An ocean alkalinity enhancement (OAE) system that reduces atmospheric CO.sub.2 and mitigates ocean acidification by electrochemically processing feedstock solution (e.g., seawater or brine) to generate an alkalinity product that is then supplied to the ocean. The OAE system includes a base-generating device and a control circuit disposed within a modular system housing deployed near a salt feedstock. The base-generating device (e.g., a bipolar electrodialysis (BPED) system) generates a base substance that is then used to generate the ocean alkalinity product. The control circuit controls the base-generating device such that the alkalinity product is supplied to the ocean only when (1) sufficient low/zero-carbon electricity is available, (2) it is safe to operate the base-generating device, and (3) supplying the alkalinity product will not endanger sea life. Modified BPED systems include features that facilitate autonomous system operations including enhanced maintenance cycle operations and a reduced reliance on external fresh water sources.

Provided, according to one aspect of the present invention, are a sodium hypochlorite production system and a water treatment method using same, the sodium hypochlorite production system comprising: a first means for obtaining saturated brine and purified water using a first sub-stream branching off from a main stream of water to be treated; a second means for obtaining an anodic product and cathodic product by electrolyzing the saturated brine and purified water; and a third means for obtaining sodium hypochlorite by reacting the anodic product and cathodic product using a second sub-stream branching off from the main stream of the water to be treated.

The invention relates to an electrolytic reactor, in particular for separating phosphate from phosphate-containing liquids and/or recovering phosphate salts, comprising an inlet (16) for an electrolysis liquid and a flow channel (20) adjoining same, a magnesium metering unit (12) comprising two electrodes (22, 24) of different polarity being arranged in the flow channel (20), at least one of the two electrodes (22, 24) being a sacrificial electrode (20), wherein the magnesium metering unit (12) is designed as a free-level reactor and a mixing/sedimentation unit (14) being connected downstream of the magnesium metering unit (12) in the direction of flow, said mixing/sedimentation unit having a feed inlet (40) for the phosphate-containing liquids and an outlet (26) for the purified liquid for the obtained phosphate product.

A system comprises an electrodialysis apparatus, which includes first and second reservoirs, wherein a salt concentration in the first reservoir reduces below a threshold concentration and salt concentration in the second reservoir increases during an operation mode. A first electrode comprises a first solution of a first redox-active electrolyte material, and a second electrode comprises a second solution of a second redox-active electrolyte material. In a first reversible redox reaction between the first electrode and first electrolyte material at least one ion is accepted from the first reservoir, and in a second reversible redox reaction between the second electrode and second electrolyte material at least one ion is driven into the second reservoir. A first type of membrane is disposed between the first and second reservoirs, and a second type of membrane, different from the first type, is disposed between the respective electrodes and reservoirs.

An electrochemical system includes a first reservoir comprising a first fluid and a catalyst, wherein the first fluid comprises a reaction mixture that reacts to form first and second products, and a second reservoir comprises a second fluid. A first electrode contacts a redox-active electrolyte material solution and has a reversible redox reaction with the electrolyte material to accept at least one ion. A second electrode contacts a redox-active electrolyte material solution and has a reversible redox reaction with the electrolyte material to drive at least one ion into the second fluid as an electrical potential is supplied. A diluted effluent comprising the second product and the catalyst exits the second reservoir, wherein the second product is removed from the first reservoir via electroosmosis, and optionally concurrently via osmosis, and a product stream comprising the first product exits the first reservoir.

An electrolysis cell and housing provides for simple, toolless cell installation and removal of the electrolysis cell. The electrolysis cell includes an anode and a cathode and requires periodic removal of the electrolysis cell from the housing for cleaning or replacement due to accumulation of deposits on the anode and the cathode. The electrolysis cell includes three push-in fluid connectors and two push-in electrical connections. A filter may be included serially between a water inlet and the electrolysis cell and may include two push-in fluid connectors. A housing rear cover may hold the electrolysis cell and filter in place in the housing and may be removed and reattached to access the electrolysis cell without tools.

Methods and apparatus for controlling electrolysis in an electrolytic cell in order to maintain constant concentration of the disinfectant irrespective of the rate of electrolyte concentration or oxidant production in the electrolytic cell.

An ocean alkalinity enhancement (OAE) system that reduces atmospheric CO.sub.2 and mitigates ocean acidification by electrochemically processing feedstock solution (e.g., seawater or brine) to generate an alkalinity product that is then supplied to the ocean. The OAE system includes a base-generating device and a control circuit disposed within a modular system housing deployed near a salt feedstock. The base-generating device (e.g., a bipolar electrodialysis (BPED) system) generates a base substance that is then tested and processed (e.g., mixed/diluted with processed feedstock solution, seawater or another saltwater solution and/or reacted with CO.sub.2) to generate the ocean alkalinity product. The control circuit controls the base-generating device such that the alkalinity product is supplied to the ocean only when supplying the alkalinity product will not endanger sea life. Modified BPED systems include features that facilitate autonomous system operations including enhanced maintenance cycle operations and a reduced reliance on external fresh water sources.

A method for producing clean water from a contaminated water source, the method comprising the steps of: a) locating a clean water generating device in fluid communication with the contaminated water source, the clean water generating device including a reaction chamber containing an ionic solution; b) transferring contaminated water from the contaminated water source into the reaction chamber through an inlet in the clean water generating device; c) generating an electrolysis reaction within the reaction chamber; d) removing gas generated by the electrolysis reaction from the reaction chamber through an outlet of the reaction chamber; e) combusting the gas generated by the electrolysis reaction; and f) collecting clean water generated by the combustion of the gas.

Contaminants are filtered from a fluid flow stream and the filter is regenerated by a process including steps of: providing a filter material comprising both carbon and potassium iodide; passing a contaminated fluid stream in contact with the filter material; adsorbing contaminants from the fluid stream onto surfaces in the filter material; passing an electric current through the filter material with adsorbed contaminant thereon; disassociating contaminant from the surfaces of the filter material; and removing disassociated contaminant from the filter material by carrying away the disassociated contaminant in a fluid flow mass.