Arsenic Filter
Long-term exposure to arsenic from drinking-water can cause cancer and skin lesions. As this prevalent problem could not be addressed by filters available in the market, IDC designed a household filter using indigenous materials. For user convenience, Iron nails which can be easily washed and replaced are used as the source of iron for reaction and a simple gravel filter to filter the precipitates. The filter containers are perforated water storage drums, manufactured locally. The low maintenance arsenic filters can filter water with arsenic levels up to 300 ppb achieving WHO’s provisional guideline value of 10 ppb.
Long-term exposure to arsenic from drinking-water can cause cancer and skin lesions. As this prevalent problem could not be addressed by filters available in the market, a household filter was designed using indigenous materials.
- Simple assembly process.
- Easy to clean and maintain.
- No regular replacement of components required.
- Compact, lightweight, and portable, making it convenient during floods or for cleaning purposes.
- Can be manufactured locally.
- Affordable and cost-effective. Operates without the need for power.
Arsenic Filter has the following salient features:
- IIT Bombay Arsenic removal filter uses only locally available materials and is fabricated by local plumbers and masons.
- The process achieves oxidation of As(III) to As(V) & subsequent arsenic removal by hydrous ferric oxide, which is formed from oxidation of leached Fe2+, without the addition of any chemicals.
- The unit is cost-effective and robust, does not require extensive monitoring.
- Designed operational Fe/As ratio is 15 which has taken into consideration phosphate presence and also factor of safety of 3. This is much lower than all other reported systems.
- This low Fe/As ratio makes the unit simple to operate and require less maintenance.
- Twenty times less sludge is generated, as compared to current technologies, due to efficient utilization of iron as seen from low Fe/As ratio.
- The unit has a simple design which enables local persons to replicate it wherever required.
- IIT Bombay Arsenic filter provides drinking water to meet the daily needs of 200-300 families.
- IIT Bombay Arsenic filter is able to achieve arsenic level of <10μg/L for initial arsenic concentrations of up to 750 μg/L (tested at field, more than 2000 μg/L tested in lab) at a flowrate of 600-1000 L/h.
- The cost for producing 1 cubic metre of water (average monthly requirement for a family of 5 persons) varies from Rs. 0.10 to Rs. 1.00 (inclusive of maintenance of handpump, iron replenishment and filter washing labour cost).
Arsenic filter consists of the following units:
- Inlet pipe
- Iron contactor
- Gravel filter
- Cleaning ports
- Collection pipe
The following are the health impacts reported by the IITB Arsenic filter users (based on qualitative surveys):
- Improved health and reduced medical bills
- Indigestion and gastric problems reduced within a week
- The arsenic lesions are seen to reduce within a year with regular use of the IITB Arsenic filter water
- Visible markings on the skin and discolouration of teeth was also reduced
- Greater energy throughout the day to do more work and children are more playful and play the games with more vigour
- People become more polite and patient and this leads to less fights among people of the community
- Hunger is increased i.e. the people are able to eat and digest more
- Some blood pressure tests carried out by local medical personnel showed a marked reduction in the blood pressure of the elderly and an overall normalization in blood pressure of the people in the village
Healthcare, Water Treatment and Purification, Household Water Safety Solutions, Sustainable Development and Rural Technology.