LITERATURE IRON ARSENIC FLUORIDE FILTER

NOTE: COPY RIGHTS : TO AVOID COPYRIGHT VIOLATIONS, ALL POSTS ARE SHOWN ALONG WITH SOURCES FROM WHERE ITS TAKEN.PLS CONTACT ME IN MY EMAIL SALEEMASRAF@GMAIL.COM , IF YOU ARE THE AUTHOR AND YOUR NAME IS NOT DISPLAYED IN THE ARTICLE.THE UNINTENTIONAL LAPSE ON MY PART WILL BE IMMIDIATELY CORRECTED.I have collected Articles i found interesting here so that i can read them at my leisure and they can be a good source of information the public. 

Saleem,

Thank you for responding. I am seeking out low cost fluoride removal as well but have yet to come up with something satisfactory. In my case I am looking for P.O.S.(point of entry) or an in-line filtration system of which R.O. is not desirable for cost and other reasons mentioned below. I am looking to filter my bathing water hence the reason for temperature related questions.

I have heard and read that red clay is being used to remove fluoride which may be a low-cost alternative to alumina, charcoal and reverse osmosis. You may already be aware of these trial technologies...http://209.85.173.132/search?q=cache:FPOVywA1ccAJ:www.thinkcycle.org/tc-filesystem/download/development_by_design_2002/publication:_terafil_water_filter_for_sustainable_drinking_water_programme/Terafil%2520Water%2520Filter-final%2520paper.doc+red+clay+removes+fluoride&cd=7&hl=en&ct=clnk&gl=us

http://wedc.lboro.ac.uk/conferences/pdfs/20/Padmasir.pdf (sorry, i don't know why the pictures and illustrations are not shown)

Reverse osmosis does indeed remove fluoride and arsenic but I have come to learn that it is not an idyllic solution. R.O. removes all minerals good or bad indiscriminately and reverses the molecular spin of the molecule creating what is called "aggressive" water. While it will not poison you with a contaminant, true, when consumed for longer than 6 months this water will create mineral deficiency leading to sickness and decreased/suppressed cognitive ability and immune system function. When water is forced through the R.O. membrane the smaller lighter molecules tend to get caught behind the membrane and only the larger heavier molecules get forced through. But from a biological stand point it is the smaller lighter molecules that are of the most health benefit to the body. Additionally the plastic membranes used in R.O. systems are made from a type of plastic that leaches toxins into the water. This is why a post filter of carbon or carbon/kdf is always used.

I deeply sympathize with India and many other country's plight to remove fluoride and other contaminants from the water. How ironic that here in the U.S. fluoride and arsenic are being ADDED to our water at a cost to tax payers and a profit for nuclear, coal and phosphate fertilizer industries.

Best of luck to you,
Mary

USA

On Tue, Mar 17, 2009 at 11:55 PM, saleem asraf syed imdaadullah <saleemasraf@gmail.com>wrote:

Dear Madam,

Fluoride removal by activated alumina is beig done on a wide scale across India, But no follow up study is done to find out the result by any agencies in India. So, adsorption in temperatures much higher than 80 degrees F is to be eshtablished yet. Fluoride and Arsenic removal are two very typical problems I have faced personally. Both can be fully removed by Reverse Osmosis , but because of prohibitive installation cost no body is going for it. And using chemicals and resins are not foolproof. If you have some other suggestions, we can apply them.

