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Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Chulli Water Purifier,Professor M. Fakhrul Islam,Dept. of Applied Chemistry & Chemical Technology , Rajshahi University,Bangladesh,1,Back Information,Arsenic contaminated tube wells : Almost 25% of the total installed.,Almost lower half of the country arsenic affected.,No. of people at risk : 30 million or more.,People have already developed,arsenicosis,symptoms drinking the arsenic tainted water,2,Suggested Mitigation Options,Surface water use.,Rain water storage in concrete tanks.,Pond , river water and large water bodies : use of sand filtration.,Dug well.,These are all in effect rainwater use , but may be variously,contaminated by suspended particles dissolved impurities and,bacteria,B. Deep aquifer water use : Deep tube well based piped water system,Arsenic filters,Each has its merits and demerits from different considerations,discussed as pointed out by many. Not used widely,.,3,Other Possible Systems,Bacteria filters for surface water.,Thermal treatment of surface water after filtration.,Sunlight and UV radiation treatment of surface water.,Chemical treatment of surface water (chlorination,etc),These are,physico,chemical and chemical processes, excepting the thermal treatment,i.e,boiling of water, none are practiced in villages for different reasons,Boiling Surface water produce very safe bacteria free water but high cost due to high fuel cost,4,Cooking,-,Energy Sources in Bangladesh,Village : wood and dried plant materials & cow dung.,Small towns: Mostly wood but some gas.,Big towns: Cities in Eastern part gas; but in Western,part no gas, use bottled gas or wood.,Gas reserve: To last for another 5-6 years only if no,big reserve discovered now.,Coal: may be used in future in towns and villages,Energy position is bleak and may be same in villages and even for towns in the future. Cost increase and availability to decrease with time .,Boiling of extra water for producing safe drinking water will decrease forest area and also gas reserve very fast.,5,THE CHULLI CONCEPT,Bangladesh mud,chulli,used every where,Chulli,wastes enormous heat energy (80% ,BCSIR),Villagers cook 2-3 times daily,Waste heat use will save much energy and ultimately environment .,Chulli,temperature high inside,Alternative to Boiling,Water passed through a small,dia,. coiled pipe inside,chulli,heated to 70* or more very quickly, Bacteria killed,very fast,6,Suggested Mechanism of pasteurization,by heat treatment in coiled pipe,Very high turbulence due to heat and flow.,Many repeated contact of bacteria with hot surface (Brownian movement and turbulence).,Rapid heat transfer for large surface area compared to boiling in pot.,The following slides show the principal aspects,of,chulli,water purifier,7,Chulli Water PurifierDiagrammatic,8,A Practical Chulli Water Purifier,9,Water Flow in Hot Pipe,10,Chulli Water Purifier Data,Coil size,Chulli dimension,Operation time,Temperature of water collection,Amount of water produced,average,10” dia,Pipe 4,turns,1- 1/2 feet,Deep, 10” dia.,Rice cooking time approximately 40 minutes,70- 76*C,30 Liters+,Tota,11,Bacteria Test Data,Total coliform counts /100 ml in water,Run Initial in Pond water after pass through chulla,1 1750 0,2 2500 0,3 560000 0,N.B Analysis for other chemical water parameters not done, but assumed to be within safe limits as generally found.,12,Field Test,Till now almost 3000 chulli water purifier units installed in 11 upozillas of different districts affected with arsenic in tube wells with assistance from UNICEF by a local NGO .,Field test data match the experimental chulli purifier data .,Very highly bacteria contaminated water can be treated.,Almost all types of water from pond ,river and baor can be made bacteria free.,Clean water obtained.,Social acceptability varies place to place,13,Conclusion,Water pasteurization at no extra fuel cost.,Extremely easy to set and operate.,Large amount of bacteria free safe water produced by a single,chulli,for 2-3 families.,Very low cost (,Tk,450 for the whole unit).,All components locally available.,Principle applicable to other large waste heat generators such as rice mills ,brick kilns after thorough technical research for volume production of water from surface waters in the arsenic affected and non affected areas.,14,THANK YOU,15,
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