Abstract: A method and apparatus for selecting the quantity of salt to be used during each regeneration of a water softener system. The quantity of salt used during each regeneration is approximately equal to the quantity of salt needed to regenerate the resin bed to a preselected design capacity, which is less than the maximum capacity of the resin bed. The design exchange capacity is approximately equal to the exchange capacity of the resin bed at a particular salt dosage, wherein the exchange capacity of the bed at the particular salt dosage divided by the particular salt dosage is generally equal to or greater than 2850. The system is regenerated when at the end of any preselected time period, the percentage of the design capacity of the resin bed used since the last regeneration cycle exceeds a predetermined percentage.In determining the salt dosage used during each regeneration cycle, the exchange capacity of the resin bed is determined for various salt dosages.

Abstract: Ability of ion adsorption apparatus such as a desalting unit, etc. as used in an atomic power plant is continuously monitored, and any deterioration in the ability is detected in advance by a method and an apparatus for monitoring a break in an ion adsorption apparatus by detecting a break point of the ion adsorption apparatus using ion exchange resin, thereby determining a timing for regenerating or exchanging the resin, which comprises making an ion species having a weaker selective adsortability to the ion exchange resin as a sampling ion species than that of a target ion species to be adsorbed and present in water to be treated, and detecting leakage of the sampling ion species at the downstream side of the adsorption apparatus, thereby determining the break point of the ion exchange resin.

Abstract: A process and system are provided for treating fluid. In one illustrative embodiment, the treatment comprises the recharging of a resin bed in a water softener. A flow switch and accumulating timer are actuated when a selected flow rate is detected. The accumulating timer is set to a selected elapsed time. A chronological timer is also provided and is set for a selected time of day to recharge the resin bed. A reserve brine capacity is provided by delivering a selected amount of water to a brine tank at predetermined elapsed time intervals of the accumulating timer. The resin bed is recharged when both a selected elapsed time of the accumulating timer has occurred and it is the selected time of day.

Abstract: A system for producing deionized water comprising at least a pair of oppositely charged ion exchanger units connected in series, a pump, a sensor for detecting the level of specific conductivity of process water and lines connecting the pump, ion exchanger unit and sensor in a closed-loop flow circuit. A controller operates the system in a first mode in which a batch of process water is repeatedly circulated along the closed-loop flow circuit until the specific conductivity sensed is less than a first predetermined level and alternately in a second mode in which the batch of water so treated is discharged while another batch of water is introduced into the system until the specific conductivity sensed is greater than a second predetermined level which is higher than the first predetermined level.

Abstract: A water treatment system includes a water treatment tank containing a resin bed through which water is passed for treatment thereof during normal operation of the treatment system. A brine tank contains a brine solution which, when passed through the resin bed, results in regeneration of the treatment effectiveness of the bed. A plurality of electrically actuatable valve means direct water through the treatment tank during normal operation of the treatment system and direct brine solution through the treatment tank in a regeneration operation. A control for the water treatment system includes means for manually entering control data, display means for displaying data, and sensor means for sensing the volume of water treated by the water treatment system. A controller circuit means is responsive to means for manually entering control data and to the sensor means and is connected to display data on the display means.

Abstract: A process is provided for controlling the recharging of a water conditioner. Water usage during selected fractions of a predetermined period of time is sensed. Information signifying the water usage during the selected fractions is stored. A time fraction is automatically determined, based on the stored information, when water is unlikely to be used. A selected parameter, such as volume of water used since recharging, is sensed to determine if recharging is required. The water conditioner is recharged during the automatically determined time fraction if the selected parameter indicates that recharging is required.

Abstract: An improved method for producing ion-selective membranes having a desired shape and of a desired plastic, for incorporation in ion-sensing electrodes, and the electrodes incorporating these membranes. This method allows the use of preformed polymeric members having the desired shape to produce ion-selective membranes, allowing simplified production of ion-sensing electrodes, as well as combination ion-sensing and reference electrodes.

