Mukti Pani Filters (Freedom Water Filters) for the Prevention of Water born Diseases in Flood Affected Region of Bangladesh, India,Nepal and other nations.
http://www.bangladesh-web.com/view1.php?hidDate=2007-08-15&hidType=SCI&hidRecord=0000000000000000168695 Tuesday August 14 2007 16:23:08 PM BDT <[EMAIL PROTECTED]> Meer Husain, USA <[EMAIL PROTECTED]> Mukti Pani Filter #1 can be effectively used to prevent waterborn diseases such as cholerea, diarrhoea etc in flood affected nations. The Mukti Pani Filter is simple, cheep and very effective in removing smell and organic substances from bad water in flood affected areas. After filtration of flood affected surface water, dug well water and tube well water from above the arsenic contaminated zone, the filtered water must be treated with chlorine to kill bacteria. Please take a look at the filtration and chlorination process as given below: Mukti Pani Filter #1: is a gravity, mono media water filtration system. Granular charcoal ranges from 1.0-3.0 mm sizes are packed in a 4 to 5 gallon perforated plastic bucket. About 5 small holes of 3-4mm size at the bottom (around center) of the bucket provide water flow of 1-1.5 gallon/minute/ft2. A steel wire or plastic screen of <1.0 - >0.85 mm mesh size is placed at the bottom of the bucket (inside) to retain the charcoal grains on the screen. The charcoal grains are laid on thescreen and the thickness of the charcoal bed ranges from 5-6 inches. The charcoal or activated carbon is used as filter media to remove taste and odor causing compounds as well as organic substances from water. This filter is used when source waters are free of turbidity and color. These types of filters should be used all over Bangladesh and West Bengal of India before disinfecting waters with chlorine. The water flow through the charcoal media should not exceed more than 1 -2 gpm/ft2. This low flow of water through the charcoal media would provide enough contact/residence time to water with charcoal for removing odor, taste and organic matters. Microorganisms will not be removed by this process and as a result after filtration the water must be treated to kill pathogenic bacteria. Turbidity Removal Process: Significant amount of turbidity of low turbid water can be reduced if the waters are left undisturbed for about 2-3 hours. The silt and clay size particles are settled at the bottom of the water container. The water may then be slowly removed from the water container without agitating the settled turbid substances. This filtration process for the reduction of turbidity materials from water is the oldest known technique and people have been using this process for thousands of years. The people of Bangladesh , India, Nepal and other flood affected nations around the world may effectively reduce the turbidity of water by this process and in that case, they can effectively use Mukti Pani Filter #1 for removing odor, taste and organic compounds from waters. Disinfection of water: In developed countries, pathogenic organisms in water that cause various types of diseases such as cholera, typhoid, dysentery, diarrhea etc. are no longer a problem due to proper water protection, treatment and monitoring. Boiling water is expensive but very effective process known for centuries for killing pathogenic bacteria in water. There are several chemical disinfectants are being used today for water treatment of which chlorine disinfection is simple, inexpensive and very effective. Chlorination is the oldest method of continuous disinfection for public water supplies. There are two theories regarding chlorine disinfection mechanism. One theory views that the vigorous action of chlorine against the bacterial cell destroys bacteria. The other theory is that the organisms die of starvation because the toxic nature of chlorine inactivates enzymes which empower microorganisms to use their food supply. Both Calcium Hypochlorite and Sodium Hypochlorite are being extensively used for treatment of potable water. The chemical reactions of hypochlorites with water are as follows: Calcium Hypochlorite Reaction: Ca(OCl)2 + 2H20------> 2HOCl + Ca(OH)2 Sodium Hypochlorite Reaction: NaOCl + H20 -----------> HOCl + Na(OH) Chlorine Treatment Dosage: In USA most health organizations recommend potable water to be treated with