Abstract: Disclosed is a water softener capable of producing soft water at various temperatures and facilitating the regeneration of an ion exchange resin thereof. The water softener includes a water softening tank in which an internal region containing therein the ion exchange resin is partitioned into a plurality of water softening regions which are individually assigned into a predetermined temperature; a regeneration tank integrated with the water softening tank into a single body and containing the regeneration material of the ion exchange resin; a cold/hot control valve to supply raw water to a selected one of the plurality of water softening regions according to the temperature of the raw water to rapidly supply the soft water at a desired temperature to a user; and a regeneration valve to facilitate the periodic regeneration of the ion exchange resin through a simple manual operation.

Abstract: This invention relates to a bioprocess engineering solution for a product removal process for use in a biofermentation. The invention discloses a process for withdrawing an aliquot of broth from a biofermentation vessel during at least a portion of the biofermentation, removing biocatalyst and water, chromatographically separating biofermentation products from the withdrawn broth using water as an eluent, and returning the remaining components of the broth back to the biofermentation vessel. Process chromatography permits highly selective separation of the target molecule, preventing feedback inhibition of the biofermentation.

Abstract: The present invention provides a process for enhancing the metal contaminant sorption capacity of mineral compounds within a groundwater-bearing formation by manipulating the pH and the surface acidity of the mineral compounds. The process is useful in removing metal contaminants from groundwater within a groundwater-bearing formation, providing a backstop treatment for groundwater after previous water treatment, and for protection of water sources, for example well-head protection.

Abstract: Apparatus and method are disclosed for introducing ion exchange or other particulates into compartments of an already-assembled electrodeionization or comparable stack by modulating a flow of slurry into the compartments with slugs of gas such as air. The air propels liquid through the cells, scavenging ponded liquid so that the particulates (which are retained, e.g., by a strainer or obstruction, in compartment of the apparatus) are deposited as well-packed beds to fill the compartments. Pressurized air filling protocols may deliver discrete slugs of slurry between bursts of air, and the direction of filling may be periodically reversed to diminish particle bed non-homogeneities or settling gradients that arise during transport. The slugs of air may be applied in the direction of slurry flow, in the reverse direction, or both. Different slurries may be transported in a sequence to form layered and packed beds of enhanced utility.

Abstract: The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

Abstract: A method of regenerating an ion exchange resin, comprising the steps of packing a used ion exchange resin in a regeneration tower; and repeating at least twice a step comprising passing an aqueous solution of regenerant through the regeneration tower downward from a top part of the regeneration tower and thereafter passing ultra-pure water through the regeneration tower upward from a bottom of the regeneration tower. This method enables regenerating an ion exchange resin efficiently and homogeneously without mixing of the regenerant into ion exchange resin towers for purification.

Abstract: An ion exchange process for removing arsenic from drinking water is disclosed which uses a mixed ion regenerant and generates minimal levels of waste.

Abstract: An object of the present invention is to provide a structure of a metal collecting material for use in seawater or river water or industrial wastewater to give the most excellent adsorption efficiency. Another object of the present invention is to provide a process for efficiently separating and recovering valuable metals or noxious metals from a metal collecting material having collected said valuable metals from seawater or noxious metals from river water or wastewater with the least possible waste generation. A metal collector according to an aspect of the present invention is formed by stacking at least partially alternate layers of a fibrous metal collecting material with a spacer for introducing a liquid to be treated into said collecting material, wherein the area of spacer side faces represents 25-75% of the total area of collecting material side faces and spacer side faces in the side faces of the stack.

Abstract: A method of coacting a fluid with a media, such as granular particles. The media is moved to an upper portion in an upright media container, and held there during a treatment cycle in which the fluid is coacted with the media. When the media requires regeneration, the media is allowed to fall to a lower portion of the media container where a regeneration fluid is passed through the media.

Abstract: The present invention aims at inhibiting a lowering in the modification ratio of a modified cation-exchange resin, in which part of the sulfonic acid groups have been modified with a thiol-containing amine compound and which is employed as a catalyst for producing bisphenol, during preservation. In the present invention, a modified cation-exchange resin is packed together with water into a container while regulating the surface area of the container to 0.5 m2 or less per liter of the resin and then the container is sealed up so that the resin is preserved in a state of being soaked in water.