Abstract: A water purifier for treating water intended for drinking and like purposes, for installation at point-of-use, i.e., home, office or workplace, which is effective in removing additional contaminents therefrom using a heated carbon filter and distillation, in which the water being purified is heated and induced to alternately flow back and forth between an open compartment used for the filter and a closed evaporator in which it is distilled, the intervals of flow into the filter compartment being effective to heat the filter to thereby increase its ability to remove heavy molecular pollutants (e.g., pesticides, herbicides, etc.) and also being an advantageous location from which there is released to atmosphere low molecular volatile pollutants (e.g.

Abstract: An on-line and continuous sampling system for monitoring the ionic content of steam-producing water in a steam-operated electrical power plant. The monitoring system comprises a plurality of sampling lines and associated apparatus for sampling the steam-producing water at a number of different points in the power plant, an ion chromatographic subsystem for analyzing the sampled water, a calibration subsystem for calibrating the ion chromatographic subsystem, and an automatic control subsystem for operating the monitoring system of the present invention.

Abstract: An improved control for a particle bed water treatment device includes a microcomputer which is supplied with input data from a flowmeter indicative of the quantity of treated water leaving the water treatment device. In accordance with the flow data, the microcomputer determines the amount of water used since the last regeneration and also determines the average daily treated water consumption. The microcomputer is also coupled to a data input device and receives input data indicative of the total particle bed treating capacity resulting in complete particle bed exhaustion. To recognize and account for the additional particle bed capacity that is created when a partially exhausted particle bed is regenerated, the microcomputer advantageously adjusts the total treating bed capacity value received from the data input device in accordance with the remaining particle capacity existing prior to regeneration.

Abstract: An improved control for a water softener includes a resin bed sensor for sensing when the resin bed has been depleted to a predetermined percentage of the total resin bed treating capacity. The resin bed sensor is connected to a microcomputer which is also coupled to a flow meter to receive data therefrom indicative of the quantity of treated water leaving the water treatment device over a given period of time. When the resin bed sensor signals the microcomputer that the resin bed has been depleted to the predetermined capacity the microcomputer calculates the total softening capacity of the resin bed. Each day, the microcomputer computes both the total quantity of treated water consumed since the last regeneration and the remaining capacity of the resin bed. The microcomputer also maintains a record in memory of the previous 7 days' usage and the average usage is calculated to establish a soft water reserve value.

Abstract: A high degree of water purity is obtained from a mixed-bed deionization process by minimization of cross-contamination of the cation and anion materials. After service, the materials are classified into superimposed uppermost, intermediate and lowermost layers above a perforate barrier in a separator vessel. The vessel has an elongate conduit having an inlet adjacent the barrier and an outlet outside the vessel. At least a major proportion of the material of the lowermost layer is passed through the outlet of the conduit and an interface between materials is detected. Thereupon, the conduit outlet is isolated from the conduit inlet so as to segregate in the conduit material from the intermediate layer. The ion exchange materials are then regenerated and re-mixed. The segregated material is independently removed from the conduit before the next regeneration cycle starts.

Abstract: A process for removing dissolved aluminum and silica contaminants from concentrated alkali metal halide brines used in membrane electrolytic cells is disclosed. The process involves contacting an acidified brine at a pH of between about 2.0 and about 3.0 with a strong macroreticular cationic chelating resin.

Abstract: In a method of regenerating mixed ion exchange materials, the materials are classified into layers. The lower layer is then transferred from the separator vessel. The transfer is controlled by detecting an interface between materials. The separated materials are then regenerated after which the anion material is reclassified to allow any contaminant cation material to settle to the bottom thereof. Material is then removed from the bottom of the anion layer to remove settled contaminant cation material. The removed material is isolated from the regenerated materials which are then remixed.The method reduces the cross-contamination of materials that occurs during the separation of classified materials and, particularly, reduces the amount of cation material in the sodium form (following regeneration of the anion material) that is eventually returned to service.

Abstract: A cooling arrangement particularly for cooling electrical devices having water cooled electric conductors with deionized cooling water in a closed cooling system which contains a parallel loop with a mixed bed filter in which an anion exchanger in OH form is provided which can be connected parallel with the mixed bed filter as well as in series with the mixed bed filter, permitting the cooling system to be run with the cooling water having an increased pH-value range which can be preferably 8 to 8.4.

