| Popis: |
The efficiency of radium removal by a home water softener was evaluated in a manually-operated unit that had been in service for about 10 years. The concentrations of calcium, magnesium, and radium in the water provided during a 100-day period averaged 70·2 ± 0·6 mg liter −1 , 24·8 ± 0·6 mg liter −1 , and 0·355 ± 0·007 Bq liter −1 , respectively. The concentration of radium in the effluent remained at 1·3 ± 1·0% of the input level throughout the entire 100-day period. In contrast, the concentration of magnesium began to increase by 30 days. By 40 days, the hardness had increased so much that the homeowner would have initiated another recharge cycle. However, the experiment was allowed to continue until the magnesium content had reached 80% of the influent level. There is no indication that the efficiency of radium removal by this water softener was affected by age or past use. Radium was removed even after the effluent had become hard and a recharge cycle was needed. |
