A process is described for treating water, in particular for obtaining ultrapure water, in which a decationized water stream is passed at least through a first strong base anion exchange bed and a second strong base anion exchange bed, which is arranged downstream, in particular directly downstream, of the first strong base anion exchange bed. Furthermore, a water treatment system and a counter-current ion exchange unit for carrying out such a process are described.

A process is described for treating water, in particular for obtaining ultrapure water, in which a decationized water stream is passed at least through a first strong base anion exchange bed and a second strong base anion exchange bed, which is arranged downstream, in particular directly downstream, of the first strong base anion exchange bed. Furthermore, a water treatment system and a counter-current ion exchange unit for carrying out such a process are described.

A sensor for detecting the breakthrough of hardness in a water softener measures a change in the conductivity of elongated cation-exchange material in contact with the treated water.

A method for converting a salt-based ion exchange water softener into a brine-based system. The system includes a resin tank containing an ion exchange media, a batch tank containing crystalline salt, a master valve for directing water flow through selected portions of the softener system, a brine conduit connecting the batch tank to the master valve, and a controller for managing the master valve position to define at least operating, brine fill, and brine draw cycles. A control valve is installed in the brine conduit to prevent fresh water flow from the master valve to the batch tank and the crystalline salt in the batch tank replaced with a quantity of liquid brine. It is preferable to adjust the duration of the brine draw cycle to limit the brine draw cycle to the minimum time necessary to provide sufficient brine to the resin tank to recharge the ion exchange media.

A method for fluid treatment that provides variable or alternative regeneration cycles within the same fluid treatment device. The duration of all stages of the regeneration cycle can be adjusted depending upon the amount of fluid treated so that regenerant resources such as water are not underutilized and waste is not discharged unnecessarily into the environment. Additionally or alternatively, a regeneration sequence may include a fluid release sequence in which a fluid is released from a water treatment tank by successive linear movement of a piston in a valve assembly.

A method for fluid treatment that provides variable or alternative regeneration cycles within the same fluid treatment device. The duration of all stages of the regeneration cycle can be adjusted depending upon the amount of fluid treated so that regenerant resources such as water are not underutilized and waste is not discharged unnecessarily into the environment. Additionally or alternatively, a regeneration sequence may include a fluid release sequence in which a fluid is released from a water treatment tank by successive linear movement of a piston in a valve assembly.

A control valve (10) includes a valve body with a plurality of ports (A, B, C, D, E, F) and a plurality of annular flow passages (53, 55,57). A piston (34) which includes a plurality of annular flow passages and a longitudinal flow passage is selectively movable within a bore (32) within the valve body through operation of a valve controller (70). The valve controller is selectively operative to control the position of the piston so as to enable liquid flow through a plurality of flow paths. A master controller wirelessly communicates with a plurality of slave controllers, including the valve controller. The master controller is operative to control conditions of the valve and an associated liquid treatment tank.

A control valve (10) includes a valve body with a plurality of ports (A, B, C, D, E, F) and a plurality of annular flow passages (53, 55,57). A piston (34) which includes a plurality of annular flow passages and a longitudinal flow passage is selectively movable within a bore (32) within the valve body through operation of a valve controller (70). The valve controller is selectively operative to control the position of the piston so as to enable liquid flow through a plurality of flow paths. A master controller wirelessly communicates with a plurality of slave controllers, including the valve controller. The master controller is operative to control conditions of the valve and an associated liquid treatment tank.

A control valve (10) includes a valve body with a plurality of ports (A, B, C, D, E, F) and a plurality of annular flow passages (53, 55, 57). A piston (34) which includes a plurality of annular flow passages and a longitudinal flow passage is selectively movable within a bore (32) within the valve body through operation of a valve controller (70). The valve controller is selectively operative to control the position of the piston so as to enable liquid flow through a plurality of flow paths. The valve controller further includes a installable and removable valve controller housing (74) which is releasibly engageable with a valve base (72). The valve may include a changeable multi-piece piston and changeable injector and plug components to adapt the valve to different flow and fluid mixing requirements.

A water softener regeneration system for a water softener configured to soften and filter water, the regeneration system includes a water hardness measurement system configured to determine a hardness value of water flowing out of the water softener. A brine tank is in communication with the water softener and operable to regenerate the water softener with brine from the brine tank. A controller is operable to control the brine tank, wherein the controller actuates by one of opening and closing the brine tank based on the hardness value which is indicative of the effectiveness of the water softener.