Abstract: A detergent-containing radioactive liquid waste originating from atomic power plants is concentrated to have about 10 wt. % detergent concentration, then dried in a thin film evaporator, and converted into powder. Powdered activated carbon is added to the radioactive waste in advance to prevent the liquid waste from foaming in the evaporator by the action of surface active agents contained in the detergent. The activated carbon is added in accordance with the COD concentration of the radioactive liquid waste to be treated, and usually at a concentration 2-4 times as large as the COD concentration of the liquid waste to be treated. A powdery product having a moisture content of not more than 15 wt. % is obtained from the evaporator, and pelletized and then packed into drums to be stored for a predetermined period.

Abstract: The invention relates to a cooling arrangement, particularly for cooling electrical devices with water-cooled electric conductors, with deionized cooling water (deionate) and a closed cooling system which contains a parallel loop with a mixed-bed filter. According to the invention, the mixed-bed filter is preceded by an alkalizing cation exchanger and an anion exchanger in OH-form, and the mixed-bed filter is provided with a bypass. With this arrangement, the cooling water can be run in a higher pH-value range which for generators may preferentially be about 8 to 8.4.

Abstract: A deionization method and apparatus comprising separate cation and anion removing sections 10a, 10b, the cation section having separate tanks 14, 16 and the anion section having separate tanks 24, 26. Respective cation and anion control valve assemblies 18, 28 control the fluid communication between various components of respective sections and control the regeneration cycle of exhausted cation and anion tanks, respectively. Each valve assembly includes independent water usage monitoring devices 118 which, upon sensing a predetermined quantity of water discharge by its respective valve assembly, effects regeneration of an associated tank. An exhausted cation tank is regenerated by feeding cation regeneration fluid by way of the cation control valve assembly into the exhausted cation tank in a counterflow direction for a predetermined time. Decationized water from the on-line cation tank is then passed through the exhausted cation tank in a counterflow direction to effect a counterflow rinse.

Abstract: An improved control for a resin bed water softener includes a microcomputer which is supplied with input data from a flowmeter indicative of the quantity of soft water leaving the softener. In accordance with the flow data, the microcomputer determines the amount of water used since the last regeneration and also determines the average daily soft water consumption. The microcomputer also coupled to a data input device and receives input data indicative of the total resin bed treating capacity and the incoming water hardness. At a prescribed hour each day, the microcomputer determines the remaining water softener resin bed treating capacity as calculated from the water hardness, the total resin bed treating capacity and the amount of water used since the last regeneration.

Abstract: A simulated moving bed process divides the bed into separate zones, each of which includes one or more discrete vessels. The zones correspond to the functions of the process; typically sorption, displacement, elution and regeneration. Booster pumps in series with the vessels maintain a desired pressure head for each zone. The functions of each zone are rotated in sequence, the sequence being timed in relation to the migration of the front between adjacent phases in the fluid loop circulating through the zones.

Abstract: A method of analyzing a sample solution containing an ionic species of interest paired with an ionic species of the opposite sign comprises introducing the sample solution into a separation column with an eluant solution, introducing an eluate from the separation column into the inner passage of a diffusion type deionizer of the double tubular construction which is defined by a tube of an ion exchange composition, while a scavenger solution is introduced into the outer passage of the deionizer in a direction of flow opposite to that of the eluate in the inner passage, whereby the ionic species of the opposite sign is removed from the eluate into the scavenger solution, and measuring the electric conductivity of the eluate from the deionizer to thereby determine the concentration of the ionic species of interest in the sample solution. An apparatus for carrying out this method is also disclosed.

