Boron Removal Calculator Help

Purolite S108 is selective N-glucamine based resin for boron and is largely unimpacted by other ions present in the water being treated. The resin is designed to operate in the slightly acidic to slightly alkaline pH range. It is readily regenerated with dilute sulfuric or hydrochloric acid. Following acid elution, the resin should be converted to the sodium form using a dilute solution of caustic soda. Both co-flow and counter—flow regeneration modes are acceptable in general to achieve boron leakages ranging from about 0.01 to 1 ppm boron. As boron selective resins age, the weak base functionality of the resin tends to hold on longer to the caustic used to convert the resin to sodium form; this can lead to unacceptably long rinse times before the pH of the treated water drops to an acceptable level. For larger plants, especially, we offer the option to add an extra very dilute acid step to partially neutralize residual caustic held by the resin and avoid any extended rinsing that may otherwise be needed. This consists of a backflush step in which ¼ of a bed volume of dilute 0.1% acid is introduced into the bottom of resin column in an up-flow manner at a controlled rate. Please consult Purolite for additional details as needed.
 
Our normal design is to use a lead-lag pair of vessels, otherwise known as a primary and polisher pair of vessels – this design should give the lowest leakage when properly operated. If continuous operation is needed, a third equally sized vessel is placed on stand-by mode until needed. The vessels are then operated in a merry-go-round fashion, with the lead vessel removed for regeneration while the polisher vessel is switched to the primary position (by switching valves) and the regenerated standby vessel is switched into the polishing position. The exhausted resin can then be regenerated and put into stand-by mode for the next cycle. One typical option for operation is to take the primary vessel out of service when the boron breakpoint target is reached in the effluent from the polisher vessel. A more conservative approach would be to operate based on boron breakpoint being reached in the effluent from the primary vessel - this latter option obviously gives greater protection but will shorten service cycle time and result in higher usage of regenerants.
 
If designing with a third vessel in stand-by mode, please remember to add the extra volume of resin needed for that vessel (as it is not currently shown in the calculator).