Onsite defluoridation system for drinking water treatment using calcium carbonate

Area of Science:

• Environmental Science
• Water Chemistry
• Materials Science

Background:

• Excess fluoride in drinking water poses significant risks to dental and skeletal health.
• High fluoride levels are prevalent in many regions globally, necessitating accessible treatment solutions.
• Existing advanced defluoridation methods are often too costly for developing areas.

Purpose of the Study:

• To investigate calcium carbonate as a cost-effective sorbent for on-site fluoride removal from drinking water.
• To evaluate the efficiency of calcium carbonate in defluoridation systems suitable for household use.
• To develop a simple, maintainable water treatment alternative for communities with limited resources.

Main Methods:

• Batch and column experiments were conducted to assess fluoride (F-) removal.
• Fluoride sorption was characterized using the Freundlich isotherm model.
• Comparative analysis was performed against commercial ion exchange resins, eggshells, and seashells.

Main Results:

• Calcium carbonate demonstrated comparable fluoride removal to commercial ion exchange resins.
• It exhibited higher removal effectiveness than eggshells and seashells.
• Chloride ions (Cl-) did not significantly interfere with fluoride removal at typical concentrations.
• Equilibrium time for fluoride sorption was approximately 3 hours.

Conclusions:

• Calcium carbonate is a viable, cost-effective material for on-site fluoride removal.
• The proposed system is user-friendly and maintainable for household application.
• This research contributes to providing safe drinking water access in fluoride-affected regions.