Comparison of Main Arsenic Removal Technologies Technology Advantages Disadvantages

http://siteresources.worldbank.org/INTSAREGTOPWATRES/Resources/ArsenicVolII_PaperIII.pdf


 The most commonly used media for arsenic removal in small treatment plants include: • Activated alumina

Arsenic removal by activated alumina is controlled by the pH and arsenic content of water. Arsenic removal is optimum in the narrow pH range from 5.5 to 6.0 when the surface is positively charged. The efficiency drops as the point of zero charge is approached and at pH 8.2, where the surface is negatively charged, the removal capacities are only 2–5% of the capacity at optimal pH (Clifford 1999). The number of bed volumes that can be treated at optimum pH before breakthrough is dependent on the influent arsenic concentration. The bed volume can be estimated using the following equation, where As is the initial arsenic concentration in water in micrograms per liter (Ghurye, Clifford, and Tripp 1999): Bed volume = 210,000 (As)-0.57 The actual bed volume is much lower due to the presence of other competing ions in natural water. Arsenic removal capacities of activated alumina have been reported to vary from 1 mg g-1 to 4 mg g-1 (Fox 1989; Gupta and Chen 1978). Clifford (1999) reported the selectivity of activated alumina as: OH-1>H2 AsO4 -1>Si(OH)3 O-1>HSeO3 -1>F>SO4 -2>CrO4 -2>>HCO3 -1>Cl-1>NO3 -1>Br-1>I-1 Regeneration of saturated alumina is carried out by exposing the medium to 4% caustic soda (NaOH), either in batch or by flow through the column resulting in high-arsenic-contaminated caustic waste water. The residual caustic soda is then washed out and the medium is neutralized with a 2% solution of sulfuric acid rinse. During the process about 5–10% of the alumina is lost and the capacity of the regenerated medium is reduced by 30–40%. The activated alumina needs replacement after 3–4 regenerations. As with the coagulation process, prechlorination improves the column capacity dramatically. The activated alumina-based sorptive media used in Bangladesh and India include: • BUET activated alumina • Alcan enhanced activated alumina • Apyron arsenic treatment unit • Oxide (India) Pvt. Ltd. • RPM Marketing Pvt. Ltd. Arsenic is removed by sorptive filtration through activated alumina. Some units use pretreatment (for example oxidation, sand filtration) to increase efficiency. The Alcan enhanced activated alumina arrangement is shown attached to a tubewell in figure 6 (see page 178). The unit is simple and robust in design. No chemicals are added during treatment and the process wholly relies on the active surface of the media for adsorption of arsenic from water. Other ions present in natural water, such as iron and phosphate, may compete for active sites on alumina and reduce the arsenic removal capacity of the unit. Iron present in shallow tubewell water at elevated levels will eventually accumulate in an activated alumina bed and interfere with flow of water through the bed. The unit can produce more than 3,600 liters of arsenic-safe drinking water per day for 100 families. Apyron Technologies Inc. (United States of America) has developed an

Table 3. Comparison of Costs of Different Arsenic Treatment Technologies in India Technology Treatment process Type Capacity Cost (US$) (manufacturer)

 AMAL (Oxide Adsorption by activated Household 7,000–8,000 L 50 India Catalyst alumina Community 1,500,000 L/cycle 1,250; 400/charge Pvt. Ltd., WB) RPM Marketing Activated alumina + Community 200,000/cycle 1,200; 500/charge Pvt. Ltd. AAFS-50 (patented) All India Institute Oxidation followed Household 30 L/d 5 of Hygiene & by coprecipitation- Community 12,000 L/d 1,000 Public Health filtration Public Health Adsorption on red Community 600–1,000 L/h 1,000 Engineering hematite, sand, and Department, India activated alumina Pal Trockner Ltd., Adsorption by ferric Household 20 L/d 8 India hydroxide Community 900,000 L/cycle 2,000; 625/charge Chemicon & Adsorption by ferric Community 2,000,000 L/cycle 4,500; 400/charge Associates oxide Ion Exchange Adsorption by ion Community 30,000 L/cycle 2,000

FLOW CHART :

Pond/well---Pump---Iron Filter----Activated Alumina Filters---Activated Carbon Filter----UV Tube disinfection----Collection Tank----Supply by 20 Ltr JAR

DESCRIPTION OF PARTS OF THE SYSTEM :

The Iron filter with iron removal media is very high efficiency in Iron, turbidity and bacterial removal.


