Technology
efficient – sustainable – locally producible
The Structure
The filter housing consists of concrete, into which a small hose moulded in. The filtration medium: special processed crushed sand.
Our technical know-how partner: CAWST
The Function
The contaminated water is filled in at the top one to four times a day. The diffuser ensures an even distribution of the water which then seeps through the fine-grained sand layer. As a result, bacteria, worms and protozoans get stuck, especially in the upper area. A so-called biofilm appears. In the biofilm the germs from the water begin to eat each other. The few germs which made it under the biofilm die in the further course due to nutrient deficiency in the sand. Clean drinking water flows out through the outlet hose at the top - simply by gravity.
No energy at all is required for that, it’s done by gravity. The drinking water is collected in a safe container designed for this purpose and can be taken about a tap at any time. It lasts about an hour to receive 12-18 litres of filtered drinking water.
The Characteristics
The filter is especially suitable for household usage and is based on a solution close to nature. This way more than 99% of pathogenic bacteria can be filtered from up to 50 litres of water a day. The filter eliminates 100% of the worms and protozoans as well as up to 99% of all viruses. Furthermore, 95% of the water’s turbidity disappears and therefore it becomes clear. No chemicals or energy are required, so the filter is suitable for remote areas too. For maintenance no tools are required. It can be done by anybody. Due to its robust design type the filter has a minimum lifespan of ten years. As construction requires just local resources the filter is producible anywhere and protects the environment sustainably.