Abstract: Parasitic reactions, such as evolution of hydrogen at the negative electrode, can occur under the operating conditions of flow batteries and other electrochemical systems. Such parasitic reactions can undesirably impact operating performance by altering the pH and/or state of charge of one or both electrolyte solutions in a flow battery. Electrochemical balancing cells can allow adjustment of electrolyte solutions to take place. Electrochemical balancing cells suitable for placement in fluid communication with both electrolyte solutions of a flow battery can include: a first chamber containing a first electrode, a second chamber containing a second electrode, a third chamber disposed between the first chamber and the second chamber, a cation-selective membrane forming a first interface between the first chamber and the third chamber, and a bipolar membrane, a cation-selective membrane, or a membrane electrode assembly forming a second interface between the second chamber and the third chamber.

Abstract: Provided are electrochemical devices that are rechargeable, where the regeneration techniques are based on a batchwise application of current or current density to the cells, where there are a service mode where no current or current density is applied and a recharge mode where a current or current density is applied. Electrochemical and EDI systems according to the embodiments herein are suitable for deionization and/or purification of typical municipal tap quality water in applications where demand for purified, low-TDS water is intermittent. Such operations avoid the use of chemical additions for regeneration purposes. In addition the cells provided herein are amenable to small footprints for consumer and commercial applications such as: dishwashers, washing machines, coffee and espresso makers, ice makers, steam tables, car wash water sources, and steamers.

Abstract: Process and apparatus to remove colloids and nitrogen compounds from contaminated water by coagulating the colloids and separating them from the water. The water is then continuously oxidized with chlorine electrolytically to destroy the nitrogen compounds.

Abstract: 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. Separately, a stable, active iodine solution is also provided for numerous deodorizing and disinfecting applications.

Abstract: Process and apparatus to remove colloids and nitrogen compounds from contaminated water by coagulating the colloids and separating them from the water. The water is then continuously oxidized with chlorine electrolytically to destroy the nitrogen compounds.

Abstract: Disclosed is a method of purifying fluid, typically an aqueous fluid steam, with the method involving at least two reverse osmosis stages with retentate from a first reverse osmosis stage being subjected to the second reverse osmosis stage, and with intermediate treatment of retentate from the first reverse osmosis stage by exposure to an electric field. The intermediate treatment may involve electrocoagulation to remove sparingly-soluble compounds and permit enhanced reverse osmosis recovery. Additional treatment may be performed prior to the first reverse osmosis stage, between the first reverse osmosis stage and the intermediate treatment with an electric field, between such intermediate treatment and the second reverse osmosis stage, or after the second reverse osmosis stage.

Abstract: An apparatus and method for the electrolytic and electrodialytic removal of metal ions from wastewater in a single cell. A battery of cells, each of which consists of a cathode, anode, anion exchange membrane and cation exchange membrane, is used. The battery of cells may be used in both batch and continuous processes, and is capable of reducing metal ion concentration from thousand ppm to few ppm. It can be used to concentrate dilute acids as a by-product.

Abstract: An object of the present invention is to provide an optical measurement apparatus equipped with an ion-exchange resin for pretreating a sample, thereby enabling the concentration of component in the sample to be measured with higher accuracy. The optical measurement apparatus of the present invention includes, in addition to the ion-exchange resin, an optical measurement section for measuring, based on the optical characteristics of the component, the concentration of the component in the sample after the sample is passed through the ion-exchange resin.

Abstract: Animal waste is contacted with an electrolyte containing the oxidized form of one or more reversible redox couples, produced electrochemically by anodic oxidation at the anode of an electrochemical cell. The oxidized forms of any other redox couples present are produced either by similar anodic oxidation or reaction with the oxidized form of other redox couples present and capable of affecting the required redox reaction. The oxidized species of the redox couples oxidize the organic waste molecules and are themselves converted to their reduced form, whereupon they are reoxidized by either of the aforementioned mechanisms. The redox cycle continues until all oxidizable waste species, including intermediate reaction products, have undergone the desired degree of oxidation. The entire process takes place between zero degrees centigrade and slightly below the boiling point of the electrolyte, avoiding formation of either dioxins or furans.

Abstract: Mediated electrochemical oxidation to treats, oxidizes and destroys biological waste, medical, infectious, pathological, animal, sanitary, mortuary, ship, veterinary, pharmaceutical and combined waste. Electrolytes contain oxidized forms of reversible redox couples produced. Oxidized forms of redox couples are produced by anodic oxidation or reaction with oxidized forms of other redox couples. Oxidized species of the redox couples oxidize the biological waste molecules and are reduced and reoxidized. The redox cycle continues until all oxidizable waste and intermediate reaction products have undergone oxidation. Temperatures between ambient and 100° C. avoid formation of dioxins or furans.