Abstract: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

Abstract: By passing an alkali regenerating agent A through a basic anion exchange resin (3), and through a strongly acidic cation exchange resin (4), the basic anion exchange resin can be regenerated while amphoteric organic materials such as the amino acids captured at the strongly acidic cation exchange resin can be desorbed. Then, an acid regenerating agent B is passed through the strongly acidic cation exchange resin to regenerate the strongly acidic cation exchange resin.

Abstract: The invention relates to a method for rendering waste sorbent material recyclable. The method includes collecting polymer-based sorbent materials containing one or more solvents, treating the waste material in a centrifugal treatment system for removing the solvents from the polymer-based sorbent materials whereby the sorbent materials have a residual solvent content that renders the materials non-hazardous for transportation to a remote recycling site. The treatment system includes a fume collection system and a centrifuge disposed in the fume collection system. The sorbent materials are charged into the centrifuge and the centrifuge is operated for extractive removal of solvents therefrom and collection of the extracted solvents. The sorbent materials are rendered non-hazardous by the centrifugal treatment system enabling the materials to be taken off site for use in making recycled parts.

Abstract: By passing an alkali regenerating agent A through a basic anion exchange resin (3), and through a strongly acidic cation exchange resin (4), the basic anion exchange resin can be regenerated while amphoteric organic materials such as the amino acids captured at the strongly acidic cation exchange resin can be desorbed. Then, an acid regenerating agent B is passed through the strongly acidic cation exchange resin to regenerate the strongly acidic cation exchange resin.

Abstract: A method of coacting a fluid with a media, such as granular particles. The media is moved to an upper portion in an upright media container, and held there during a treatment cycle in which the fluid is coacted with the media. When the media requires regeneration, the media is allowed to fall to a lower portion of the media container where a regeneration fluid is passed through the media.

Abstract: An ion exchange resin comprising an ion exchange material dispersed or distributed throughout a polyurethane matrix. The ion exchange material is typically a second polymer which has been chemically modified after dispersion or distribution throughout the polyurethane matrix.

Abstract: A process is disclosed for the recovery of gold and/or silver values from activated carbon, wherein they are adsorbed as cyanide complexes. The process uses an eluant containing sugar. The process allows the eluant to pass through fresh carbon twice, thereby reducing the volume of the gold-loaded eluant. This, in turn, reduces the size of the electrowinning or zinc precipitation circuits. The process also improves elution efficiency when barren electrowinning solution is recycled in the elution process.

Abstract: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

Abstract: A method and an apparatus for performing a continuous reaction with at least one liquid reaction phase incorporating at least one starting compound in the presence of at least one solid-phase catalyst, wherein the phases to be contacted are circulated through at least one pulsed reaction column (1). The liquid reaction phase is continuously fed into the middle or lower portion of the pulsed column (1), the liquid phase is circulated upwards through the pulsed column (1), and a counterflow made up of lumps (9) of a solid selective extraction compound is continuously circulated. Furthermore, each solid catalyst is continuously circulated through the pulsed column (1) in contact with the liquid phase.

Abstract: A method for cleaning ion exchange resins. The ion exchange resin is circulated by a circulating medium within a circulation, system. The concentration of ions within a circulation medium is periodically changed at a selected point in the circulation system to change the amount of solution within the ion exchange for a period of time such that the amount of solution within the ion exchange resin fluctuates as the ion exchange resin circulates within the circulating system. The degree of cleaning of the resin an the quantity of chemicals required are both improved. Additionally, the ion exchange resin may be agitated for further cleaning.

Abstract: A water treating apparatus is provided which can treat waste water for use as raw water in an ultrapure water producing system without addition of various kinds of chemicals. The apparatus includes a first water tank for receiving acid waste water, a second water tank for subjecting the waste water from the first water tank to solid-liquid separation and discharging supernatant liquid, an ion exchange tank including ion exchange resin and an aeration tube for generating treated water through a membrane filter, a precipitation tank for settling ion exchange resin, an air lift pump for introducing ion exchange resin from the precipitation tank into the first water tank, and a return air lift pump for returning ion exchange resin from the second water tank to the ion exchange tank. The ion exchange resin acts to exchange ions with fluorine ions of treated water in the ion exchange tank and is regenerated by acid waste water in the first water tank.

