METHOD OF OPERATING WATER SOFTENING APPARATUS HAVING TWO CALIBRATION CHARACTERISTICS AND CORRESPONDING WATER SOFTENING APPARATUS Russian patent published in 2013 - IPC C02F1/42 G05D21/02 B01J49/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of operating a water softening apparatus with an ion exchange device, having an ion exchange resin, a supply vessel for supplying a regenerating solution for regenerating the ion exchange resin, a mixing device, and at least one flow metre, wherein a volume flow V(t)_raw of raw water flowing towards the water softening apparatus (1) is divided into a first partial volume flow and a second partial volume flow upstream of or in the water softening apparatus (1), the first partial volume flow being guided through the ion exchange resin (5) and that softened partial volume flow V(t)_part1soft being mixed with the second, raw water-bearing partial volume flow V(t)_part2soft, whereby in or downstream of the water softening apparatus (1) an effluent volume flow V(t)_mixed of mixed water is formed. Conversion using a first calibration curve (F1) is conservative and reflects the maximum water hardness occurring at different conductivity values; this is used to automatically control the regeneration of an ion exchange resin (5) for known capacity of the ion exchange resin. Conversion using a second calibration curve (F2) is close to reality and reflects the average water hardness (i.e., hardness subject to the least statistical errors) at different conductivity values; this is used to control the mixing device (i.e. the ratios of the two partial volume flows in the mixed water). The invention also relates to a water softening apparatus with an ion exchange device.

EFFECT: detecting differences in composition of water in order to determine the optimal point in time of regeneration and minimise tolerances concerning the hardness of mixed water against a set value.

13 cl, 3 dwg