New filter promises clean water for millions

An ingenious invention is set to bring clean water to developing countries, and while the science may be cutting edge, the materials are extremely down to earth. A handful of clay, yesterday's coffee grounds and some cow manure are the ingredients that could bring clean, safe drinking water to many developing countries. The simple new technology, developed by Australian National University (ANU) materials scientist and potter Tony Flynn, allows water filters to be made from commonly available materials an fired (or baked) using cow manure as the source of heat, without the need for a kiln (an oven for baking or drying pottery). The filters have been tested and shown to remove common pathogens (disease-producing organisms) including E-coli. The invention was born out of a project involving the Manatuto community in East Timor. A charity operating there wanted to help set up a small industrial site manufacturing water filters, but initial research found the local clay to be too fine - a problem solved by the addition of organic material. While the problems of producing a working ceramic filter in East Timor were overcome, the solution was kiln-based and particular to that community's materials and couldn't be applied elsewhere. Flynn's technique for manure firing, with no requirement for a kiln, has made this zero technology approach available anywhere it is needed. Other commercial clay filters do exist, but, even if available, with prices starting at US$5 each, they are often outside the budgets of most people in the developing world. Unlike other water filtering…