Abstract: A water softener control includes a cell of sampling resin which received periodic samples of water which has passed through a major portion of the softening bed. The sampling resin changes volume when it becomes exhausted and the change in volume is employed to initiate regeneration of the softening bed. At the start of the regeneration cycle, regenerative fluid is delivered directly to the sampling resin as well as to the softening bed. The delivery to the sampling resin is through a control valve which is piloted by pressures at a venturi injector which is used to withdraw regenerative fluid from a brine tank. A vacuum operated control valve which is responsive to the closing of an air check valve in the connection between the injector and the brine tank may be employed to positively close the connection from the sampling cell to the injector when the supply of regenerative fluid is exhausted.

Abstract: A water treatment system includes a water treatment tank containing a resin bed through which water is passed for treatment thereof during normal operation of the treatment system. A brine tank contains a brine solution which, when passed through the resin bed, results in regeneration of the treatment effectiveness of the bed. A plurality of electrically actuatable valve means direct water through the treatment tank during normal operation of the treatment system and direct brine solution through the treatment tank in a regeneration operation. A control for the water treatment system includes means for manually entering control data, display means for displaying data, and sensor means for sensing the volume of water treated by the water treatment system. A controller circuit means is responsive to means for manually entering control data and to the sensor means and is connected to display data on the display means.

Abstract: Treatment of water for selective and quantitative removal of all cations of the transition elements, with simultaneous adjustment of a definite mole ratio of calcium, magnesium, and the alkali metals, with a cation exchanger which, towards the ions of the I. transition elements, II. alkaline earth metals, III. alkali metals, shows a markedly gradually decreasing affinity from I. to III.; and which cation exchanger is loaded with calcium and magnesium ions in a predetermined mole ratio, or with hydrogen or sodium ions to obtain a water corresponding to the desired type of water in a vessel made of a water-resistant material and having at least one water-permeable wall.

Abstract: In mixed bed ion exchange resin regeneration processes, transfer of resin after classification is controlled by detecting a change in a parameter of transfer water dependent on ion concentration, e.g. conductivity. The process includes increasing the ion concentration of the transfer water. The increased ion concentration ensures that large percentage uncontrolled fluctuations in the conductivity of the water do not mask the change required to be detected. The ion concentration can be increased by adding, for example, decationized water to the transfer water.

Abstract: A method and apparatus for visually monitoring the fluidized bed of a resin ion exchanger. The method includes establishing a sample fluidized bed displaced from, but in fluid communication with, the resin ion exchanger fluidized bed and supplying a quantity of exchanger process solution in a controlled manner to the sample fluidized bed such that the sample fluidized bed represents among other exchanger fluidized bed characteristics the exchanger fluidized bed height. The apparatus includes a monitor having a transparent sampling column in fluid communication with the exchanger fluidized bed and a regulator in fluid communication with the exchanger and the sample column for establishing a solution sample for supply to the sample fluidized bed. The regulator includes an orifice for controlling the flow rate of solution sample supplied to the sample fluidized bed.

Abstract: Ion exchange medium in a water softening system is regenerated cyclically, in response to both a preset timer and a metering device responsive to the degree of hardness of the untreated water and the degree of exhaustion of the ion exchange medium, by slowly feeding regenerating medium, prepared during the softening phase by the metering device, counter current to flow during softening at a rate so as not to disturb the exchange medium and to prevent substantial mixing of the regenerating medium with the water being displaced.

Abstract: A method for determining the concentration of a specific ion in a solution which involves dividing the solution to be analyzed into two portions. One portion is treated with an ion exchange resin with the other portion being treted with a reagent, e.g., a precipitating agent in order to remove the desired ion from solution, and at least one ion exchange resin. The reagent and ion exchange resin can be one and the same. The two streams are then passed into opposite sides of a detection cell comprising two ion specific electrodes connected through conventional bridge circuitry. The concentration of the desired ion is determined from the difference in electrical potential between the two ion specific electrodes. Instead of dividing the stream and then treating the reference portion it is also possible to treat the entire stream first to replace all ions changed oppositely to the desired ions and then divide the streams.

Abstract: In an automated process for deaerating and purifying both the water which is recirculated in a coolant loop through a stack of fuel cells and the make-up water for the coolant loop, a portion of the water from the coolant loop is blown down into a deaerator water reservoir to which make-up water is added by condensing water from the fuel cell stack reactant gas streams into a deaeration column disposed above the reservoir. The blowdown provides some of the heat for deaeration; and the amount of blowdown is controlled as a function of the amount of make-up water added to the coolant loop by sensing the location of a steam/liquid interface within the deaeration column. Water is withdrawn from the reservoir, purified, and then introduced into the coolant loop at a rate sufficient to maintain the desired amount of water circulating in the coolant loop.

Abstract: Apparatus is described for the removal and recovery of pollutant oil and the like floating on the surface of a body of water, comprising: means capable of the physical withdrawal of pollutant oil and the like with or without additional water from the water surface to a recovery station on site; means for spraying hot water over such pollutant oil and the like at said recovery station; a receiving tank for the oil/water washings resulting; an oil/water separator/coalescer for separating oil containing a minor quantity of water only from the washings; means for receiving such separated oil; means for recirculating water from said separator/coalescer for heating and further spraying; and means for returning any excess purified water from said separator/coalescer to said body of water.

Abstract: Process for treating wastewater, which includes measuring the pH of the wastewater, adjusting the pH to about 10-11; filtering the wastewater; and subjecting the wastewater to ion-exchange treatment; and certain filter media.

Abstract: Chromate ions present in aqueous solutions, e.g. cooling tower blowdown water or liquors obtained from the electrolysis of aqueous sodium chloride solutions, are substantially completely removed by passing the solution through an intimate mixture of an anion exchange resin in the chloride form and a weak cation exchange resin in a conditioned hydrogen form.

Abstract: A method of regenerating etchant and recovering etched metals. Etching solution, which is overladen with metal cations is passed through a cation exchange unit. Subsequently, the etching solution, which is diminished in metal cation concentration, is returned to the etcher sump. The cation exchange unit is then rinsed with deionized water to remove residual etching solution, with the effluent being conveyed to a metal recovery unit. The cation exchange unit is then rinsed with an aqueous solution of an acid to remove cations and to regenerate the cation exchange unit. The effluent from this rinsing is also conveyed to the metal recovery unit. The cation exchange unit is then rinsed with deionized water to remove residual acid, with this effluent likewise being conveyed to the metal recovery unit. Subsequently, a selectolyte solution is passed through the cation exchange unit to enhance the cation retention property thereof. The effluent is conveyed to a storage container.

Abstract: A method and apparatus for initiating the regeneration cycle of an ion exchange resin type water softener based upon the movement of the "hardness front" through the resin bed as water being treated is passed therethrough. Electrical probes are provided at predetermined longitudinally spaced locations and the difference in potential between the probes is measured, as is the rate of change of this potential with respect to time. It is found that as the hardness front passes between the probes, a detectable change in potential occurs which may be applied to an electronic circuit for generating a control signal which may initiate the regeneration cycle of the water softener subsequent to the arrival of the hardness front in the zone between the probes.

Abstract: Apparatus and method for chromatographic separation and quantitation of different ions of like charges in a sample, e.g., cations or anions. Referring to anion separation, the sample is directed to a first chromatographic column of the ion exclusion type in which the weak acids (e.g., carboxylic acids) and their salts are partially or totally resolved and separated from a fraction of strong acids (e.g., mineral acids) due to Donnan exclusion. The resolved weak acids may be passed directly to a conductivity cell for quantitative detection. The strong acids may be directed to anion exchange bed with a highly ionized developing reagent and eluted in resolved form with the effluent being passed to a suppressor ion exchange bed wherein the developing reagent is converted to a weakly ionized form without destroying the anion separation. Then, a fraction of the strong acids is detected with the same or a different conductivity cell.

Abstract: At least part of the effluent from an ion exchanger flows past a first and second electrode. The electrodes are mounted within the pipe carrying the fluid so that they are visible from the outside. A DC voltage is applied between the electrodes. If the effluent contains a metal which should have been adsorbed by the ion exchanger, its presence is indicated either by a change in the voltage-current curve of the electrodes or a change in color of the cathode. Either a single metal or a group of metals may be precipitated.

