Dear Erich Kasten Low-cost ...

Dear Erich Kasten

Low-cost ways to treat water (CHEMICAL & PHYSICAL METHODS)

1. Ceramic filters

Clay, sawdust and a plastic bucket can make a water filter that catches dirt and disease-causing microbes .

2. Bone Char Filtration- Not all filters remove heavy metals or other toxins from the water, but crushed and charred animal bone can .

3. Slow sand Filtration - Slow sand filtration has the advantage of working on an entire community’s water source, not just individual households. Practical Action put together a technical manual for slow sand filtration systems, a complete guide to their construction and maintenance . Everything but the sink portable filter. This portable filter design proposed in response to a call for better water filtration at taps in India uses chlorine, silver beads, activated charcoal and sand. Honeybee Network posed the original problem and an E4C member posted this solution. It includes a detailed guide to the specifications, materials and construction of a portable filter built from everything but the kitchen sink.

4. Bamboo Charcoal -If cost is a bigger concern than time or convenience, the cheapest way to treat water is to leave it in a plastic bottle in the sunlight. Leave clear bottles in the sun for a few hours and the UV radiation and heat kills the microbes that cause diarrhoea and other waterborne illness. Creating charcoal from wood changes the chemical structure of the carbon molecules in a way that creates a new type of molecule. Some possibilities include: Purify drinking water , Air purification, Deodorizer.

5. Chlorine/Ozone/H2O2/ClO2/Iodine/Chloramine -We saved the most obvious and probably the most reliable treatment method for last. Chlorine/Ozone & H2O2 can work in the community water supply to kill microbes before it enters people’s jerry cans or home water supplies

Above Treatment discussed but when we discuss about cost then Ozone Plus residual chlorine is cheaper than UV.UV disinfection is cheaper than only chlorine disinfection in small scale treatment.

But most low coastwise are Sr. No. 1 to 4.

Prem Baboo