Comparative Evaluation of Coconut Shell and Rice Husk as Capping Material in Sand Filter

ABSTRACT: This study evaluates the performance of a rapid sand filtration system enhanced with sustainable, biodegradable capping materials—coconut shell and activated rice husk—to treat water from three sources: tap water, Rakhi Lake, and Nagardhan Lake. Performance was assessed based on Total Dissolved Solids (TDS), pH, turbidity, conductivity, and total hardness. Post-filtration results demonstrated significant improvements across all parameters. TDS levels for tap and Nagardhan Lake water were reduced to the acceptable range of 300–500 ppm. pH levels consistently neutralized within the 6.5–7.5 range. Turbidity was successfully lowered to safe levels (0–10 NTU) for all lake samples. While conductivity decreased across all sources, Nagardhan Lake achieved the standard 200–800 µS/cm range. Furthermore, total hardness was effectively reduced, transitioning all samples from "hard" to "moderately hard" (below 200 mg/L). The findings confirm that utilizing coconut shell and activated rice husk as capping media significantly enhances purification efficiency. This research underscores the practical and environmental benefits of integrating agricultural byproducts into water treatment, offering a low-cost, eco-friendly solution for improving water quality in diverse settings.