POSTTREATMENT OF DRINKING WATER AND SWIMMING WATER STERILIZED WITH CHLORINE DIOXIDE

摘要

PROBLEM TO BE SOLVED: To completely remove chlorine dioxide remaining in the water which is sterilized by chlorine dioxide, by using a column, filter or filter bed containing water-insoluble iron sulfide ore and/or natural magnesium hydroxide to reduce and remove the chlorine dioxide. SOLUTION: Granular iron sulfide ore such as pyrrhotite is used to pack a column or formed into a filter or added to a filtering bed. Alternatively, natural magnesium hydroxide as a water-insoluble magnesium hydroxide fiber is used to pack a column, formed into a filter or added to a filtering bed. Magnesium hydroxide has an effect to remove chlorine dioxide remaining in water, perchloric acid or oxidizing material by the reducing effect of bivalent iron in the magnesium hydroxide. The column diameter and the treating amt. can be determined according to the concentration of oxidizing material such as the remaining chlorine dioxide, treating time of water. By this method, water can be surely treated and continuous feeding of water is possible for a long time.