System saves water and lives through recycling excess liquid

This standalone system could solve two problems at once by finding use for waste water and improving hygiene practices in developing countries.

Spotted: Water shortages will become ever more common around the world soon, with pollution, harsh weather, and growing populations all taking their toll. Springwise has already highlighted innovations seeking to alleviate such issues. This media partnership is working to clean British waterways and a prototype could turn snow into safe drinking water. Now, a clever system could simultaneously reduce water waste and help save lives, by encouraging the practice of basic hygiene.

The World Health Organisation (WHO) estimates that four million people die from diseases that are often easily preventable through basic hygiene. Those in developing countries often lack the means to employ hygiene practices, leaving them vulnerable to diarrhoeal diseases or respiratory infections.

Research from group of environmental engineers led by Eidgenössische Technische Hochschule Zurich (ETH) Professor, Eberhard Morgenroth, has revealed a means of using greywater for washing hands. Greywater is relatively clean wastewater, taken from showers, baths and handwashing. It is not classified as clean enough for use as drinking or sanitation water, and therefore often goes to waste. By recycling greywater to use in grid-free hand-washing systems, the researchers have devised a way to improve hygiene in developing areas, without putting further strain on precious water resources. Their work is a part of the Blue Diversion Autarky project. Their system of ultrafiltration involved adding certain nutrients to the water to make it safe enough for hand-washing. Any trace of organic matter remaining in the wastewater passes through an activated carbon filter. An electrolytic cell then produces chlorine from dissolved salt, to disinfect the water during storage.