Abstract: An apparatus for continuously separating ion exchange resin particles with upwardly flowing carrier fluid. The apparatus includes a first vertically oriented separation vessel and a first collection vessel for receiving the first fraction of resin particles from the upper zone of the first separation vessel. A first rejuvenation tank is connected to the first collection vessel for receiving the first fraction of resin particles from the first collection vessel. In the preferred embodiment, the apparatus further includes a second vertically oriented separation vessel and a second collection vessel for receiving the first sub-fraction of the second fraction of resin particles from the upper zone of the second separation vessel.

Abstract: It is possible to filter a suspension or emulsion in a filter bed of particulate filter medium by allowing the suspension to flow upwards through the filter bed simultaneously as the medium flows downwards through a filtering tank wherein filtration takes place. Filtration thus takes place during counterflow between suspension and filter medium. The supply of suspension takes place in the lower part of the filter bed and the filtered liquid phase is taken away from a zone above the filter bed. The polluted filter medium close to the bottom of the filter tank is taken out for conveyance to a washing apparatus above the filter bed and after washing is returned to the upper side of the filter bed. For providing a filter which has a considerably lower construction height for a given and unchanged volume of the filter medium, the washing apparatus is lowered so that its lower part is at a level below the upper surface of the filter bed.

Abstract: An ion exchange resin regeneration apparatus. A nine compartment module has two end anode electrode compartments and a center cathode electrode compartment. These three compartments contain a mixture of cation and anion resin. The two end compartments are lined by cation membranes while the center compartment is lined on both sides by anion membranes. All but two of the remaining compartments are provided with cation or anion exchange resin and opposing cation and anion membranes in an arrangement whereby a resin slurry may be consecutively directed through two of the compartments for processing.

Abstract: A method for the removal of pollutant ions from an aqueous solution in which they are contained, which method includes the steps of:i) contacting the solution to be treated with particles of a composite magnetic resin which includes magnetic particles embedded in an organic polymeric matrix which either contains, or has attached thereto sites which are selective for the pollutant ions in the presence of other ions it is not desired to remove;ii) separating by magnetic filtration the composite magnetic resin particles from the solution;iii) subjecting the separated composite magnetic resin particles to regeneration using an appropriate regenerant solution;iv) separating the regenerated composite magnetic resin particles from the regenerant solution; andv) recycling the separated composite magnetic resin particles to step (i) of the method.

Abstract: Water is purified to reduce pollution to less than 0.3%, by mixing re-generated and non re-generated anion and cation resins, followed by appropriate final mixing of both when re-generated, for further use.

Abstract: A process for the removal of thermally-stable contaminants from stack gas scrubbing amines using a continuous countercurrent ion exchange column. Amines contaminated after use in stack gas scrubbing are fed into the column containing an anion exchanger resin where the contaminants are sorbed on the resin. The amine is washed from the resin with hot water and is removed from the column. The resin is then pulsed to move the resin with the sorbed contaminants into a elution section of the column. The contaminants are removed using an eluant of sodium hydroxide solution, preferably containing chlorine to enhance elution of thiocyanate ion. A water wash removes traces of the hydroxide solution and any reaction products, and then the resin is again pulsed so as to be moved for reuse. The amines are regenerated with only the single type resin (preferably Type I) and with significantly reduced quantity of reagents.

Abstract: The present invention provides a process for treating ion exchange resin which includes the steps of firstly introducing a liquor for treating the resin in substantially vertical upflow into a treatment zone in order to produce a fluidised bed comprising the resin and insoluble particulate matter interspersed with each other, and secondly separating the resin from the particulate matter through entrainment of the latter by the liquor being withdrawn from the fluidised bed in a substantially horizontal flow direction. An apparatus for performing the process outlined above is also disclosed.

Abstract: A process for dewatering an aqueous fluid containing solids using water-absorbent substances is disclosed. A water-absorbent substance and a body to which the solids will adhere are added to the solids-containing aqueous fluid. The water-absorbent substance absorbs water and the solids coat the solids-adhering body. The water-laden substance may then be separated from the solid-adhering body that is coated with solids, thereby separating the water and the solids.

