by KELLY MEAD on JUNE 19, 2008 - 10 Comments in water
An estimated 80% of all sickness in this world can be attributed to unsafe water and sanitation according to the World Health Organization (WHO). That can be seen in the annual 1.5 billion episodes of diarrhea in children under the age of 5, with about four million of those being fatal.
Since historically water filters have had to be imported to developing nations, which means increased cost and reduced availability for the populace. With the new filter design made from common place materials available in even the most remote places.
“These filters are a hollow ceramic vessel filled with charcoal. They are intended to filter out suspended silt and bacteria. However, at around $US5 each, they’re too expensive for individuals in many developing communities to consider purchasing,” stated Mr Flynn. “They are very simple to explain and demonstrate and can be made by anyone, anywhere. They don’t require any Western technology. All you need is terracotta clay, some used coffee grounds or tea leaves, a compliant cow and a match,” Mr Flynn continued “Everyone has a right to clean water, these filters have the potential to enable anyone in the world to drink water safely.”
Filter production is simple:
- A handful of crushed dry clay
- A handful of common organic material, such as coffee grounds, rice hulls, or used tea leaves
- Add water, just enough to make a stiff biscuit dough like mixture
- Shape into a cylinder shaped pot closed on one end
- Dry it in sun
- Place dried filter on a layer of dry manure, a little straw, dead leaves or shredded bark
- Add two more layers of manure mixture on top
- Light the straw, dead leaves, or shredder bark
- Keep fire going until pot is completely cured (less than an hour in most cases, as different materials will mean different times)
Since using a potters kiln can take up to eight to nine hours to achieve the temperatures needed, which can be achieved using this method in a hour or less. Also with the expensive of such a kiln being prohibitive to most people, this is an excellent method anyone can make use of. Especially since no additional technology, or added insulation is needed being able to drink safe, filtered water water in almost any location on the planet. As long as water, manure, red/yellow clay and human organic debris you can make a filter that traps pathogens.
This design is purposely not being patented in a hope that it can be freely used around the world. Their belief that even third world countries should have the ability to have clean safe drinking water.
When the organic material is burned away inside the clay during the firing process it will leave cavities that can trap pathogens in the water. It is based on the basic principal that these cavities are big enough for water to pass through while being too narrow for the dangerous pathogens and the fine materials that make water muddy and unpleasant. Testing was done with E-coli bacterium and saw the filter remove 96.4% to 99.8% of the pathogen, which is well within the recommended safe levels.
This invention came from the a World Vision project that involved the community of Manatuto, in East Timor. This project was to rehabilitate a small community of potters that was devastated in the East Timor’s civil war for Independence. It was hoped that by helping the potters to produce filters would help in two ways; one give the community clean drinking water and two provide a means of revenue for the community by producing and selling them.
Using one filter it was found to produce a liter of clean water in two hours.
Creative Commons license, which allows you to utilise all the information on this site for non-commercial purposes, providing you credit the information with the word 'off-grid.net', which should be written as one word and accompanied by a link to our web site.
17 Scawfell Street
London E2 8NG
email nick (at) off-grid.net,
call US office:
UK +44 207 729 2749