Water softening device and method for regeneration control thereof

A water softening apparatus comprising a plurality of water softening devices disposed and connected in parallel with water flowing operation and regenerating operation of each water softening device switchable, the water softening apparatus, being composed of inlet hardness measurement means for measuring hardness of feedwater to a water softening apparatus, treated water quantity measurement means for measuring a flow rate of treated water after passing through the water softening apparatus, brine concentration detection means for detecting concentration of brine in regenerating operation, and brine consumption detection means for detecting consumption of brine in regenerating operation;

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• a control means connected to said means for measuring hardness, means for measuring flow rate, brine concentration detection means and brine consumption detection means for controlling a regeneration commencing time by determining a setting value of a hardness removal amount available based on outputs from said brine concentration detection means and said brine consumption detection means and comparing the setting value to an integrated value of hardness removal amount based on outputs from said hardness measuring means and treated water quality measurement means.