Abstract: A water softening device is provided with a waste storage tank for receiving waste liquid, such as hard water used to draw out brine from a brine storage tank, as well as the used brine itself during a regeneration cycle. The tank outlet communicates with a sprinkler system, and when the sprinkler system is on, an injector valve sucks waste liquid from the waste tank to mix it in with the sprinkler system water and thereby further dilute the liquid. A method of processing the waste water accordingly includes collecting this waste liquid and preferably mixing it in with the sprinkler fluid. The brine waste and brine supply tanks in one embodiment are preferably formed as one unit with two separate compartments. The inlet pipe to the brine waste compartment has an overflow safety valve which senses, through a float mechanism, when the tank is substantially full. The valve has a normally closed port connected to a leach line or the like.

Abstract: A method for regenerating the exhausted anion and cation exchange resin in a mixed bed demineralizer which utilizes an interface tank to increase the volume of interface resin that is physically isolated to increase separation efficiencies. An anticipatory interface detection sample flow of cation resin is directed from an intermediate section of the separation vessel through a sample line into the interface tank simultaneously with the transfer of cation resin from the bottom of the separation vessel into a cation regeneration vessel. Upon detection of an interface by the entry of anion resin, or inert material if present, into the sample line, the transfer of cation resin into the cation regeneration tank is terminated. The remaining cation resin from the separation vessel is transferred into the interface tank until an interface is detected by the entry of anion resin, or inert material if present, into the cation transfer line.

Abstract: A relatively simple and more economical method for regenerating activated carbon wherein at least partially spent activated carbon is fed from a portable container directly to a heating zone without the use of liquid to transport the at least partially spent activated carbon to the heating zone. A portable container for use in the activated carbon regeneration method can be used to hold the activated carbon during adsorption processes, during storage of the activated carbon, and during transportation of the activated carbon between an adsorption site and a regeneration site. In the activated carbon regeneration method, the portable container is preferably positioned adjacent a conveyor so that the spent activated carbon can be delivered directly to the conveyor with an auger. The spent activated carbon is then fed directly to the heating zone with the conveyor.

Abstract: A method for regenerating exhausted anion and cation exchange resins for service in an associated mixed bed demineralizer. The method utilizes a portion of the exhausted anion and cation resins to form buffer zones which reduce cross-contamination between the anion and cation resins during regeneration. Alternatively, a relatively inert material having a specific density intermediate to that of the anion and cation resins can be used to form the buffer zones. The materials which form the buffer zones remain in the regeneration system and are not returned to the service vessels with the regenerated resin. The method includes an improved technique for terminating the transfer of cation resin from a separation vessel.

Abstract: Particles of an ion exchange resin are brought into contact with water in a water circulation system in a power plant for capturing corrosion products and other impurities and are removed after reaction with the corrosion products and the other impurities from the water circulation system, the water circulation system including a reactor vessel or a steam generator connected thereto for generation of steam, a steam turbine driven by the steam, a condenser for condensing the steam from the steam turbine and a condensate cleaning filter for cleaning condensate formed in the condenser, as well as one or more pumps for effecting the water circulation and returning cleaned condensate to the reactor vessel or the steam generator.

Abstract: A method as provided wherein betaine is separated eluted from beet molasses using a chromatographic simulated moving bed system having at least three chromatographic columns connected in series. The betaine is eluted during the same cycle as sucrose and rest molasses feeding and substantially simultaneous water feeding step, at least one water feeding step, a circulation step, and elution of sucrose, betaine and rest molasses fractions from selected columns.

Abstract: A method and apparatus for the continuous treatment of fluid with a contact media. The apparatus includes a plurality of vertically arranged chambers through which the fluid flow passes. The contact media may be selectively removed from each chamber and moved to a tank for regeneration. Additionally, the contact media may be selectively moved from one chamber to another.

Abstract: A method for separating and transferring an ion-exchange resin having the lower specific gravity from an ion-exchange resin having the higher specific gravity in an ion-exchange resin separating tank that is indispensable to a pure or ultrapure water producing plant and which is packed with a mixed bed of ion-exchange resins having different specific gravities is disclosed.

