Nepali Water Solutions Inc.
Group members:Heather Lukacs Luca MorgantiChian Siong Low Barika PooleHannah Sullivan Jeff HwangXuan Gao Tommy Ngai
Point-of-Use Water Treatment in Nepal
Advisors:Susan Murcott, Harry Hemond
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Presentation Outline
1. Project Background2. Project Goals3. Arsenic Removal4. Filtration5. Chlorine Disinfection6. Tubewell Maintenance7. Conclusion
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Project Background
Population 24 million (88% rural)Average annual income: $ 210Pop. below poverty line: 42%Access to safe water: 90% urban, 30% rural
Infant mortality: 75/1000 birth (5/1000 in US)Diarrheal illnesses: 44000 child death/yearLife expectancy: 58
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Project Goals
Main objective:To investigate appropriate technology to provide safe drinking water for rural Nepal population
Criteria:
1. Technical performance2. Social/cultural acceptability3. Economic viable/sustainability
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Introduction
• Arsenic contaminated groundwater discovered in Terai region.
• 4% of 5000 tubewells tested have arsenic contents greater than 50 ppb (18% have greater than 10 ppb).
• Arsenic causes
hyperpigmentation,
skin and liver cancer,
and circulatory disorder.
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Goals
• Evaluate & Test three different household arsenic removal technologies
• Develop a comprehensive map to identify the extent of arsenic contamination within Nepal.
• Water quality analysis to determine factors that affect arsenic presence and removal.
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Evaluation Criteria
• Effectiveness of unit to reduce arsenic concentration below 10 ppb (WHO Standard)
• Appropriateness/Social Acceptability
- Can it be made with local material by local labor?
- Is it easy to operate and maintain?
- Can it meet the water demand (40-50 liters per day per household)?
• Cost
- Is it affordable to average Nepali household?
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Arsenic Removal withActivated Alumina (AA)
• Promising household unit using AA developed by Bangladesh University of Engineering and Technology (BUET)
• Adsorption by AA efficiently removes Arsenic (up to 98 % removal achieved)
• Current cost per unit is $26 ($15 per unit possible with mass production)
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Prototype Design
• Features:
- Oxidation-sedimentation unit
- Sand filtration unit
- AA adsorption column
• Problems with the Current Design:
- Flimsy frame
- Too tall
- Inadequate flow rate
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Arsenic Removal with Iron Coated Sand
• Iron oxide adsorbs arsenic from water• Iron coated sand is more porous and has a higher
specific surface area than scrap iron• Can be regenerated and reused at least 50 times
with out loss in treatment efficiency. • Has been effective in Bangladesh
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System Design
• Sand preparation:
- Fe(NO3)3 is dissolved
- NaOH is added, and iron oxide is formed
- Sand is added to the colloid solution, mixed and baked for 15 hours
• Cost ~ US$ 8
• Flow rate 6 L/h
• 94-99% removal
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Pepperell, MA
• Well water analysis for arsenic contamination conducted 20 years ago
• Sample collection and analysis on Industrial Test System Arsenic Test Kits
• Arsenic still present in Pepperell, MA well water • Confirmation on Graphite Furnace Atomic Absorption
Spectrometer • EPA has lowered the arsenic MCL to 10 ppb, and many
households are over the new limit• We will test our technologies in Pepperell prior to field
tests in Nepal
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How to improve removal?
• Both AA and Iron coated sand work best with As(V) instead of As(III)
• Arsenic speciation in Nepal varies• Oxidation of Arsenic can improve removal
efficiency
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BP/I3 resin
• Benzyl Pyridinium Triiodine• Developed by Aquatic Treatment Systems• 100% oxidation in 1 second• On-demand oxidant• Very stable, no by-products• Some ability to disinfect
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Arsenic map of Nepal
• Based on well info from ENPHO and Nepal Red Cross Society
• Develop a map to show the extent arsenic contamination
• Integrate
information
into GIS format
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To develop arsenic map
• Attend GIS class• Get relevant maps (scale, regions, details)• Get data from ENPHO/Red Cross• Obtain field data• Integrate all data into GIS format• Perform analysis on data• Print a big map
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Water Quality Parameters
• Want to investigate correlations between presence of arsenic and other parameters
• Parameters of interest:
pH, hardness, alkalinity, turbidity, conductivity, arsenic, iron, aluminum, sulfate, chloride, copper,
phosphate, nitrate• Investigate the effects of these parameters on
arsenic removal efficiency by our technologies• Can integrate these data on GIS
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Current Progress
• Accomplishments thus far
- Literature review
- Technology selection
- Contacts made
- Received some supplies and equipment
- Test kit analysis
- Arranged GFAAS analysis
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Next Steps
• Next steps:- Obtain supplies (e.g. buckets, pipes)- Build prototypes- Preliminary lab tests- GFAAS analysis- Field tests in Pepperell
- BP/I3 Resin tests- Water quality analysis- Order digitized maps of Nepal
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Terafil Terracotta Filter
• Mixture of red pottery clay, river sand, wood sawdust
• Designed by Regional Research Laboratory, India
• Field tested in cyclone affected areas in Orissa, India (Oct 1999)
• In-house test verification
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Scope of Work
In MIT,• Carry out lab tests on Terafil Filter and Potters for
Peace Filter (PFP) (ongoing)• Terafil and PFP Literature Review• Compare effectiveness of Terafil and PFP Filter• Research into ceramic manufacturing process and
local practices