The Activated Alumina Filter removes both Arsenic and Fluoride. This is a WHO approved conventional method applied all over the world..

The Activated Carbon filter removes residual colour ,odour and Iron. Also it removes the bad effects of activated alumina.

UV Tube disinfects the water before supply.

Source of Water : Pond, Well
To provide 10 liters per capita per day (LPCD) of safe drinking water for drinking and cooking purposes in areas affected by fluoride, arsenic, heavy metals and pesticides. 

Quantity: 3000 Liter per day (For 300 persons @10 liter per person per day ).

Project Cost: .Equipment cost will be around Rs. Three Lac only. Building and other infrastructure cost extra.

To design a system we need

1. The total quantity of water to be treated

2. A water test is recommended.

FOR A SINGLE HOUSE:  FRP Vessel Filter with Arsenic fluoride media .Cost:Rs.2,40,000/=

LOW COST CANDLE FILTER FOR HOME WITH MEDIA FOR IRON ,FLUORIDE & ARSENIC (IFA)REMOVAL     

                      

 

sr no	Item	Specification
1	Filter Body	Three Chamber of 20 Liter each
2	Candle Filter(Tripura Type)	01
3	Plastic Tap	25/=
4	Media	3kg Alumina, 1 kg Carbon(replace after six month
5	Stand	MS, 1 No

Bangladesh  Arsenic problem , health effect: and mitigation

http://www.who.int/bulletin/volumes/90/11/11-101253/en/

Chronic arsenic exposure is linked to a range of dose-dependent conditions, including cancers of the skin, bladder, kidney and lung,^12–14 as well as skin lesions, arterial hypertension and cardiovascular disease, pulmonary disease, peripheral vascular disease, diabetes mellitus and neuropathy

Three known arsenic-related causes of death – cancer, cardiovascular problems, infection – at an exposure level of 10–50 µg/L. On the basis of Sohel’s cause-specific mortality HRs, about 1 in 16 cancer deaths, 1 in 36 cardiovascular disease deaths and 1 in 19 deaths from infections are attributable to arsenic exposure

Mitigation strategy

Provide water treatment in clusters of 100,200,300 people.

For provision of safe drinking-water:

·         Deeper wells (more than 150 meter) are often less likely to be contaminated.

·         Rain water harvesting in areas of high rainfall such as in Bangladesh. Care must be taken that collection systems are adequate and do not present risk of infection or provide breeding sites for mosquitoes.

·         Use of arsenic removal systems in households (generally for shorter periods) and before water distribution in piped systems.

·         Testing of water for levels of arsenic and informing users.

In order to effectively promote the health of people the following issues should be taken into account:

·         Monitoring by health workers - people need to be checked for early signs of arsenicosis - usually skin problems in areas where arsenic in known to occur.

·         Health education regarding harmful effects of arsenicosis and how to avoid them.

References

·         Arsenic, Fact sheet n°372

Prepared for World Water Day 2001. Reviewed by staff and experts from the Programme for Promotion of Chemical Safety (PCS), and the Water, Sanitation and Health unit (WSH), World Health Organization (WHO), Geneva

WHO/WSH/WWD/DFS.13

http://www.who.int/water_sanitation_health/diseases/arsenicosis/en/

Source of Article :http://www.assamtribune.com/scripts/detailsnew.asp?id=jan2916/at056