Abstract: This invention pertains to a water-insolubilized resin of a polymer of at least one monomer selected from N-alkyl- or N-alkylene-substituted acrylamides or methacrylamides represented by the following general formula (I): ##STR1## wherein R.sub.1 and R.sub.2 mean individually a hydrogen atom or methyl group and R.sub.3 denotes a methyl, ethyl or propyl group, with the proviso that R.sub.3 is an ethyl or propyl group when R.sub.2 stands for a hydrogen atom, and that R.sub.3 is a methyl or ethyl group when R.sub.2 stands for a methyl group, or wherein R.sub.2 and R.sub.3 form --CH.sub.2).sub.4 or --CH.sub.2).sub.2 O--CH.sub.2).sub.2 in combination; or a copolymer of at least one monomer selected from the acrylamides or methacrylamides and another copolymerizable monomer. The resin has water-absorbing capacity which varies in degree depending on temperature and, when heated, undergoes shrinkage even in the presence of a large excess of water to release once-absorbed water.

Abstract: A process is described involving the detoxification of waste water containing heavy metals which includes recovering the metals in salable form. The metals are removed from the waste water by contacting the water with an ion exchange resin bed contained in a portable canister until it is determined that the resin is saturated with metal. This determination is made by measuring the appearance of heavy metal salts in the effluent from the canister.

Abstract: The invention relates to a method and an arrangement for enabling a contaminated medium to be cleansed in a contact reactor by introducing thereinto a pulverulent absorption material capable of reacting with contaminants in the medium, the medium and the absorption material being mixed together in the contact reactor over a period of time in which contaminants react with the material, therewith to absorb on and react with individual particles in the pulverulent absorption material.

Abstract: A process is described involving the detoxification of waste water containing heavy metals which includes recovering the metals in salable form. The metals are removed from the waste water by contacting the water with an ion exchange resin bed contained in a portable canister until it is determined that the resin is saturated with metal. This determination is made by measuring the appearance of heavy metal salts in the effluent from the canister. Regeneration of the resin and recovery of the metal is accomplished in a location diverse to that where the metal is removed from the waste water by (a) back washing the resin with water into a backwashing receiver (b) forward washing the resin with water (c) forward washing the resin with a regenerating solution (d) collecting the regenerating solution in a plurality of fractions wherein the first fractions contain the majority of the metal recovered and (e) forward washing the resin with water to remove excess regenerating agent.

Abstract: Regenerated adsorbent particles, such as activated carbon, are recovered from a wet oxidation-regenerated mixed liquor sludge from a wastewater treatment system by diluting and settling a blowdown slurry from the wet oxidation reactor to obtain a first aqueous phase containing primarily regenerated adsorbent particles and fine ash particles and a first solids phase containing primarily grit particles. The first aqueous phase is combined with a portion of the regenerated adsorbent particle slurry withdrawn from the upper portion of the wet oxidation reactor and, after treatment with a dispersing agent and then an anionic flocculating agent, the resulting mixture is settled to obtain a second aqueous phase containing primarily fine ash particles and a second solids phase containing primarily regenerated adsorbent particles.

Abstract: A mixed resin bed deionizing apparatus for removing toxic or mineral substances from fluid passing through a loading vessel containing a mixed bed of cation and anion resins and a regeneration assembly for regenerating the cation and anion resins for return to the loading vessel, the assembly including a separation vessel for separating the cation and anion resins and two "U"-shaped regeneration vessels, one for regenerating cation resins and one for regenerating aniona resins, the resins being admitted to the regeneration vessels in predetermined amounts which are advanced through the regeneration vessels by removing a predetermined amounts of regenerated resin from the discharge end of the vessel, shifting the remaining resin in the vessel to refill the space in the discharge end and adding a corresponding amount of exhausted or loaded resin to the other end, passing a regenerant through the regeneration vessel counter to the direction of movement of the resin through the regeneration vessel and rinsing the

Abstract: Method for rendering visible the line of separation between cation exchangers and anion exchangers in mixed-bed filters, in which method an amount of a cation exchanger (anion exchanger) sufficient to form a visible line is added to the cation exchangers and anion exchangers constituting the mixed-bed, the added ion exchanger clearly differing optically from the cation exchanger and anion exchanger used to build up the mixed-bed and having a density 0.01-0.05 g/ml lower (higher) than that of the mixed-bed cation exchanger (mixed-bed anion exchanger), and the resin beads of which predominantly having the same particle sizes as the finest (coarsest) screen fraction of the mixed-bed cation exchanger (mixed-bed anion exchanger).

