IMPACT JORNALISM DAY 2015: MEDICAL/PUBLIC HEALTH

'Blue diversion' loo flushes away toilet blues

Blue Diversion resembles a squat toilet made out of blue plastic, with two holes - for urine and faeces. Through a nitrification process, the urine is converted into fertiliser on site.
Blue Diversion resembles a squat toilet made out of blue plastic, with two holes - for urine and faeces. Through a nitrification process, the urine is converted into fertiliser on site.PHOTO: EAWAG/EOOS

This story was first published on June 20, 2015

SIX billion people worldwide own a mobile phone, but only 4.5 billion have decent toilets.

To address this problem, Swiss researchers from aquatic research institute Eawag and the Vienna- based design firm EOOS have designed a new kind of toilet, called Blue Diversion.

It was designed as part of the "Reinvent The Toilet Challenge" set by the Bill & Melinda Gates Foundation.

CLEANER AND GREENER

In many locations, infrastructures such as sewers and water treatment plants simply don't exist, and there is often not enough water available for flushing.

We wanted to design a radically different type of toilet, without the need for hefty infrastructure, at the same time as offering spotless hygiene.

- Mr Christoph Luthi, project manager at Eawag

Mr Christoph Luthi, project manager at Eawag, said: "In many locations, infrastructures such as sewers and water treatment plants simply don't exist, and there is often not enough water available for flushing.

"We wanted to design a radically different type of toilet, without the need for hefty infrastructure, at the same time as offering spotless hygiene."

Blue Diversion resembles a squat toilet made out of blue plastic, with two holes: one for urine and the other for faeces.

"The purpose of separating these is to facilitate the elimination of pathogens and save water," Mr Luthi explained.

Through a nitrification process, the urine is converted into fertiliser on site.

However, what makes it radically different is the integrated independent water circuit.

Mr Luthi said: "We have fitted our toilets with a shower head to clean the pan and also ensure anal hygiene, as practised in a great number of countries, as well as a sink to wash the hands.

"Whenever the water flows, a valve automatically shuts off the urine and faeces tanks. This enables almost all of the liquid to be recuperated."

The dirty water is disinfected by a built-in gravity-driven membrane filter. A solar-powered electrolysis system then produces chlorine, preventing undesirable bacteria from forming.

In 2013, the first prototype of Blue Diversion was successfully tested in Uganda. A new prototype is now being tested in Kenya.

Blue Diversion was awarded the 2014 Prize for Innovation by the International Water Association.

Said Mr Luthi: "Mass production will reduce the cost. The objective is to achieve a selling price of US$500 (S$667) per appliance, for a projected lifetime of 10 years."

BERTRAND BEAUTE/24 HEURES (SWITZERLAND)

A version of this article appeared in the print edition of The Straits Times on January 15, 2016, with the headline ''Blue diversion' loo flushes away toilet blues'. Print Edition | Subscribe