Arsenic and fluoride Contamination in Groundwater  rising in Assam

Ajit Patowary
 GUWAHATI, Jan 28 - Cases of contamination of groundwater in the State are swelling up everyday, making groundwater unsafe for consumption. According to the official data, the number of the State’s districts which have got their groundwater contaminated by fluoride and arsenic has shot up to 22 and 21 respectively from 19 and 20 respectively in 2014-’15.
According to the data available with this newspaper, in 2014-’15, the arsenic affected districts of the State included Baksa, Barpeta, Bongaigaon, Cachar, Darrang, Dhemaji, Dhubri, Goalpara, Hailakandi, Jorhat, Kamrup, Karimganj, Kokrajhar, Lakhimpur, Morigaon, Nagaon, Nalbari, Sivasagar and Sonitpur.
This year, Tinsukia has also been found to be affected by arsenic, raising the number of affected districts to 21, said the sources.
Till 2013-’14, nine districts – Barpeta, Dhubri, Goalpara, Golaghat, Jorhat, Kamrup, Karbi Anglong, Karimganj and Nagaon – were found to be affected by fluoride.
But in 2014-’15, with the inclusion of Baksa, Cachar, Chirang, Darrang, Dibrugarh, Morigaon, Nalbari, Sivasagar, Sonitpur and Udalguri, the number of affected districts rose to 19.
In 2015-’16, with the inclusion of Bongaigaon, Lakhimpur and Tinsukia, the number of fluoride-affected districts have shot up to 22, sources said.
According to experts here, the trend of rise in the number of fluoride and arsenic affected districts should be studied, together with the impact of such contamination of groundwater, which is used by the people of many areas in these districts for the purpose of drinking as well as domestic use, on human and animal health.
Except in the two districts of Karbi Anglong and Nagaon, no comprehensive health impact studies of groundwater contamination in the rest of the districts has so far been known to have been conducted, said the experts. The origin of fluoride so far is known to be geogenic.

The State’s Department of Mining and Mineral may undertake such studies, involving also the Public Health Engineering Department (PHED), Council of Scientific and Industrial Research (CSIR), Central Ground Water Board (CGWB) and the North Eastern Regional Institute of Water and Land Management (NERIWALM) in this regard, said the experts.

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Source Of The Article ::http://www.aviva.ca/article.asp?articleid=131

Water Purification and Treatment Technologies

A comprehensive look at the different methods of filtering and purifying drinking water.

The drinking water treatment technologies used in the majority of systems include one or more of the following methods or media types:

• Sediment Filters - Ranging from 1 to 20 microns are normally used as a prefilter to protect and extend the life of other filters.
• Activated Carbon, including Granulated Activated (GAC), Carbon Block, and Catalytic Carbon – Standalone, or combined with other technologies to remove chlorine, chloramines, VOCs, MTBE, and a wide range of contaminants including lead and mercury.
• Water Softeners – Used to soften "hard" water using ion exchange technology that exchanges magnesium and calcium with sodium or potassium.  Water softeners are not designed to purify water that is microbioligically unsafe.
• BASF ATS Media  – Home systems, usually combined with activated carbon.
• Steam Distillation – Systems for home, business and commercial use.
• Reverse Osmosis (RO) - Systems for home, business and commercial use.
• Deionization – Not recommended for drinking water.
• Ozonation – Nature’s natural sterilizer.
• KDF Media – Advanced zinc-copper alloy with the widest range of contaminant removal.  Usually combined with Granulated Activated Carbon.
• Ceramic – Alternative to germicidal UV-C for filtration of bacteria, etc.
• Activated Alumina – Specifically designed to remove fluoride and arsenic by adsorption.
• Bone Char – The best material for removing fluoride. Bone Char also removes chlorine, heavy metals and radioactive isotopes. For this reason, it is placed after a chlorine adsorption filter in all OPUS systems, to ensure maximum efficiency for adsorbing fluoride.
• Ultraviolet Germicidal Irradiation (UV-C) - To disinfect microbioligically unsafe water.
• Ultra-Filtration (UF) - Ultra Filtration uses membrane technology to reject contaminants from 0.01 to 0.2 microns. UF is effective in the removal of bacteria, pyrogens, high molecular weight dissolved solids and other water contaminants without removing healthful minerals.
• Bioceramic Water Amplification (BCWA) –Technically not a filter, BCWA improves the health promoting qualities of water by increasing alkalinity, oxygen, active hydrogen ions and healthful minerals, while lowering the ORP (Oxidation Reduction Potential), giving water antioxidant properties. BCWA is available as an inline filter that can be added to an existing water treatment system, integrated into a drinking glass (Alkalark) to treat individual glasses of water, and as Balance Water Sticks designed to be inserted into your drinking bottle.

