Kanchan Arsenic Filter (KAF)
Massachusetts Institute of Technology (MIT), Environment and Public Health Organization (ENPHO) of Nepal, Rural Water Supply and Sanitation Support Programme (RWSSSP) of Nepal
An adaptation of the Biosand filter to remove arsenic in addition to turbidity and bacteria.
The Kanchan Arsenic Filter (KAF) is an adaptation of the Biosand Filter that removes arsenic in addition to turbidity and pathogens. The Biosand filter is a household scale slow sand filter. A plastic or concrete casing is filled with layers of graded sand and gravel. A biological layer, which contributes to pathogen removal, forms on the top layer of sand. Water passes through the biological layer and filters through the graded sand and gravel. The KAF incorporates an additional layer of non-galvanized nails in the diffuser basin of the filter. Rust (ferric hydroxide) is formed when the iron nails are exposed to air and water. Arsenic in the water adsorbs to the surface of the ferric hydroxide particles and is filtered out of the water.
Nepal and Bangladesh
About $20 USD (1400 to 1800 NRs). It has been estimated that 90% of users will need subsidized price to afford to purchase a filter (at 0.2-0.5% of of their income).
Other household water treatment methods and technologies available on the local market and other arsenic removal technologies including the ElectroChemical Arsenic Remediation (ECAR) system.
Goal 6: Clean water and sanitation
Individuals and households who rely on arsenic contaminated water for drinking.
