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The Life Bowl : Low cost water purifier
One child dies every 14 seconds from waterborne a disease, which gives you two dead children as I finish typing this sentence. What's worse is most of these people survive on less than $2 per day. Vedika Jain, a senior at the Mallya Aditi International School, Bangalore was very intrigued by the growing research and innovation in this problem. After Tata came out with ‘TATASwach’this year, apparently, the world’s most cost-effective Water Filter, Vedika prototyped " The Life Bowl".
Although only one prototype has been made so far, The “Life bowl”, a transparent, instant purifier, contains the cheapest Nano carbon tube powder (embedded in the holes at the bottom of the bowl) above which is a layer of coconut husk ( virtually no cost) that helps in the filtration of polluted water. The villager merely needs to push the bowl into the river and let buoyancy take its course. As it consists an airtight transparent lid, UV disinfection is also a further possibility. It is optimum that the villager uses the UV disinfection technique after submerging the Life-Bowl in a freshwater source,as pre-filtration is a must on all UV applications to effectively destroy microorganisms to a 99.9% kill rate. The ultraviolet radiations from the sun inactivate microorganisms. After much experimentation, it was established that the optimum temperature for UV disinfection to occur is around 35'C. Sounds extreme? The summer temperatures in North India shoot upto 45 degrees!
Expense so far:
I incurred the following costs:
- The Nanocarbon Tubes cost $5 a gram, I purchased them in New York on vacation.
- The rice husk, and plastic bottles have virtually no cost
It was a process that was ignited by Mrs.Isha Ray, an Assistant Professor at the Energy and Resources Group, UC Berkeley came to my school, Mallya Aditi International School, Bangalore to address the problem of water scarcity. The idea, like any other, evolved over time. However a significant point in the development was when I read an article regarding the TATASwach on their website.
It will cost about Rs.650, including overheads. Although it has other merits, i want to shed light on the fact that in a country like India cost is and will reamain the most important.
Idea development and experimentation:
For the purpose of simplicity, I divided my experiment into three parts; First, I made a homemade filter using 4 grams of Nano carbon tubes, a plastic bottle and cotton, followed by one using Coconut Husk Fibre (Coconut Husk Ash is commonly used in commercialized water filters) and in the third I used varied proportions of each of them.
During the run of the experiment, which involved titration, h2S strips and home water tests, the indicators were kept constant. They’re based on IS 10500: 1991 (Indian Water Standards).
The results (94-99% purity) showed that there was a limit to which how much rice husk can be added before the effect saturates.
The cost reduction possibilities are limitless.
Though there is plenty of cited literature on the internet regarding the issue, I also referred to Last Oasis: Facing Water Scarcity (The Worldwatch Environmental Alert Series) for a deeper understanding on the issue.
An URL i used constantly was :eHow.com http://www.ehow.com/how_378_test-water-purity.html#ixzz0yCXxQWAs/