Abstract: A method is provided for selectively separating and removing complexed heavy metal ions, preferably copper or nickel, from complexing agents in aqueous solution and removing substantially all heavy metal ions while leaving complexing agent in said solution. In preferred embodiments, complexed copper or complexed nickel is selectively removed from aqueous effluent from electroless plating systems by passage through a bed of chelating ion-exchange resin having an iminodiacetic acid functionality. Substantially all copper or nickel will be removed from solution and retained in the resin bed and the complexing agent will pass through for conventional waste treatment or disposal. The copper or nickel is recovered by elution from the resin bed with an acid solution and may, if desired, be precipitated by addition of sodium hydroxide or the like and subsequently separated for recovery or disposal.

Abstract: Water containing traces of oil is cleaned by passing the oil containing water through a foraminous body, the foraminous body having a coating on the surface thereof of an oil-imbibing, oil-swellable latex polymer in a quantity sufficient to blind the foraminous body when the latex is oil swollen.

Abstract: A high degree of water purity is obtained from a mixed-bed deionization process by minimization of cross-contamination of the cation and anion materials. After service, the materials are classified into superimposed uppermost, intermediate and lowermost layers above a perforate barrier in a separator vessel. The vessel has an elongate conduit having an inlet adjacent the barrier and an outlet outside the vessel. At least a major proportion of the material of the lowermost layer is passed through the outlet of the conduit and an interface between materials is detected. Thereupon, the conduit outlet is isolated from the conduit inlet so as to segregate in the conduit material from the intermediate layer. The ion exchange materials are then regenerated and re-mixed. The segregated material is independently removed from the conduit before the next regeneration cycle starts.

Abstract: Analytical method based on converting an acid or base species to water or absorbing the acid species whereby the species of interest is no longer responsive to a detector. Interfering salt(s) is simultaneously converted to a detectable acid or hydroxide derivative(s) in whole or in part. The species of interest is determined indirectly by subtracting the response of the salt derivative (which is proportional to the original salt) from a pre-derivatization response which is proportional to the salt plus base or salt plus acid.

Abstract: A process and apparatus for cleaning contaminated raw water, in which raw water and a flocculator are introduced into the reaction space of a pressure vessel, which vessel has such reaction space at the bottom thereof, a filter space above the reaction space and containing a filter made of particles of elastic, granular material, and a clean water space above the filter space so that the raw water passes through the three spaces, whereby the pollution material contained in the raw water becomes enclosed by the cells of the floccules of the flocculator and the floccules become absorbed by the filter particles. Accumulated pollution material is removed from the filter particles by regenerating the filter with a fluid flowing from the clean water space through the filter space into the reaction space. The required extent of purity is achieved by varying the velocity of the raw water introduced into the reaction space, to thereby adjust the percentage of the voids in the filter.

Abstract: The present invention consists of apparatus for purifying water in a continuous manner which removes suspended, dissolved and organic matter and provides water with a neutral pH and having a minimum electrical resistance of 18 Meg ohms for applications requiring ultra-pure water for research and commercial applications.

Abstract: Apparatus for purification of waste water includes an upright adsorber filled with active carbon passing in downward direction through the adsorber while waste water flows in upward direction therethrough. A distributing arrangement is produced at the region of the lower end of the adsorber, into which waste water is fed, and constructed to assure a substantial even distribution of the waste water during its upward flow through the carbon column. A regulating arrangement is provided to regulate the flow of the carbon through the adsorber in dependence on the concentration of the organic contaminants adsorbed by the carbon.

Abstract: An electronic control initiates and controls the regeneration sequence in a resin-type ion exchange apparatus of the type requiring periodic resin regeneration. The electronic control controls the regeneration steps of backwashing, brining and rinsing when respective predetermined fluid flow volumes stored in a memory means pass through the resin. The regeneration sequence may be initiated when a further predetermined fluid flow volume also stored in the memory means passes through the resin. A fluid hardness sensor measures the concentration of objectionable ions for selecting the most advantageous fluid flow volume between regeneration sequences. A brine conductivity sensor determines when the concentration of the regeneration agent falls below the concentration required for adequate regeneration of the resin. An outlet conductivity sensor enables discard or reprocessing of outlet fluid below a predetermined quality. A warning/service alert signals problems or failures in the ion exchange apparatus.