either Calcium Hypochlorite or Sodium Hypochlorite with a concentration range from 1-4 ppm. In Bangladesh and West Bengal the same dosage can be effectively used for disinfecting water. The following chlorine dosage chart for 5% Sodium Hypochlorite (unscented) can be conveniently used for desired dosage. Quantity (gal.) 1- PPM 2-PPM 3-PPM 4-PPM 5-PPM 1000 3.0 oz 5.5 oz 8.0 oz 10.5 oz 13 oz 500 2.0 oz 3.25 oz 4.5 oz 5.75 oz 7.0 oz 200 1.0 tbsp 2.25 tbsp 3.5 tbsp 4.75 tbsp 6.0 tbsp 100 2.0 tsp 4.5 tsp 7.0 tsp 9.5 tsp 12 tsp 50 1.0 tsp 2.25 tsp 3.5 tsp 4.75 tsp 6.0 tsp 25 0.5 tsp 1.13 tsp 1.75 tsp 2.40 tsp 3.0 tsp 10 0.25 tsp 0.55 tsp 0.90 tsp 1.20 tsp 1.5 tsp 5 0.25 0.45 tsp 0.65 tsp 0.80 tsp 1.0 tsp Besides, the above chart, the following formula can also be used to calculate the amount of clorox/hypochlorites (or other bleach containing 5.25% Sodium Hypochlorite) necessary to produce a given dosage in a known volume of water: b=VC(2.44 X 10-3 or VC/410. Where b = ounces of bleach V = volume of water in gallons C = desired dosage in ppm 410 is the concentration produced by one ounce of clorox in one gallon of water. Example: add 3 ppm to 1200 gallons. b = 3 X 1200/410 = 8.78 oz. 1 oz = 2 tbsp (tbsp-tablespoon) 1 tbsp = 3 tsp (tsp-teaspoon) The filtered water should be stored in a clean and tightly covered plastic container or other corrosion resistant container for proper disinfection of water. A required amount of hypochlorite for desired concentration can be calculated from the above chart. (Example: add 4 ppm concentration to 100 gallons, the amount of hypochlorite is 9.5 tsp.). After adding hypochlorite solution, the treated water needs to be thoroughly mixed. The container should be properly covered and let stand for 30-60 minutes. After that the cover should be removed to release the chlorine gas. The treated water is now safe and ready for consumption. If the disinfected water strongly smells, the water should be aerated by pouring it from one container to another to remove smell and taste. The smell and the taste can also be removed by uncovering the container and letting water stand for 3-4 hours before consumption. If granular Calcium Hypochlorite is used , then a stock solution needs to be prepared by following manufacturer's instruction. The above chart and formula can be used for the calculation of desired amount of hypochlorites. Precautions: Before disinfection, water must be filtered first. Because the reaction of chlorine with organic matter present in unfiltered water may produce Trihalomethanes (THMs) which are known carcinogens. Therefore,water must not be disinfected with chlorine before filtration of water. Disinfection of Filter media: The filter media should be washed once a month with 4-5 gallons of water with at least 100 ppm concentration of clorox bleach. The holes of the bucket should be plugged or the bucket filter should be placed in a bigger flat container. The bleach mixed water should be poured into filter media and let stand the solution for an hour and then drain the bleach water and rinse the filter media 2-3 times with clean water. This cleaning process will kill any bacteria developed in filter media. Disinfection of Flood Affected Tubewells and Dugwells: Before using water from a flooded dugwell and tube well, it should be checked, cleaned, and disinfected. This is for health and safety purposes. Tubewell and dugwell waters could be treated with a chlorine dose of at least 500 mg/L by following standard Shock chlorination procedures. Chlorination is the oldest and best method of continuous disinfection for public water supplies. It is cheep, reliable, easy to use and monitor and it is safe and environment friendly. The NGO's, local govt. officials ,and community leaders and activists, educators and other professionals can easily and properly use the above mentioned filtration and chlorination method for providing safe water to the flood affected nations. Respectfully, Meer Husain, P.G. Professional Geologist Kansas Department of Health & Environment. And Adjunct Faculty Cowley County Community College. Team Leader-Cowley County Community College International Arsenic, Water, Ecosystem & Environment Research Center. Wichita, Kansas, USA. E Mail : [EMAIL PROTECTED]
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