Community-Scale Slow Sand Filter (Biochar-Amended Variant)¶
BioSand & Media Filters • Est. CapEx: Low-cost / Locally fabricated
Technical Overview¶
A gravity-driven water purification system that percolates raw water downward through a fine sand bed at low flow rates (0.1–0.4 m/h) to produce potable water without chemicals or electricity. Designed for community-scale and rural deployment—particularly in developing regions lacking centralized infrastructure—it can be enhanced with biochar amendments to boost removal of emerging chemical pollutants.
Key Specifications & Engineering Parameters¶
| Parameter | Specification |
|---|---|
| Category | BioSand & Media Filters |
| Capital Cost | Low-cost / Locally fabricated |
| Primary Mechanism | Water passes through graded layers of gravel and fine sand (effective size 0.15–0.35 mm). A gelatinous biological layer called the schmutzdecke forms on the sand surface after a 1–3 week maturation period, where microorganisms degrade organic matter and pathogens. Physical straining, sedimentation, and adsorption remove turbidity and particulates, while recent biochar amendments add adsorptive capacity for certain dissolved organic contaminants. |
| Target Scale | Household / Village Cluster |
| Standard Lifespan | 10 - 20 Years |
Cross-Reference & Interactive Tools¶
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