Evaluation of Ion Exchange Performance in Reducing TDS and Water Hardness at Various Regenerant Concentrations
Keywords:
Ion Exchange, TDS, Hardness, RegenerantAbstract
Ion exchange is a water treatment method used to reduce dissolved ions and hardness-causing ions through ion exchange mechanisms on resin surfaces. This practice-based study aimed to evaluate the effect of regenerant concentration on the reduction of total dissolved solids (TDS) and water hardness using an ion exchange resin column. The experiment began with flow rate calibration based on valve opening variations. The main experiment was conducted at a valve opening of 50° with a flow rate of 25.00 mL/s for 90 minutes using regenerant concentrations of 2%, 4%, and 6%. The results showed that the 2% regenerant concentration provided the most stable performance, reducing TDS from 50.15 ppm to 29.80 ppm and hardness from 8.21 ppm to 3.20 ppm as CaCO₃. The final removal efficiencies were 40.58% and 60.98%, respectively. These findings indicate that increasing regenerant concentration does not always improve ion exchange effectiveness under the laboratory operating conditions.
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