Water softener regeneration monitoring process and assembly maximizes use of the regeneration agents and minimizes the use of water

摘要

In a process to operate a water softener, the unit is regenerated from time to time using in-situ measurements of the residual hardness using an ion-selective sensor. A minimum flow of process water is tapped from the softener through a valve to the sensor. A sensor process signal varies the rate at which process water is tapped from the ion-exchange section at the same time as the process water flows through the softener. The ion-selective sensor continually monitors the ion concentration in the tapped flow. Water softener regeneration is initiated if the ion concentration exceeds a certain pre-determined level. During periods when the process is inoperative, the tapped flow is interrupted, and a calibration fluid is fed to the sensor via the valve.