Abstract: The invention relates to improved methods for regenerating the exhausted anion and cation exchange resins in a mixed bed demineralizer system. The exhausted bed of resin is directed into a separation vessel which contains a buffer volume of anion and cation resins remaining therein from the previous regeneration cycle. The resin in the separation vessel is classified into an upper anion resin layer, a lower cation resin layer and an intermediate layer of intermingled anion and cation resin. The cation resin is transferred from the bottom of the separation vessel to a cation regeneration vessel through a cation transfer conduit having isolation valves associated with the respective ends thereof. The resin transfer is terminated upon the detection of anion resin in the transfer conduit, at which time the isolation valves are closed so as to isolate the bulk of the intermingled anion and cation resin layer in the cation transfer conduit.

Abstract: A method for the treatment of liquids containing particles in suspension, by percolation of the liquid from top to bottom through a bed of granular material, notably of a ion exchanger resin, includes treatment cycles of the liquid and regeneration cycles of the resin, preceded by decompaction and washing operations, carried out in the same enclosure the inner space of which is divided into two superimposed compartments in mutual communication. The lower compartment is totally filled with granular material and the upper compartment is partly filled with granular material. The decompaction and washing operations of the granular material contained in the enclosure upper compartment are carried out periodically prior to each regeneration cycle by expanding the granular material by means of a current of liquid flowing from bottom to top.

Abstract: Upward-flow process for treating liquids in ion exchange filters containing cation exchangers and anion exchangers in separate layers arranged one on top of the other, in which the cation and anion exchangers are separated from one another by a resin layer which does not participate in the ion exchange, the anion exchanger is regenerated externally and the cation exchanger, which remains in the filter, is regenerated in the counter-current and the anion exchanger is removed from and recycled to the filter without whirling up the separating layer and cation exchanger layer. The invention furthermore relates to a new counter-current ion exchange filter for carrying out the process.

Abstract: This invention provides a method and an apparatus for effecting counter-current mass exchange between two non-miscible phases A and B, for example a liquid phase A and a liquid or solid phase B, circulating in opposite directions from one end to an opposite end of a vertical tower comprising a plurality of superposed chambers in which the first phase A is caused to circulate continuously and the second phase B is caused to circulate discontinuously. One chamber is empty and is adapted to receive the phase B contained in the next chamber thereabove, the two chambers being isolated from any supply of phases A and B. A small fraction of the liquid phase A is diverted for directing continuously this phase to the other chambers of the tower, the thus diverted fraction being introduced into the next chamber above the empty chamber for carrying away the phase B contained in the lower empty chamber, this diverted fraction being reintroduced into the circuit.

Abstract: The present invention relates to a method for purifying aqueous solutions or condensate in a three component resin system comprising a mixed bed of a strongly basic anion exchange resin, a strongly acidic cation exchange resin and a weakly acidic cation exchange resin. According to the present method, aqueous solutions can be treated to remove metal ions and corrosion products along with ammonia and other volatile amines so that metal ion leakage is substantially reduced and the run length of the resin system is increased. A method for separating and isolating the resins of the three component system is also described.

Abstract: A mixed bed polishing process for regeneration of an exhausted mixed resin bed of cation exchange and anion exchange resins of different densities comprising the steps of scrubbing with air the exhausted mixed resin bed and adding into the mixed resin bed inert resins having a density intermediate the densities of the cation exchange and anion exchange resins. The exhausted mixed resin bed is backwashed to separate into three layers the cation exchange, anion exchange and inert resins. The anion exchange resins are transferred to an anion regenerator; and then, the inert resins are transferred to an inert resin storage tank. The cation exchange resins are regenerated with acid; and then, the anion exchange resins are regenerated with caustic regenerant. The regenerated cation exchange and regenerated anion exchange resins are separately rinsed, and then, mixed together and rinsed.