MITMassachusetts Institute of Technology
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Scope of Work
In Nepal,• Carry out field tests on Terafil and/or PFP Filter• Get involved with local filter manufacture
Back in MIT,• Wrap up test results into thesis• Possible research into other suitable filters for use
in developing countries
MITMassachusetts Institute of Technology
Nepal
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Work in Progress
• Lab familiarization completed with preliminary testing of Terafil filter
• Devise comprehensive lab tests on filter with specific goals
• Lab tests on PFP and improvised Terafil filter– Pre- and Post-Chlorination (Terafil only)
– Colloidal silver coating (both)
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Laboratory Testing
• Physical parameter– Flowrate, turbidity, temperature
• Chemical parameter– pH
• Microbial parameters– H2S bacteria, Total Coliform/E.Coli (P/A tests)
– Total Bacteria (Microscopic Direct Counts)
– Total Coliform (Coliform Counts)
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Biosand Filter Features
• Slow sand filtration
• Relatively fast flow rate
• Made of local materials
• Intermittent use
• No chemical additives
• Biofilm (Schmutzdecke)
• Easy to clean
• Economically sustainable
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Biosand Filter Performance
• Laboratory Studies– Parasite removal – 100%
– Virus removal – 99.9%
– Bacteria removal – 99.5% (Lee 2001)
• Field Studies– Bacteria removal 60-99.9%
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Biosand Project Goals
• Expand 2001 MIT Biosand work• Slow sand literature review and applicability• Global Biosand usage• Methodology development
– Maintain constant concentration input
• Laboratory study of bacterial removal– After cleaning– Following pause time
• Field study in Nepal– Quantification of fecal coliform removal
(membrane filtration)– Turbidity, pH, Temperature
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Chlorine Disinfection
Investigated Fields
1. Household Chlorination (Hannah Sullivan)
2. Chlorine Generation (Luca Morganti)
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Safe Water System (CDC)
• Point-of-Use Treatment using locally produced and distributed sodium hypochlorite solution.
• Safe Water Storage in plastic containers with narrow mouths, secure lids and dispensing spigots to prevent recontamination.
• Behavior Change Techniques to influence hygiene behaviors and increase awareness about the dangers of contaminated water and waterborne disease.
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Promising Results
• Implemented World-wide– Kenya, Uganda, Zambia, Guatemala, Bolivia,
Ecuador, Peru, Pakistan • Reduces levels of bacterial contamination• Low Cost
– Annual cost of $1.17 - $1.62 per household
Reduces incidence of waterborne disease
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Lumbini Pilot Study
Pilot Study of Household Chlorination
March 2001
• Modeled after CDC’s Safe Water Systems• Experimental Group: 50 Families & 10 Schools• Control Group: 50 Families & 10 Schools
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M.Eng Project
1. Review of CDC’s Safe Water System Program
- History, Types of Programs, Costs, Sustainability
2. Evaluation of Lumbini Pilot Project
- Point-of-Use Testing
- Chlorine Residual,
- Bacterial Analysis (H2S and MF)
- Health Survey
- Social Acceptability Survey
3. Recommendations for Lumbini and Nepal
- Is the Safe Water Systems Approach Appropriate?
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The Problem
Chlorine is not readily available for disinfection
Chlorine disinfectant (Piyush) is produced from imported bleaching powder (calcium chloride)– Dependence
– Limited availability
– Export of money
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The Solution
PRODUCE CHLORINE LOCALLY
• Self-sufficiency• Easier supply• Generation of income for local people
HOW ?
Chlorine Generator (CG)(Nadine Van Zyl, M.Eng.2001)
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Chlorine Generator Specs-1
• Electrolytic cell: NaCl +H2O -> NaClO + H2
• Batch system: easy regulation
Amount/day equivalent Cl2
6.0 Lb 2.7 kg
Salt consumptionper 24 h. cycle
30.0 Lb 13.6 kg
Water consumption per 24 h. cycle
120 Gal 455 L
Specific energy consumption
2.5 kW/Lb 5.5 kW/kg
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Purpose of the study
• Identify performance influencing factors (water and salt quality)
• Define CG set-up procedure• Learn CG use and maintenance procedures• Test CG performance (concentration)• Train local personnel• Outline a micro-enterprise program
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CG Sustainability
• Economically:– Cost of materials, energy, labor– Reasonable price
• Environmentally:– Energy source (solar energy)
• Socially:– Actractive business?– Reliable business ?– Expanding market ?
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Tubewell
• Ground water is the main source in the most of the Terai areas
• Ground water hand pump device
• 5 to 10 households share 1 tube well
• Tubewell water is better than dugwell water or surface water
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Problem with Tubewells
Past study has shown that over 70% of the tube well water in Lumbini is contaminated by bacteria.
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Possible Causes of the Problem
• Poor Sanitary Conditions– Sludge drilling which uses a slurry of cow dung
– Inadequate sealing or protection of the well
– Improper drainage that causes accumulation of wastewater in the pit nearby
– Flooding during monsoon
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Tubewell Maintenance Program
• Determination of the sources of tubewell contamination
• Development of a plan to eliminate the contamination and maintain the wells properly
• A study of the suitability for shock chlorination of wells– One-time introduction of a strong chlorine solution into
a well.
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Progress and Future Work
• Progress– Laboratory Testing at MIT
– Contact with FINNIDA
– Literature Review
• Future work– More literature review
– Pilot study in Butwal, Nepal
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