AWWA JAW57692

Use of ion exchange to remove arsenic (As) from drinking water has been viewed skeptically by many water suppliers, primarily because the cost of resin regeneration makes the process uneconomical when the system is operated conventionally. Furthermore, the appeal of ion exchange for treating a variety of contaminants is frequently limited by the brine requirements. The novel ion exchange process described here reduces the brine requirements and extends the service life of ion exchange beds used for As removal. By modifying operation of the ion exchange resins, a larger fraction of their capacity can be devoted to removing As. At the same time, the brine management system can be adapted to require much less makeup brine. Results of this study show that the process of ion exchange can be operated more efficiently, making it a viable treatment option for both As and a number of other contaminants. Water suppliers may want to take another look at ion exchange to determine whether the process can meet their treatment objectives at reasonable costs. Includes 17 references, figures.