Rural Low Cost Fluoride Removal System for Drinking Water

Guideline Values of Fluoride Standards in Drinking Water: The World Health Organization (WHO) recommends 1.0 mg/L of fluoride concentration in drinking water (WHO, 1984) and the Bureau of Indian Standards IS 10500:2012 recommends requirement (acceptable) limit of 1 mg/L and permissible limit of 1.5 mg/L in drinking water sources.

There are five processes available for the treatment fluoride contaminated water. They are

• Rain water harvesting (Most Preferred in villages)
• Using surface water like ponds and wells with low Fluoride content
• Activated Alumina Filter  (The Best Absorbant)
• Nalgonda technique. and
• Reverse osmosis process (RO)

Read More http://www.appropedia.org/Water_defluoridation

Read even more on : http://www.bibliotecapleyades.net/salud/salud_fluor23.htm

The World Health Organization created the following flowchart to aid in the decision making process

Red clay is being used to remove fluoride which may be a low-cost alternative to Activated Alumina, Bone charcoal and Reverse Osmosis (RO).

WATER TREATMENT CSIR TECHNOLOGIES

http://www.slideshare.net/indiawaterportal/water-treatmentcsir-neeriindovation-201523-january-2015

Source Article : http://www.slideshare.net/ghosh51/fluoride-contamination-in-ground-water

FOUR KALSHI FILTER AT VILLAGE( Removes Iron, Fluoride, Arsenic)

Description 

A homemade, four-pitcher filter unit, one of the simplest and most inexpensive ways treat drinking water. The first pitcher contains coarse sand. The second contains  activated alumina, third pitcher contains activated carbon, and the fourth collects the filtered water. 

A sari cloth is sometimes used as an additional filter between the top 2 kalshi. 

Benefits

• Simple
• Excellent microbial removal, Iron Removal,Fluoride and Arsenic Removal
• Can be constructed of local materials
• Cost:Minimum

Drawbacks

• Fragile
• Low flow (1-2 litres / hr.)
• Irregular flow rate, requires frequent cleaning
• Availability of activated alumina

Cost :Rs.500/=

Operating & Maintenance: replacement of activated alumina after two months

Another Low Cost Method:: NEERI JAR http://www.slideshare.net/indiawaterportal/water-treatmentcsir-neeriindovation-201523-january-2015

 DNGM FOUNDATION ACTIVATED ALUMINA CANDLE FILTER FOR ARSENIC REMOVAL

http://www.dngmresfoundation.org/content_details.php?left_menu=43

read more on http://www.affws.in/auroaquasafe

pls watch video https://www.youtube.com/watch?v=79KDgzBcCWk

INREM FOUNDATION, AHMEDABAD

basic cost of activated alumina is Rs 200 to 300 per filters. plus activated charcoal Rs 25 to removal traces of aa which is harmful, rest buckets say around rs 200, and other material together , basic making cost wld be around rs 600 to rs 800.--sunder.

ENVIS CENTER,Cheaper filters to remove arsenic
http://www.daenvis.org/success.htm Activated Alumina Granule

Domestic filterThree variations of domestic filter, all using AA, have been developed by BEG, and sponsored by UNICEF since   1999. The first was made with a steel  casing and used around three kg ofAA (costing Rs.100/kg or &1.20), but the second reduced this to one kg because it had a special porous candle (tripura), which  removes the iron prior to arsenic filtration. the flow rate has to be slow enough to ensure that there is sufficient time for the arsenic to be absorbed. The candle is made locally by baking clay, sand and rice husk in a   mould then leaving it to cure over a period of about twenty days. The second filter was cheaper because it has a ferro cement casing, but this makes it heavier - 35 kg. It is also necessary to backwash or blow air

back through the candle to displace the iron oxide sediment.  This can be a health risk.  

