Abstract:
Electrodeionization methods and apparatus wherein ion exchange membranes are not utilized. Instead, ion exchange materials such as beads, fibers, etc., are disposed in alternating layers of anion exchange (AIX) materials and cation exchange (CIX) materials between opposite polarity electrodes. In a regeneration stage, a current is applied across the electrodes with water splitting occurring along at least one of the interfacial areas between neighboring AIX and CIX materials. The H+ and OH− ions formed via water splitting migrate in response to the electrical current and displace the salt ions in the respective AIX and CIX. The stack is flushed during the regeneration stage to remove the concentrated salt solution. During a deionization phase, the electrical current is terminated with influent fed to the stack for deionization. The salt ions in the influent are depleted via ion exchange as the influent contacts the AIX and CIX.
Abstract:
The invention comprises water desalination methods and a system for such, which includes treatment of water in cation and anion ion exchange columns, and regenerating the columns after treatment of the water to set them up again for a further treatment cycle, and also providing recoverable by-products during the regeneration of the ion exchange columns instead of waste.
Abstract:
In a method and apparatus for operating and regenerating ion exchange material a wash fluid or elution solution for rinsing the ion exchange material (1) is prepared, there is collected as a by-product of said preparation a first waste stream including cationic species to be eliminated, the ion exchange material (1) is subjected to a wash step in which there is eluted from the ion exchange material by the wash fluid or solution an anionic species to be eliminated and a second waste stream including the anionic species to be eliminated is obtained, the first waste stream (12) and the second waste stream (14) are combined to form a precipitate SW comprising a reaction product of said cationic species and said anionic species, and the precipitate is removed. The method provides an efficient means of eliminating undesired species from a circuit containing an ion exchange material to be regenerated.
Abstract:
The present invention provides a multiple bed-type condensate demineralization method and apparatus for the method that are able to provide an improved treated water quality in ammonia operation by substantially reducing the cross contamination ratio during resin regeneration from the current cross contamination ratio. In the method of condensate demineralization using ion-exchange resin in a multiple-bed regime, condensate is passed through a resin layer having a multiple-bed structure in which an anion resin layer and a layer of a uniform particle size strong acid gel-type cation resin with a 10% to 16% degree of crosslinking, divided by a partition in such a manner that they do not mix with each other, are combined in alternation. The uniform particle size strong acid gel-type cation resin with a 10% to 16% degree of crosslinking is an ion-exchange resin that has a uniform particle size of 500 to 800 μm for which at least 95% of the resin particles fall in the range defined by the average particle size ±100 μm and the uniformity coefficient is less than or equal to 1.2. Ion-exchange resin that has come to require chemical regeneration is separately withdrawn and subjected to chemical regeneration by type and is returned into the originating partition.
Abstract:
A process for fluoride removal from wastewater streams produced during industrial operation for further industrial use or to comply with environmental regulations. The process segregates the removal of fluoride and fluorosilicate ions, from the totality of ions in the waste water stream, thus improving treatment efficiency and reducing costs. Ion-exchange chromatography is used to remove the fluoride and fluorosilicate ions by passing the wastewater stream through one or more columns that contain a charged resin which selectively binds cations/anions in the stream. The fluoride ions are washed from the column and then collected for removal or use in other processes.
Abstract:
A method and apparatus for producing deionized water by passing water to be treated through a deionizing and water treatment system having carbon filtration and beds of packed ion exchange resins, specifically including beds of mixed anion resins, so that sediment and impurity ions are removed as adsorbed on the ion exchange sites of the resins and a method of regenerating the ion exchange resins after having its ion-exchanging and adsorbing abilities lowered.
Abstract:
An ion exchange system for use in purifying sweetener solutions manufactured in a corn wet milling plant and a method of operating the system. The sweetener solution is passed under pressure through a plurality of ion exchange unit pairs configured to operate in both a parallel and series configuration. This configuration and method of operation has resulted in increased hydraulic capacity, a reduction in system operating pressures, an increased efficiency of impurity adsorption and an increase in the time between regeneration cycles.