Abstract: An electric deionizing apparatus comprising a first and a second electric deionizing apparatus arranged in series, in which water is deionized by the first electric deionizing apparatus and then deionized by the second electric deionizing apparatus, and a means for adding an aqueous electrolyte solution into water released from the first electric deionizing apparatus and which is supplied into the second electric deionizing apparatus. A process for electric deionization comprising supplying water to a first electric deionizing apparatus, deionizing the water in the first electric deionizing apparatus, adding an aqueous electrolyte solution to the deionized water, supplying the deionized water to a second electric deionizing apparatus and deionizing the supplied deionized water in the second electric deionizing apparatus. Silica and boron components in the water are effectively removed to obtain deionized water having a high resistivity.

Abstract: A mediated electrochemical oxidation process is used to treat, oxidize and dispose of biological waste materials. Waste materials are introduced into an apparatus for contacting the waste with an electrolyte, which comprises one or more oxidizing species in their higher valence states in aqueous solution. The electrolyte, which can be regenerated, is used to oxidize specific molecules of the waste materials, breaking them down and preventing the formation of dioxins. The waste treatment process takes place at a temperature range from room temperature up to a temperature slightly below the boiling point of the electrolyte solution (usually the temperature will be below 100° C.), and can be altered by adding ultraviolet radiation.

Abstract: A manufacturing method and apparatus of strongly alkaline ionized water exceeding pH 12.0 by electrolysis of water. As an electrolysis solution supplied to a cathode cell of an electrolytic bath, alkaline ionized water produced in the cathode cell is used, and an operation, in which the alkaline ionized water produced in the cathode cell is circulated and supplied to the cathode cell and is subjected to application of electrolytic voltage, is repeated, so that a cation is accumulated to increase the pH value. As a method for circulating and supplying the alkaline ionized water produced in the cathode cell to the cathode cell, a circulation container bath is used, and the circulation container bath and the cathode cell of the electrolytic bath are connected via a circulating line containing a circulating pump. The circulation container bath has a withdrawing system containing a water collecting device for withdrawing alkaline ionized water having a desired pH value to the outside.

Abstract: A device for producing ion water comprises an electrolytic cell; two partition walls disposed such that the electrolytic cell is partitioned into three electrolytic chambers, having an ion exchange membrane; an anode provided in an intermediate electrolytic chamber of the electrolytic cell such that the anode is attached fixedly or movably in the direction of the electrolytic chambers located at both sides of the electrolytic cell; and a cathode provided in each of the electrolytic chambers located on both sides of the electrolytic cell such that the cathode is attached fixedly or movably in a direction such that the distance between the anode and cathode changes, each cathode being fed half the amount of electric current which is delivered to the anode, so that the desired pH of three kinds of ion water can be achieved by controlling the quantity of hydrogen ions generated as determined by the amount of electricity delivered.

Abstract: Stainless steel pickling process in which a pickling solution containing HF and Fe3+ ions as essential components is used, and wherein the oxidation to Fe3+ of the Fe2+ formed during the process in order to maintain the Fe3+ concentration to the predetermined value, is electrolytically carried out by submitting the pickling solution as it is to an oxidation process in an electrolytic cell equipped with anode made of inalterable materials chosen among graphite, granular coal, lead and with cathodes made of stainless steel, graphite or other unalterable materials, said cell working with an applied tension between 1 and 8 V and with an anodic current density between 0.4 and 15 A/dm2.

Abstract: An increasing problem with the pulping chemical recovery system, is the presence of chloride and potassium in the recovery boiler. Chloride and potassium increase inter alia the stickiness of carryover deposits and dust particles to the recovery boiler tubes, which accelerate fouling, corrosion and plugging of the recovery boiler. As the environmental legislation becomes more stringent, the degree of system closure increases. The present invention relates to a process by which the collected precipitator dust is leached, at a temperature exceeding 50.degree. C., for a residence time sufficient to get a chloride and potassium enriched leach solution and to remove at least a part of the content of metal ions in a solid phase. Said leach solution is electrochemically treated, preferably in an electrodialysis cell, in order to remove at least a part of the chloride and potassium therein. By the present process, the problem of sticky deposits in the recovery boiler can be substantially reduced.

Abstract: An electrochemical cell with a Co(III) mediator and nitric acid electrolyte provides efficient destruction of organic and mixed wastes. The organic waste is concentrated in the anolyte reservoir, where the mediator oxidizes the organics and insoluble transuranic compounds and is regenerated at the anode until the organics are converted to CO.sub.2. The nitric acid is an excellent oxidant that facilitates the destruction of the organic components. The anode is not readily attacked by the nitric acid solution, thus the cell can be used for extended continual operation without electrode replacement.