The third filter, developed in September 2003 by S. Smithers and J. Arnold for BEG, has fine-tuned the second design to make it cheaper, more user friendly, durable and hygienically sound, while reducing the overall weight by about five kg

READ MORE ABOUT FILTERS IN http://www.daenvis.org/success.htm

AMAL Arsenic Removal Filter- North 24 Paraganas, West Bengal

source of the article: https://arsenicnetwork.wordpress.com/2015/07/31/amal-arsenic-removal-filter-north-24-paraganas-west-bengal/

Introduction:

The unit is situated at Jaygachhi colony in Habra-I block (of Habra Municipality) in North 24 Parganas district of West Bengal. This community-level AMAL Arsenic Removal Unit (ARU) is working effectively for more than 6 years serving safe water to the 453 families residing in the colony. Initially the Arsenic Removal Filter was attached to a hand pump, which later on was converted to a pumped system by the water committee.

Date of Installation: 21st Nov’ 2005

The test result of hand pump water (12.10.2005):

Arsenic concentration: 0.08mg/L and Iron concentration: 4.12mg/

Background: A rural club was formed at Jaygachhi colony about 40 years back.  The name of this club is ‘Milan Tirtha’. The club is has a membership of about 112 which includes both males and females.  The club is engaged in different social activities towards benefit of the local population like coaching centre for football, art, and dance, yoga for children and a library and a medical clinic. The club later on took the initiative towards providing clean and arsenic safe water to its residents. In this connection ‘Jaygachhi Milantirtha Amal Filter Management Committee’ was formed which actively managed the Community-Based Arsenic removal Filter since 2005.

1. Formation of Water Committee: After installation the unit was handed over to the community i.e. owned by the beneficiaries and managed by local water committee (Jaygachhi Amal Jal Samity). The initial installation cost for the Arsenic Removal unit was borne by Water For People. The maintenance costs (replacement of spares, minor plumbing, regeneration/replacement of spent alumina, caretaker’s remuneration, water test charge, etc.) are sourced from the beneficiaries by way of levying a monthly charge per family. The water committee consists of 21 members and 75% of them are women. The management of the committee is very transparent. It maintains consolidated revenue and expenditure account and also a consolidated receipts and payment account. All the planning and decision taking are done through formal meetings held once every month with proper minutes.
2. Regeneration/ replacement of exhausted Activated Alumina: Replacement                  (new media) was done in 2009 with funds from the water committee.
3. Care Taker: One female care taker is selected for maintenance and operation of the ARU like cleaning of the water collection area, regular backwash of the filter, etc. She is paid Rs. 1000 per month as honorarium by the water committee. Sometimes another lady volunteers in collecting tariff from the users, issuance of water card to households, etc.
4. Water vending: There are three Rickshaw-van drivers who supply water to 180 households outside of Jaygachhi, about 2- 5 km away from water treatment plant. They are happy to earnRs.4000/- to Rs.6000/ per month and getting festival bonus like cash amount or dress materials.
5. Benefit derived from the arsenic mitigation programme:
   • Approximate 2500 people are avoiding risk from arsenic poisoning by using safe water which in turn is helping in minimizing healthcare costs
   • School children from an adjacent primary are also getting safe water and their mid-day meal in school is being cooked with arsenic-safe water. The water committee supplies water to the school without any charge
   • Creation of employment (caretakers, water-carriers, water facilitator, plumber, water-container seller, etc.)
   • Women empowerment
   • Awareness about safe water handling to school children who also invariably take the message home
   • Creation of public infrastructure and events
   • People no longer have to go far off places to fetch safe water
   • The facility is maintained merely by the redistribution of the economic surplus on an entire neighborhood
   Perception of the users:
   Technology: Operation and maintenance is simple and friendly for the community and also at a low cost. Care taker and Water Committee work in tandem.
   • The quality of water is clean & arsenic free
   • Palatable and pleasing to drink
   • Reducing the health symptoms like gastric problem, anorexia as well as medical expenditure and lost man days in procuring water from other sources
   Sustainability and ownership: The water treatment unit is owned by the community and increase in the number of users indicate that the project is sustainable

