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, systems, and apparatus, relate to a method for carbon capture from sea water. A first source of sea water into a reverse osmosis chamber. Reverse osmosis is performed on the sea water to produce fresh water and brine. The brine is provided to an electrolyzer. A current is passed through the brine and fresh water, thereby producing a hydroxide solution in a cathode chamber of the electrolyzer. The hydroxide solution is collected and placed into a contacting chamber and new sea water introduced. Precipitates are produced comprising at least calcium carbonate and magnesium carbonate.

Disclosed herein is an electrostatic precipitation method using an electrostatic precipitator including a collection module having a collection electrode and a discharge electrode, a housing having an internal partition wall formed therein, an inlet-side passage switching member, and an outlet-side passage switching member. The electrostatic precipitation method includes collecting dust by applying a voltage to the discharge electrode while gas flows, closing some of the flow spaces, divided by the internal partition wall using the passage switching members, and performing dust collection for one of the opened flow spaces by applying a voltage to the discharge electrode therein, and performing washing for at least one of the closed flow spaces by supplying washing water to the collection electrode therein.

Provided are electrodialysis systems for removing silica from a desalinated water stream and methods for removing silica from a desalinated water stream. For example, described are bipolar membrane electrodialysis devices for removing silica from water comprising one or more anion exchange membranes; one or more bipolar membranes; and a pair of electrodes comprising a positive electrode and a negative electrode. Also described are electrodialysis systems comprising: one or more electrodialysis devices for the removal of dissolved ions and one or more bipolar membrane electrodialysis devices, wherein a product inlet stream of the one or more bipolar membrane electrodialysis devices comprises the product outlet stream of the one or more electrodialysis devices.

A water remediation system and accompanying method includes remediation by reducing the concentration of nutrients in the water and dosing the water with metal ions. It has been found that through a combination of reducing nutrients present in the water and treating with metal ions, the requirement to treat with high chemical dosages is removed.

A method and an arrangement for removing amine(s) from a thickener overflow of a mineral processing plant. The method includes supplying the thickener overflow to an electrocoagulation unit and subjecting the thickener overflow to electrocoagulation in order to separate at least some of the amine(s) as an electrocoagulation overflow and in order to form a residual process water as an electrocoagulation underflow, and removing the electrocoagulation overflow. The method is free of all of the following: a coagulant, a flocculant, an adsorbent and an additional flotation chemical.

A method for circulating hot air in a solar desalination system includes providing a desalination structure having an air flow path defined between an external surface layer and an internal surface layer. A return flow conduit provides an internal fluid flow path. Saline water is pumped through a center column in a direction from the base towards the peak. The saline water is delivered through a nozzle that extends through a sidewall of the center column to provide a mist within the desalination structure exterior of the center column. An air flow within the air flow path is heated to form a hot air supply. The mist is heated with the hot air supply to form an evaporated fluid. A diverted portion of the hot air supply is delivered into the return flow conduit and mixed with an ambient air to form and heat the air flow.

Provided are a biomineralogical method for removing cesium ions. The method for removing cesium ions, the method comprising: adding metal-reducing bacteria, an iron source, and a sulfur source into a solution containing the cesium ions to convert the cesium ions into a solid mineral incorporating cesium. The method for removing cesium ions according to the present invention has advantages in that the cesium ions may be removed with high efficiency and small volume even in the case in which competing ions are present at a high concentration like sea water.

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.

Described herein is a functional graphene composition comprising a graphene scaffold and one or more metal chelating functional groups covalently bonded to the graphene scaffold and a porous substrate that includes the functional graphene composition. Also provided is a method of removing dissolved metals from an aqueous liquid, such as, acid mine drainage.