Fluorine or nitrate nitrogen (NO3, NO2) contained in water can be removed with strongly alkaline anion exchanger of an R ¡Õ NCl type.
Even when removing fluorine only, nitrate nitrogen should be removed at the same time in case where nitrate nitrogen actually exists in raw water.
Nitrate nitrogen is difficult to regenerating, thus regeneration level should be 200 g NaCl/§¤ - R or more. If regeneration is performed with a low regeneration level in order to remove fluorine only, nitrate nitrogen is not removed thus accumulating nitrate nitrogen and deteriorating the fluorine removing competence.
Therefore, the case of fluorine removal and the case of nitrate nitrogen removal should be regarded the same.