Abstract
The removal of excess sulfate from brackish water was carried out using a weak anion exchanger that was regenerated with a potassium chloride solution. The potassium sulfate was removed from the regeneration solution by adding solid KCl, which reduces the solubility of K2SO4. Dilution of the regenerated solution was substantially reduced by using three displacement solutions with different KCl concentrations. Precipitation of potassium sulfate in the column during regeneration was prevented by heating it to 50–60°C. After the regeneration solution exited the column, it was cooled to achieve maximal precipitation of the K2SO4. The weight of the K2SO4 obtained was about the same as that of the KCl used for regeneration. The volume of the solution disposed to drain approached zero.
Acknowledgments
This research was partly supported by Dead Sea Works Ltd.