   Future plan: Installation of additional arsenic treatment unit from their reserve fund to cater to the increasing number of users

http://www.hinduonnet.com/holnus/218200611131220.htm

New technology to remove arsenic from water developed

New Delhi, Nov. 13 (PTI): An inexpensive technique to remove arsenic from drinking water has been developed, a finding that could be of help to millions of people living in India and other developing countries.

It is through nanotechnology -- the manipulation of materials so tiny that they are measured in nanometers or one billionth of a metre -- that the hazardous elements in drinking water could be removed.

This discovery of ultra-small specks of rust or crystals of magnetite by scientists at Rice University Centre for Biological and Environmental Nanotechnology (CBEN) in Houston has been described in the journal 'Science' where it has been mentioned that thousands of cases of arsenic poisoning each year are linked to posioned wells.

The researchers said arsenic contamination in drinking water is a global problem and while there are other ways to remove arsenic, they require extensive hardware and high-pressure pumps than run on electricity.

Scientists said their approach involves nanoparticles of iron oxide that can be produced cheaply by heating mixture of rust and vegetable oil.

Iron can bond with arsenic and hence could help remove arsenic from drinking water by simply adding rusty and then removing the bonded partciles with a magnet.

After making crystals of magnetite, they found that when they were smaller than 12 nanometers, 5,000 times smaller than the width of a human hair, they were 100 or 1,000 times more effective at removing toxic contaminants like arsenic from water than exisiting filters.

According to Vicki Colvin, the center director and the lead author of the study, magnetic particles this small were thought to only interact with a strong magnetic field.

"Because we had figured out how to make these particles in different sizes, we decided to study how big magnetic field we needed to pull the particles out of suspension. We were surprised to find that even hand-held magnets could move the nanoparticles," he said.

In an effort to find out the risks of the arsenic residue being consumed, scientists also plan to undertake field tests.

Low-cost remedies to remove arsenic

http://www.hinduonnet.com/thehindu/thscrip/print.pl?file=2004060200151100.htm&date=2004/06/02/&prd=bl&

A STAINLESS steel filter device has been found effective in the removal of arsenic from contaminated drinking water and in making it safe for human consumption.

Interestingly, the filter medium itself is a processed waste material from the steel industry. The device is easy to operate and affordable, even for use in households, according to researchers at the Naval Materials Research Laboratory (NMRL), Ambernath, Maharastra.

Six prototypes of the arsenic removal filter have been put through field trials in the arsenic-affected villages of West Bengal for more than six months.

NMRL, a laboratory under the Defence Research and Development Organisation (DRDO), has filed for a national patent for the process and an international patent (US) for the product (filter).

The main investment (one-time) in the novel device is around Rs 500 for the stainless steel filter and Rs 150for the plastic parts.

The cost of removing arsenic from the contaminated waters works out to Rs 27-30 per 1,000 litres of water.

The life of the filter is five years and it requires little maintenance — just the normal washing and replacement of active ingredients. It does not require power (electricity or battery) and is easy to operate and maintain.

The wastes generated can be converted into cement bricks that can be used for construction, say the NMRL scientists.

Explaining the use of the device, Dr Narayan Das, Director, and Ms Kshipra Misra, Scientist, NMRL, said the filter works on the principle of co-precipitation and adsorption, which is followed by filtration through treated sand. The medium used in the filter is a processed waste of the steel industry and is easily available.

