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Poster made for the Legatum Seed Grant final presentation of my Nepal thesis and project work.
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y = 0.0057x -‐ 1.0882 R² = 0.4228
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Ferrou
s Iron A+
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e Nails (m
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Hardness in the Groundwater (mg/L)
y = -‐0.4358x + 64.893 R² = 0.0076
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r Arsen
ic (μ
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Groundwater Chloride (mg/L)
y = -‐37.155x + 91.234 R² = 0.085
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Ferrous Iron a+er the Nails (mg/L)
y = 0.3662x -‐ 18.268 R² = 0.1869
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Groundwater Arsenic (μg/L)
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Arsenic Co
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g/L)
Filter Referance Number Ground water Filter Outlet
KanchanTM Arsenic Filter Nawalparasi, Nepal
Project Description: The Kanchan Arsenic FilterTM (KAF) was developed by the Department of Civil and Environmental Engineering at MIT in collaboration with the Environmental and Public Health Organization (ENPHO, Nepal) for the low-cost removal of arsenic from drinking water in Nepal. Groundwater arsenic contamination is a recognized problem in many areas of South Asia. However, the uncertain performance of the KAF under various water quality conditions has limited the distribution of the KAF outside of Nepal. Our study focused on assessing the effect of various groundwater chemical parameters on the arsenic removal performance of the KAF.
Tested Parameters: Findings: The KAF will not perform well in groundwater conditions that do not promote iron corrosion.
Poor Performance Indicators: • GW As > 200 ug/L • Nail Fe(II) < 1.1 mg/L • GW Chloride < 7 mg/L
Next Steps: Incorporating local components into the KAF system to increase iron corrosion (i.e. rock salt - NaCl) so that it can be promoted in areas with various groundwater conditions.
Providing safe & affordable water to rural communities
Claudia M Espinoza & Maclyn O’Donnell
• pH • Dissolved Oxygen • Chloride • Electrical Conductivity • Manganese
• Arsenic • Ferrous Iron • Phosphate • Silica/Silicate • Hardness (CaCO3)
• Flow Rate • Filter Age • Location • User Survey
• low GW Hardness • high GW pH
Test Results:
• Tested 101 filtered water and 77 groundwater samples in 15 different villages.
• Phosphate, Silica, Dissolved Oxygen, Manganese, Conductivity, Flow, Age, and Location did not affect KAF Performance
Figure 2: As in the GW vs. FW. Error: +/-20% (As ≤100 µg/L) and +/-50 µg/L (As >100 µg/L).
Figure 1: Overview of measured As. Error: +/-20% (As ≤100 µg/L) and +/- 50 µg/L (As >100 µg/L).
Figure 3: Fe(II) after nails vs. As in FW. Error: +/-20% (As ≤100 µg/L), +/-50 µg/L (As >100 µg/L), +/-0.03 mg/L (Fe ≤1 mg/L), and +/-20% (Fe >1mg/L).
Figure 4: GW Cl vs. As in FW. Error: +/-20% (As ≤100 µg/L), +/-50 µg/L (As >100 µg/L), and +/-10% (Cl). Figure 5: GW hardness vs. Fe(II) after nails. Error: +/-0.03 mg/
L (Fe ≤1 mg/L), +/-20% (Fe >1mg/L) and +/-10% (hardness).
red solid line - Nepali arsenic drinking water standard (50 µg/L)
green dotted line - Shift from mostly well performing KAFs to both well and poor performing KAFs
GW = groundwater
FW = filtered water
Kathmandu Valley
Sampling Methodology: Arsenic Overview:
