentration of liquid supplied to a liquid purification device.

A liquid purification system includes a system raw liquid feed unit and a filtration unit, which includes a liquid concentration device having an internal partition dividing a variable volume collection cavity for raw liquid coming from an initial stage of liquid filtration and for mixing therein concentrate and a raw liquid displacement cavity. The cavity is connected to a secondary line that supplies raw liquid to the cavity to displace concentrate from the collection cavity and to recycle raw liquid from the displacement cavity through the secondary line under pressure exerted by concentrate and raw liquid in the collection cavity. A filtration unit provides long-term contact between raw liquid and concentrate in the variable-volume collection cavity to provide smooth increase in the concentration of liquid supplied to a liquid purification device.

A reverse osmosis system includes a membrane unit, an energy recovery device, high and low pressure inlet lines, and a concentrate line. The membrane unit has a membrane, an inlet for receiving a feed fluid, a permeate outlet for discharging a permeate fluid and a concentrate outlet for discharging a concentrate fluid. The energy recovering device has a turbine portion, a turbine inlet and a turbine outlet, a pump portion, a pump inlet and a pump outlet, a motor, and a motor control unit for controlling the motor. The low pressure inlet line is connected to the pump inlet for supplying the feed fluid at a low pressure. The high pressure inlet line connects the pump outlet with the inlet for supplying the feed fluid at a high pressure. The concentrate line connects the concentrate outlet with the turbine inlet for supplying the concentrate fluid to the turbine portion.

A reverse osmosis system includes a membrane unit, an energy recovery device, high and low pressure inlet lines, and a concentrate line. The membrane unit has a membrane, an inlet for receiving a feed fluid, a permeate outlet for discharging a permeate fluid and a concentrate outlet for discharging a concentrate fluid. The energy recovering device has a turbine portion, a turbine inlet and a turbine outlet, a pump portion, a pump inlet and a pump outlet, a motor, and a motor control unit for controlling the motor. The low pressure inlet line is connected to the pump inlet for supplying the feed fluid at a low pressure. The high pressure inlet line connects the pump outlet with the inlet for supplying the feed fluid at a high pressure. The concentrate line connects the concentrate outlet with the turbine inlet for supplying the concentrate fluid to the turbine portion.

A pure water production method for producing pure water by decarboxylating water to be treated under acidic conditions and then deionizing the result by using a reverse osmosis membrane separation device, the pH of inflow water flowing into the reverse osmosis membrane separation device and the water quality of permeated water of the reverse osmosis membrane separation device being measured, and the pH of the inflow water being adjusted on the basis of the measured pH and water quality so that the water quality of the permeated water is within a prescribed range, wherein the pH of the inflow water is changed by a predetermined width, and an operation condition adjusting step is performed for adjusting the pH of the inflow water by comparing the(average value before the water quality change average value after the water quality change.