Abstract: An electrochemical leaching system for cleaning contaminated fines. The system has a waste vessel for receiving and holding a contaminated fines and lixiviant mixture. On a side of the waste vessel is an anolyte vessel holding an anolyte fluid. An anolyte barrier separates the waste and anolyte vessels. On an opposite side of the waste vessel is a catholyte vessel holding a catholyte fluid. A catholyte barrier separates the waste and catholyte vessels. A potential between an anode in the anolyte vessel and a cathode in the catholyte vessel ionizes the fines contaminants into anionic and cationic contaminants in the lixiviant. The anolyte and catholyte barriers allow the anionic and cationic contaminants, respectively, to flow from the lixiviant and into the anolyte and catholyte fluids in their respective vessels without allowing bulk transfer therebetween. The anionic and cationic contaminants are then removed from the anolyte and catholyte fluids. A cleaner lixiviant and fines exits the system.

Abstract: This invention is related to a process for producing pulp from a cellulosic starting material, wherein an aqueous process effluent is purified from metal impurity cations. This process comprises that the effluent is purified by an electro-chemical membrane treatment in an electrochemical membrane device comprising a unit cell through which an electric current is passed between an anode side and a cathode side of said cell, said cell comprising at least two ion permeable membranes forming between them at least one compartment, said effluent being fed into an effluent feed compartment in said cell, in which the effluent is purified by removing with the electric current metal impurity cations from the effluent through a cation selective membrane on the cathode side of said compartment, and withdrawing from said compartment the purified effluent. The purified effluent may be recirculated to the pulp mill process, e.g. as washing water.

Abstract: An electrochemical cell (20) which is effectively leakproof and can be incorporated into an easily serviceable cell pack (80). Within the cell are a plurality of parallel electrode plates (44, 46, 56) which act as anode and cathode reaction surfaces for processing chemicals. The electrochemical cell housing (33) is preferably formed of durable plastic with all fluid inlets (36, 38) and outlets (40, 42) on its upper face (30). One or more input manifolds (48, 50) are provided to route process chemicals to the bottom of the cell and then distribute them upward across the electrode plates. The housing is formed as a one-piece, monolithic structure with an opening left on top for fitting the top face. At the end of cell assembly, the top face is attached to the remainder of the cell housing so as to form a sealed cell.

Abstract: An improvement is proposed in the cleaning treatment of semiconductor silicon wafers in which the conventional step of cleaning with an aqueous solution of an acid is replaced with a cleaning treatment with a temporarily acidic pure water which is produced electrolytically by the application of a DC voltage between an anode and a cathode bonded to the surfaces of a hydrogen-ion exchange membrane so that the acidic cleaning treatment can be performed under mild conditions so as to eliminate the troubles unavoidable in the conventional process. The apparatus used therefor comprises a rectangular vessel partitioned into a central anode compartment, in which the wafers are held in a vertical disposition within an upflow of pure water, and a pair of cathode compartments on both sides of the anode compartment by partitioning with a pair of hydrogen-ion exchange membranes, on both sides of which an anode plate and a cathode plate are bonded.

Abstract: An improvement is proposed in the cleaning treatment of semiconductor silicon wafers in which the conventional step of cleaning with an aqueous solution of an alkali is replaced with a cleaning treatment with a temporarily alkaline pure water which is produced electrolytically by the application of a DC voltage between a cathode and an anode bonded to the surfaces of a hydrogen-ion exchange membrane so that the alkaline cleaning treatment can be performed under mild conditions so as to eliminate the troubles due to formation of COPs unavoidable in the conventional process. In addition, the pure water rinse following the alkali cleaning of the wafers before transfer to the succeeding acidic cleaning step can be omitted to greatly contribute to the improvement of productivity.

Abstract: The method for producing electrolyzed water includes the step of applying a voltage to electrodes disposed in an electrolytic cell containing therein pure water including electrolyte therein. A strength of an electric field generated by applying a voltage to the electrodes is controlled to be variable by means of various techniques. The method makes it possible to produce electrolyzed water with a smaller amount of energy than prior methods.

Abstract: The invention relates to a process for treating a low-concentrated aqueous feed solution which includes at least one aqueous process stream from a pulp mill. The process includes concentrating the feed solution by evaporation to form an evaporation concentrate, and subjecting at least a part of the concentrate to a first electrodialysis treatment, thereby forming a first electrodialysis concentrate containing salt removed from the evaporation concentrate and at least one diluate depleted in the salt. The invention also relates to a plant for carrying out the above process.