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.

According to one embodiment, there is provided a carbon dioxide fixation system includes an electrolytic cell and a settling tank. An electrolytic cell electrolyzes seawater to generate sodium hydroxide (NaOH). A settling tank mixes the sodium hydroxide generated in the electrolytic cell, concentrated seawater, and carbon dioxide (CO.sub.2) to precipitate magnesium carbonate in which the carbon dioxide is fixed to magnesium (Mg) contained in the concentrated seawater.

The present invention relates to a water heat dissipating system used for a condenser coil of a water filter apparatus, the system comprising: said condenser coil of the water filter apparatus including a bent refrigerant pipeline part with a suitable shape for transferring heat from refrigerant conducted by the condenser coil to outside; a water heat dissipating container for containing water therein, the water heat dissipating container having a water heat dissipating container inlet and a water heat dissipating container outlet to circulate water contained in the water heat dissipating container. The bent refrigerant pipeline part is arranged inside the water heat dissipating container for transferring heat from refrigerant conducted inside the bent refrigerant pipeline part to water contained in the water heat dissipating container. The water heat dissipating container inlet is connected to at least a waste water outlet of a RO filter cartridge (Reverse Osmosis) of the water filter apparatus. The present invention also relates to a water filter apparatus using the water heat dissipating system.

Methods and systems for treating a waste substance containing perfluoro- and polyfluoroalkyl substances (PFAS) and mineralizing the PFAS, at least partially. The method includes combining the PFAS with a first amendment in a reactor to create a combination, heating and pressurizing the combination to hydrothermal conditions, and holding the combination at hydrothermal conditions for a holding time sufficient to at least partially mineralize the PFAS to create a treated combination.

The present invention relates to a method for recovering N, K, and P from liquid waste stream, preferably from a stream of urine, or from a stream comprising excreta (e.g. faeces, manure, digestate, fertilizer), or from (concentrated) wastewater, for example, municipal (e.g. sewage, septic) and/or industrial wastewater (e.g. food and feed industry, agriculture, mining, etc.); more preferably from urine, such as human or animal urine; most preferably from human urine.

The present specification provides a composition comprising a material of Chemical Formula 1: ##STR00001##
having a molecular weight of 500,000 to 700,000 where R1 and R2 are the same as or different from each other, and each independently is hydrogen, deuterium, or an alkyl group, and n is from 10,000 to 20,000, for forming a reverse osmosis membrane protective layer, a method for preparing a reverse osmosis membrane using the same, a reverse osmosis membrane and a water-treatment module.

A method for LiOHH.sub.2O production from lithium-bearing multicomponent hydromineral raw materials includes filtering lithium-bearing brine contaminated with suspended particles with regeneration of filters and processing of used regenerate, and obtaining pregnant lithium-bearing brine, isolation of lithium chloride from the brine in the form of a primary concentrate in sorption-desorption modules, and nanofiltration of the primary lithium concentrate from magnesium, calcium and sulfate ions. By means of reverse osmosis, electrodialysis concentration and ion-exchange purification from impurities followed by thermal concentration, the primary lithium concentrate is converted into a pregnant lithium chloride concentrate which is converted into a LiOH solution by membrane electrolysis. The LiOH solution is boiled down, resulting in LiOH.H.sub.2O crystallization.

A method of extracting lithium from a lithium-containing solution according to an exemplary embodiment of the present invention includes: obtaining a lithium chloride solution from the lithium-containing solution; and crystallizing and removing sodium chloride in the obtained lithium chloride solution.

Disclosed is a system for producing magnesium hydroxide including: a generation unit; and a recovery unit connected to the generation unit, wherein the generation unit has a reaction tank in which a calcium hydroxide slurry is added to water to be treated containing magnesium ions to crystallize magnesium hydroxide and to obtain a reaction slurry containing particles of magnesium hydroxide, and a sedimentation tank in which the reaction slurry is reserved to sediment the particles and to separate the reaction slurry into a separation slurry containing the particles at a high concentration and a separation liquid containing the particles at a low concentration, and wherein, in the recovery unit, an alkaline aqueous solution is added to the separation liquid to crystallize magnesium hydroxide and to obtain the reaction slurry and then the reaction slurry is reserved to sediment the particles and to recover the sedimented particles.

A system for producing magnesium chloride includes a removal unit, and a concentration unit that is connected to the removal unit. The removal unit generates feedstock water by removing sulfate ions and sodium ions from treatment target water having seawater as a feedstock. The concentration unit generates a slurry in which magnesium chloride is crystallized by concentrating the feedstock water. The removal unit has a first removal unit which reduces the sulfate ion concentration compared to the sulfate ion concentration in the treatment target water, and a second removal unit which reduces the sodium ion concentration compared to the sodium ion concentration in the treatment target water.