The device has three containers. The reactant material is placed in the first, and the sand-bag in the second.

The water contaminated with arsenic is allowed to flow into the first container, through the second and through the cloth filters. The water thus filtered is collected in the bottom-most container.

The reactant material and sand are periodically replaced, according to the usage.

There are several waste-water treatment technologies and kits for removal of arsenic available in the market.

Their high cost, problems of waste disposal and effect on the environment have been major limitations to their acceptability, said the scientists from the Marine Biology and Environmental Sciences Division of NMRL.

Interestingly, the device was judged one of the most innovative technologies and, recently, NMRL has successfully transferred the technology to the Indian Institute of Management, Ahmedabad (IIMA). The technology has been given on a non-exclusive basis, Ms Misra said.

The next phase of the development involves the fabrication of community type filter devices that can be used in hospitals and schools, and to meet the safe drinking water demands of larger communities.

For this, NMRL has entrusted the job to the Indian Institute of Technology, Mumbai (IIT). A one-year project for the development of prototypes has been finalised, Ms Misra said.

An alarming 66 million people in the Indo-Gangetic belt and around 55 million people in neighbouring Bangladesh are exposed to the threat of arsenic poisoning as the water sources are contaminated.

The levels of arsenic found in drinking water range from 50 ppb (parts per billion) to 20 ppm (parts per million) in parts of Bihar, West Bengal and Chattisgarh States, as against 10 ppb stipulated by the WHO.

The problem of arsenic in groundwater is not unique to India. Reports of arsenic poisoning have emerged from China, Taiwan, Mongolia, Argentina, Chile, Mexico, Vietnam and even the UK, though the levels are far lower.

What happens if people drink arsenic contaminated water for long periods? The known health effects are skin cancer, bronchitis, conjunctivitis and cirrhosis.

NMRL scientists have installed arsenic removal filters in Kamdevkati and Chatra villages of 24 Paraganas District, one of the worst affected in West Bengal, and have run trials in association with `Save the Environment', an NGO and the AIIHPH (All-India Institute of Hygiene and Public Health) in September 2003.

The arsenic and iron concentration fell well below the WHO/EPA drinking water standards of less than 10 ppb and less than 300 ppb respectively.

The filtered water quality is being monitored by the NMRL team and the AIIHPH.

The Jadhavpur University has done an extensive study of the prevalence of arsenic pollution in groundwater in West Bengal and the State Government has also initiated steps to control this growing menace.

The Hyderabad-based National Geophysical Research Institute (NGRI), has also done studies to get to the source of the problem.

Four foreign funding agencies have also joined hands with the environmental engineering cell of Bengal Engineering College to install 85 arsenic-removing units in three districts of West Bengal.

They are: Water For People (a non-governmental organisation based in North America), Rotary Club of Puerto Rico, US-based Conrad N. Hilton Foundation and Das Foundation.

Bengal Engineering College, a deemed university, has installed 10 such units in 24 North Parganas.

The university has an arsenic removal unit, a device that uses activated alumina and is attached to the hand-pumped tubewells.

The alumina absorbs the arsenic and raw iron present in the water. One unit can treat 6,000 litres of water per day.

There is an ongoing Indo-Australian initiative to examine the steps being taken to eliminate arsenic and recommend cost-effective and ecologically sustainable approaches.

The Murdoch University of Australia and the Regional Research Laboratory (RRL), Bhubaneshwar are the lead organisations in this project.

The Australian Agency for International Development (AusAID) has extended support of Rs 2.7 crore. The AusAID also supports a major project in Bangladesh, where arsenic pollution is severe.

While in the short term there is an urgent need to provide immediate relief to those suffering from the ill-effects of drinking water contaminated by arsenic, the long-term solution has to be based on an scientific assessment of the reasons, sources and geographical spread of the problem and in choosing technologies that are effective and affordable, suggest the NMRL scientists.