Abstract: An apparatus for purification of waste water includes an upright adsorber filled with inorganic granular adsorption material flowing in downward direction through the adsorber while waste water is fed in upward direction therethrough. The adsorber has a frustoconical outlet portion in which an inlet cone, having a perforated upwardly tapering wall, is provided into which the waste water is fed to assure a substantially even distribution of the waste water in the column of granular adsorption material during the upward flow of the waste water through the adsorber.

Abstract: A mixture of anion and cation exchange resins is separated into their respective resin types by classifying the resin mixture, using a fluid such as water, in the presence of a solid, inert material (e.g., copolymer beads of styrene, divinylbenzene and methyl methacrylate) which, upon classification, forms a layer intermediate between the layers of the anion and cation resins. The degree of resin separation and the location of the layers of the classified anion resin and cation resin are determined by measuring a conductivity property of the resulting classified resin bed.

Abstract: An adsorption process for the selective removal of naphthalenic hydrocarbons in the waste water from a petrochemical operation which comprises contacting the effluent waste water for relatively short periods with activated carbon which has become saturated with respect to non-naphthalenic organics. Contact of the waste water streams with the saturated carbon is continued until the breakthrough of naphthalenic compounds in the waste water exceeds a predetermined concentration, such as 2 ppm. It has been found that efficient removal of naphthalenic compounds can be effected by contacting the waste water for relatively short contact times, for example 10 minutes, notwithstanding the fact that the activated carbon has previously become saturated with respect to non-naphthalenic compounds.

Abstract: Apparatus of high sensitivity and accuracy for detecting and measuring very low levels of chlorides, sulfates, phosphates and nitrates in high pressure, high temperature feedwater present in once-through and supercritical boilers, nuclear reactors and cogeneration systems. A sample of feedwater at 350.degree. F. and above is maintained near atmospheric boiling point in a vented chamber where volatile gases, mainly carbon dioxide, are removed by venting. The effluent from this chamber passes through a flow-type conductivity cell, is cooled to 20.degree.-40.degree. C. and flows upward through a hydrogen exchange resin bed at a flow rate of approximately 250 and 1,000 ml/min and higher. Subsequent reboiling of the condensate in a reboil chamber with the help of a small orifice valve through which a part of the hot feedwater sample passes provides constant temperature control of the condensate at or near atmospheric boiling and at a constant level prior to flow through another flow-type conductivity cell.

Abstract: Measurement is made of low levels of chloride, sulfate, phosphate, nitrate and other inorganic anions in a relatively low pressure condensate having a temperature preferably below 40.degree. C. The condensate is passed through a hydrogen exchange resin bed and the effluent from the resin bed is heated to atmospheric boiling temperature to eliminate gases such as carbon dioxide and ammonia. Heat to maintain a constant atmospheric boiling temperature is supplied by an electric heating element. A temperature sensor on the influent test water adjusts the voltage or current supplied to the electric heating element to maintain the constant atmospheric boiling temperature. A fail-safe device prevents electric heater failure on water flow stoppage. The conductivity of the heated water at or very close to atmospheric boiling point temperature is measured and is an indication of the contamination present in the relatively low pressure, low temperature test condensate.

Abstract: A closed water recycling system produces potable drinking water from total domestic waste-water, including household sewage. The system includes filtration and demineralization units. An electronic controller, which is preferably a microprocessor, monitors the operation of the system and automatically cleans the filter assembly, operates the demineralizer when the monitored variables indicate this is necessary, acts as a failsafe monitor to insure water quality, and shuts down the system in case of a malfunction. For example, the demineralizer may include acid and base regenerated resin beds in an ion-exchange system. When a monitor indicates that the beds require regeneration, acid and base regenerating solutions are supplied to the beds. The flow of regenerating solution and rinse is controlled by the electronics which sense conditions at the bed outlet.