Abstract: A water treatment system for removing hard ions from source water. The water treatment system is of the type that includes a pair of ion-exchange water softener tanks connectable to a source of pressurized water and with a water system to supply softened water to the water system, the tanks each being capable of regeneration by flushing with a regeneration solution to replenish depleted ions. A process for preventing system failure due to salt crystallization includes flowing water during brine replenishment from a second nozzle and a first nozzle at a defined ratio. The first nozzle diluted the brine in a reservoir after regeneration cycle is complete. The second nozzle replenishes brine by flowing water directly onto a salt material.

Abstract: Apparatus and method for controlling the resistivity of water. The apparatus includes a diffuser injector for mixing water and a water soluble gas such as carbon dioxide gas and that defines an inlet conduit through which water to be treated is communicated and an output conduit from which treated water is discharged. A diffuser tube is disposed within one of the conduits for injecting carbon dioxide gas into the water. A proportional control valve provides carbon dioxide gas from a carbon dioxide tank to the carbon dioxide diffuser tube. Downstream from the diffuser injector are a static mixer for further intermingling the water and carbon dioxide gas and a serially connected contact chamber for enhancing the stability in the resistivity level of the water. A resistivity monitor measures the resistivity of the water and carbon dioxide mixture and transmits a signal to a controller.

Abstract: A water treatment system including a pair of water treatment tanks, each tank defining a flow path extending from a tank inlet to a tank outlet and containing a water treatment material disposed along the flow path for treating water as it travels from the inlet to the outlet. A system controller controls which of the tanks is on-line and which of the tanks is off-line and controls the regeneration of an exhausted tank. The system controller is operative to provide a final rinse in the service direction. This is accomplished by a purge valve which communicates the outlet of a tank being regenerated to a drain under predetermined operating conditions. The operation of the purge valve is responsive to fluid signals applied to an inlet valve and an outlet valve associated with the tank being regenerated. More specifically, the fluid signals that close the outlet valve and open the inlet valve, are utilized to cause the opening of the purge valve in order to communicate the tank outlet with the drain.

Abstract: A method of filtering feed liquid including a photoresist substance comprises removing cations from the feed liquid using an ion exchange material. A fine particle filter filters the feed liquid and, in particular, removes dissolved solids from the feed liquid. The material is regenerated with a solution, e.g., a brine solution, which has a pH effective to avoid fouling of at least one of the filter and the ion exchange material. Another embodiment concerns a filtration apparatus including an ion exchange device containing the ion exchange material. A fine particle filtration device removes dissolved solids from the liquid. A device for regenerating the material includes a supply of the regenerating solution.

Abstract: A filter for removing particles from a feed liquid. The filter includes a filtration material having a metal oxide composition selected to provide the material with an affinity for the particles of the feed liquid. The affinity of the material is dependent upon a pH of the feed liquid.

Abstract: A tank coupler for releasably interconnecting serially connected tanks. The tank coupler includes threaded engagement portions which are threadedly engageable with ports formed in the tanks. The coupler defines a central fluid passage which receives in a sealing relationship, a riser tube associated with a first tank and a riser tube associated with a second tank. A snap fit mechanism maintains the engagement of one riser tube with the fluid passage in order to control separation of the riser tube from the coupler when the tanks are separated. O-ring seals mounted in grooves forming part of the fluid passage sealingly engage the periphery of the riser tubes and inhibit fluid leakage between the riser tubes and the coupler. The tank coupler also defines a second fluid passage which cross-communicates the interiors of the tanks. Distributors mounted on opposite ends of the second fluid passage inhibit material from moving from one tank to the other while permitting fluid flow.

Abstract: A control valve for a water treatment system which includes a turbine rotatably mounted within a water receiving chamber. A pair of nozzles communicate water from a water receiving chamber to the turbine in a driving relationship. The nozzles each define a passage, preferably converging slightly in cross-section and defining centerlines that converge and intersect at a region swept by the turbine. Preferably, the intersection of the centerlines occurs intermediate a circle defined by central regions of the turbine blades and a circle defined by peripheral edges of the turbine blades. At least one of the nozzles is slidably held in a slot formed in a dividing wall forming part of the control valve and is replaceable by a plug. A confronting surface defines a uniform gap between an outlet side of the nozzles and a peripheral portion of the turbine.

Abstract: A water treatment apparatus and method for softening "problem water". The apparatus includes a pair of treatment tank assemblies, each tank including serially connected filter and ion exchange beds. When a tank assembly requires regeneration, the tank assembly is taken off line and is regenerated using a regenerating apparatus that communicates a mixture of citric acid and brine solution to the ion exchange bed, followed by brine solution alone to form a barrier. A mixture of sodium carbonate and brine solution is then communicated to the ion exchange bed followed by a backwashing step which conveys treated water through both the ion exchange bed and the filter media in a counter flow direction. The regeneration apparatus includes a brine venturi and a chemical draw venturi connected in a parallel flow relationship and solenoid control valves for selectively communicating either a citric acid reservoir or a sodium carbonate reservoir to the chemical draw venturi.

Abstract: A water treatment system including a plurality of treatment tanks containing a water treatment material and defining a fluid flow path through the material extending between a first tank port and a second tank port. A first remotely controlled three way valve associated with the first tank port controls the fluid communication of a source manifold and a regeneration discharge manifold with the first tank port of each tank. A second, remotely controlled three way valve controls the fluid communication of a product receiving manifold and a regeneration chemistry supply manifold with the second port of each tank. A regeneration control monitors the loading of each tank and initiates regeneration in a given tank when that tank reaches a predetermined exhaustion level.

Abstract: A method and apparatus for controlling a fluid treatment apparatus that includes a resin tank containing an ion exchange media. A control valve controls the regeneration cycle and includes a regeneration control turbine operatively connected to a regeneration control disk forming part of a servo system. During regeneration, a meter flow of fluid emitted by a regeneration control nozzle produces rotation in the turbine to effect a regeneration sequence. Regeneration is initiated by a regeneration initiating nozzle which emits a stream of fluid at the turbine for a predetermined time interval in order to initiate a regeneration cycle. A control system includes a sensor for monitoring the fluid quality level of the source fluid or the treated fluid and initiates regeneration. When the control system is used with the disclosed control valve, the control system communicates presssurized fluid to the regeneration initiating nozzle upon sensing a predetermined quality level.